【摘要】 基于半胱氨酸(Cys)中的-SH与Hg2+配合生成稳定的Hg(Cys)2,有效抑制抗坏血酸(Vc)还原Hg2+生成Hg0,进而抑制Hg0与金纳米棒(AuNRs)纵向部位的Au作用而生成金汞齐,导致AuNRs的纵向等离子体共振(Longitudinal surface plasmon resonance,LSPR)吸收峰红移,相应的吸光度(A)增大,并且伴随着溶液颜色的显著变化,同时随着Cys浓度的增大,吸光度A也逐渐增大,据此建立了一种快速、灵敏、简便的抑制Vc还原Hg2+非聚集AuNRs比色传感器测定Cys的新方法.在最佳实验条件下,比色传感器的线性范围为0.05～3.0μmol/L,量化限可达到0.030μmol/L,并成功应用于尿液中Cys的测定,结果与ICP-MS相吻合.此外,探讨了比色传感测定Cys的机理.更多还原

【Abstract】 The strong coordination of hydrosulfide groups(-SH) in cysteine(Cys) with Hg2+ results in a stable Hg(Cys)2 complex,which inhibits vitamine C(Vc) to reduce Hg2+ to form Hg0 and further inhibits the reaction between Hg0 and Au at the tips of gold nanorods(AuNRs) to form gold amalgamation(AuHg2(L)).As a result,the longitudinal surface plasmon resonance(LSPR) peak of AuNRs red shifts and the corresponding absorbance(A) increass along with a rapid color change from red to blue.Simultaneously,A gradually enlarges with the increase of Cys content.Bearing this in mind,a quick,sensitive and simple non-aggregation AuNRs colorimetric sensor for the determination of Cys has been established.Under optimized experimental conditions,the developed colorimetric sensor gave a linear range of 0.050~3.0 μmol/L with a limit of quantization(LOQ) of 0.030 μmol/L.The proposed colorimetric sensor has been successfully applied to the determination of Cys in human urine samples,the results agreed well with those obtained by inductively coupled plasma-mass spectroscopy(ICP-MS).Furthermore,the sensing mechanism for the determination of Cys is also discussed.更多还原