A Highly Sensitive and Selective Catalytic Determination of Mercury in Environmental Samples

作者：Mohamed Ashraf A^*; Ahmed Nagat A; El Shahat Mohamed F

来源：Bulletin of Environmental Contamination and Toxicology, 2016, 97(2): 232-236.

DOI：10.1007/s00128-016-1821-8

• Catalyzed ligand exchange
• Thiourea activator
• Mercury determination
• Vaccines
• Bass fish fillet
• Wastewaters

A simple, selective and highly sensitive spectrophotometric method has been developed for mercury determination utilizing its catalytic effect on the isoniazid-hexacyanoferrate (II) reaction. The paper presents for the first time (1) the catalytic effect of Hg (I) on the cited ligand substitution reactions and (2) the activating effect of thiourea on the behavior of mercury. The reaction was monitored spectrophotometrically at 423 nm using the initial rate method. The optimized reaction conditions were 5.0 mmol L-1 hexacyanoferrate (II), 0.5 mmol L-1 isoniazid, 150 mmol L-1 citrate buffer (pH 3.30 +/- A 0.05), and 0.2 mmol L-1 thiourea, at 50A degrees C. Linear calibration graphs were obtained for 1-100 and 1-55 A mu g L-1 with detection limits, based on the 3S(b)-criterion, of 1.2 and 1.8 A mu g L-1 of Hg (II) and Hg (I), respectively. The method was conveniently applied to samples of wastewaters, inactivated vaccines, and frozen Bass fish fillet, without any prior separation or preconcentration.

• 出版日期2016-8