Glutathione and l-cysteine modified silver nanoplates-based colorimetric assay for a simple, fast, sensitive and selective determination of nickel
2014
Kiatkumjorn, Thanyaporn | Rattanarat, Poomrat | Siangproh, Weena | Chailapakul, Orawon | Praphairaksit, Narong
A novel colorimetric assay based on silver nanoplates (AgNPls) for detecting nickel ions (Ni²⁺) has been developed. Glutathione (GSH) and l-cysteine (Cys) were used to modify the AgNPls surface, exhibiting extremely high selectivity towards Ni²⁺ over other metal ions under specific conditions. Upon addition of Ni²⁺ to the modified AgNPls solution, a distinctive color change can be clearly observed by naked eyes as a result of the aggregation of AgNPls induced by the binding between Ni²⁺ and the modified ligands. To verify a complete self-assembly of the GSH and Cys onto AgNPls surface, the modified AgNPls were characterized using Fourier transform infrared spectroscopy (FTIR), ultraviolet–visible spectroscopy (UV–vis) and transmission electron microscopy (TEM), respectively. Moreover, various parameters affecting the Ni²⁺ quantification including the modifier ratio, pH, reaction time, and interferences were investigated. With UV–vis spectrophotometric measurement under optimal conditions, a quantitative linearity was established in the range of 10–150ppb (R²=0.9971) with the detection limit of 7.02ppb or 120nM (S/N=3). In addition, the developed sensor was applied to the determination of Ni²⁺ in waste samples from a jewelry factory and a car manufacturer with satisfactory results. Overall, this alternative approach presents a simple, rapid, sensitive and selective detection of Ni²⁺.
显示更多 [+] 显示较少 [-]