title: A novel colorimetric assay for rapid detection of cysteine and Hg²⁺ based on gold clusters.
abstract: Inhibition and recovery of the catalytic activity of bovine serum albumin-capped gold nanoclusters (BSA-AuNCs) is observed for the first time by introduction of cysteine and Hg(2+). The prepared BSA-AuNCs possess highly intrinsic peroxidase-like activity. It can catalyze the oxidation of 3, 3, 5, 5-tetramethylbenzidine by H2O2 to produce a blue colored product. Based on this phenomenon, a new colorimetric assay for rapid, selective and sensitive detection of cysteine and Hg(2+) in aqueous solution has been demonstrated. The interaction process between target molecule and BSA-AuNCs is very fast, so that the whole test can be completed within ten minutes. Moreover, the fabricated colorimetric sensor is simple and cost-effective, without the need of nucleic acid based recognition element and complicated washing, separation and labeling process, thus holds great promise for routine analysis of cysteine and Hg(2+) in real samples.
authors.affiliation: College of Food Science, Fujian Agriculture and Forestry University, Fuzhou 350002, China.
authors.forename: Yi-Wei
authors.initials: YW
authors.lastname: Wang
authors.affiliation: Department of Pharmaceutical Analysis, Faculty of Pharmacy, Fujian Medical University, Fuzhou, Fujian 350004, China.
authors.forename: Shurong
authors.initials: S
authors.lastname: Tang
authors.affiliation: Key Lab of Analysis and Detection for Food Safety of MOE, Fujian Provincial Key Lab of Analysis and Detection Technology for Food Safety, Department of Chemistry, Fuzhou University, Fuzhou 350108, China. Electronic address: hhyang@fio.org.cn.
authors.forename: Huang-Hao
authors.initials: HH
authors.lastname: Yang
authors.affiliation: College of Food Science, Fujian Agriculture and Forestry University, Fuzhou 350002, China. Electronic address: sghgbode@163.com.
authors.forename: Hongbo
authors.initials: H
authors.lastname: Song
mesh_terms: D000818:Animals; D001560:Benzidines / Q000737:chemistry; D015374:Biosensing Techniques / Q000379:methods*; D002417:Cattle; D003124:Colorimetry / Q000379:methods*; D003545:Cysteine / Q000032:analysis* / Q000097:blood; D006046:Gold / Q000737:chemistry*; D006801:Humans; D006861:Hydrogen Peroxide / Q000737:chemistry; D057230:Limit of Detection; D008628:Mercury / Q000032:analysis*; D010084:Oxidation-Reduction; D014867:Water / Q000737:chemistry
chemical_list: D001560:Benzidines; D014867:Water; C029876:benzidine; D006046:Gold; D006861:Hydrogen Peroxide; D008628:Mercury; D003545:Cysteine
keywords: Colorimetric sensor; Cysteine; Gold clusters; Hg(2+); Rapid detection