Detection Methods Of Mercury And Metallothioneins Based On Gold Nanoparticle-mercury Complex

Mercury is a heavy metal which can cause severe adverse effects on human health, and has been classified as a class of priority-control pollutions by several countries. The existing methods for the determination of mercury mostly require tedious and painstaking procedures, and expensive and complicated instruments. Therefore, it is significant to develop a method for sensitive, simple and selective detection of mercury in pollution monitoring, and safety evaluation and so on.In the chapter2, a catalytic colorimetric method to detect Hg2+has been developed based on gold nanoparticle and3,3’,5,5’-tetramethylbenzidine (TMB). In the Tris-acetate buffer solution of pH7.0, AuNPs can interact with Hg2+to form AuNPs-Hg peroxidase mimetic, leading to catalyze color reaction of3,3’,5,5’-tetramethylbenzidine.△A was directly proportional to the concentration of Hg2+in the range of9.14×10-8mol·L-1～7.69×10-6mol·L-1. The equation of linear regression was△A=0.001+0.091c(×10mol·L-1) with a correlation coefficient (r) of0.996. The limit of detection (LOD) was2.74×10-8mol·L-1. The proposed method was simple, rapid and selective.In the chapter3, a novel catalytic colorimetric method to detect metallothioneins has been developed based on gold nanoparticle,3,3’,5,5’-tetramethylbenzidine and Hg. In the Tris-acetate buffer solution of pH7.0, metallothioneins can compete with AuNPs for reacting with Hg2+, resulting in inhibiting the formation of AuNPs-Hg peroxidase mimetic, and then leading to decrease of catalytic color reaction of TMB.△A was directly proportional to the concentration of MTs in the range of5.93×10-9～9.23×10-8mol·L-1. The equation of linear regression was△A=0.042+0.066c (×10-8mol·L-1) with a correlation coefficient (r) of0.990. The limit of detection (LOD) was1.78×10-9mol·L-1. The proposed method was simple, rapid, sensitive and selective.In the chapter4, a novel ultraviolet spectrophotometry method to detect Hg2+has been developed based on gold nanoparticle and metallothioneins. Hg2+can induce AuNPs-MTs complex to aggregate in the Tris-acetate buffer solution of pH7.0, resulting in the change of ultraviolet absorbance.△(A626/A524) was directly proportional to the concentration of Hg2+in the range of5.6×10-8mol·L-1～2.0×10-6mol·L-1. The equation of linear regression was△(A626/A524)=-0.0132+0.4072c (×10-6mol·L-1) with a correlation coefficient (r) of0.9961. The limit of detection (LOD) was1.68×10-8mol·L-1. The proposed method was simple, rapid and sensitive.