SANS study on self-assembled structures of glucose-responsive phenylboronate ester-containing diblock copolymer

Block copolymers containing boronic acid-functionalized segments belong to an interesting class of materials that can be potentially used in developing self-regulated insulin delivery systems. Determination of the solution structure of these block copolymers is crucial to understanding their performance. Self-assembled structures of glucose-responsive diblock copolymer, poly(ethyleneglycol)-block-poly[(2-phenylboronate esters-1,3-dioxane-5-ethyl)methylacrylate] (PEG-b-PPBDEMA), in aqueous solution were studied using small-angle neutron scattering (SANS). SANS data suggested that PEG-b-PPBDEMA diblock copolymer with a PEG content of 24 wt.% formed vesicles that responded differently to 0.1% and 0.5 wt.% glucose under physiological conditions. Upon elevation of pH, a shape transition to cylinders was observed. The effect of molarity of the buffer on the stability of the vesicles and micelles was also studied. (C) 2016 Elsevier Ltd. All rights reserved.