[Determination of chlorhexidine acetate in chlorhexidine acetate suppositories by high performance liquid...

A novel method was developed to determine the content of chlorhexidine acetate (CA) in chlorhexidine acetate suppositories by high performance liquid chromatography (HPLC) coupled with hollow fiber membrane solvent microextraction. The sample was extracted with 1.5 mol/L acetic acid solution five times, then a hollow fiber containing n-octanol was placed in the sample solution to perform microextraction for extracting 20 min. The extract was analyzed by HPLC with UV detection at 260 nm. The chromatographic conditions were as following: acetonitrile-redistilled water (29:71, v/v, containing 0.3% triethylamine, pH 3.0) as mobile phase with the flow rate of 1 mL/min. The calibration curve of CA was linear from 0.5 to 16 mg/L. The method recovery was over 98.0% with relative standard deviation less than 4.0%. By using hollow fiber membrane solvent microextraction, the enrichment of 24-fold was achieved. The method is specific, simple, fast, sensitive and suitable for the determination of chlorhexidine acetate.