Self-assembly and drug delivery studies of pH/thermo-sensitive polyampholytic (A-co-B)-b-C-b-(A-co-B) segmented terpolymers

Abstract

We investigated the behavior of the pH and thermo-responsive poly(2-(diethylamino)ethyl methacrylate-co-methacrylic acid)-b-(ethylene glycol methyl ether methacrylate)-b-poly(2-(diethylamino)ethyl methacrylate-co-methacrylic acid) (P(DEAEMA-co-MAA)-b-PEGMA-b-P(DEAEMA-co-MAA)) triblock terpolymers in aqueous solution by means of static and dynamic light scattering, transmission electron microscopy and rheology. Association phenomena were observed at the isoelectric point region of the polyampholyte outer blocks leading to flower-like micelles and at higher polymer concentrations, to a three dimensional transient micellar network, exhibiting a compex thermo-response thanks to the thermo-sensitivity of the PEGMA middle block. Doxorubicin (DOX) drug was loaded in the terpolymer micelles and drug release studies were performed. Controlled drug delivery could be achieved by tuning pH. The terpolymer micelles exhibited satisfactory cytocompatibility towards human umbilical vein endothelial cells.