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Bio-degradable/bio-compatible poly(lactide-co-glycidyl methacrylate), P(LA-co-GMA), a copolymer has been synthesized. The material contains curable C C groups, which enable its self-curing and grafting reactions with other vinyl monomers. The copolymer was grafted with a pH-responsive polyacrylamide (PAAm), by UV-assisted reactions using acrylamide (AAm) and N,N′-methylene bisacrylamide monomers, and various photoinitiator systems. The original copolymer and its partially-cured counterpart were employed in the grafting reaction. Chemical structures and properties of the resulting materials were characterized. Standard quantitative analysis techniques for measurement of the grafted AAm content and the degree of C C conversion have been developed by 1H NMR and FTIR spectroscopy. FTIR offers more advantages, in terms of non-destructive analysis, ease of operation, and lower cost of analysis. The results show that the grafted products from pre-cured P(LA-co-GMA) copolymers contain higher grafted AAm contents than their uncured counterparts. The highest grafted AAm content was obtained by using benzophenone (BP) as an initiator, while camphorquinone (CQ) led to the lowest content. In contrast, the degree of C C conversion of the copolymer from the two initiator systems shows a reverse trend. These amphiphilic and pH-responsive grafted copolymers with tunable AAm contents have a high potential for use in various applications, especially in biomedical and environmental fields.

Summary The Bombyx mori silk fibroin (SF) has recently received much attention as promising hydrogel matrices due to its biocompatibility, hydrophilicity and good permeability. Beside these, porous SF is too brittle in its dry state that does not provide sufficient strength for practical use. To overcome this drawback, semi-interpenetrating networks of SF were synthesized by a redox-initiated reaction using poly(ethylene glycol) diacrylate (PEGa) as a precursor to form a primary network. Various hydrogel properties, including swelling ability, gelation kinetics, morphology and drug release, were evaluated through both physical and spectroscopic techniques. For all hydrogels, the gelation time, sol-gel fraction and equilibrium water content (EWC) were found to decrease with the increasing of PEGa content. Moreover, a sustained delivery of a model compound, Rhodamine B, was also observed. This could be explained in terms of tighter interconnected network and the retardation effects mediated by SF. The proposed method had thus, demonstrated its potential use to improve performance of silk-based materials for drug delivery applications.