Sensitized spectrophotometric determination of trace Hg(II) in benzalkonium chloride media Original Research Article

A sensitized and convenient determination of trace Hg(II) with HgI42− complex in benzalkonium chloride media has been studied. The UV–VIS spectrum of HgI42− complex in benzalkonium chloride solution had higher sensitivity and reproducibility than that in aqueous solution. The HgI42− complex in benzalkonium chloride media was very stable at pH 10.0 and could be quantitatively complexed if I− was added to the sample solution more than 17 times the moles of Hg(II). The optimum concentration of benzalkonium chloride was 0.07%. The calibration curve of HgI42− complex with good linearity (R2=0.9963) was obtained in 0.07% benzalkonium chloride media. The detection limit was 1.8×10−8 M. Recovery yields of Hg(II) in spiked real and synthetic samples were mostly above 95%. Based on the experimental results, this proposed technique could be applied to the rapid and simple determination of trace Hg(II) in real samples.