Abstract：
In this study, a screen-printed carbon electrode (SPCE) based on in situ deposition modification was developed for the sensitive, rapid, easy and convenient determination of As(III) in water and tea by linear sweep anodic stripping voltammetry (LSASV). The screen-printed carbon electrodes were placed in a solution consisting of As(III) solution, chlorauric acid and L-cysteine. Under certain electrical potential, the chloroauric acid was reduced to gold nanoparticles (AuNPs) on the SPCE. L-cysteine was self-assembled onto AuNPs and promoted the enrichment of As(III), thus enhancing the determination specificity and sensitivity of As(III). The method achieved a limit of determination (LOD) of 0.91 ppb (µg L-1), a linear range of 1~200 µg L-1, an inter-assay coefficient of variation of 5.3% and good specificity. The developed method was successfully applied to the determination of As(III) in tap water and tea samples, with a recovery rate of 93.8%~105.4%, and further validated by inductively coupled plasma mass spectrometry (ICP-MS). The developed method is rapid, convenient and accurate, holding great promise in the on-site determination of As(III) in tap water and tea leaves, and it can be extended to the detection of other samples.
摘要：
在这项研究中,开发了一种基于原位沉积改性的丝网印刷碳电极(SPCE)，快速,线性扫描阳极溶出伏安法(LSASV)测定水和茶叶中的As(III)。将丝网印刷的碳电极置于由As(III)溶液组成的溶液中，氯金酸和L-半胱氨酸。在一定的电势下,在SPCE上，氯金酸被还原成金纳米颗粒（AuNPs）。L-半胱氨酸自组装到AuNPs上并促进As(III)的富集,从而提高了As(III)的测定特异性和灵敏度。该方法的测定限（LOD）为0.91ppb（µgL-1），线性范围为1~200µgL-1，测定间变异系数为5.3%，特异性好。该方法已成功应用于自来水和茶叶样品中As(Ⅲ)的测定,回收率为93.8%~105.4%,并通过电感耦合等离子体质谱(ICP-MS)进一步验证。所开发的方法是快速的，方便准确,在现场测定自来水和茶叶中的As（III）方面有很大的希望，它可以扩展到其他样品的检测。
