Journal article
Synthesis and recovery characteristics of branched and grafted PNIPAAm–PEG hydrogels for the development of an injectable load-bearing nucleus pulposus replacement
Acta biomaterialia, v 6(4), pp 1319-1328
2010
PMID: 19837195
Featured in Collection : UN Sustainable Development Goals @ Drexel
Abstract
A family of injectable poly(
N-isopropyl acrylamide) (PNIPAAm) copolymer hydrogels has been fabricated in order to tune mechanical properties to support load-bearing function and dimensional recovery for possible use as load-bearing medical devices, such as a nucleus pulposus replacement for the intervertebral disc. PNIPAAm–polyethylene glycol (PEG) copolymers were synthesized with varying hydrophilic PEG concentrations as grafted or branched structures to enhance dimensional recovery of the materials. Polymerizations were confirmed with attenuated total reflectance-Fourier transform infrared spectroscopy and proton nuclear magnetic resonance spectroscopy studies. Incorporation of PEG was effective in raising water content of pure PNIPAAm hydrogels (29.3% water for pure PNIPAAm vs. 47.7% for PEG branches and 39.5% for PEG grafts). PNIPAAm with 7% grafted as well as 7% branched PEG had significantly reduced compressive modulus compared to that of pure PNIPAAm. Initially recovered compressive strain was significantly increased for 7% PEG branches after pre-testing immersion in PBS for up to 33
days, while 7% PEG grafts decreased this value. Sample height recovery for pure PNIPAAm was limited to 31.6%, while PNIPAAm with 7% branches was increased to 71.3%. When mechanically tested samples were allowed to recover without load over 30
min, each composition was able to significantly recover height, indicating that the time to recovery is slower than the unloading rates typically used in testing. While the incorporation of hydrophilic PEG was expected to alter the mechanical behavior of the hydrogels, only the branched form was able to significantly enhance dimensional recovery.
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Details
- Title
- Synthesis and recovery characteristics of branched and grafted PNIPAAm–PEG hydrogels for the development of an injectable load-bearing nucleus pulposus replacement
- Creators
- Jonathan D Thomas - Department of Materials Science and Engineering, Drexel University, Philadelphia, PA 19104, USAGarland Fussell - Synthes Spine, 1230 Wilson Dr., West Chester, PA 19380, USASumona Sarkar - School of Biomedical Engineering, Science and Health Systems, Drexel University, Philadelphia, PA 19104, USAAnthony M Lowman - Department of Chemical and Biological Engineering, Drexel University, Philadelphia, PA 19104, USAMichele Marcolongo - Department of Materials Science and Engineering, Drexel University, Philadelphia, PA 19104, USA
- Publication Details
- Acta biomaterialia, v 6(4), pp 1319-1328
- Publisher
- Elsevier
- Resource Type
- Journal article
- Language
- English
- Web of Science ID
- WOS:000276013500012
- Scopus ID
- 2-s2.0-76949100245
- Other Identifier
- 991014877860704721
UN Sustainable Development Goals (SDGs)
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InCites Highlights
Data related to this publication, from InCites Benchmarking & Analytics tool:
- Web of Science research areas
- Engineering, Biomedical
- Materials Science, Biomaterials