MODIFICATION OF PREPARATION OF DIAZOMETHANE FOR METHYL ESTERIFICATION OF ENVIRONMENTAL-SAMPLES ANALYSIS BY GAS-CHROMATOGRAPHY

A modified procedure is described for the preparation of diazomethane for methyl esterification of environmental samples analysis by gas chromatography. Presently, the U.S. Environmental Protection Agency recommends the bubbler method and the Diazald kit method for methyl esterification of acidic herbicides and other related compounds. The proposed modified procedure will be more convenient and safer to operate than either of these two methods, thus eliminating their tedious nature and potential hazards. In this study, the Aldrich MNNG (N-methyl-N'-nitro-N-nitrosoguanidine) Diazomethane Kit is modified. Diazald is the reagent used instead of MNNG because of its large scale production of diazomethane, fast reaction time, safety, and stability. The whole esterification procedure takes about 40 minutes. It can simultaneously esterify many samples and it yields consistent results.