pH-responsive stealth micelles composed of cholesterol-modified PLA as a nano-carrier for controlled drug release

摘要: Present research is a preliminary report on the novel pH-responsive micelles based an amphiphilic brush copolymer P(PEGMA)-b-P(DMAEMA-co-CPLA- MA) used as promising drug carrier. The was synthesized using cholesteryl poly(L-lactic acid) methacrylate (CPLAMA), poly(ethylene glycol) mono- methyl ether (PEGMA) and 2-(dimethyl- amino)ethyl (DMAEMA) with appropriate hydrophobic/hydrophilic ratios via atom transfer radical polymerization. compositions were determined by 1 H NMR. self-assembled into nano-scale capable of encap- sulating hydrophobic model naproxen in their cores aqueous solutions. pH sensitivity self-assembly behaviors studied UV-vis transmittance, fluorescence spectroscopy, trans- mission electron microscopy (TEM) dynamic light scattering. results showed that had high responsivity phase transition around 6.2. critical micelle concentrations at 6.5 found about 2.4 mg L -1 . stable small obtained 5.5-6.5. Upon increasing higher than 7, single further assembled micellar aggregates. TEM images are spherical shape mean diameter 152 nm In vitro release study naproxen-loaded 44 % loading effi- ciency 8 capacity performed dialysis method phosphate-buffered solution 37 C. Release implied proposed could produce nano-carriers controllable target sites (pH 5.5-7).