Mercury colorimetric detection

Boopathi, S., Senthilkumar, S., et al. Facile and One Pot Synthesis of Gold Nanoparticles Using Tetraphenylborate and Polyvinylpyrrolidone for Selective Colorimetric Detection of Mercury Ions in Aqueous Medium. Journal of Analytical Methods in Chemis-try,2012(2012). 

Figure 3.5 Schematic representation of the colorimetric mercury detection method for Hg2+ that relies on thymidine-Hg2+-thymidine coordination chemistry and...

Earlier methods used to determine mercury in biological tissue and fluids were mainly colorimetric, using dithizone as the com-plexing agent. However, during the past two to three decades, AAS methods - predominantly the cold vapor principle with atomic absorption or atomic fluorescence detection - have become widely used due to their simplicity, sensitivity, and relatively low price. Neutron activation analysis (NAA), either in the instrumental or radiochemical mode, is still frequently used where nuclear reactors are available. Inductively coupled plasma mass spectrometry (ICP-MS) has become a valuable tool in mercury speciation. Gas and liquid chromatography, coupled with various detectors have also gained much importance for separa-tion/detection of mercury compounds (Table 17.1). 

The upstream electrode acts as a very-low>volume postcolumn reactor. The simplicity of this sdieme is easily appreciated by the fact that previous schemes to detect thiols and disulfides required wet chemical steps to sepa> rate the groups, chemical reduction of the disulfide, and subsequent de > tion of all as thiol using colorimetric coupling reagents. Here the reactor is simply turned on or off by an electronic switch. Preliminary identification of an unknown peak as disulfide may thus rdy on the disappearance of the peak when the reactor is off (Fig. 64). The use of twin mercury-film electrodes is essential to the success of this aiqilication and imparts hi selectivity to the analysis. 

You J, Hu HZ, Zhou JP, Zhang LN, Zhang YP, Kondo T (2013) Novel cellulose polyampholyte-gold nanoparticle-based colorimetric competition assay for the detection of cysteine and mercury(II). Langmuir 29 5085-5092... 

Fluorescent and colorimetric sensors for detection of lead, cadmium, and mercury ions 12CSR3210. 

Huang CC, Chang HT (2006) Selective gold-nanoparticle-based tum-on fluorescent sensors for detection of mercury(II) in aqueous solution. Anal Chem 78 8332-8338 He X, Liu H, Li Y et al (2005) Gold nanoparticle-based fluorometric and colorimetric sensing of copper(II) ions. Adv Mater 17 2811-2815... 

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