Polymeric micelles based on amphiphilic scorpion-like macromolecules: Novel carriers for water-insoluble drugs

Purpose. The objective was to evaluate amphiphilic scorpion-like macromolecules (AScMs) as drug carriers for hydrophobic drugs. Methods. Indomethacin (IMC) was incorporated into two AScM micelleS (M12P5 and M12P2) by the O/W emulsion technique. The influences of IMC:polymer feed ratio and molecular weight of the hydrophilic block of AScMs on the micelle size, IMC entrapment efficiency and release behavior were investigated. Furthermore, cytotoxicity of the AScMs was evaluated with human umbilical vein endothelial cells (HUVEC). Results. The maximal IMC entrapment efficiency in M12P5 and M12P2 micelles (72.3 and 20.2%, respectively) was obtained at ratios of 0.1 to 1 for indomethacin:polymer. The sizes of IMC-loaded M12P5 and M12P2 polymeric micelles were <20 nm with a narrow size distribution. In vitro release studies revealed that IMC released from M12P5 and M12P2 polymeric micelles showed sustained release behavior during the 24 h of experiment. Additionally, M12P5 and M12P2 polymeric micelles did not induce remarkable cytotoxicity against HUVEC cells at concentrations up to 1 and 0.5 mM, respectively. Conclusion. The amphiphilic scorpion-like macromolecules may be useful as novel drug carriers because of their small size, ability to encapsulate hydrophobic drugs and release them in a sustained manner as well as low cytotoxicity.