Influence of free chains on the swelling pressure of PEG-HEMA and dex-HEMA hydrogels
Autor: | Kevin Braeckmans, Barbara Stubbe, Joseph Demeester, Ferenc Horkay, S.C. De Smedt, T.G. Van Thienen |
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Rok vydání: | 2007 |
Předmět: |
Kinetics
Pharmaceutical Science Biocompatible Materials macromolecular substances Dosage form Polyethylene Glycols chemistry.chemical_compound Polymethacrylic Acids Osmotic Pressure PEG ratio Polymer chemistry medicine Technology Pharmaceutical Osmotic pressure Drug Carriers Molecular Structure technology industry and agriculture Water Dextrans Hydrogels Molecular Weight Dextran chemistry Self-healing hydrogels Methacrylates Swelling medicine.symptom Drug carrier |
Zdroj: | International Journal of Pharmaceutics. 337:31-39 |
ISSN: | 0378-5173 |
Popis: | Insight in the osmotic behavior of degrading hydrogels is of great importance in the design of biodegradable hydrogels for biomedical applications. This study compares the degradation behavior of PEG-HEMA (hydroxyethylmethacrylated polyethylene glycol) and dex-HEMA (hydroxyethylmethacrylated dextran) hydrogels. The degradation of PEG-HEMA gels takes several months to over a year, while that of dex-HEMA gels takes only days or weeks. The faster degradation kinetics of dex-HEMA networks can be attributed to stabilization of the keto-enol form by hydroxyl groups. Upon degradation of PEG-HEMA and dex-HEMA hydrogels, respectively, free PEG and free dextran chains are produced. We investigated the effect of unattached PEG and dextran chains on the swelling pressure of the degrading gels. It is found that low molecular weight free chains significantly increase the swelling pressure. However, the contribution of higher molecular weight free chains (M(w)>10 kDa) is similar to that of the network chains. |
Databáze: | OpenAIRE |
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