Determination of Gentamicin C Components and Related Substances Respectively by HPLC with Post Col-umn-derivatization and Electrochemical Detection / 中国药师

ABSTRACT

Objective:To establish an HPLC coupled with post column derivatization method for the determination of gentamicin C components and the related substances based on the latest European Pharmacopeia and compare with the electrochemical method. Methods:A Hydrophilic C18(250 mm ×4.6 mm, 5 μm)column was used with acetonitrile-50 mmol·L-1 sodium hydroxide solution ( pH 2. 6) containing 0. 7% trifluoroacetic acid and 0. 025% pentafluoropropanoic acid (1. 5∶98. 5) as the mobile phase. The temper-ature of post-column reaction was set at 30℃, and the samples were detected by a fluorescence detector withλex of 340nm andλem of 430nm. A pulsed amperometric detector (PAD) was applied in the electrochemical method with golden working electrode in a four-po-tential working mode. Results: According to the results of the two detection methods, the linear range of C1a , C2 , C2a and C1 was 5.82-233.00,6.92-277.00,4.00-160.00and6.23-249.00 μg·ml-1(r >0.9993) , respectively. The limit of detection and quantization were 0. 92-3. 28ng and 1. 37-5. 19ng, respectively. Conclusion:There is no significant difference between the determina-tion results of the two methods.