title: Glutathione and L-cysteine modified silver nanoplates-based colorimetric assay for a simple, fast, sensitive and selective determination of nickel.
abstract: A novel colorimetric assay based on silver nanoplates (AgNPls) for detecting nickel ions (Ni(2+)) has been developed. Glutathione (GSH) and l-cysteine (Cys) were used to modify the AgNPls surface, exhibiting extremely high selectivity towards Ni(2+) over other metal ions under specific conditions. Upon addition of Ni(2+) 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 Ni(2+) 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 Ni(2+) 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 10-150 ppb (R(2)=0.9971) with the detection limit of 7.02 ppb or 120 nM (S/N=3). In addition, the developed sensor was applied to the determination of Ni(2+) 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 Ni(2+).
authors: Electrochemistry and Optical Spectroscopy Research Unit (EOSRU), Department of Chemistry, Faculty of Science, Chulalongkorn University, 254 Phayathai Road, Patumwan, Bangkok 10330, Thailand; Center of Excellence on Petrochemical and Materials Technology, Chulalongkorn University, Patumwan, Bangkok 10330, Thailand.
authors: Thanyaporn
authors: T
authors: Kiatkumjorn
authors: Electrochemistry and Optical Spectroscopy Research Unit (EOSRU), Department of Chemistry, Faculty of Science, Chulalongkorn University, 254 Phayathai Road, Patumwan, Bangkok 10330, Thailand.
authors: Poomrat
authors: P
authors: Rattanarat
authors: Department of Chemistry, Faculty of Science, Srinakharinwirot University, Sukhumvit 23, Wattana, Bangkok 10110, Thailand.
authors: Weena
authors: W
authors: Siangproh
authors: Electrochemistry and Optical Spectroscopy Research Unit (EOSRU), Department of Chemistry, Faculty of Science, Chulalongkorn University, 254 Phayathai Road, Patumwan, Bangkok 10330, Thailand; Center of Excellence on Petrochemical and Materials Technology, Chulalongkorn University, Patumwan, Bangkok 10330, Thailand.
authors: Orawon
authors: O
authors: Chailapakul
authors: Electrochemistry and Optical Spectroscopy Research Unit (EOSRU), Department of Chemistry, Faculty of Science, Chulalongkorn University, 254 Phayathai Road, Patumwan, Bangkok 10330, Thailand. Electronic address: narong.pr@chula.ac.th.
authors: Narong
authors: N
authors: Praphairaksit
mesh_terms: D003124:Colorimetry / Q000379:methods*; D003545:Cysteine / Q000737:chemistry*; D004784:Environmental Monitoring / Q000379:methods; D005978:Glutathione / Q000737:chemistry*; D006863:Hydrogen-Ion Concentration; D053768:Metal Nanoparticles / Q000737:chemistry* / Q000648:ultrastructure; D046529:Microscopy, Electron, Transmission; D009532:Nickel / Q000032:analysis* / Q000737:chemistry; D015203:Reproducibility of Results; D012834:Silver / Q000737:chemistry*; D017550:Spectroscopy, Fourier Transform Infrared
chemical_list: D012834:Silver; D009532:Nickel; D005978:Glutathione; D003545:Cysteine
keywords: Colorimetric assay; Glutathione; Nickel ion; Silver nanoplates; l-cysteine