Simultaneous Determination of Disodium Cantharidinate and Vitamin B₆ in Disodium Cantharidinate and Vitamin B₆ Injection by HPLC

OBJECTIVE To establish method for simultaneous determination of disodium cantharidinate and vitamin B₆ in Disodium Cantharidinate and Vitamin B₆ injection. METHODS HPLC was performed on a Syncronis C₁₈ column(250 mm×4.6 mm, 5 μm) using the gradient 0.02 mol·L^-1 potassium phosphate monobasic solution(adjust pH to 2.6 with H₃PO₄)(A)-acetonitrile(B) at the 1.0 mL·min^-1 flow rate as mobile phase. The column temperature was 30℃ and the detection wavelengths were 193 nm and 290 nm(wavelength switching). RESULTS The linear regression equation of disodium cantharidinate was Y=1.926X+0.010(r=0.999 7); the linear range was 0.064 6-0.322 8 mg·mL^-1 with the average recovery of 98.9% and the RSD of 1.2%(n=9). The linear regression equation of vitamin B₆ was Y=24.153X+0.670(r=0.999 9); the linear range was 0.535 9-2.679 7 mg·mL^-1 with the average recovery of 100.2% and the RSD of 1.0%(n=9). The RSD values for the instrument precision, stability and repeatability were all <2.0%. CONCLUSION The established HPLC method appears to be accurate and reproducible, which can be used for the quality control of Disodium Cantharidinate and Vitamin B₆ injection.