Synthesis and physicochemical analysis of temperature and pH-responsive polymersomes using PEG-b-PDMAEMA copolymers

Amphiphilic block copolymers have a unique ability to self-organize into various nanostructures, including polymersomes, which are vesicular aggregates with promising applications in drug delivery, diagnostics, and nanoreactors, due to their capacity to encapsulate both hydrophilic and hydrophobic substances. Recently, smart polymersomes responsive to environmental stimuli such as temperature and pH have attracted increasing interest, especially for biomedical applications. Among temperature-responsive polymers, the dual-responsive behavior of poly(2-(dimethylamino)ethyl methacrylate) (PDMAEMA) offers versatility, though its application in polymersome systems remains limited. In this study, temperature- and pH-responsive polymersomes were developed via the self-assembly of PEG-b-PDMAEMA copolymers synthesized by atom transfer radical polymerization (ATRP). The lower critical solution temperature (LCST) of the copolymers was characterized using turbidimetric analysis, while their morphology was defined using transmission electron microscopy (TEM). The effects of molecular weight, copolymer concentration, and pH on the self-assembly and polymersome formation behaviors of the block copolymer was systematically evaluated. This study represents the first comprehensive investigation into the formation of temperature- and pH-responsive polymersomes from PEG-b-PDMAEMA, providing new insights into the design of multifunctional polymeric nanocarriers.