Determination of thiomersal by flow injection coupled with microwave-assisted photochemical online oxidative decomposition of organic mercury and cold vapor atomic fluorescence spectroscopy

作者：Campanella Beatrice; Onor Massimo; Mascherpa Marco Carlo; D'Ulivo Alessandro; Ferrari Carlo; Bramanti Emilia^*

来源：Analytica Chimica Acta, 2013, 804: 66-69.

DOI：10.1016/j.aca.2013.10.018

• Thiomersal
• Atomic fluorescence spectrometry
• Flow injection analysis
• Organic mercury compounds
• Mercury oxidation

We developed a flow injection (FI) method for the determination of thiomersal (sodium ethylmercurithiosalicylate, C9H9HgNaO2S) based on the UV/microwave (MW) photochemical, online oxidation of organic mercury, followed by cold vapor generation atomic fluorescence spectrometry (CVG-AFS) detection. Thiomersal was quantitatively converted in the MW/UV process to Hg(II), with a yield of 97 +/- 3%. This reaction was followed by the reduction of Hg(II) to Hg(0) performed in a knotted reaction coil with NaBH4 solution, and AFS detection in an Ar/H-2 miniaturized flame. The method was linear in the 0.01-2 mu g mL(-1) range, with a LOD of 0.003 mu g mL(-1). This method has been applied to the determination of thiomersal in ophthalmic solutions, with recoveries ranging between 97% and 101%. We found a mercury concentration in commercial ophthalmic solutions ranging between 7.5 and 59.0 mu g mL(-1).

• 出版日期2013-12-4