Turbidimetric determination of chlorhexidine using flow injection analysis

Abstract

A study of some chlorhexidine-dye and chlorhexidine-Cu^II systems was carried out in order to determine the best precipitate for the turbidimetric determination of chlorhexidine using flow injection analysis (FIA). The reagent selected was thymol blue, which gives an orange solid (1 : 2 stoicheiometry). The chemical and FIA variables were established using the modified simplex method and the calibration graph was linear over the concentration range 10.5–63.0 µg ml^–1 of chlorhexidine. Some interfering substances were also investigated.