Determination of methyl bromide at sub ppm levels in finished pharmaceutical product by gas chromatography

Methyl Bromide is a volatile organohalide well known for its genotoxic properties. Due to its genotoxic nature, health authorities (regulatory bodies) across the globe require that it be kept well within stringent limits in active pharmaceutical ingredients and finished pharmaceutical products. A variety of techniques like HPLC with derivatization, GC with mass detection and GC with atomic emission detection have been employed in the past as well as is currently in use by researchers across the globe for quantitative determination of Methyl Bromide. Although several methods are available in various literatures it may not be feasible to use those methods due to the requirement of highly sophisticated instruments like Mass Detector or due to high cost of analysis or due to poor reproducibility and cumbersome methodology. A sensitive and accurate direct gas chromatographic method was developed using Electron Capture Detector (ECD). In this method Methyl Bromide was well separated from Isopropyl Bromide. The detection limit and quantitation limit were established at 0.015 and 0.0375 ppm respectively during the successful validation of the method. The proposed method was found to be Precise, Specific, Linear, Rugged and Robust.