Self-assembled, thermoresponsive micelles based on triblock PMMA-b-PNIPAAm-b-PMMA copolymer for drug delivery

A novel thermosensitive amphiphilic ABA triblock poly(methyl methacrylate)- b -poly( N -isopropylacrylamide)- b -poly(methyl methacrylate) copolymer (PMMA- b -PNIPAAm- b -PMMA) comprised of two hydrophobic PMMA segments and one hydrophilic PNIPAAm segment was designed and synthesized. The structure of the copolymer was characterized by FT-IR, 1 HNMR, and GPC analysis. The cytotoxicity study showed that the PMMA- b -PNIPAAm- b -PMMA copolymer exhibited low cytotoxicity. The copolymer was capable of self-assembling into micelles in water and demonstrated temperature sensitivity at around 34.5 °C. Transmission electron microscopy (TEM) showed that the micelles exhibit nanosized spherical morphology within a size range of 60 nm with a critical micellar concentration (CMC) at 10 mg l −1 . The drug-loading PMMA- b -PNIPAAm- b -PMMA micelles showed thermosensitive-controlled release which indicates the potential of PMMA- b -PNIPAAm- b -PMMA micelles as drug carriers.