Purity analysis method of 5,5'-bistetrazole-1,1'-dyhydroxy dihydrate

Analysis conditions of 5,5'-bistetrazole-1,1'-dyhydroxy dehydrate (BTO) by high performance liquid chromatography (HPLC) were determined as follows: UV detection wavelength 213 nm, reversed phase column (SinoChrom ODS-BP, 4.6 mm×200 mm, 5 μm), binary mobile phase acetonitrile and water (volume ratio of 30/70) with flow rate of 1.0 mL·min^-1 at column temperature of 25℃. External standard method was used to analyze BTO standard solution. Results show that there is a good linearity between peak height(h) and concentration(c) from 0.12 mg·mL^-1 to 0.60 mg·mL^-1. The linear equation is h=573.78c-1.18 with linear correlation coefficient of 0.9998. The relative standard deviation is 0.48%-1.00% and the average recovery is 98.10%-100.64%, indicating that the method is accurate and sensitive and can be applied in the determination of BTO purity.