Polyelectro. lyte Complex of Carboxymethyl-dextran with 2-(Diethylamino)ethyl-dextran Hydrochloride

Abstract

Water-insoluble precipitates were obtained by mixing carboxymethyl-dextran solution(CMD) with 2-(diethylamino)ethyl-dextran, hydrochloride solution (EA) having three groups of diffe rent basicity at different pH values.
The nitrogen contents which describe the molar ratios of COOH(CMD)/N(EA) in each polyelectrolyte complex(PEC) were determined to be 2.01-3.93. It was found that the mixing ratio CMD/EA and pH had remarkable effect on the composition of PEC produced.
On the basis of the studies on IR spectra, elemental analysis, despite each PEC was made of the same EA and CMD, elution of CMD from PEC and solubility of PEC were found to depend upon pH and the structure and the molecular conformation of PEC formed at higher pH were found to differ from those formed at lower pH.
It seemed that the degrees of dissociation and conformations of CMD and EA changed with hydrogen ion concentration.