Voltammetric determination of mercury (II) in aqueous media using glassy carbon electrodes modified with novel calix[4]arene.
A novel calix[4]arene derivative containing benzothiazole group was coated on glassy carbon electrode (GCE) and then applied to the recognition of mercury ion. Cyclic and square wave voltammetric results showed that the modified electrode selectively recognizes Hg(2+) ion in aqueous media. A new anodic stripping peak at -0.3 V (vs. Ag/Ag(+)) can be obtained by scanning the potential from -0.6 to 0.6 V, and the peak currents are proportional to the Hg(2+) concentration. The modified electrode in a 0.1 M H(2)SO(4)+0.01 M NaCl solution shows linear voltammetric response in the range of 25-300 mug l(-1) and detection limit of 5 mug l(-1) (ca. 2.5x10(-8) M). This modified GCE does not present any significant interference from alkali, alkaline and transition metal ions except for Pb(2+), Ag(+) and Cu(2+) ions. Only 500, 50 and 100-fold molar excess of Pb(2+), Ag(+) and Cu(2+) ions, respectively, can lead to voltammetric response comparable with that of Hg(2+). The proposed method was successfully applied to determine mercury in natural water.
Lu
Jianquan
J
Department of Chemistry, Nankai University, Tianjin 300071, People's Republic of China; Department of Chemistry, Hubei Normal University, Huangshi 435002, People's Republic of China.
He
Xiwen
X
Zeng
Xianshun
X
Wan
Qijin
Q
Zhang
Zhengzhi
Z