Change search
ReferencesLink to record
Permanent link

Direct link
Native and functionalized micrometre-sized cellulose capsules prepared by microfluidic flow focusing
KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Fibre Technology.ORCID iD: 0000-0002-4511-1076
KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Fibre Technology.ORCID iD: 0000-0002-7410-0333
KTH, School of Engineering Sciences (SCI), Applied Physics, Cell Physics. KTH, Centres, Science for Life Laboratory, SciLifeLab.ORCID iD: 0000-0003-0578-4003
Show others and affiliations
2014 (English)In: RSC Advances, ISSN 2046-2069, Vol. 4, no 37, 19061-19067 p.Article in journal (Refereed) Published
Abstract [en]

Cellulose capsules with average outer and inner radii of approximately 44 mu m and 29 mm respectively were prepared from cellulose dissolved in a mixture of lithium chloride and dimethylacetamide using a microfluidic flow focusing device (MFFD). The MFFD had three inlets where octane oil in a cellulose solution in silicone oil was used to produce a double emulsion containing a cellulose capsule. This technique enables the formation of capsules with a narrow size distribution which can be beneficial for drug delivery or controlled release capsules. In this respect, cellulose is a highly interesting material since it is known to cause no autoimmune reactions when used in contact with human tissue. Furthermore, by controlling the chemical properties of the cellulose, it is possible to trigger a swelling of the capsules and consequentially the release of an encapsulated substance, e. g. a model drug, when the capsule becomes exposed to an external stimulus. To demonstrate this, capsules were functionalized by carboxymethylation to be pH- responsive and to expand approximately 10% when subjected to a change in pH from 3 to 10. The diffusion constant of a model drug, a 4 kDa fluorescently labelled dextran, through the native capsule wall was estimated to be 6.5 X 10(-14) m(2) s(-1) by fitting fluorescence intensity data to Fick's second law.

Place, publisher, year, edition, pages
2014. Vol. 4, no 37, 19061-19067 p.
Keyword [en]
Liquid-Liquid Systems, Drop Formation, Poly(Dimethylsiloxane), Polyelectrolytes, Biocompatibility, Microspheres, Hydrogels, Delivery, Devices, Chip
National Category
Other Chemistry Topics
URN: urn:nbn:se:kth:diva-146161DOI: 10.1039/c3ra47803cISI: 000335559100001ScopusID: 2-s2.0-84899855931OAI: diva2:722497
Science for Life Laboratory - a national resource center for high-throughput molecular bioscience

QC 20140609

Available from: 2014-06-09 Created: 2014-06-09 Last updated: 2014-08-29Bibliographically approved
In thesis
1. Macro-, Micro- and Nanospheres from Cellulose: Their Preparation, Characterization and Utilization
Open this publication in new window or tab >>Macro-, Micro- and Nanospheres from Cellulose: Their Preparation, Characterization and Utilization
2014 (English)Doctoral thesis, comprehensive summary (Other academic)
Abstract [en]

The structure of a polymeric material has a great influence in many fundamental scientific areas as well as in more applied science, since it affects the diffusion, permeability, mechanical strength, elasticity, and colloidal properties of the materials. The results in this thesis demonstrate that it is possible to fabricate solid and hollow cellulose spheres with a cellulose shell and encapsulated gas, liquid or solid particles and with a sphere size ranging from a few hundreds of nanometres to several millimetres, all with a tailored design and purpose.

The sizes of the different spheres have been controlled by three different preparation methods: large cellulose macrospheres by a solution solidification procedure, hollow micrometre-sized cellulose spheres by a liquid flow-focusing technique in microchannels, and nanometre-sized cellulose spheres by a membrane emulsification technique. 

The spheres were then modified in different ways in order to functionalize them into more advanced materials. This thesis demonstrates how to control the cellulose sphere dimensions and the wall-to-void volume ratio, the elasticity and the functionality of the spheres as such, where they were prepared to be pH-responsive, surface specific and X-ray active. These modifications are interesting in several different types of final materials such as packaging materials, drug release devices or advanced in vivo diagnostic applications.

In the more fundamental science approach, surface-smooth solid cellulose spheres were prepared for characterization of the macroscopic work of adhesion when a cellulose surface is separated from another material. Using these ultra-smooth macroscopic cellulose probes, it is possible to measure the compatibility and the surface interactions between cellulose and other materials which provide an important tool for incorporating cellulose into different composite materials. 

Place, publisher, year, edition, pages
Stockholm: KTH Royal Institute of Technology, 2014. 67 p.
TRITA-CHE-Report, ISSN 1654-1081 ; 2014:32
Cellulose, sphere, capsule, functionalization
National Category
Polymer Technologies
Research subject
Fibre and Polymer Science
urn:nbn:se:kth:diva-149807 (URN)978-91-7595-231-4 (ISBN)
Public defence
2014-09-26, F3, Lindstedtsvägen 26, KTH, Stockholm, 10:00 (English)

QC 20140829

Available from: 2014-08-29 Created: 2014-08-27 Last updated: 2014-08-29Bibliographically approved

Open Access in DiVA

No full text

Other links

Publisher's full textScopus

Search in DiVA

By author/editor
Carrick, ChristopherLarsson, Per A.Brismar, HjalmarWågberg, Lars
By organisation
Fibre TechnologyCell PhysicsScience for Life Laboratory, SciLifeLabWallenberg Wood Science Center
In the same journal
RSC Advances
Other Chemistry Topics

Search outside of DiVA

GoogleGoogle Scholar
The number of downloads is the sum of all downloads of full texts. It may include eg previous versions that are now no longer available

Altmetric score

Total: 229 hits
ReferencesLink to record
Permanent link

Direct link