A method for the detection of trace amounts of nucleophilic functions in aqueous media

摘要

A new process for the detection of trace amounts of pollutants with nucleophilic properties such as thiols, phenols, oximes and amines using isocyanate reactants. Isocyanates are used to react with the nucleophilic functions in aqueous solution to form carbamates, thiocarbamates or urea derivatives which can then be analyzed by HPLC. The procedure comprises three stages:- -addition of the isocyanate, or precursor, to a basic aqueous solution containing the nucleophilic agent(s); - maintenance of the solution, for a few mins. to 2 hs, at a temperature less than 100 deg C; -analysis of the carbamate, thiocarbamate or urea obtained. The isocyanate can be formed in situ from a nitrosourea of general formula R1NHCON(NO)R2 (I). An Independent claim is also included for a test kit which comprises: (1) A quantity of N-2,4 dintrobenzoyl N1(N-2-chloroethyl)-N-nitroso)carbamoyl-1,4-diamonobutane, as a pure 99% powder; (2) A solution of 99% triethylamine; (3) A standard pure histamine derivative with NMR and UV spectra; and (4) solutions of the histamine standard in acetonitrile for calibration of the system.