Synthesis of PHB-based carrier for drug delivery systems with pH-controlled release

Synthetic route to prepare model PHB-amine conjugate containing hydrolysable imine bond is reported. Short-chain PHB crotonate is converted into PHB glyoxylate via clean and efficient ozonolysis followed by reductive decomposition of peroxidic products with dimethylsulfide. Aldehyde-functionalized PHB is obtained quantitatively without polymer backbone degradation while PHB-amine conjugate is synthesized with very high yield. Release properties of such-prepared conjugate is confirmed in hydrolysis experiment revealing pH-dependent kinetics of amine release. Simplicity of the protocol in conjunction with unique properties of PHB carrier are believed to be powerful tool for development of novel drug conjugates. (C) 2013 Elsevier Ltd. All rights reserved.