| 초록 |
Micellization of biologically active substances is a great phenomenon that increases the bioavailability of lipophilic drugs. Currently poly(ethylene glycol)-b-poly(D,L-lactide-co-glycolide) diblock copolymer was used as a candidate for micellization, but these micelles are very unstable. Thus to overcome this limitation, a pH-sensitive moiety was introduced into the block copolymer, and applicable to target drug delivery. The block copolymer was synthesized by ring opening polymerization of D,L-lactide and glycolide using poly(ethylene glycol) mono methyl ether in the presence of stannuous octoate as a catalyst. The pH sensitive moiety was synthesized by the structure modification of sulfisomidine (pKa 7.4). The structure of sulfisomidine was modified using bromoacetic acid to have carboxymethylated structure, which was used for synthesis of pH-sensitive block copolymer. This copolymer was checked for micellization-demicellization behavior, which was governed by fluorescence spectrometer. The pH-responsive polymer micelles may find more stability and targeting behavior than the block copolymer micelles, which leads to more impetus on ongoing research in drug delivery system. |
