SODIUM TETRA(N-PROPYL)BORATE - A NOVEL AQUEOUS IN-SITU DERIVATIZATIONREAGENT FOR THE SIMULTANEOUS DETERMINATION OF ORGANOMERCURY, ORGANOLEAD AND ORGANOTIN COMPOUNDS WITH CAPILLARY GAS-CHROMATOGRAPHY INDUCTIVELY-COUPLED PLASMA-MASS SPECTROMETRY

The versatility of sodium tetra(n-propyl)borate, NaBPr4, as aqueous in situ derivatization reagent for organometallic compounds is demonstra ted. With this new derivatization reagent it is now possible to deriva tize the important ethyl derivatives of lead and mercury which until n ow had to be derivatized by Grignard alkylation or hydride generation. The synthesis of NaBPr4 is described in detail. Derivatization parame ters such as pH, reaction time, amount of reagent and stability of the aqueous NaBPr4 solution were investigated, Different organometallic c ompounds of tin, mercury and lead were simultaneously determined by an inductively coupled plasma mass spectrometer coupled to the capillary GC system using a laboratory-developed interface. Good linearity was obtained for all components with detection limits in the ng/l range (w ithout preconcentration). The reproducibility of the complete procedur e, i.e. derivatization, extraction and injection, is better than 10% R .S.D, The analysis of the PACS-1 Reference Material after derivatizati on with NaBPr4 showed the accuracy of this method. (C) 1998 Elsevier S cience B.V.