1. A validated NP – HPLC Method for the determination of formic acid in pharmaceutical excipient imidurea

A sensitive and specific normal phase high performance liquid chromatography (NP-HPLC) method with UV detection has been developed and validated for the quantification of formic acid in pharmaceutical excipient imidurea. The chromatographic separation was carried out on a Hypersil Silica 250 x 4.6 mm, 5μ (Thermo Electron Corporation, USA) with a flow rate of 0.5 mL/min and the column temperature was maintained at 30°C. The mobile phase consisted of n-hexane-isopropyl alcohol-trifluoroacetic acid (900:100:0.5, v/v/v). The samples were injected with an injection volume of 20 μL and detection was accomplished by a variable wavelength UV detector at 230 nm. The retention time of formic acid was about 8.9 min. The method was linear over the range of 331- 7500 μg/mL for formic acid with a correlation of 0.9928. The limit of detection and limit of quantification were 109 and 331 μg/mL respectively. The present method may be applicable for the detection of formic acid in different pharmaceutical product as well.