Determination of trace mercury by solid substrate-room temperature phosphorimetry quenching method based on catalytic effect of Hg2+ on formation of the ion association complex [Sn(XO)6]4+.[(Fin)4].
A new method for the determination of trace mercury by solid substrate-room temperature phosphorimetry (SS-RTP) quenching method has been established. In glycine-HCl buffer solution, xylenol orange (XO) can react with Sn4+ to form the complex [Sn(XO)6]4+. [Sn(XO)6]4+ can interact with Fin- (fluorescein anion) to form the ion associate [Sn(XO)6]4+.[(Fin)4]-, which can emit strong and stable room temperature phosphorescence (RTP) on polyamide membrane (PAM). Hg2+ can catalyze H2O2 oxidizing the ion association complex [Sn(XO)6]4+.[(Fin)4]-, which causes the RTP to quench. The DeltaIp value is directly proportional to the concentration of Hg2+ in the range of 0.016-1.6 fg spot(-1) (corresponding concentration: 0.040-4.0 pg ml(-1), 0.40 microl spot(-1)), and the regression equation of working cure is DeltaIp=10.03+83.15 m Hg2+ (fg spot(-1)), (r=0.9987, n=6) and the detection limit (LD) is 3.6 ag spot(-1)(corresponding concentration: 9.0 x 10(-15) g ml(-1), the sample volume: 0.4 microl). This simple, rapid, accurate method is of high selectivity and good repeatability, and it has been successfully applied to the determination of trace mercury in real samples. The reaction mechanism for catalyzing H2O2 oxidizing the ion association complex ([Sn(XO)6]4+.[(Fin)4]-) SS-RTP quenching method to determine trace mercury is also discussed.
Liu
Jia-Ming
JM
Department of Chemistry, Zhangzhou Normal College, Zhangzhou 363000, PR China. zzsyliujiaming@163.com
Wu
Ruo-Hong
RH
Li
De-Chang
DC
Zhou
Ping
P
Zheng
Min-Min
MM
Zeng
Xiao-Yi
XY
Liu
Dong-Xia
DX
Huang
Xiao-Mei
XM
Zhu
Guo-Hui
GH
D005452:Fluoresceins; D007202:Indicators and Reagents; D008163:Luminescent Measurements / Q000379:methods*; D008628:Mercury / Q000032:analysis*; D013053:Spectrophotometry / Q000379:methods
D005452:Fluoresceins; D007202:Indicators and Reagents; D008628:Mercury