Change search
CiteExportLink to record
Permanent link

Direct 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
Functional and Renewable Galactoglucomannan-based Hydrogels
KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology. (Polymer Technology)
2009 (English)Licentiate thesis, comprehensive summary (Other academic)
Abstract [en]

Polysaccharides represent an important resource for a variety of products, from food via fuel supply to functional materials of every kind. Here they are, due to their natural diversity found in many special applications, e.g. in the biomedical sector.

Lately, a fairly unused group of polysaccharides, so called hemicelluloses, attracts more and more attention due to its high availability and promising properties.

This thesis presents the utilization of the water-soluble species O-acetyl-galactoglucomannan (AcGGM),   derived from softwood, as raw material for the synthetic design of functional hydrogels. AcGGM was used thanks to its great availability and high hydrophilicity rendering it an excellent material for hydrogels design.

For this purpose, a three-step-method was devised consisting of (1) the carbonyldiimidazole activation of primary hydroxylated vinylic compounds, (2) the substitution of hydroxyl groups of the AcGGM backbone with vinylic functions, and (3) radical crosslinking yielding in a hydrophilic three-dimensional network – a hydrogel.

Crosslinking strategies were varied from photo-crosslinking in DMSO to redox-initiated crosslinking in H2O with the objective of adapting the synthesis to benign conditions. Varying the crosslinking-species as well as the media was found to have a significant influence on the resulting gels’ properties, such as swelling capacity and G-modulus.  Here, swelling capacity could be affected to vary between ~0.6 to ~23 times of the gels self-weight and the G-modulus ranged from 0.4 to 145 kPa.

AcGGM and 2-hydroxy ethyl methacrylate (HEMA) gels were studied further and evaluated for their suitability as drug delivery systems for two model drugs (caffeine and Vitasyn Blue) varying in size, polarity and hydrophilicity. Here, the gels’ composition as well as a second modification with maleic acid anhydride was proved to affect the release properties significantly.

Based on our findings we conclude that the presented library is an important step to the promising future of these hydrogels based on the renewable resource AcGGM.

Place, publisher, year, edition, pages
Stockholm: Fiber- och polymerteknologi , 2009. , iii, 48 p.
Series
Trita-CHE-Report, ISSN 1654-1081 ; 2009:22
Keyword [en]
Polysaccharides, hydrogels, swelling, crosslinking, hemicellulose, release
Keyword [sv]
polysackarider, hemicellulosa, hydrogel, läkemedelsfrisättning, förnyelsebar, tvärbindning.
National Category
Other Materials Engineering
Identifiers
URN: urn:nbn:se:kth:diva-10474ISBN: 978-91-7415-350-7 (print)OAI: oai:DiVA.org:kth-10474DiVA: diva2:217937
Presentation
2009-05-10, K1, KTH, Teknikringen 56, Stockholm, 10:00 (English)
Opponent
Supervisors
Projects
Gröna MaterialPulp Mill Biorefinery
Available from: 2009-05-26 Created: 2009-05-18 Last updated: 2010-11-03Bibliographically approved
List of papers
1. Drug Diffusion in Neutral and Ionic Hydrogels Assembled from Acetylated Galactoglucomannan
Open this publication in new window or tab >>Drug Diffusion in Neutral and Ionic Hydrogels Assembled from Acetylated Galactoglucomannan
Show others...
2009 (English)In: Journal of Applied Polymer Science, ISSN 0021-8995, E-ISSN 1097-4628, Vol. 112, no 4, 2401-2412 p.Article in journal (Refereed) Published
Abstract [en]

In this study, hydrogels based on acetylated galactoglucomannan (AcGGM)-a hemicellulose present in softwood-were synthesized and examined for their properties in drug-release systems using two model Substances of different molecular weight, size, and polarity (caffeine and vitasyn blue). Neutral hydrogels were produced from functionalized AcGGM using hydroxyethyl methacrylate (HEMA) coupled via carbonyldiimidazole (CDI) and a co-monomer in a radical-initiated polymerization. Through a second modification reaction between the HEMA-modified AcGGM (M-AcGGM-methacrylated AcGGM) and maleic anhydride, a "double-modified" AcGGM (CM-AcGGM-carboxylated M-AcGGM) was successfuly, formed that could be cross-linked to form ionic hydrogels by the very same polymerization method. The neutral hydrogels showed drug release kinetics that could be easily regulated by changing the relative amount of the methacrylated AcGGM and its corresponding degree of methacrylation. The drug release rate and the Fickian swelling cl creased with an increase in these two aforementioned parameters. The ionic hydrogels showed quicker release kinetics and higher swelling capabilities than the corresponding nonionic gels did, especially at neutral conditions. Under acidic conditions, the release speed was lowered as expected because of protonation of carboxylic functionalities. Based on the findings we conclude that these novel hemicellulose-containing hydrogels have future prospects in drug release formulations, e.g., in a later stage of development for application in oral drug administration technology.

Keyword
hemicellulose, hydrogels, renewable resources, release, cross-linking, hemicellulose-based hydrogels, spruce picea-abies, renewable sources, biodegradable polymers, l. karst, wood, films, water
National Category
Other Materials Engineering
Identifiers
urn:nbn:se:kth:diva-18275 (URN)10.1002/app.29878 (DOI)000264449500065 ()2-s2.0-64249084593 (Scopus ID)
Note
QC 20100525Available from: 2010-08-05 Created: 2010-08-05 Last updated: 2017-12-12Bibliographically approved
2. Alkenyl-Functionalized Precursors for Renewable Hydrogels Design
Open this publication in new window or tab >>Alkenyl-Functionalized Precursors for Renewable Hydrogels Design
2009 (English)In: Journal of Polymer Science Part A: Polymer Chemistry, ISSN 0887-624X, E-ISSN 1099-0518, Vol. 47, no 14, 3595-3606 p.Article in journal (Refereed) Published
Abstract [en]

A library of crosslinking chemistries for the hydrogel synthesis based on the hemicellulose acetylated galactoglucomannan (AcGGM) has been developed, demonstrated, and evaluated. A three-step route was elaborated including (1) the carbonyldiimidazole activation of primary hydroxylated vinylic molecules such as acrylates, vinyl alcohols, and vinyl ethers, (2) the covalent coupling of the alkenyl precursors to the polysaccharide backbone hydroxyls, and (3) the radical crosslinking of pendant vinyl functionalities affording a hydrophilic network. Crosslinking strategies explored include redox initiation and photo initiation, with an effort to adapt the suggested synthesis routes to benign conditions. The different functionalization strategies were shown to influence the resulting gel's properties. Varying the crosslinking media was found to be a strong tool to tune the properties of the gels. Modifications were in all cases verified by means of NMR and FTIR, and the gels were characterized with respect to swelling capacity and rheological parameters. It was shown that by adjusting the synthesis parameters, the resulting properties of the AcGGM gels could be custom-made for a given performance.

Keyword
crosslinking, galactoglucomannan, hemicellulose, hydrogels, polysaccharides, swelling, hemicellulose-based hydrogels, biodegradable polymers, delivery, softwood, water
National Category
Other Materials Engineering
Identifiers
urn:nbn:se:kth:diva-18552 (URN)10.1002/pola.23444 (DOI)000267444200011 ()2-s2.0-67650669939 (Scopus ID)
Note
QC 20100525Available from: 2010-08-05 Created: 2010-08-05 Last updated: 2017-12-12Bibliographically approved

Open Access in DiVA

summary(150 kB)125 downloads
File information
File name SUMMARY01.pdfFile size 150 kBChecksum SHA-512
d86360c0c0fb7b9002feb7324fb3dd7d30b02245f762a895bc53ac77bd6ab07f49ae9f7b4a9036abe3fb2a5160f4a3e40b0860cda482c4def92e491d99ec17a1
Type summaryMimetype application/pdf

Search in DiVA

By author/editor
Voepel, Jens
By organisation
Fibre and Polymer Technology
Other Materials Engineering

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

isbn
urn-nbn

Altmetric score

isbn
urn-nbn
Total: 849 hits
CiteExportLink to record
Permanent link

Direct 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