RESUMO
OBJECTIVE:To develop a HPLC method for determination of tinidazole and chlorhexidine acetate in co-tinidazole gargle.METHODS:Tinidazole and chlorhexidine acetate in co-tinidazole gargle were determined by RP-HPLC with metronidazole as the internal standard.ODS was adopted as stationary phase and acetonitrile-water(35∶65)as mobile phase.The detector was operated at UV254nm.RESULTS:The calibration curve of tinidazole was linear within the concen?tration range of(0.01～0.10)mg/ml(r=0.9999);The calibration curve of chlorhexidine acetate was linear within the con?centration range of(0.01～0.10)mg/ml(r=0.9997).The average recoveries of tinidazole and chlorhexidine were(97.06～102.02)%and(97.21～103.40)%,respectively.The within-day coefficients of variance were(0.20～1.26)%and(0.71～1.11)%,respectively.The between-days coefficients of variance were(0.50～2.06)%and(0.80～2.17)%,respective?ly.CONCLUSION:The method is suitable for determination of preparations containing tinidazole and chlorhexidine acetate.