Molecular Recognition Properties of Biodegradable Photo-Crosslinked Network Based on Poly(lactic acid) and Poly(ethylene glycol)

Molecular recognition properties of biodegradable photo-crosslinked networks based on poly(lactic acid) (PLA) and poly(ethylene glycol) (PEG) were evaluated. A biodegradable crosslinker, diacrylated PLA-PEG-PLA triblock copolymer was synthesized through the ring opening polymerization of D,L-lactide using hydrophilic PEG as a macroinitiator, followed by diacrylation of the end groups for the introduction of the polymerizable vinyl groups. The synthesis of acrylate end-capped macromers was characterized using FTIR and H-1 NMR spectroscopic techniques. These macromers were used to prepare biodegradable molecularly imprinted polymers (MIPs) by photopolymerization with methacrylic acid (functional monomer) and theophylline (model template). Various polymers were prepared by changing the ratio of functional monomer to the crosslinking agent and the macromer concentration in order to obtain optimum conditions for MIP synthesis. The theophylline-imprinted polymer demonstrated higher rebinding capacity to theophylline than its corresponding non-imprinted polymer (NIP) and selectivity for theophylline over caffeine (similar structure molecule), suggesting that these polymer networks can potentially be used as biodegradable materials with specific molecular recognition properties.