High-performance liquid chromatographic assay for partially nitrated glycerins in nitroglycerin.

A high-performance liquid chromatographic method for determining the concentration of mononitroglycerins and dinitroglycerins in the commonly used pharmaceutical raw material nitroglycerin (10% w/w) on lactose USP is presented. A coefficient of variation of less than 5% for the partially nitrated glycerins was achieved over the range examined (0-4.0 micrograms/mg). Thirteen lots of raw material were examined and found to contain a total of less than 0.13% w/w partially nitrated glycerins. A variable wavelength detector (lambda = 218 nm) and a microphenyl column were employed. The mobile phase was acetonitrile-water (36:64) pumped at 2 ml/min. The internal standard was isosorbide dinitrate. Total analysis time was 12 min.