Microwave-Assisted Photochemical Reactor for the Online Oxidative Decomposition and Determination of p-Hydroxymercurybenzoate and Its Thiolic Complexes by Cold Vapor Generation Atomic Fluorescence Detection
Authors: Angeli V., Ferrari C., Longo I., Onor M., D’Ulivo A., Bramanti E.
Autors Affiliation: Consiglio Nazionale delle Ricerche, Istituto di Chimica dei Composti OrganoMetallici, Area di Ricerca, Via G. Moruzzi 1 56124 Pisa, Italy; Consiglio Nazionale delle Ricerche, Istituto Nazionale di Ottica, UOS PISA, Area di Ricerca, Via G. Moruzzi 1, 56124 Pisa, Italy
Abstract: We developed a photochemical method for the online oxidation of p-hydroxymercurybenzoate (PHMB), an organic mercury species widely used for mercaptan and thiolic compound labeling. The method is based on a fully integrated online UV/microwave (MW) photochemical reactor for the digestion of PHMB, followed by cold vapor generation atomic fluorescence spectrometry (CVG-AFS) detection. The MW/UV process led to the quantitative conversion of PHMB and thiol-PHMB complexes to Hg(II), with a yield between 91% and 98%, without using chemical oxidizing reagents and avoiding the use of toxic carcinogenic compounds. This reaction was followed by the reduction of Hg(II) to Hg(0) performed in a knitted reaction coil with NaBH(4) solution, and AFS detection in an Ar/H(2) miniaturized flame. The low MW power applied (18 W) allowed us to keep constant the temperature of the photochemical reactor (21 +/- 1 degrees C), using a flowing water bath. This avoided peak widening due to diffusion processes generally occurring at high temperatures and in the additional cooling coil. This method has been applied to the determination of thiols in human plasma, blood, and wine.
Journal/Review: ANALYTICAL CHEMISTRY
Volume: 83 Pages from: 338 to: 343
KeyWords: MicrowaveDOI: 10.1021/ac102462xCitations: 28data from “WEB OF SCIENCE” (of Thomson Reuters) are update at: 2020-11-29References taken from IsiWeb of Knowledge: (subscribers only)Connecting to view paper tab on IsiWeb: Click hereConnecting to view citations from IsiWeb: Click here