Change search
Refine search result
1 - 38 of 38
CiteExportLink to result list
Permanent link
Cite
Citation style
  • apa
  • harvard1
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf
Rows per page
  • 5
  • 10
  • 20
  • 50
  • 100
  • 250
Sort
  • Standard (Relevance)
  • Author A-Ö
  • Author Ö-A
  • Title A-Ö
  • Title Ö-A
  • Publication type A-Ö
  • Publication type Ö-A
  • Issued (Oldest first)
  • Issued (Newest first)
  • Created (Oldest first)
  • Created (Newest first)
  • Last updated (Oldest first)
  • Last updated (Newest first)
  • Disputation date (earliest first)
  • Disputation date (latest first)
  • Standard (Relevance)
  • Author A-Ö
  • Author Ö-A
  • Title A-Ö
  • Title Ö-A
  • Publication type A-Ö
  • Publication type Ö-A
  • Issued (Oldest first)
  • Issued (Newest first)
  • Created (Oldest first)
  • Created (Newest first)
  • Last updated (Oldest first)
  • Last updated (Newest first)
  • Disputation date (earliest first)
  • Disputation date (latest first)
Select
The maximal number of hits you can export is 250. When you want to export more records please use the Create feeds function.
  • 1.
    Amasia, Mary
    et al.
    KTH, School of Biotechnology (BIO), Proteomics and Nanobiotechnology.
    Zelenin, Sergey
    KTH, School of Biotechnology (BIO), Proteomics and Nanobiotechnology.
    Ramachandraiah, Harisha
    KTH, School of Biotechnology (BIO), Proteomics and Nanobiotechnology.
    Asalapuram, Pavankumar
    Russom, Aman
    KTH, School of Biotechnology (BIO), Proteomics and Nanobiotechnology.
    Modified DVD-drive as an integrated microfluidic system for precipitate-based detection of LAMP assay2013In: 17th International Conference on Miniaturized Systems for Chemistry and Life Sciences, MicroTAS 2013, 2013, Vol. 3, p. 1616-1618Conference paper (Refereed)
    Abstract [en]

    Loop-mediated isothermal amplification (LAMP) is a sensitive method for nucleic acid analysis, and has been demonstrated as a ideal technique for use in miniaturized microfluidic systems. While LAMP assays are often detected using absorbance or fluorescence, we demonstrate an integrated system for LAMP assays through the detection of precipitate formation using a modified commercial DVD drive. This integrated DVD drive system is able to automate the sedimentation process and scattering-based detection of accumulated precipitate, as well as maintain the constant temperature needed for LAMP analysis.

  • 2.
    Ardabili, Sahar
    et al.
    KTH, School of Biotechnology (BIO), Proteomics and Nanobiotechnology.
    Zelenin, Sergey
    KTH, School of Biotechnology (BIO), Proteomics and Nanobiotechnology.
    Ramachandraiah, Harisha
    KTH, School of Biotechnology (BIO), Proteomics and Nanobiotechnology.
    Russom, Aman
    KTH, School of Biotechnology (BIO), Proteomics and Nanobiotechnology.
    Epitope unmasking for improved immuno-magnetic isolation of Gram-negative bacteriaManuscript (preprint) (Other academic)
  • 3.
    Banerjee, I.
    et al.
    KTH, School of Biotechnology (BIO), Proteomics and Nanobiotechnology.
    Ramachandraiah, Harisha
    KTH, School of Biotechnology (BIO), Proteomics and Nanobiotechnology.
    Zelenin, Sergey
    KTH, School of Biotechnology (BIO), Proteomics and Nanobiotechnology.
    Russom, Aman
    KTH, School of Biotechnology (BIO), Proteomics and Nanobiotechnology.
    Slipdisc: A versatile sample preparation platform2015In: MicroTAS 2015 - 19th International Conference on Miniaturized Systems for Chemistry and Life Sciences, Chemical and Biological Microsystems Society , 2015, p. 1256-1258Conference paper (Refereed)
    Abstract [en]

    We present "SlipDisc", a versatile sample preparation platform based on slipchip1 technology. The SlipDisc platform uses polycarbonate CDs and laser cut PSA instead of glass and a hand-winded mechanical clock mechanism to precisely manipulate minute amount of liquid. The innovative hand-winded mechanical "clockwork" that enables sample processing from one spot to another with defined precision. As a prof of principle of bioassay, we show HRP enzyme reacting with TMB substrate and a multilayer architecture used in manipulation of magnetic beads through an immiscible oil phase. Our long-term goal is to develop a sample-in-result-out multi-parametric bioanalytical SlipDisc platform specifically designed to need the needs at resource-limited settings for point of care molecular diagnostics.

  • 4.
    Banerjee, Indradumna
    et al.
    KTH, School of Biotechnology (BIO), Proteomics and Nanobiotechnology.
    Salih, Tagrid
    KTH, School of Biotechnology (BIO), Proteomics and Nanobiotechnology.
    Ramachandraiah, Harisha
    KTH, School of Biotechnology (BIO), Proteomics and Nanobiotechnology.
    Erlandsson, J.
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Surface and Corrosion Science.
    Petterson, T.
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Surface and Corrosion Science.
    Silva, AC
    Karlsson, M
    Russom, Aman
    KTH, School of Biotechnology (BIO), Proteomics and Nanobiotechnology.
    LDH based neonatal diagnostics on a low-cost slipdisc based sample preparation platform.2016Conference paper (Refereed)
    Abstract [en]

    INTRODUCTION

    Slipdisc is developed as a sample preparation platform based on slipchip technology [1], using a handwinded clockwork mechanism allowing sample processing from one spot to another with defined precision without the need for sophisticated tools or alignment (Fig.1). An ordinary smartphone or camera can be used to image and analyse the results making it an ideal tool for resource limited settings. Here, we demonstrate a bioassay for detecting LDH (Fig.2), a crucial enzyme found in all living cells which leaks out when the cellular membrane is damaged. This makes LDH a biomarker for several medical conditions in newborns, such as Ozkiraz-13, necrotizing enterocolitis (NEC), and Asphyxia.

    EXPERIMENTAL

    For assembling the slipdisc optically transparent, robust and disposable CD like polycarbonate discs were used with superhydrophobic coating on all except the embedded microfluidic channels. For the LDH assay, heparinized plasma samples were spiked with 7 different concentrations of the LDH enzyme (Lee Biosolutions, USA). These concentrations ranged from clinically normal to abnormal concentrations and used to construct a standard curve for LDH enzyme.

    RESULTS AND DISCUSSION

    The ability of the SlipDisc to quantify LDH enzyme levels from plasma samples was evaluated (Fig.3). Using 7 different concentrations, a standard curve with clinically relevant LDH concentrations was obtained (Fig4). Image and data analyses, including linear regression and Pearson’s correlation, were completed using Image processing tool in Matlab.

    CONCLUSION

    We demonstrate a low-cost neonatal diagnostics platform for the detection of LDH from plasma using a novel SlipDisc platform. The SlipDisc can further be modified to separate plasma from whole blood samples in order to fully integrate the assay. Its simple operation and smartphone based detection capabilities make it an ideal device for point-of-care neonatal diagnostics.

  • 5.
    Banerjee, Indradumna
    et al.
    KTH, School of Biotechnology (BIO), Proteomics and Nanobiotechnology.
    Salih, Tagrid
    KTH, School of Biotechnology (BIO), Proteomics and Nanobiotechnology.
    Ramachandraiah, Harisha
    KTH, School of Biotechnology (BIO), Proteomics and Nanobiotechnology. KTH, Centres, Science for Life Laboratory, SciLifeLab.
    Erlandsson, Johan
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Fibre Technology.
    Pettersson, Torbjörn
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Surface and Corrosion Science. KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Fibre Technology. KTH, School of Chemical Science and Engineering (CHE), Centres, Wallenberg Wood Science Center. KTH, School of Engineering Sciences (SCI), Centres, VinnExcellence Center BiMaC Innovation. KTH, Superseded Departments (pre-2005), Chemistry.
    Araújo, A. C.
    Karlsson, M.
    Russom, Aman
    KTH, School of Biotechnology (BIO), Proteomics and Nanobiotechnology. KTH, Centres, Science for Life Laboratory, SciLifeLab.
    Slipdisc: A versatile sample preparation platform for point of care diagnostics2017In: RSC Advances, ISSN 2046-2069, E-ISSN 2046-2069, Vol. 7, no 56, p. 35048-35054Article in journal (Refereed)
    Abstract [en]

    We report a microfluidic sample preparation platform called "Slipdisc" based on slipchip technology. Slipdisc is a rotational slipchip that uses a unique hand-wound clockwork mechanism for precise movement of specially fabricated polycarbonate discs. In operation, the microchannels and microchambers carved on the closely aligned microfluidic discs convert from continuous filled paths to defined compartments using the slip movement. The clockwork mechanism introduced here is characterised by a food dye experiment and a conventional HRP TMB reaction before measuring lactate dehydrogenase (LDH) enzyme levels, which is a crucial biomarker for neonatal diagnostics. The colorimetry based detection of LDH was performed with an unmodified camera and an image analysis procedure based on normalising images and observing changes in red channel intensity. The analysis showed a close to unity coefficient of determination (R2 = 0.96) in detecting the LDH concentration when compared with a standard Chemical Analyser, demonstrating the excellent performance of the slipdisc platform with colorimetric detection. The versatile point of care sample preparation platform should ideally be suited for a multitude of applications at resource-limited settings.

  • 6.
    Etcheverry, S.
    et al.
    KTH, School of Engineering Sciences (SCI), Applied Physics.
    Faridi, A.
    KTH, School of Biotechnology (BIO), Proteomics and Nanobiotechnology.
    Ramachandraiah, H.
    KTH, School of Biotechnology (BIO), Proteomics and Nanobiotechnology.
    Margulis, W.
    KTH, School of Engineering Sciences (SCI), Applied Physics.
    Laurell, F.
    KTH, School of Engineering Sciences (SCI), Applied Physics.
    Russom, A.
    KTH, School of Engineering Sciences (SCI), Applied Physics.
    Optofludics in microstructured fibers combining particle elasto-inertial focusing and fluorescence2016In: 2016 CONFERENCE ON LASERS AND ELECTRO-OPTICS (CLEO), IEEE conference proceedings, 2016Conference paper (Refereed)
    Abstract [en]

    Optofluidics is exploited in an all-fiber component to detect and identify through fluorescence particles flowing at high rate and inertially focused in a capillary. The system represents a first step towards an in-fiber flow cytometer.

  • 7.
    Etcheverry, Sebastian
    et al.
    KTH, School of Engineering Sciences (SCI), Applied Physics, Laser Physics.
    Faridi, Asim
    KTH, School of Biotechnology (BIO), Proteomics and Nanobiotechnology.
    Ramachandraiah, Harisha
    KTH, School of Biotechnology (BIO), Proteomics and Nanobiotechnology.
    Kumar, Tharagan
    KTH, School of Biotechnology (BIO), Proteomics and Nanobiotechnology.
    Margulis, Walter
    KTH, School of Engineering Sciences (SCI), Applied Physics, Laser Physics.
    Laurell, Fredrik
    KTH, School of Engineering Sciences (SCI), Applied Physics, Laser Physics.
    Russom, Aman
    KTH, School of Biotechnology (BIO), Proteomics and Nanobiotechnology.
    All silica fibre microflow cytometerManuscript (preprint) (Other academic)
    Abstract [en]

    Flow cytometry is currently the gold standard for analysis of cells in the medical laboratory and biomedical research. Fuelled by the need of point-of-care diagnosis, a significant effort has been made to miniaturize and reduce cost of flow cytometers. However, despite recent advances, current microsystems remain less versatile and much slower than their large-scale counterparts. In this work, an all-silica fibre microflow cytometer is presented that measures fluorescence and scattering from particles and cells. It integrates cell transport in circular capillaries and light delivery by optical fibres   Single-stream cell focusing is performed by Elasto-inertial microfluidics to guarantee optical accuracy and sensitivity.  The capability of this technique is extended to high flow rates (up to 800 µl/min), enabling throughput of 2500 particles/s. The robust, portable and low-cost system described here could be the basis for a point-of-care flow cytometer with a performance comparable to commercial systems. 

  • 8.
    Etcheverry, Sebastian
    et al.
    KTH, School of Engineering Sciences (SCI), Applied Physics.
    Faridi, Muhammad Asim
    KTH. mafaridi@kth.se.
    Ramachandraiah, Harisha
    KTH, School of Biotechnology (BIO), Proteomics and Nanobiotechnology.
    Margulis, Walter
    Laurell, Fredrik
    KTH, School of Engineering Sciences (SCI), Applied Physics.
    Russom, Aman
    KTH, School of Biotechnology (BIO), Proteomics and Nanobiotechnology.
    Optical Fiber inertial focusing based micro FlowcytometerIn: Nature Communications, ISSN 2041-1723, E-ISSN 2041-1723Article in journal (Refereed)
    Abstract [en]

    Flow cytometry is a powerful method for analysis of cells and particles. Fueled by the need for point of care diagnostic applications, a significant effort has been made to miniaturize flow cytometry. However, despite recent advances, current microflow cytometers remain less versatile and much slower than their large-scale counterparts. Here, we present a portable all-silica optofluidic device that integrates particle focusing in flow through cylindrical silica capillaries and light delivery in optical fibers to simultaneously measure fluorescence and scattering from cells and particles at a rate of 2500 particles/s – a throughput comparable to conventional cytometers. Precise 3D cell focusing and ordering is accomplished using extended elasto-inertial focusing (EEF), a key enabler for eliminating the sheath fluid commonly employed in flow cytometry with maintained high throughput. We demonstrate simultaneously two-color fluorescence and scattering measurement of different sized particles and cells. This robust and low-cost optofluidic device, assembled without the need of clean-room facilities, is ideal suited for point of care applications.

  • 9.
    Etcheverry, Sebastián
    et al.
    KTH, School of Engineering Sciences (SCI), Applied Physics, Laser Physics. RISE Acreo AB, Sweden.
    Faridi, Muhammad Asim
    KTH, School of Biotechnology (BIO), Proteomics and Nanobiotechnology. KTH, Centres, Science for Life Laboratory, SciLifeLab.
    Ramachandraiah, Harisha
    KTH, School of Biotechnology (BIO), Proteomics and Nanobiotechnology. KTH, Centres, Science for Life Laboratory, SciLifeLab.
    Kumar, T.
    KTH, School of Biotechnology (BIO), Proteomics and Nanobiotechnology. KTH, Centres, Science for Life Laboratory, SciLifeLab.
    Margulis, Walter
    KTH, School of Engineering Sciences (SCI), Applied Physics, Laser Physics. RISE Acreo AB, Sweden.
    Laurell, Fredrik
    KTH, School of Engineering Sciences (SCI), Applied Physics, Laser Physics.
    Russom, Aman
    KTH, School of Biotechnology (BIO), Proteomics and Nanobiotechnology. KTH, Centres, Science for Life Laboratory, SciLifeLab.
    High performance micro-flow cytometer based on optical fibres2017In: Scientific Reports, ISSN 2045-2322, E-ISSN 2045-2322, Vol. 7, article id 5628Article in journal (Refereed)
    Abstract [en]

    Flow cytometry is currently the gold standard for analysis of cells in the medical laboratory and biomedical research. Fuelled by the need of point-of-care diagnosis, a significant effort has been made to miniaturize and reduce cost of flow cytometers. However, despite recent advances, current microsystems remain less versatile and much slower than their large-scale counterparts. In this work, an all-silica fibre microflow cytometer is presented that measures fluorescence and scattering from particles and cells. It integrates cell transport in circular capillaries and light delivery by optical fibres. Single-stream cell focusing is performed by Elasto-inertial microfluidics to guarantee accurate and sensitive detection. The capability of this technique is extended to high flow rates (up to 800 mu l/min), enabling a throughput of 2500 particles/s. The robust, portable and low-cost system described here could be the basis for a point-of-care flow cytometer with a performance comparable to commercial systems.

  • 10.
    Etcheverry, Sebastián
    et al.
    KTH, School of Engineering Sciences (SCI), Applied Physics. Dept. of Fiber Optics, Acreo Swedish ICT AB, Sweden .
    Faridi, Muhammad Asim
    KTH, School of Biotechnology (BIO), Proteomics and Nanobiotechnology.
    Ramachandraiah, Harisha
    KTH, School of Biotechnology (BIO), Proteomics and Nanobiotechnology.
    Margulis, W.
    Laurell, Fredrik
    KTH, School of Engineering Sciences (SCI), Applied Physics.
    Russom, Aman
    KTH, School of Biotechnology (BIO), Proteomics and Nanobiotechnology.
    All fiber based micro-flow cytometer by combining optical fiber with inertial focusing2016In: 20th International Conference on Miniaturized Systems for Chemistry and Life Sciences, MicroTAS 2016, Chemical and Biological Microsystems Society , 2016, p. 1655-1656Conference paper (Refereed)
    Abstract [en]

    Towards a portable point of care flow cytometry platform, we present here an integrated all optical fiber-based optofluidic system capable of counting and discriminating fluorescent particles and cells. The robust and compact device incorporates optical fibers and circular capillaries to build an all-fiber optofluidic device to enable counting particles based on their fluorescent and back-scatter light emission. Here, we combine this with inertial- and elasto-inertial microfluidics for sheathless particle and cell focusing for integrated detection with scattering and fluorescence detections - all necessary components of standard cytometers. We validated the system for cell counting based on scattering and fluorescence.

  • 11.
    Faridi, M. A.
    et al.
    KTH, School of Biotechnology (BIO). KTH, Centres, Science for Life Laboratory, SciLifeLab.
    Ramachandraiah, H.
    KTH, School of Biotechnology (BIO).
    Iranmanesh, I. S.
    KTH, School of Biotechnology (BIO). KTH, School of Engineering Sciences (SCI), Applied Physics.
    Grishenkov, Dmitry
    KTH, School of Technology and Health (STH), Medical Engineering, Medical Imaging.
    Wiklund, Martin
    KTH, School of Engineering Sciences (SCI), Applied Physics.
    Russom, Aman
    KTH, School of Biotechnology (BIO), Proteomics and Nanobiotechnology.
    Microbubble assisted cell sorting by acoustophoresis2016In: 20th International Conference on Miniaturized Systems for Chemistry and Life Sciences, MicroTAS 2016, Chemical and Biological Microsystems Society , 2016, p. 1677-1678Conference paper (Refereed)
    Abstract [en]

    Polymer shelled gas microbubbles (MBs) are used to sort cells in a microfluidic chip under acoustic standing waves (SW). When particles are subjected to SW based on their acoustic contrast factor (ACF) they migrate to nodes (positive contrast factor particles; PACP) or antinodes (negative acoustic contrast particles; NACP)[1]. We have bounded functionalized MBs with cells such that, they can be selectively migrated to antinodes under SW and sorted from unbounded cell both in no flow and flow conditions. Here we demonstrate acoustic mediated microbubble tagged cell sorting with 75% efficiency.

  • 12.
    Faridi, Muhammad Asim
    et al.
    KTH. mafaridi@kth.se.
    Iranmanesh, Ida Sadat
    KTH.
    Ramachandraiah, Harisha
    Vanderleyden, Els
    Dubruel, Peter
    Wiklund, Martin
    KTH, School of Engineering Sciences (SCI), Applied Physics.
    Russom, Aman
    KTH, School of Biotechnology (BIO), Proteomics and Nanobiotechnology.
    Glass Capillary based cavity resonator for particle trapping study and bacteria up-concentrationIn: Biomedical microdevices (Print), ISSN 1387-2176, E-ISSN 1572-8781Article in journal (Refereed)
    Abstract [en]

    We have performed particle aggregation characterization on the basis of their material and suspending

    medium in a capillary-based cavity resonator used for acoustophoresis. We have investigated the experimental

    aggregation time of 5μm polystyrene and silica particles, size of aggregate, number of trapped particles and upconcentration

    factor in water, 0.01M phosphate buffered saline (PBS) and 0.005M PBS at 1.97MHz and with

    actuation voltages between 4, 8 and 12Vpp. We have found that there is little difference between using water and

    PBS as suspension medium, approximately 5-10% longer trapping times with PBS compared with water.

    However we get approx. 5.5 times faster trapping time for silica than for polystyrene. It is also observed and

    calculated that silica particle aggregates have 3.4 times larger area than the polystyrene aggregates using the same

    starting particle concentrations, revealing similar amount of difference in trapped number of particles. The upconcentration

    factor for silica is also about 3.2 times higher than that of polystyrene due to larger aggregate area

    of silica particles. Based on theoretical predictions and experimental characterization of the particle aggregation

    pattern, we note that the particle-particle interaction force contribution to the total acoustic radiation force is more

    pronounced for silica than for polystyrene. Finally as a proof of principle for biomedical sample preparation

    application we demonstrate the capillary-based silica particles mediated bacteria acoustophoretic upconcentration.

    This setup could potentially be utilized not only for sample preparation application but also for

    bead based affinity immunoassays.

  • 13.
    Faridi, Muhammad Asim
    et al.
    KTH, School of Biotechnology (BIO), Proteomics and Nanobiotechnology.
    Ramachandraiah, Harisha
    KTH, School of Biotechnology (BIO), Proteomics and Nanobiotechnology.
    Ardabili, Sahar
    KTH, School of Biotechnology (BIO), Proteomics and Nanobiotechnology.
    Zelenin, Sergey
    KTH, School of Biotechnology (BIO), Proteomics and Nanobiotechnology.
    Russom, Aman
    KTH, School of Biotechnology (BIO), Proteomics and Nanobiotechnology.
    Elasto-Inertial microfluidics for bacteria separation from whole blood for sepsis diagnosticsManuscript (preprint) (Other academic)
  • 14.
    Faridi, Muhammad Asim
    et al.
    KTH, School of Biotechnology (BIO), Proteomics and Nanobiotechnology. KTH, Centres, Science for Life Laboratory, SciLifeLab. mafaridi@kth.se.
    Ramachandraiah, Harisha
    KTH, School of Biotechnology (BIO), Proteomics and Nanobiotechnology. KTH, Centres, Science for Life Laboratory, SciLifeLab.
    Banerjee, Indradumna
    KTH, School of Biotechnology (BIO), Proteomics and Nanobiotechnology. KTH, Centres, Science for Life Laboratory, SciLifeLab.
    Ardabli, Sahar
    KTH, School of Biotechnology (BIO), Proteomics and Nanobiotechnology. KTH, Centres, Science for Life Laboratory, SciLifeLab.
    Zelenin, Sergey
    KTH, School of Biotechnology (BIO), Proteomics and Nanobiotechnology. KTH, Centres, Science for Life Laboratory, SciLifeLab.
    Russom, Aman
    KTH, School of Biotechnology (BIO), Proteomics and Nanobiotechnology. KTH, Centres, Science for Life Laboratory, SciLifeLab.
    Elasto-inertial microfluidics for bacteria separation from whole blood for sepsis diagnostics2017In: Journal of Nanobiotechnology, ISSN 1477-3155, E-ISSN 1477-3155, Vol. 15, article id 3Article in journal (Refereed)
    Abstract [en]

    Background: Bloodstream infections (BSI) remain a major challenge with high mortality rate, with an incidence that is increasing worldwide. Early treatment with appropriate therapy can reduce BSI-related morbidity and mortality. However, despite recent progress in molecular based assays, complex sample preparation steps have become critical roadblock for a greater expansion of molecular assays. Here, we report a size based, label-free, bacteria separation from whole blood using elasto-inertial microfluidics.

    Results: In elasto-inertial microfluidics, the viscoelastic flow enables size based migration of blood cells into a non- Newtonian solution, while smaller bacteria remain in the streamline of the blood sample entrance and can be sepa- rated. We first optimized the flow conditions using particles, and show continuous separation of 5 μm particles from 2 μm at a yield of 95% for 5 μm particle and 93% for 2 μm particles at respective outlets. Next, bacteria were continu- ously separated at an efficiency of 76% from undiluted whole blood sample.

    Conclusion: We demonstrate separation of bacteria from undiluted while blood using elasto-inertial microfluidics. The label-free, passive bacteria preparation method has a great potential for downstream phenotypic and molecular analysis of bacteria. 

  • 15.
    Faridi, Muhammad Asim
    et al.
    KTH, School of Biotechnology (BIO), Proteomics and Nanobiotechnology. KTH, Centres, Science for Life Laboratory, SciLifeLab. mafaridi@kth.se.
    Ramachandraiah, Harisha
    KTH, School of Biotechnology (BIO), Proteomics and Nanobiotechnology. KTH, Centres, Science for Life Laboratory, SciLifeLab.
    Iranmanesh, Ida Sadat
    KTH, School of Engineering Sciences (SCI), Applied Physics.
    Grishenkov, Dmitry
    KTH, School of Technology and Health (STH), Medical Engineering, Medical Imaging.
    Wiklund, Martin
    KTH, School of Engineering Sciences (SCI), Applied Physics, Biomedical and X-ray Physics.
    Russom, Aman
    KTH, School of Biotechnology (BIO), Proteomics and Nanobiotechnology.
    MicroBubble Activated Acoustic Cell Sorting: BAACSIn: Biomedical microdevices (Print), ISSN 1387-2176, E-ISSN 1572-8781Article in journal (Refereed)
    Abstract [en]

    Acoustophoresis, the ability to acoustically manipulate particles and cells inside a microfluidic channel, is a critical enabling technology for cell-sorting applications. However, one of the major impediments for routine use of acoustophoresis at clinical laboratory has been the reliance on the inherent physical properties of cells for separation. Here, we present a microfluidic-based microBubble-Activated Acoustic Cell Sorting (BAACS) method that rely on the specific binding of target cells to microbubbles conjugated with specific antibodies on their surface for continuous cell separation using ultrasonic standing wave. In acoustophoresis, cells being positive acoustic contrast particles migrate to pressure nodes. On the contrary we show that air-filled polymer-shelled microbubbles being strong negative acoustic contrast particles migrate to pressure antinodes at acoustic pressure amplitudes as low as 60 kPa. As a proof of principle, using the BAACS strategy, we demonstrate the separation of cancer cell line in a suspension with better than 75% efficiency. Moreover, 100% of the microbubble-cell conjugates migrated to the anti-node. Hence a better upstream affinity-capture has the potential to provide higher sorting efficiency. The BAACS technique may potentially provide a simplistic approach for similar sized selective isolation of cells, and is suited for applications in point of care.

  • 16.
    Faridi, Muhammad Asim
    et al.
    KTH, School of Biotechnology (BIO), Proteomics and Nanobiotechnology. KTH, Centres, Science for Life Laboratory, SciLifeLab. mafaridi@kth.se.
    Ramachandraiah, Harisha
    KTH, School of Biotechnology (BIO), Proteomics and Nanobiotechnology. KTH, Centres, Science for Life Laboratory, SciLifeLab.
    Iranmanesh, Ida Sadat
    KTH, School of Engineering Sciences (SCI), Applied Physics.
    Grishenkov, Dmitry
    KTH, School of Technology and Health (STH), Medical Engineering, Medical Imaging.
    Wiklund, Martin
    KTH, School of Engineering Sciences (SCI), Applied Physics, Biomedical and X-ray Physics.
    Russom, Aman
    KTH, School of Biotechnology (BIO), Proteomics and Nanobiotechnology.
    MicroBubble Activated Acoustic Cell Sorting: BAACS2017In: Biomedical microdevices (Print), ISSN 1387-2176, E-ISSN 1572-8781, Vol. 19, no 2, article id 23Article in journal (Refereed)
    Abstract [en]

    Acoustophoresis, the ability to acoustically manipulate particles and cells inside a microfluidic channel, is a critical enabling technology for cell-sorting applications. However, one of the major impediments for routine use of acoustophoresis at clinical laboratory has been the reliance on the inherent physical properties of cells for separation. Here, we present a microfluidic-based microBubble-Activated Acoustic Cell Sorting (BAACS) method that rely on the specific binding of target cells to microbubbles conjugated with specific antibodies on their surface for continuous cell separation using ultrasonic standing wave. In acoustophoresis, cells being positive acoustic contrast particles migrate to pressure nodes. On the contrary we show that air-filled polymer-shelled microbubbles being strong negative acoustic contrast particles migrate to pressure antinodes at acoustic pressure amplitudes as low as 60 kPa. As a proof of principle, using the BAACS strategy, we demonstrate the separation of cancer cell line in a suspension with better than 75% efficiency. Moreover, 100% of the microbubble-cell conjugates migrated to the anti-node. Hence a better upstream affinity-capture has the potential to provide higher sorting efficiency. The BAACS technique may potentially provide a simplistic approach for similar sized selective isolation of cells, and is suited for applications in point of care.

  • 17.
    Iranmanesh, Ida
    et al.
    KTH, School of Engineering Sciences (SCI), Applied Physics.
    Ohlin, Mathias
    KTH, School of Engineering Sciences (SCI), Applied Physics.
    Ramachandraiah, Harisha
    KTH, School of Biotechnology (BIO), Proteomics and Nanobiotechnology. KTH, Centres, Science for Life Laboratory, SciLifeLab.
    Russom, Aman
    KTH, School of Biotechnology (BIO), Proteomics and Nanobiotechnology. KTH, Centres, Science for Life Laboratory, SciLifeLab.
    Wiklund, Martin
    KTH, School of Engineering Sciences (SCI), Applied Physics.
    Acoustic micro-vortexing of fluids, beads and cells in disposible microfluidic chips2015In: MicroTAS 2015 - 19th International Conference on Miniaturized Systems for Chemistry and Life Sciences, Chemical and Biological Microsystems Society , 2015, p. 1005-1007Conference paper (Refereed)
    Abstract [en]

    In this paper we demonstrate a multi-functional platform using ultrasound for vortexing of 20-μl volumes of different samples in polymer-based disposable chips. The method enables different vortexing functions such as mixing laminar flows, resuspension of a micro-pellet of magnetic beads as well as cell lysis for DNA extraction. The device consists of an inexpensive low-frequency, high power, horn-shaped langevin transducer which is typically used for cell disruption in larger volumes. By controlling the operating time of this device (from fractions of a second up to a minute) different functions can be achieved. In addition, to avoid the high-power-induced heating, a simple cooling system is used as a chip holder consisting of a PC fan-cooled aluminum heat sink. To demonstrate a sample preparation application, we perform on-chip cell lysis and DNA extraction.

  • 18.
    Iranmanesh, Ida
    et al.
    KTH, School of Engineering Sciences (SCI), Applied Physics.
    Ohlin, Mathias
    KTH, School of Engineering Sciences (SCI), Applied Physics.
    Ramachandraiah, Harisha
    KTH, School of Biotechnology (BIO), Proteomics and Nanobiotechnology. KTH, Centres, Science for Life Laboratory, SciLifeLab.
    Ye, Simon
    KTH, School of Engineering Sciences (SCI), Applied Physics.
    Russom, Aman
    KTH, School of Biotechnology (BIO), Proteomics and Nanobiotechnology. KTH, Centres, Science for Life Laboratory, SciLifeLab.
    Wiklund, Martin
    KTH, School of Engineering Sciences (SCI), Applied Physics, Biomedical and X-ray Physics.
    Acoustic micro-vortexing of fluids, particles and cells in disposable microfluidic chips2016In: Biomedical microdevices (Print), ISSN 1387-2176, E-ISSN 1572-8781, Vol. 18, no 4, article id 71Article in journal (Refereed)
    Abstract [en]

    We demonstrate an acoustic platform for microvortexing in disposable polymer microfluidic chips with small-volume (20 mu l) reaction chambers. The described method is demonstrated for a variety of standard vortexing functions, including mixing of fluids, re-suspension of a pellet of magnetic beads collected by a magnet placed on the chip, and lysis of cells for DNA extraction. The device is based on a modified Langevin-type ultrasonic transducer with an exponential horn for efficient coupling into the microfluidic chip, which is actuated by a low-cost fixed-frequency electronic driver board. The transducer is optimized by numerical modelling, and different demonstrated vortexing functions are realized by actuating the transducer for varying times; from fractions of a second for fluid mixing, to half a minute for cell lysis and DNA extraction. The platform can be operated during 1 min below physiological temperatures with the help of a PC fan, a Peltier element and an aluminum heat sink acting as the chip holder. As a proof of principle for sample preparation applications, we demonstrate on-chip cell lysis and DNA extraction within 25 s. The method is of interest for automating and chip-integrating sample preparation procedures in various biological assays.

  • 19.
    Iranmanesh, Ida Sadat
    et al.
    KTH, School of Engineering Sciences (SCI), Applied Physics, Biomedical and X-ray Physics.
    Ohlin, Mathias
    KTH, School of Engineering Sciences (SCI), Applied Physics, Biomedical and X-ray Physics.
    Ramachandraiah, Harisha
    KTH, School of Biotechnology (BIO), Proteomics and Nanobiotechnology. KTH, Centres, Science for Life Laboratory, SciLifeLab.
    Russom, Aman
    KTH, School of Biotechnology (BIO), Proteomics and Nanobiotechnology. KTH, Centres, Science for Life Laboratory, SciLifeLab.
    Wiklund, Martin
    KTH, School of Engineering Sciences (SCI), Applied Physics, Biomedical and X-ray Physics.
    Acoustic micro-vortexing of fluids, beads and cells in disposable microfluidic chipsManuscript (preprint) (Other academic)
  • 20.
    Iranmanesh, Ida Sadat
    et al.
    KTH, School of Engineering Sciences (SCI), Applied Physics.
    Ramachandraiah, Harisha
    KTH, School of Biotechnology (BIO), Proteomics and Nanobiotechnology. KTH, Centres, Science for Life Laboratory, SciLifeLab.
    Russom, Aman
    KTH, School of Biotechnology (BIO), Proteomics and Nanobiotechnology. KTH, Centres, Science for Life Laboratory, SciLifeLab.
    Wiklund, Martin
    KTH, School of Engineering Sciences (SCI), Applied Physics.
    On-chip ultrasonic sample preparation for cell based assays2015In: RSC Advances, ISSN 2046-2069, E-ISSN 2046-2069, Vol. 5, no 91, p. 74304-74311Article in journal (Refereed)
    Abstract [en]

    We demonstrate an acoustophoresis method for size-based separation, isolation, up-concentration and trapping of cells that can be used for on-chip sample preparation combined with high resolution imaging for cell-based assays. The method combines three frequency-specific acoustophoresis functions in a sequence by actuating three separate channel zones simultaneously: zones for pre-alignment, size-based separation, and trapping. We characterize the mutual interference between the acoustic radiation forces between the different zones by measuring the spatial distribution of the acoustic energy density during different schemes of ultrasonic actuation, and use this information for optimizing the driving frequencies and voltages of the three utilized ultrasonic transducers attached to the chip, and the flow rates of the pumps. By the use of hydrodynamic defocusing of the pre-aligned cells in the separation zone, a cell population from a complex sample can be isolated and trapped with very high purity, followed by dynamic fluorescence analysis. We exemplify the method's potential by isolating A549 lung cancer cells from red blood cells with 100% purity, 92% separation efficiency, and 93% trapping efficiency resulting in a 130× up-concentration factor during 15 minutes of continuous sample processing through the chip. Furthermore, we demonstrate an on-chip fluorescence assay of the isolated cancer cells by monitoring the dynamic uptake and release of a fluorescence probe in individual trapped cells. The ability to combine isolation of individual cells from a complex sample with high-resolution image analysis holds great promise for applications in cellular and molecular diagnostics.

  • 21. Kjellander, Marcus
    et al.
    Billinger, Erika
    Ramachandraiah, Harisha
    KTH, School of Biotechnology (BIO). Uppsala University, Sweden.
    Boman, Mats
    Lind, Sara Bergström
    Johansson, Gunnar
    A flow-through nanoporous alumina trypsin bioreactor for mass spectrometry peptide fingerprinting2018In: Journal of Proteomics, ISSN 1874-3919, E-ISSN 1876-7737, Vol. 172, p. 165-172Article in journal (Refereed)
    Abstract [en]

    Mass spectrometry-based proteomics benefits from efficient digestion of protein samples. In this study, trypsin was immobilized on nanoporous anodized alumina membranes to create an enzyme reactor suitable for peptide mass fingerprinting. The membranes were derivatized with 3-aminopropyltriethoxysilane and the amino groups were activated with carbonyldiimidazole to allow coupling of porcine trypsin via c-amino groups. The function was assessed using the artificial substrate Na-Benzoyl-L-arginine 4-nitroanilide hydrochloride, bovine ribonuclease A and a human plasma sample. A 10-membrane flow-through reactor was used for fragmentation and MS analysis after a single pass of substrate both by collection of product and subsequent off-line analysis, and by coupling on-line to the instrument. The peptide pattem allowed correct identification of the single target protein in both cases, and of > 70 plasma proteins in single pass mode followed by LC-MS analysis. The reactor retained 76% of the initial activity after 14 days of storage and repeated use at room temperature. Significance: This manuscript describes the design of a stable enzyme reactor that allows efficient and fast digestion with negligible leakage of enzyme and enzyme fragments. The high stability facilitates the use in an online-setup with MS detection since it allows the processing of multiple samples within an extended period of time without replacement.

  • 22. Ohlander, A.
    et al.
    Bauer, S.
    Ramachandraiah, Harisha
    KTH, School of Biotechnology (BIO), Proteomics and Nanobiotechnology.
    Russom, Aman
    KTH, School of Biotechnology (BIO), Proteomics and Nanobiotechnology.
    Bock, K.
    Foil-based DNA melting curve analysis platform for low-cost point-of-care molecular diagnostics2013In: 17th International Conference on Miniaturized Systems for Chemistry and Life Sciences, MicroTAS 2013, 2013, Vol. 3, p. 1770-1772Conference paper (Refereed)
    Abstract [en]

    We report on genotyping of single nucleotide polymorphisms (SNP) by melting curve analysis (MCA) on DNA microarrays in a plastic microfluidic system with integrated heaters using lamination foils. Thin-film micro-heaters were processed on polyethylene napthalate (PEN) foil in only one metallization step. DNA microarrays were prepared directly on the PEN surface without the need of surface pre-treatment via UV-mediated immobilization of the spotted DNA microarrays. MCA in microfluidic channels is demonstrated at a ramping rate of 60°C/min, enabling ultra-rapid (50 seconds) SNP analysis.

  • 23. Pavankumar, A.M.
    et al.
    Ardabili, Sahar
    KTH, School of Biotechnology (BIO), Proteomics and Nanobiotechnology. KTH, Centres, Science for Life Laboratory, SciLifeLab.
    Zelenin, Sergey
    KTH, School of Biotechnology (BIO), Proteomics and Nanobiotechnology. KTH, Centres, Science for Life Laboratory, SciLifeLab.
    Shulte, T.
    Lundin, A.
    KTH, School of Biotechnology (BIO), Proteomics and Nanobiotechnology.
    Russom, Aman
    KTH, School of Biotechnology (BIO), Proteomics and Nanobiotechnology. KTH, Centres, Science for Life Laboratory, SciLifeLab.
    Recombinant Shigella flexneri apyrase enzyme for bioluminescence based diagnostic applicationsManuscript (preprint) (Other academic)
  • 24.
    Periyannan Rajeswari, Prem Kumar
    et al.
    KTH, School of Biotechnology (BIO), Bioprocess Technology (closed 20130101). KTH, School of Engineering Sciences (SCI), Applied Physics, Cell Physics.
    Ramachandraiah, Harisha
    KTH, School of Engineering Sciences (SCI), Applied Physics, Cell Physics.
    Hansson, Jonas
    KTH, School of Engineering Sciences (SCI), Applied Physics, Cell Physics.
    Ardabili, Sahar
    KTH, School of Engineering Sciences (SCI), Applied Physics, Cell Physics.
    Veide, Andres
    KTH, School of Biotechnology (BIO), Bioprocess Technology (closed 20130101).
    Russom, Aman
    KTH, School of Engineering Sciences (SCI), Applied Physics, Cell Physics.
    Development of microfluidic aqueous two-phase system for continuous partitioning of E. coli strains2011In: 15th International Conference on Miniaturized Systems for Chemistry and Life Sciences 2011, MicroTAS 2011, 2011, p. 1329-1331Conference paper (Refereed)
    Abstract [en]

    The interaction of bacterial cells with surrounding environment depends on its surface characteristics such as hydrophobicity, hydrophilicity balance and net charge. In this paper, aqueous two-phase system partitioning of Escherichia coli strains based on their difference in surface properties is introduced in a microfluidic system. While aqueous two-phase system is widely use to separate biomolecules on macroscale, the method has not been adapted in microfluidic system. The bacterial cells are partitioned based on their affinity for streams formed by aqueous polymers polyethylene glycol (PEG) and dextran (Dex). Partitioning efficiency of two Escherichia coli strains is currently being optimized.

  • 25.
    Pettersson, Torbjörn
    et al.
    KTH, School of Biotechnology (BIO), Proteomics and Nanobiotechnology.
    Ramachandraiah, Harisha
    KTH, School of Biotechnology (BIO), Proteomics and Nanobiotechnology.
    Russom, Aman
    KTH, School of Biotechnology (BIO), Proteomics and Nanobiotechnology.
    Nanocellulose mediated layer-by-layer chip modification for cellular in-vitro diagnostics2017In: Abstracts of Papers of the American Chemical Society, ISSN 0065-7727, Vol. 253Article in journal (Other academic)
  • 26.
    Ramachandraiah, Harisha
    KTH, School of Biotechnology (BIO), Proteomics and Nanobiotechnology.
    Microfluidic based isolation of circulating tumor cells from whole blood for cancer diagnostics2017Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Detection of circulating tumor cells (CTC) in peripheral blood is indicative of early recognition of tumor progression and such an important biomarker for early diagnosis, staging, monitoring and prognosis of cancer. However, CTC are found in very low concentrations and reliable isolation of these rare cells is challenging. Microfluidics enables precise manipulation of fluids and cells and is ideal for cell sorting methods for clinical diagnostics. The thesis contributes towards the development of microfluidic based CTC isolation methods from peripheral blood. The methods are based on size and immunoaffinity. The first part of the thesis describes the phenomenon of inertial focusing for size based cell separation at high throughputs. In paper 1, we demonstrate continuous filtration of leukocytes from diluted blood, with an efficiency of 78% at a flow rate of 2.2ml/min. In the paper 2, separation of total and subpopulation of leukocytes with a purity of 86% for granulocytes and 91% for lymphocytes is demonstrated. Furthermore, cancer cells spiked into whole blood could be separated at a yield of 88%. Finally, in paper 3 and 4 we unravel parts of the unexplored elasto-inertial microfluidics and was utilized to precisely focus the cells, as part of an integrated optofluidic micro flow cytometer device, capable to simultaneously measure fluorescence and scattering of cells and particles at a rate of 2500 particles/sec (paper 4). Second part of the thesis focuses on acoustophoresis. In (paper 5), a multifunctional acoustic microdevice was developed for isolation of cancer cells from red blood cells with a separation efficiency of 92.4% and trapping efficiency of 93%. In (paper 6), microbubbles activated acoustic cell sorter was developed for affinity based cell separation. As a proof of principle, cancer cells in a suspension were separated at an efficiency of 75%. In the third part, using cellulose nano fibrils (paper 7), we demonstrate efficiently capture and release of cancer cells at a release efficiency of 95%. Finally, a novel, single step self-assembly of spider silk proteins is introduced inside microfluidic channels for effective capture of cancer cells with 85% capture efficiency and subsequent release of captured cells with 95% release efficiency (paper 8). The novel recombinant silk modified microfluidic device was validated using pancreatic cancer patients. In summary, we have developed different microfluidic based isolation technologies for the capture and characterization of CTC.

  • 27.
    Ramachandraiah, Harisha
    et al.
    KTH, School of Biotechnology (BIO), Nano Biotechnology (closed 20130101).
    Amasia, Mary
    KTH, School of Biotechnology (BIO), Nano Biotechnology (closed 20130101).
    Cole, J.
    Sheard, P.
    Pickhaver, S.
    Walker, C.
    Lione, R.
    Russom, Aman
    KTH, School of Biotechnology (BIO), Nano Biotechnology (closed 20130101).
    Centrifugal microfluidic system for rapid, low-cost HIV diagnosis: CD4+ T-cell counting using an integrated DVD platform2012In: Proceedings of the 16th International Conference on Miniaturized Systems for Chemistry and Life Sciences, MicroTAS 2012, Chemical and Biological Microsystems Society , 2012, p. 1942-1944Conference paper (Refereed)
    Abstract [en]

    HIV is a pandemic that currently threatens over 33 million lives worldwide and HIV/AIDS remains one of the major causes of death globally. The continued monitoring of the CD4+ T-lymphocytes count in HIV patients is necessary for proper treatment, although this testing is too expensive and complex for limited resource settings. We report on a novel integrated centrifugal (CD) microfluidic system for rapid and low-cost HIV diagnosis through automated counting of CD4+ T-cells for point-of-care applications. We demonstrate the integrated T-cell immunocapture and detection mechanism using a novel system comprised of a modified commercial DVD drive and polymer disc.

  • 28.
    Ramachandraiah, Harisha
    et al.
    KTH, School of Biotechnology (BIO), Proteomics (closed 20130101). KTH, Centres, Science for Life Laboratory, SciLifeLab.
    Amasia, Mary
    KTH, Centres, Science for Life Laboratory, SciLifeLab.
    Cole, Jackie
    Sheard, Paul
    Pickhaver, Simon
    Walker, Chris
    Wirta, Valtteri
    Lexow, Preben
    Lione, Richard
    Russom, Aman
    KTH, School of Biotechnology (BIO), Proteomics (closed 20130101). KTH, Centres, Science for Life Laboratory, SciLifeLab.
    Lab-on-DVD: standard DVD drives as a novel laser scanning microscope for image based point of care diagnostics2013In: Lab on a Chip, ISSN 1473-0197, E-ISSN 1473-0189, Vol. 13, no 8, p. 1578-1585Article in journal (Refereed)
    Abstract [en]

    We present a novel "Lab-on-DVD" system and demonstrate its capability for rapid and low-cost HIV diagnostics by counting CD4+ cells isolated from whole blood. We show that a commercial DVD drive can, with certain modifications, be turned into an improved DVD-based laser scanning microscope (DVD-LSM). The system consists of a multi-layered disposable polymer disc and a modified commercial DVD reader with rotational control for sample handling, temperature control for optimized bioassay, a photodiode array for detection, and software for signal processing and user interface - all the necessary components required for a truly integrated lab-on-a-chip system, with the capability to deliver high-resolution images down to 1 mm in size. Using discs modified with antibodies, we specifically captured CD4+ cells from whole blood, demonstrating single cell resolution imaging. The novel integrated DVD platform with sub-micron image resolution brings, for the first time, affordable cellular diagnostic testing to the point-of-care and should be readily applicable at resource-limited settings.

  • 29.
    Ramachandraiah, Harisha
    et al.
    KTH, School of Biotechnology (BIO), Proteomics and Nanobiotechnology. KTH, Centres, Science for Life Laboratory, SciLifeLab.
    Ardabili, Sahar
    KTH, School of Biotechnology (BIO), Proteomics and Nanobiotechnology. KTH, Centres, Science for Life Laboratory, SciLifeLab.
    Faridi, Asim M.
    KTH, School of Biotechnology (BIO), Proteomics and Nanobiotechnology. KTH, Centres, Science for Life Laboratory, SciLifeLab.
    Gantelius, Jesper
    KTH, School of Biotechnology (BIO), Proteomics and Nanobiotechnology. KTH, Centres, Science for Life Laboratory, SciLifeLab.
    Kowalewski, Jacob M.
    Mårtensson, Gustaf
    Russom, Aman
    KTH, School of Biotechnology (BIO), Proteomics and Nanobiotechnology. KTH, Centres, Science for Life Laboratory, SciLifeLab.
    Dean flow-coupled inertial focusing in curved channels2014In: Biomicrofluidics, ISSN 1932-1058, E-ISSN 1932-1058, Vol. 8, no 3, p. 034117-Article in journal (Refereed)
    Abstract [en]

    Passive particle focusing based on inertial microfluidics was recently introduced as a high-throughput alternative to active focusing methods that require an external force field to manipulate particles. In inertial microfluidics, dominant inertial forces cause particles to move across streamlines and occupy equilibrium positions along the faces of walls in flows through straight micro channels. In this study, we systematically analyzed the addition of secondary Dean forces by introducing curvature and show how randomly distributed particles entering a simple u-shaped curved channel are focused to a fixed lateral position exiting the curvature. We found the lateral particle focusing position to be fixed and largely independent of radius of curvature and whether particles entering the curvature are pre-focused (at equilibrium) or randomly distributed. Unlike focusing in straight channels, where focusing typically is limited to channel cross-sections in the range of particle size to create single focusing point, we report here particle focusing in a large cross-section area (channel aspect ratio 1: 10). Furthermore, we describe a simple u-shaped curved channel, with single inlet and four outlets, for filtration applications. We demonstrate continuous focusing and filtration of 10 mu m particles (with > 90% filtration efficiency) from a suspension mixture at throughputs several orders of magnitude higher than flow through straight channels (volume flow rate of 4.25ml/min). Finally, as an example of high throughput cell processing application, white blood cells were continuously processed with a filtration efficiency of 78% with maintained high viability. We expect the study will aid in the fundamental understanding of flow through curved channels and open the door for the development of a whole set of bio-analytical applications.

  • 30.
    Ramachandraiah, Harisha
    et al.
    KTH, School of Biotechnology (BIO), Proteomics and Nanobiotechnology.
    Kugiejko, Karol
    KTH, School of Biotechnology (BIO).
    Pettersson, Torbjörn
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology.
    Heuchel, Rainer
    Karolinska Institutet.
    Löhr, Matthias
    karolinska Institute.
    Hedhammar, My
    KTH, School of Biotechnology (BIO), Protein Technology.
    Russom, Aman
    KTH, School of Biotechnology (BIO), Proteomics and Nanobiotechnology.
    Microfluidic based circulating tumor cell isolation and release from whole blood of pancreatic cancer patients using bio-functionalized recombinant spider silkManuscript (preprint) (Other academic)
    Abstract [en]

    A bio-functionalized microsystem was developed for the capture and release of cancer cells from whole blood. Effective isolation and purification of circulating tumor cells from whole blood provides important capability for clinical application and biological research. Here, we demonstrate a single step surface modification procedure for a microfluidic device based on self-assembly of recombinant spider silk harbouring an affinity domain for antibody binding. The surfaces of microfluidic devices were conjugated/equipped with anti-EpCAM antibody for selective isolation of pancreatic cancer cells from spiked whole blood and finally circulating tumor cells from pancreatic cancer patients. Moreover, a protease-cleavage site in the recombinant spider silk proteins provides the unique option to release the captured cancer cells on command from the device without compromising the cell’s viability. Our approach offers a simple, easy and robust surface modification process with a 85% cancer cell capture efficiency. Subsequent addition of a site-specific protease results in the release of 95% of captured cells from the bio functionalized microfluidic systems. 

  • 31.
    Ramachandraiah, Harisha
    et al.
    KTH, School of Biotechnology (BIO), Proteomics and Nanobiotechnology.
    Kumar, Tharagan
    Banerjee, Indradumna
    Russom, Aman
    KTH, Centres, Science for Life Laboratory, SciLifeLab. KTH, School of Biotechnology (BIO), Proteomics and Nanobiotechnology.
    Extended elasto-inertial microfluidics for high throughput separation in low aspect ratio spiral microchannelsManuscript (preprint) (Other (popular science, discussion, etc.))
    Abstract [en]

    Particle manipulation in viscoelastic fluid has received substantial interest because this phenomenon provides high-quality focusing. In this work, we report elasto-inertial particle focusing in spiral channels at one to two orders of magnitude higher Reynolds numbers than previously reported. We systematically investigate the interaction between inertial forces, viscoelastic forces using PEO as an elasticity enhancer and the Dean drag forces in microchannels, and report single stream particle focusing at Re > 100. Using a novel integrated 2-spiral microdevice, we applied the method to continuous focus and separate particles and report differential migration and separation 15μm from 10 μm particles at flow rate of 1 ml/min. A separation efficiency of 99% for the 15 μm and 91% for the 10μm particles was achieved. 

  • 32.
    Ramachandraiah, Harisha
    et al.
    KTH, School of Biotechnology (BIO), Proteomics and Nanobiotechnology.
    Pettersson, Torbjörn
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology.
    Russom, Aman
    KTH, School of Biotechnology (BIO), Proteomics and Nanobiotechnology.
    Layer-by-layer system based cellulose nanofibrils for capture and release of cells in microfluidic deviceManuscript (preprint) (Other (popular science, discussion, etc.))
    Abstract [en]

    Selective isolation of cells, without inducing any phenotypic changes and maintaining cell viability will preserve the information necessary for down stream analysis. Here we present an ultra thin coating on the surface of disposable microfluidic device based on cellulose nanofibrils, that is modified to capture cells and for later release. Layer-by-layer technique facilitates the production of the thin coating of cellulose onto polymeric surfaces and modified to form affinity based cell capture surface. We demonstrate an  efficiently capture and release of cells, the release is done by selectively degrading 

  • 33.
    Ramachandraiah, Harisha
    et al.
    KTH, School of Biotechnology (BIO), Proteomics and Nanobiotechnology.
    Svahn Andersson, Helene
    KTH, School of Biotechnology (BIO), Proteomics and Nanobiotechnology.
    Russom, Aman
    KTH, School of Biotechnology (BIO), Proteomics and Nanobiotechnology.
    Inertial microfluidics combined with selective cell lysis for high throughput separation of nucleated cells from whole blood2017In: RSC Advances, ISSN 2046-2069, E-ISSN 2046-2069, no 47, p. 29505-29514Article in journal (Refereed)
    Abstract [en]

    The ability to rapidly analyze and extract information from peripheral blood cells has the potential of providing a wealth of new information about immune function and general health of the patient. In spite of the tremendous progress achieved in the field of leukocyte analysis, one of the major impediments for routine analysis is the enrichment of cell populations from heterogeneous sources such as blood, as the currently used techniques tend to be laborious. Moreover, the isolation of small and transient cell populations in blood, like circulating tumor cells during cancer metastasis, is even more challenging. Here, we report an integrated device for label-free continuous flow separation of nucleated cells from unprocessed whole blood at high throughput. The method utilizes exposure to hypotonic buffer to completely remove red blood cells and at the same time a size increase of nucleated cells for inertial focusing and separation in spiral microchannel. Using an integrated device with two outlets, we isolated total leukocytes at a high yield of 99%. Furthermore cancer cells spiked into whole blood could be separated at a yield of 88% while 80% of leukocyte could be depleted into separate outlet by simply changing the resistance between the two outlets. Finally, using a three-outlet integrated device, we demonstrate fractionation of leukocyte into subpopulation. The device continuously separates granulocytes at a purity of 86%, monocyte at a purity of 43% and lymphocytes at a purity of 91% simultaneously. Finally, a cell activation study of the immune system using blood from healthy subjects, stimulated ex vivo with lipopolysaccharides (LPS), confirmed that the high operational flow rate of the device does not alter the activation levels of leukocytes or introduce artifacts. Hence, the simple, high-throughput and low-cost integrated device requiring neither external force fields nor mechanical parts to operate should readily be applicable to sort nucleated cells as stand-alone and/or as integrated lab-on-a-chip devices with high-throughput requirements.

  • 34.
    Ramachandraiah, Harisha
    et al.
    KTH, School of Biotechnology (BIO), Proteomics and Nanobiotechnology.
    Zelenin, Sergey
    KTH, School of Biotechnology (BIO), Proteomics and Nanobiotechnology.
    Amasia, Mary
    KTH, School of Biotechnology (BIO), Proteomics and Nanobiotechnology.
    Russom, Aman
    KTH, School of Biotechnology (BIO), Proteomics and Nanobiotechnology.
    In situ isothermal rolling circle amplification (RCA) of DNA and bead based visualization of RCA products on an integrated lab on DVD platform for low cost molecular diagnostics2014In: 18th International Conference on Miniaturized Systems for Chemistry and Life Sciences, MicroTAS 2014, 2014, p. 1422-1424Conference paper (Refereed)
    Abstract [en]

    Isothermal rolling circle amplification (RCA) is a simple and versatile isothermal enzymatic nucleic acid amplification techniques, and has been demonstrated as a ideal tool for biomedical research. We demonstrate for the first time the detection of padlock probes mediated and rolling circle amplification of DNA on centrifugal microfluidic system. DNA spotted on DVD substrate is amplified in-situ and novel bead-based detection of the amplified product is demonstrated using a modified commercial DVD reader for "image based" molecular diagnostics.

  • 35. Zelenin, S.
    et al.
    Ramachandraiah, Harisha
    KTH, School of Engineering Sciences (SCI), Applied Physics, Cell Physics.
    Hansson, Jonas
    KTH, School of Engineering Sciences (SCI), Applied Physics, Cell Physics.
    Ardabili, Sahar
    KTH, School of Engineering Sciences (SCI), Applied Physics, Cell Physics.
    Brismar, Hjalmar
    KTH, School of Engineering Sciences (SCI), Applied Physics, Cell Physics. Karolinska Institutet, Sweden.
    Russom, Aman
    KTH, School of Engineering Sciences (SCI), Applied Physics, Cell Physics.
    Bacteria isolation from whole blood for sepsis diagnostics2011In: 15th International Conference on Miniaturized Systems for Chemistry and Life Sciences 2011, MicroTAS 2011, 2011, p. 518-520Conference paper (Refereed)
    Abstract [en]

    Rapid and reliable detection of bloodstream infections would gain a lot from improved and straightforward isolation of highly purified bacteria from whole blood. Here, we report a microfluidics-based sample preparation strategy to continuously isolate microorganisms from whole blood for downstream analysis. The continuous-flow method takes advantage of the fact that bacteria cells have rigid cell wall enables selective and complete blood cell lysis while ~ 100% of bacteria are readily recovered. The method as a sample preparation unit offers opportunities to develop molecular based POC for sepsis diagnostics.

  • 36.
    Zelenin, Sergey
    et al.
    KTH, School of Biotechnology (BIO), Proteomics and Nanobiotechnology. KTH, Centres, Science for Life Laboratory, SciLifeLab.
    Hansson, Jonas
    KTH, School of Biotechnology (BIO), Proteomics and Nanobiotechnology. KTH, Centres, Science for Life Laboratory, SciLifeLab.
    Ardabili, Sahar
    KTH, School of Biotechnology (BIO), Proteomics and Nanobiotechnology. KTH, Centres, Science for Life Laboratory, SciLifeLab.
    Ramachandraiah, Harisha
    KTH, School of Biotechnology (BIO), Proteomics and Nanobiotechnology. KTH, Centres, Science for Life Laboratory, SciLifeLab.
    Brismar, Hjalmar
    KTH, School of Engineering Sciences (SCI), Applied Physics, Cell Physics. KTH, Centres, Science for Life Laboratory, SciLifeLab.
    Russom, Aman
    KTH, School of Biotechnology (BIO), Proteomics and Nanobiotechnology. KTH, Centres, Science for Life Laboratory, SciLifeLab.
    Microfluidic-based isolation of bacteria from whole blood for sepsis diagnostics2015In: Biotechnology letters, ISSN 0141-5492, E-ISSN 1573-6776, Vol. 37, no 4, p. 825-830Article in journal (Refereed)
    Abstract [en]

    Blood-stream infections (BSI) remain a major health challenge, with an increasing incidence worldwide and a high mortality rate. Early treatment with appropriate antibiotics can reduce BSI-related morbidity and mortality, but success requires rapid identification of the infecting organisms. The rapid, culture-independent diagnosis of BSI could be significantly facilitated by straightforward isolation of highly purified bacteria from whole blood. We present a microfluidic-based, sample-preparation system that rapidly and selectively lyses all blood cells while it extracts intact bacteria for downstream analysis. Whole blood is exposed to a mild detergent, which lyses most blood cells, and then to osmotic shock using deionized water, which eliminates the remaining white blood cells. The recovered bacteria are 100 % viable, which opens up possibilities for performing drug susceptibility tests and for nucleic-acid-based molecular identification.

  • 37. Zelenin, Sergey
    et al.
    Hansson, Jonas
    KTH, School of Engineering Sciences (SCI), Applied Physics, Cell Physics.
    Ramachandraiah, Harisha
    KTH, School of Engineering Sciences (SCI), Applied Physics, Cell Physics.
    Ardabili, Sahar
    KTH, School of Engineering Sciences (SCI), Applied Physics, Cell Physics.
    Brismar, Hjalmar
    KTH, School of Engineering Sciences (SCI), Applied Physics, Cell Physics.
    Russom, Aman
    KTH, School of Biotechnology (BIO), Nano Biotechnology (closed 20130101).
    Microfluidic selective cell lysis for bacteria isolation from whole bloodManuscript (preprint) (Other academic)
  • 38.
    Zelenin, Sergey
    et al.
    KTH, Centres, Science for Life Laboratory, SciLifeLab. KTH, School of Biotechnology (BIO), Proteomics and Nanobiotechnology.
    Ramachandraiah, Harisha
    KTH, School of Biotechnology (BIO), Proteomics and Nanobiotechnology. KTH, Centres, Science for Life Laboratory, SciLifeLab.
    Faridi, Muhammad Asim
    KTH, School of Biotechnology (BIO), Proteomics and Nanobiotechnology. KTH, Centres, Science for Life Laboratory, SciLifeLab.
    Russom, Aman
    KTH, School of Biotechnology (BIO), Proteomics and Nanobiotechnology. KTH, Centres, Science for Life Laboratory, SciLifeLab.
    Microfluidic-based bacteria isolation from whole blood for diagnostics of blood stream infection2017In: Methods in Molecular Biology: Microchip Diagnostics, Springer, 2017, p. 175-186Conference paper (Refereed)
    Abstract [en]

    Bacterial blood stream infection (BSI) potentially leads to life-threatening clinical conditions and medical emergencies such as severe sepsis, septic shock, and multi organ failure syndrome. Blood culturing is currently the gold standard for the identification of microorganisms and, although it has been automated over the decade, the process still requires 24–72 h to complete. This long turnaround time, especially for the identification of antimicrobial resistance, is driving the development of rapid molecular diagnostic methods. Rapid detection of microbial pathogens in blood related to bloodstream infections will allow the clinician to decide on or adjust the antimicrobial therapy potentially reducing the morbidity, mortality, and economic burden associated with BSI. For molecular-based methods, there is a lot to gain from an improved and straightforward method for isolation of bacteria from whole blood for downstream processing. We describe a microfluidic-based sample-preparation approach that rapidly and selectively lyses all blood cells while it extracts intact bacteria for downstream analysis. Whole blood is exposed to a mild detergent, which lyses most blood cells, and then to osmotic shock using deionized water, which eliminates the remaining white blood cells. The recovered bacteria are 100% viable, which opens up possibilities for performing drug susceptibility tests and for nucleic-acid-based molecular identification. © Springer Science+Business Media LLC 2017.

1 - 38 of 38
CiteExportLink to result list
Permanent link
Cite
Citation style
  • apa
  • harvard1
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf