NIPAAm-containing amphiphilic block copolymers with tailored LCST: Aggregation behavior, cytotoxicity and evaluation as carriers of indomethacin, tetracycline and doxorubicin Academic Article in Scopus uri icon

abstract

  • © 2019, © 2019 Taylor & Francis Group, LLC.Nanocarriers based on amphiphilic block copolymers, with tailored temperature and pH responsiveness, were prepared. The hydrophilic blocks consist of temperature-sensitive [N-isopropylacrylamide (NIPAAm)] or NIPAAm plus pH-sensitive units [5-methacryloyloxy pentatonic acid (5MPA) or 4-methacryloyloxy benzoic acid (4MBA)], while the hydrophobic block is composed of n-hexyl acrylate (HA) or styrene (ST). Particle sizes were within the suitable range for the desired application (30¿182 nm). Drug loading was achieved via an organic solvent-free method and a THF-buffer method leading to drug loadings of indomethacin, tetracycline and doxorubicin of up to 11, 11 and 60 wt%, respectively. In vitro release kinetics were performed under simulated physiological conditions (pH 7.4 and 37 °C; pH 6.0 and 40 °C) and show differences depending on the copolymer composition. The average kinetic data were well fitted to the mathematical model of Peppas. NIPAAm-containing copolymers were slight or non-cytotoxic for rat primary hepatocytes at concentrations less than 200 µg mL¿1. Some of the polymeric aggregates prepared may find application as pharmaceutical carriers.

publication date

  • August 3, 2019