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Pettersson, TorbjörnORCID iD iconorcid.org/0000-0002-5444-7276
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Svagan, A. J., Vilaplana, F., Pettersson, T., Anusuyadevi, P. R., Henriksson, G. & Hedenqvist, M. S. (2024). Centrifuge fractionation during purification of cellulose nanocrystals after acid hydrolysis and consequences on their chiral self-assembly. Carbohydrate Polymers, 328, Article ID 121723.
Öppna denna publikation i ny flik eller fönster >>Centrifuge fractionation during purification of cellulose nanocrystals after acid hydrolysis and consequences on their chiral self-assembly
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2024 (Engelska)Ingår i: Carbohydrate Polymers, ISSN 0144-8617, E-ISSN 1879-1344, Vol. 328, artikel-id 121723Artikel i tidskrift (Refereegranskat) Published
Abstract [en]

The inherent colloidal dispersity (due to length, aspect ratio, surface charge heterogeneity) of CNCs, when produced using the typical traditional sulfuric acid hydrolysis route, presents a great challenge when interpreting colloidal properties and linking the CNC film nanostructure to the helicoidal self-assembly mechanism during drying. Indeed, further improvement of this CNC preparation route is required to yield films with better control over the CNC pitch and optical properties. Here we present a modified CNC-preparation protocol, by fractionating and harvesting CNCs with different average surface charges, rod lengths, aspect ratios, already during the centrifugation steps after hydrolysis. This enables faster CNC fractionation, because it is performed in a high ionic strength aqueous medium. By comparing dry films from the three CNC fractions, discrepancies in the CNC self-assembly and structural colors were clearly observed. Conclusively, we demonstrate a fast protocol to harvest different populations of CNCs, that enable tailored refinement of structural colors in CNC films.

Ort, förlag, år, upplaga, sidor
Elsevier Ltd, 2024
Nyckelord
Cellulose nanocrystals, Fractionation, Structural colors, Sulfuric acid hydrolysis
Nationell ämneskategori
Polymerteknologi Fysikalisk kemi
Identifikatorer
urn:nbn:se:kth:diva-342832 (URN)10.1016/j.carbpol.2023.121723 (DOI)2-s2.0-85182892792 (Scopus ID)
Anmärkning

QC 20240201

Tillgänglig från: 2024-01-31 Skapad: 2024-01-31 Senast uppdaterad: 2024-02-01Bibliografiskt granskad
Li, H., Asta, N., Wang, Z., Pettersson, T. & Wågberg, L. (2024). Reevaluation of the adhesion between cellulose materials using macro spherical beads and flat model surfaces. Carbohydrate Polymers, 332, 121894-121894, Article ID 121894.
Öppna denna publikation i ny flik eller fönster >>Reevaluation of the adhesion between cellulose materials using macro spherical beads and flat model surfaces
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2024 (Engelska)Ingår i: Carbohydrate Polymers, ISSN 0144-8617, E-ISSN 1879-1344, Vol. 332, s. 121894-121894, artikel-id 121894Artikel i tidskrift (Refereegranskat) Published
Abstract [en]

Interactions between dry cellulose were studied using model systems, cellulose beads, and cellulose films, usingcustom-built contact adhesion testing equipment. Depending on the configuration of the substrates in contact,Polydimethylsiloxane (PDMS) film, cellulose films spin-coated either on PDMS or glass, the interaction showsthree distinct processes. Firstly, molecular interlocking is formed between cellulose and cellulose when there is asoft PDMS thin film backing the cellulose film. Secondly, without backing, no initial attraction force between thesurfaces is observed. Thirdly, a significant force increase, ΔF, is observed during the retraction process for cel­lulose on glass, and there is a maximum in ΔF when the retraction rate is increased. This is due to the kinetics of acontacting process occurring in the interaction zone between the surfaces caused by an interdigitation of a finefibrillar structure at the nano-scale, whereas, for the spin-coated cellulose surfaces on the PDMS backing, there isa more direct adhesive failure. The results have generated understanding of the interaction between cellulose-rich materials, which helps design new, advanced cellulose-based materials. The results also show thecomplexity of the interaction between these surfaces and that earlier mechanisms, based on macroscopic materialtesting, are simply not adequate for molecular tailoring.

Ort, förlag, år, upplaga, sidor
Elsevier BV, 2024
Nyckelord
Interaction, Cellulose thin film, Cellulose bead, Contact adhesion testing
Nationell ämneskategori
Pappers-, massa- och fiberteknik
Identifikatorer
urn:nbn:se:kth:diva-344920 (URN)10.1016/j.carbpol.2024.121894 (DOI)001183175200001 ()38431407 (PubMedID)2-s2.0-85184997085 (Scopus ID)
Forskningsfinansiär
Knut och Alice Wallenbergs Stiftelse
Anmärkning

QC 20240408

Tillgänglig från: 2024-04-03 Skapad: 2024-04-03 Senast uppdaterad: 2024-04-08
Abbasi Aval, N., Lahchaichi, E., Tudoran, O., Fayazbakhsh, F., Heuchel, R., Löhr, M., . . . Russom, A. (2023). Assessing the Layer-by-Layer Assembly of Cellulose Nanofibrils and Polyelectrolytes in Pancreatic Tumor Spheroid Formation. Biomedicines, 11(11)
Öppna denna publikation i ny flik eller fönster >>Assessing the Layer-by-Layer Assembly of Cellulose Nanofibrils and Polyelectrolytes in Pancreatic Tumor Spheroid Formation
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2023 (Engelska)Ingår i: Biomedicines, E-ISSN 2227-9059, Vol. 11, nr 11Artikel i tidskrift (Refereegranskat) Published
Abstract [en]

Three-dimensional (3D) tumor spheroids are regarded as promising models for utilization as preclinical assessments of chemo-sensitivity. However, the creation of these tumor spheroids presents challenges, given that not all tumor cell lines are able to form consistent and regular spheroids. In this context, we have developed a novel layer-by-layer coating of cellulose nanofibril–polyelectrolyte bilayers for the generation of spheroids. This technique builds bilayers of cellulose nanofibrils and polyelectrolytes and is used here to coat two distinct 96-well plate types: nontreated/non-sterilized and Nunclon Delta. In this work, we optimized the protocol aimed at generating and characterizing spheroids on difficult-to-grow pancreatic tumor cell lines. Here, diverse parameters were explored, encompassing the bilayer count (five and ten) and multiple cell-seeding concentrations (10, 100, 200, 500, and 1000 cells per well), using four pancreatic tumor cell lines—KPCT, PANC-1, MiaPaCa-2, and CFPAC-I. The evaluation includes the quantification (number of spheroids, size, and morphology) and proliferation of the produced spheroids, as well as an assessment of their viability. Notably, our findings reveal a significant influence from both the number of bilayers and the plate type used on the successful formation of spheroids. The novel and simple layer-by-layer-based coating method has the potential to offer the large-scale production of spheroids across a spectrum of tumor cell lines.

Ort, förlag, år, upplaga, sidor
MDPI AG, 2023
Nyckelord
pancreatic ductal adenocarcinoma, three-dimensional tumor model, layer-by-layer, cellulose nanofibrils
Nationell ämneskategori
Biomaterialvetenskap
Identifikatorer
urn:nbn:se:kth:diva-339943 (URN)10.3390/biomedicines11113061 (DOI)001107899000001 ()2-s2.0-85178372456 (Scopus ID)
Anmärkning

QC 20231215

Tillgänglig från: 2023-11-22 Skapad: 2023-11-22 Senast uppdaterad: 2023-12-29Bibliografiskt granskad
Abbasi Aval, N., Lahchaichi, E., Fayazbakhsh, F., Tudoran, O., Russom, A. & Pettersson, T. (2023). Evaluating the Impact of Positively Charged Polyelectrolyte Molecular Weightand Bilayer Number on Tumor Spheroid Formation in the Interaction with Negatively Charged Cellulose Nanofibrils in layer by layer assembly.
Öppna denna publikation i ny flik eller fönster >>Evaluating the Impact of Positively Charged Polyelectrolyte Molecular Weightand Bilayer Number on Tumor Spheroid Formation in the Interaction with Negatively Charged Cellulose Nanofibrils in layer by layer assembly
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2023 (Engelska)Manuskript (preprint) (Övrigt vetenskapligt)
Nationell ämneskategori
Biomaterialvetenskap
Identifikatorer
urn:nbn:se:kth:diva-339926 (URN)
Anmärkning

QC 20231127

Tillgänglig från: 2023-11-22 Skapad: 2023-11-22 Senast uppdaterad: 2023-11-29Bibliografiskt granskad
Marcioni, M., Zhao, M., Maddalena, L., Pettersson, T., Avolio, R., Castaldo, R., . . . Carosio, F. (2023). Layer-by-Layer-Coated Cellulose Fibers Enable the Production of Porous, Flame-Retardant, and Lightweight Materials. ACS Applied Materials and Interfaces, 15(30), 36811-36821
Öppna denna publikation i ny flik eller fönster >>Layer-by-Layer-Coated Cellulose Fibers Enable the Production of Porous, Flame-Retardant, and Lightweight Materials
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2023 (Engelska)Ingår i: ACS Applied Materials and Interfaces, ISSN 1944-8244, E-ISSN 1944-8252, Vol. 15, nr 30, s. 36811-36821Artikel i tidskrift (Refereegranskat) Published
Abstract [en]

New sustainable materialsproduced by green processing routes arerequired in order to meet the concepts of circular economy. The replacementof insulating materials comprising flammable synthetic polymers bybio-based materials represents a potential opportunity to achievethis task. In this paper, low-density and flame-retardant (FR) porousfiber networks are prepared by assembling Layer-by-Layer (LbL)-functionalizedcellulose fibers by means of freeze-drying. The LbL coating, encompassingchitosan and sodium hexametaphosphate, enables the formation of aself-sustained porous structure by enhancing fiber-fiber interactionsduring the freeze-drying process. Fiber networks prepared from 3 Bi-Layer(BL)-coated fibers contain 80% wt of cellulose and can easily self-extinguishthe flame during flammability tests in vertical configuration whiledisplaying extremely low combustion rates in forced combustion tests.Smoke release is 1 order of magnitude lower than that of commerciallyavailable polyurethane foams. Such high FR efficiency is ascribedto the homogeneity of the deposited assembly, which produces a protectiveexoskeleton at the air/cellulose interface. The results reported inthis paper represent an excellent opportunity for the developmentof fire-safe materials, encompassing natural components where sustainabilityand performance are maximized.

Ort, förlag, år, upplaga, sidor
American Chemical Society (ACS), 2023
Nyckelord
cellulose, porous materials, layer-by-layer, flame-retardancy, lightweight materials
Nationell ämneskategori
Textil-, gummi- och polymermaterial
Identifikatorer
urn:nbn:se:kth:diva-333805 (URN)10.1021/acsami.3c06652 (DOI)001032189600001 ()37467121 (PubMedID)2-s2.0-85166442328 (Scopus ID)
Anmärkning

QC 20230810

Tillgänglig från: 2023-08-10 Skapad: 2023-08-10 Senast uppdaterad: 2023-08-10Bibliografiskt granskad
Lopez-Guajardo, A., Zafar, A., Al Hennawi, K., Rossi, V., Alrwaili, A., Medcalf, J. D., . . . Gad, A. K. B. (2023). Regulation of cellular contractile force, shape and migration of fibroblasts by oncogenes and Histone deacetylase 6. Frontiers in Molecular Biosciences, 10, Article ID 1197814.
Öppna denna publikation i ny flik eller fönster >>Regulation of cellular contractile force, shape and migration of fibroblasts by oncogenes and Histone deacetylase 6
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2023 (Engelska)Ingår i: Frontiers in Molecular Biosciences, E-ISSN 2296-889X, Vol. 10, artikel-id 1197814Artikel i tidskrift (Refereegranskat) Published
Abstract [en]

The capacity of cells to adhere to, exert forces upon and migrate through their surrounding environment governs tissue regeneration and cancer metastasis. The role of the physical contractile forces that cells exert in this process, and the underlying molecular mechanisms are not fully understood. We, therefore, aimed to clarify if the extracellular forces that cells exert on their environment and/or the intracellular forces that deform the cell nucleus, and the link between these forces, are defective in transformed and invasive fibroblasts, and to indicate the underlying molecular mechanism of control. Confocal, Epifluorescence and Traction force microscopy, followed by computational analysis, showed an increased maximum contractile force that cells apply on their environment and a decreased intracellular force on the cell nucleus in the invasive fibroblasts, as compared to normal control cells. Loss of HDAC6 activity by tubacin-treatment and siRNA-mediated HDAC6 knockdown also reversed the reduced size and more circular shape and defective migration of the transformed and invasive cells to normal. However, only tubacin-mediated, and not siRNA knockdown reversed the increased force of the invasive cells on their surrounding environment to normal, with no effects on nuclear forces. We observed that the forces on the environment and the nucleus were weakly positively correlated, with the exception of HDAC6 siRNA-treated cells, in which the correlation was weakly negative. The transformed and invasive fibroblasts showed an increased number and smaller cell-matrix adhesions than control, and neither tubacin-treatment, nor HDAC6 knockdown reversed this phenotype to normal, but instead increased it further. This highlights the possibility that the control of contractile force requires separate functions of HDAC6, than the control of cell adhesions, spreading and shape. These data are consistent with the possibility that defective force-transduction from the extracellular environment to the nucleus contributes to metastasis, via a mechanism that depends upon HDAC6. To our knowledge, our findings present the first correlation between the cellular forces that deforms the surrounding environment and the nucleus in fibroblasts, and it expands our understanding of how cells generate contractile forces that contribute to cell invasion and metastasis.

Ort, förlag, år, upplaga, sidor
Frontiers Media SA, 2023
Nyckelord
Traction force microscopy, cellular contractile forces, intracellular forces on nucleus, fibroblasts, cell adhesion, Histone deacetylase 6, oncogenes, metastasis
Nationell ämneskategori
Cellbiologi
Identifikatorer
urn:nbn:se:kth:diva-334755 (URN)10.3389/fmolb.2023.1197814 (DOI)001044471300001 ()37564130 (PubMedID)2-s2.0-85167455683 (Scopus ID)
Anmärkning

QC 20230824

Tillgänglig från: 2023-08-24 Skapad: 2023-08-24 Senast uppdaterad: 2023-08-24Bibliografiskt granskad
Asta, N., Reid, M. S., Pettersson, T. & Wågberg, L. (2023). The Use of Model Cellulose Materials for Studying Molecular Interactions at Cellulose Interfaces. ACS Macro Letters, 12(11), 1530-1535
Öppna denna publikation i ny flik eller fönster >>The Use of Model Cellulose Materials for Studying Molecular Interactions at Cellulose Interfaces
2023 (Engelska)Ingår i: ACS Macro Letters, E-ISSN 2161-1653, Vol. 12, nr 11, s. 1530-1535Artikel i tidskrift (Refereegranskat) Published
Abstract [en]

Despite extensive research on biobased and fiber-basedmaterials, fundamental questions regarding the molecular processesgoverning fiber−fiber interactions remain unanswered. In this study, weintroduce a method to examine and clarify molecular interactions withinfiber−fiber joints using precisely characterized model materials, i.e.,regenerated cellulose gel beads with nanometer-smooth surfaces. Byphysically modifying these materials and drying them together to createmodel joints, we can investigate the mechanisms responsible for joiningcellulose surfaces and how this affects adhesion in both dry and wet statesthrough precise separation measurements. The findings reveal a subtlebalance in the joint formation, influencing the development ofnanometer-sized structures at the contact zone and likely inducingbuilt-in stresses in the interphase. This research illustrates how model materials can be tailored to control interactions betweencellulose-rich surfaces, laying the groundwork for future high-resolution studies aimed at creating stiff, ductile, and/or tough jointsbetween cellulose surfaces and to allow for the design of high-performance biobased materials.

Ort, förlag, år, upplaga, sidor
American Chemical Society (ACS), 2023
Nationell ämneskategori
Pappers-, massa- och fiberteknik
Identifikatorer
urn:nbn:se:kth:diva-344919 (URN)10.1021/acsmacrolett.3c00578 (DOI)001096724800001 ()37910654 (PubMedID)2-s2.0-85178324088 (Scopus ID)
Forskningsfinansiär
Knut och Alice Wallenbergs StiftelseStora Enso
Anmärkning

QC 20240404

Tillgänglig från: 2024-04-03 Skapad: 2024-04-03 Senast uppdaterad: 2024-04-05Bibliografiskt granskad
Li, L., Tian, W., VahidMohammadi, A., Rostami, J., Chen, B., Matthews, K., . . . Hamedi, M. (2023). Ultrastrong Ionotronic Films Showing Electrochemical Osmotic Actuation. Advanced Materials, 35(45), Article ID 2301163.
Öppna denna publikation i ny flik eller fönster >>Ultrastrong Ionotronic Films Showing Electrochemical Osmotic Actuation
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2023 (Engelska)Ingår i: Advanced Materials, ISSN 0935-9648, E-ISSN 1521-4095, Vol. 35, nr 45, artikel-id 2301163Artikel i tidskrift (Refereegranskat) Published
Abstract [en]

A multifunctional soft material with high ionic and electrical conductivity, combined with high mechanical properties and the ability to change shape can enable bioinspired responsive devices and systems. The incorporation of all these characteristics in a single material is very challenging, as the improvement of one property tends to reduce other properties. Here, a nanocomposite film based on charged, high-aspect-ratio 1D flexible nanocellulose fibrils, and 2D Ti3C2Tx MXene is presented. The self-assembly process results in a stratified structure with the nanoparticles aligned in-plane, providing high ionotronic conductivity and mechanical strength, as well as large water uptake. In hydrogel form with 20 wt% liquid, the electrical conductivity is over 200 S cm−1 and the in-plane tensile strength is close to 100 MPa. This multifunctional performance results from the uniquely layered composite structure at nano- and mesoscales. A new type of electrical soft actuator is assembled where voltage as low as ±1 V resulted in osmotic effects and giant reversible out-of-plane swelling, reaching 85% strain.

Ort, förlag, år, upplaga, sidor
Wiley, 2023
Nyckelord
cellulose nanofibrils, hydrogel actuators, ionotronic conductivity, MXenes, nanocomposite films
Nationell ämneskategori
Polymerkemi
Identifikatorer
urn:nbn:se:kth:diva-348452 (URN)10.1002/adma.202301163 (DOI)001047337200001 ()2-s2.0-85167665653 (Scopus ID)
Anmärkning

QC 20240624

Tillgänglig från: 2024-06-24 Skapad: 2024-06-24 Senast uppdaterad: 2024-06-24Bibliografiskt granskad
Zhao, M., Robertsén, L., Wågberg, L. & Pettersson, T. (2022). Adsorption of paper strength additives to hardwood fibres with different surface charges and their effect on paper strength. Cellulose, 29(4), 2617-2632
Öppna denna publikation i ny flik eller fönster >>Adsorption of paper strength additives to hardwood fibres with different surface charges and their effect on paper strength
2022 (Engelska)Ingår i: Cellulose, ISSN 0969-0239, E-ISSN 1572-882X, Vol. 29, nr 4, s. 2617-2632Artikel i tidskrift (Refereegranskat) Published
Abstract [en]

Light-weight paper products that contain less fibres, but with a maintained bulk and improved strength properties, are highly desirable due to the low cost of raw materials and improved logistics of packaged goods. In this respect, the adsorption capacity of dry strength additives onto fibres, which is affected by the surface charge of said fibres, is very important for the development of these mechanically robust paper products. The influence of the surface charge on the adsorption of strength additives was investigated for, dissolving grade fibres, kraft fibres and kraft fibres modified with carboxymethyl cellulose (CMC) with different surface charge densities, but the same fibre dimensions. The strength additives investigated were cationic starch (CS), anionic polyacrylamide (APAM) and polyelectrolyte complexes (PECs), containing CS and APAM. A linear relationship was found between the surface charge of the fibres and the saturated adsorbed amount of CS. However, when either APAM or PECs adsorbed as secondary layers onto the CS, no correlation between cellulose charge and the saturation adsorption could be observed. The adsorption of APAM was dramatically affected by the pre-adsorbed amount of CS, whereas PECs were less influenced. Moreover, the additives improved the tensile strength (60%) and strain at break (> 100%) of handsheets formed with the kraft fibres and adsorbed APAM. It was also found that CS/APAM increased the sheet density while CS/PECs lowered it. In conclusion, the gained fundamental understanding of these adsorption of additives is of significant importance to facilitate the industrial development of sustainable low-cost high-end packaging products. Graphical abstract: [Figure not available: see fulltext.]

Ort, förlag, år, upplaga, sidor
Springer Nature, 2022
Nyckelord
Anionic polyacrylamide, Birch fibres, Cationic starch, Paper dry strength, Polyelectrolytes complexes, Surface charge, Additives, Cellulose, Costs, Fibers, Paper, Polyelectrolytes, Starch, Tensile strength, Birch fiber, Cationic starches, Dry strengths, Kraft fibers, Low-costs, Paper strengths, Polyelectrolyte complexes, Strength additives, Adsorption
Nationell ämneskategori
Pappers-, massa- och fiberteknik
Identifikatorer
urn:nbn:se:kth:diva-320552 (URN)10.1007/s10570-022-04447-3 (DOI)000752239900001 ()2-s2.0-85124309994 (Scopus ID)
Anmärkning

QC 20221027

Tillgänglig från: 2022-10-27 Skapad: 2022-10-27 Senast uppdaterad: 2022-12-20Bibliografiskt granskad
Zhao, M., Robertsén, L., Wågberg, L. & Pettersson, T. (2022). Effect of saturation adsorption of paper strength additives on the performance of paper. Nordic Pulp & Paper Research Journal, 37(4), 624-635
Öppna denna publikation i ny flik eller fönster >>Effect of saturation adsorption of paper strength additives on the performance of paper
2022 (Engelska)Ingår i: Nordic Pulp & Paper Research Journal, ISSN 0283-2631, E-ISSN 2000-0669, Vol. 37, nr 4, s. 624-635Artikel i tidskrift (Refereegranskat) Published
Abstract [en]

The use of paper dry strength additives is oneof the methods for producing packaging boards with alower grammage while maintaining mechanical properties.In the present work, papers were formed using dissolvinggrade kraft fibres, kraft fibres and carboxymethylatedcellulose (CMC) modified kraft fibres (C-kraft fibres),with either cationic starch (CS), anionic polyacrylamide(APAM) or anionic polyelectrolyte complexes (PECs). Fibresand sheets were characterized to evaluate how the saturationadsorption of the different strength additives influencesthe properties of the treated fibres and the finalhandsheets. The tensile index of papers made from C-kraftfibres was the highest due to the highest adsorption capacityof strength additives. Moreover, the strength additivesincreased the tensile index by 33–84 %, while z-directional tensile strength was increased dramatically by 46–139 %.Bending stiffness was improved by 2.6–25 %, and the combination of CS and APAM or PECs resulted in a significantimprovement in bending stiffness compared to the addition of CS alone. Importantly, the strength improvement did not sacrifice the density significantly. In summary, theknowledge gained from the current study expands the understanding of strength additives and their relationship with fibres of different surface charge and the overall paper properties.

Ort, förlag, år, upplaga, sidor
Walter de Gruyter GmbH, 2022
Nyckelord
bending stiffness; birch fibres; dry strength additives; dry strength of paper; surface charge.
Nationell ämneskategori
Pappers-, massa- och fiberteknik
Forskningsämne
Fiber- och polymervetenskap
Identifikatorer
urn:nbn:se:kth:diva-322552 (URN)10.1515/npprj-2022-0080 (DOI)000879890700001 ()2-s2.0-85142334676 (Scopus ID)
Anmärkning

QC 20221227

Tillgänglig från: 2022-12-19 Skapad: 2022-12-19 Senast uppdaterad: 2024-03-15Bibliografiskt granskad
Organisationer
Identifikatorer
ORCID-id: ORCID iD iconorcid.org/0000-0002-5444-7276

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