Comparison of Analytical Methods for Related Substances of Sisomicin Sulfate Injection / 中国药学杂志

ABSTRACT

OBJECTIVE: To establish an HPLC-PAD method to determine the related substances of sisomicin sulfate injection and compare with the statutory method. METHODS: IonPac AMG C18(4.0 mm×150 mm, 3 μm)chromatographic column was used with acetonitrile-0.1 mol·L-1 trifluoroacetic acid (containing 0.025% of pentafluoropropionic acid, 5 mL of 50% NaOH solution without carbonate, pH of the aqueous solution adjusted to 2.3 with 50% NaOH solution.)as mobile phase at a flow rate of 0.7 mL·min-1. NaOH solution of 0.76 mol·L-1 was added post column at a flow rate of 0.35 mL·min-1. The column temperature was maintaine at 30 ℃. PAD detector was operated with the cell temperature set at 35 ℃. The working electrode was a gold electrode (diameter of 3 mm)and a quadruple-potential waveform was selected as detection waveform. The reference electrode was Ag/AgCl, the detection potential was four potential. The determination result of the related substances of sisomicin sulfate injection was compared with that of the statutory method. RESULTS: The peaks of sisomicin sulfate, gentamicin C1a and netilmicin could be completely separated, and other impurities could also be effectively separated. The blank sample had no interferences. The LOD and LOQ of etimicin were found to be 2 and 6 ng respectively, and the RSD of precision test (n=6) was 0.9%. Paired-samples t-test showed significance levels of P=0.034, P=0.364 and P=0.605 for total amount of impurities (%), the biggest single impurity (%)and content (%)respectively between the statutory method and the method of HPLC-PAD. CONCLUSION: Compared with the statutory method, this HPLC-PAD method shows higher sensitivity, and is accurate and reliable. It can be applied to the determination of related substances in sisomicin sulfate injection.