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
Synthesis and Characterization of Self-Assembling Low Molecular Weight Copolymers for Bioengineering Applications
KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Polymer Technology.
2013 (English)Licentiate thesis, comprehensive summary (Other academic)
Abstract [en]

The constant need for improved biomedical materials and the interest in producing materials with similar properties to the extracellular matrix in different tissues has resulted in increasing interest in research on hydrogels. Over the last decade self-assembling copolymers have been of particular interest since they form hydrogels in response to external stimuli such as temperature. In this thesis, two self-assembling low molecular weight copolymers; poly(L-lactide-co-glycolide) grafted with poly(ethylene glycol) methyl ether (PLGA-g-MPEG) and poly(L-lysine-co-L-alanine) (poly(Lys-co-Ala)) were synthesized for possible bioengineering applications. Their chemical structure and composition was analysed by nuclear magnetic resonance spectroscopy (NMR) and matrix assisted laser desorption ionization time of flight mass spectrometry (MALDI-TOF-MS). The results showed that low molecular weight PLGA-g-MPEG and poly(Lys-co-Ala) were successfully obtained.

PLGA-g-MPEG hydrogels were formed at 37°C, within 1 minute, at a pH between 6-7 and had a functional life of one month. The block cooligopeptides of L-lysine and L-alanine formed cubic, hexagonal and hollow crystals in low pH and irregularly shaped crystals in at pH 7, while plate-like crystals were formed at both pH 3 and 7 form the random cooligopeptides. Evaluation of the properties of the low molecular weight copolymers, such as pH, functional life and crystalline morphology, revealed that the chemical composition and solvent composition strongly affects their self-assembling properties.

These synthesized low molecular weight copolymers showed promise results for use as material in biomedical applications. Areas of potential use for these materials include bioengineered hierarchical scaffold material facilitating sequential release of growth factors, for example in bone tissue engineering, and as materials for encapsulated drug delivery.

Place, publisher, year, edition, pages
Stockholm: KTH Royal Institute of Technology, 2013. , 44 p.
Series
Trita-CHE-Report, ISSN 1654-1081 ; 2013:46
Keyword [en]
cooligomers, bioengineerng applications, polymer synthesis
National Category
Polymer Chemistry
Identifiers
URN: urn:nbn:se:kth:diva-136843ISBN: 978-91-7501-910-9 (print)OAI: oai:DiVA.org:kth-136843DiVA: diva2:677342
Presentation
2013-12-12, K2, Teknikringen 28, KTH, Stockholm, 10:00 (English)
Opponent
Supervisors
Note

QC 20131210

Available from: 2013-12-10 Created: 2013-12-09 Last updated: 2013-12-10Bibliographically approved
List of papers
1. Mapping the synthesis and the impact of low molecular weight PLGA-g-PEG on sol-gel properties to design hierarchical porous scaffolds
Open this publication in new window or tab >>Mapping the synthesis and the impact of low molecular weight PLGA-g-PEG on sol-gel properties to design hierarchical porous scaffolds
2013 (English)In: Journal of polymer research, ISSN 1022-9760, E-ISSN 1572-8935, Vol. 21, no 1, 337- p.Article in journal (Refereed) Published
Abstract [en]

Bone morphogenetic protein 2 (BMP-2)-functionalized poly(l-lactide-co-epsilon-caprolactone) (PLCL) porous scaffolds have shown promising results in bone tissue regeneration studies. It is believed that even better results are achieved by hierarchical porous scaffolds and a designed sequential release of growth factors. We therefore synthesized (l-lactide-co-glycolide)-g-poly(ethylene glycol) (PLGA-g-PEG) oligomers which could be injected into PLCL porous scaffolds. They were synthesized by ring-opening polymerization and carefully characterized by nuclear magnetic resonance spectroscopy (NMR), matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF-MS), and size exclusion chromatography (SEC). The sol-gel transition temperature, pH, and functional life were determined and correlated with the molecular structure of PLGA-g-PEG. We found that low molecular weight PLGA-g-PEG was obtained and poly(l-lactide-co-glycolide-co-poly(ethylene glycol) methyl ether) (PLGA-MPEG) appeared to contribute to gelation. It was possible to design a system that formed a hydrogel within 1 min at 37 A degrees C with a pH between 6 and 7 and with a functional life of around 1 month. These low molecular weight thermosensitive PLGA-g-PEG oligomers, which can be injected into PLCL scaffolds, appear promising for bone tissue engineering applications.

Keyword
Thermosensitive gel, PLGA-g-PEG, Porous scaffolds, Tissue engineering, Degradable polymers
National Category
Polymer Technologies
Identifiers
urn:nbn:se:kth:diva-136995 (URN)10.1007/s10965-013-0337-8 (DOI)000328848400001 ()
Note

QC 20140121. Updated from manuscript to article in journal.

Available from: 2013-12-10 Created: 2013-12-10 Last updated: 2017-12-06Bibliographically approved
2. Short one-pot chemo-enzymatic synthesis of L-lysine and L-alanine diblock copolypeptides
Open this publication in new window or tab >>Short one-pot chemo-enzymatic synthesis of L-lysine and L-alanine diblock copolypeptides
(English)Manuscript (preprint) (Other academic)
Identifiers
urn:nbn:se:kth:diva-136997 (URN)
Note

QS 2013

Available from: 2013-12-10 Created: 2013-12-10 Last updated: 2013-12-10Bibliographically approved

Open Access in DiVA

No full text

Search in DiVA

By author/editor
Fagerland, Jenny
By organisation
Polymer Technology
Polymer Chemistry

Search outside of DiVA

GoogleGoogle Scholar

isbn
urn-nbn

Altmetric score

isbn
urn-nbn
Total: 385 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