title: Facile synthesis of N-acetyl-L-cysteine capped ZnS quantum dots as an eco-friendly fluorescence sensor for Hg2+.
abstract: This paper described an investigation of a novel eco-friendly fluorescence sensor for Hg(2+) ions based on N-acetyl-l-cysteine (NAC)-capped ZnS quantum dots (QDs) in aqueous solution. By using safe and low-cost materials, ZnS QDs modified by NAC were easily synthesized in aqueous medium via a one-step method. The quantitative detection of Hg(2+) ions was developed based on fluorescence quenching of ZnS QDs with high sensitivity and selectivity. Under optimal conditions, its response was linearly proportional to the concentration of Hg(2+) ions in a range from 0 to 2.4 × 10(-6) mol L(-1) with a detection limit of 5.0 × 10(-9) mol L(-1). Most of common physiologically relevant cations and anions did not interfere with the detection of Hg(2+). The proposed method was applied to the trace determination of Hg(2+) ions in water samples. The possible quenching mechanism was also examined by fluorescence and UV-vis absorption spectra.
authors.affiliation: Key Laboratory of Colloid and Interface Chemistry, Ministry of Education, Department of Chemistry, Shandong University, Jinan 250100, China.
authors.forename: Junling
authors.initials: J
authors.lastname: Duan
authors.forename: Xiaochen
authors.initials: X
authors.lastname: Jiang
authors.forename: Shouqing
authors.initials: S
authors.lastname: Ni
authors.forename: Min
authors.initials: M
authors.lastname: Yang
authors.forename: Jinhua
authors.initials: J
authors.lastname: Zhan
mesh_terms: D000042:Absorption; D000111:Acetylcysteine / Q000737:chemistry*; D002021:Buffers; D005456:Fluorescent Dyes / Q000138:chemical synthesis* / Q000737:chemistry; D055772:Green Chemistry Technology / Q000379:methods*; D006863:Hydrogen-Ion Concentration; D008628:Mercury / Q000032:analysis* / Q000737:chemistry; D045663:Quantum Dots; D013050:Spectrometry, Fluorescence / Q000379:methods*; D013056:Spectrophotometry, Ultraviolet; D013440:Sulfides / Q000737:chemistry*; D013997:Time Factors; D017967:Zinc Compounds / Q000737:chemistry*
chemical_list: D002021:Buffers; D005456:Fluorescent Dyes; D013440:Sulfides; D017967:Zinc Compounds; D008628:Mercury; C031238:zinc sulfide; D000111:Acetylcysteine