Rapid quantitative determination of the sulphate groups of dextran sulphate

Abstract

We describe a method for the determination of sulphate groups of dextran sulphate by precipitation with a standard solution of an organic amine compound. The method used to determine the dosage equivalence point is new and based on the measurement of the medium dielectric permittivity during titration. The method has been compared to a previous and classical procedure based on sample combustion followed by coulometric titration of the sulphur dioxide released. This new method is easy, rapid, can be automatized and presents a limit of detection of 10-4 M (expressed in sulphate concentration). In addition, this method has applications in raw material control as well as in formulation. © 1995.