ABSTRACT
One-step green synthetic approach,with bovine serum albumin(BSA) as stabilizer and reductant, was developed for preparation of BSA hybrid fluorescence gold nanoclusters (AuNCs@BSA). The prepared AuNCs@BSA exhibited strong red fluorescence under UV light illumination. Upon excited at 360 nm, the fluorescence spectrum of AuNCs@ BSA exhibited maximum emission peak at 635 nm. AuNCs@ BSA was presented as uniform spherical morphology with diameter at (2.0 ±0.05) nm. The fluorescence of AuNCs@BSA could be quenched by Hg2+because of its metallophilic reaction. Based on the fluorescent spectrometry, a rapid detection system was developed for Hg2+detection in tap water. The AuNCs@BSA amount, pH and buffer system were optimized in this study. According to optimization results, ultrapure water (pH 5.0) was selected to dilute the AuNCs@BSA by 100 times, and 50 μL/well of AuNCs@BSA dilution was applied to detect mercury ion in tap water. Under the optimized conditions, the detection could be completed within 3 min,the fluorescence intensity of the system was linearly proportional to the concentration of mercury ion in the range of 0.5–900 μg/L with linear equations y=-26.76lgx+803.1(0.5-75 μg/L,R2=0.9951) and y=-0.27x+762.02 (75-900 μg/L,R2=0.9959). The limit of detection was 0.14 μg/L(3σ). The average recoveries in spiked tape water samples ranged from 86.8%-113.4% with relative standard deviation of less than 15%. The result implied that the developed method was able to apply to detect mercury ion rapidly, sensitively and conveniently.