Highly Sensitive Detection of Trace Hg2+ Based on Fine CdS Nanodots Grew from a DNA-Directed Alternate Dialysis Method
Fine CdS nanodots (~5 nm) have been prepared in aqueous solution under the control of ds-DNA via a novel alternating dialysis procedure, which have been characterized by TEM, UV-vis, fluorescence (FL) and resonance light scattering (RLS) spectra. The resultant well-dispersed CdS nanodots present a strong FL peak at 339 nm and RLS bands around 394 nm. Interestingly, it was found that the quenching of FL and the enhancing of RLS intensity are dependent on the concentration of Hg2+, both of which showed good linear relationship over the range of 0.01-100 mmol/L, with a detection limit (3s) as low as 0.91 nmol/L. Good selectivity of this method for Hg2+ analysis has also been checked over other metal ions.
Zhong Cao, Xueqiang Cao, Lixian Sun, Yinghe He
S. Chen et al., "Highly Sensitive Detection of Trace Hg2+ Based on Fine CdS Nanodots Grew from a DNA-Directed Alternate Dialysis Method", Advanced Materials Research, Vols. 239-242, pp. 536-539, 2011