Simultaneous Determination of Related Substances and Chlorhexidine Acetate in Tetracaine Hydrochloride Jelly by HPLC

OBJECTIVE To establish an HPLC method to determine the content of related substances and chlorhexidine acetate in tetracaine hydrochloride jelly. METHODS Kromasil C₁₈ column(150 mm×4.6 mm, 5 μm) was used. The mobile phase was phosphate buffer-acetonitrile with gradient elution. The column temperature was 35 ℃. The flow rate was 1.0 mL·min^-1. Related substances and chlorhexidine acetate were detected at 300 nm and 258 nm, respectively. RESULTS Tetracaine hydrochloride was completely separated from impurities. The calibration curves of tetracaine, aminobenzoic acid and butyl of aminobenzoic acid were linear in the range of 0.11-7.93, 0.06-4.38, 0.11-7.91 μg·mL^-1(r=0.999 9-1.000 0), respectively. The average recovery of chlorhexidine acetate was 100.2%, RSD=1.0%(n=9). CONCLUSION This method is simple, specific, sensitive, accurate and can be applied to control the related substances and chlorhexidine acetate in tetracaine hydrochloride jelly.