Effect of temperature on the association behavior in aqueous mixtures of an oppositely charged amphiphilic block copolymer and bile salt
The association in aqueous mixtures of a thermoresponsive cationic diblock copolymer composed of poly(N-isopropylacrylamide) (PNIPAM) and poly(3-acrylamidopropyl)-trimethylammonium-chloride (PAMPTMA(+)) and the oppositely charged bile salt sodium deoxycholate (NaDC) is investigated at different compositions by light and X-ray scattering, calorimetry, and electrophoretic mobility measurements. Clouding reveals aggregation upon heating. The addition of NaDC to the copolymer solution lowers the temperature of the transition and increases its cooperativity.