Physicochemical characteristics of poly(2-ethyl-2-oxazoline)/poly(epsilon-caprolactone) block copolymer micelles in water

Abstract

Polymeric micelles have found numerous applications in the area of biomedical engineering, including the delivery of bioactive molecules. Block copolymers, typical polymeric amphiphiles, form micelles in aqueous phases containing a hydrophobic inner core and hydrophilic outer shell. The unique characteristics of polymeric micelles are mainly controlled by the chemical structure and length of the hydrophilic and hydrophobic blocks. In this study we hypothesized that the solubility parameter values of the organic solvents typically used to dissolve the polymeric amphiphiles and eventually removed from an aqueous phase could significantly influence the characteristics of the resultant micelles in an aqueous phase. Poly(2-ethyl-2-oxazoline)-b-poly(epsilon-caprolactone) (PEtOz-b-PCL) was synthesized and dissolved in various organic solvents to prepare micelles in water. Their various physicochemical characteristics were investigated by the dynamic light scattering method and fluorescence spectroscopy.