title: Electrochemical detection of glutathione based on Hg(2+)-mediated strand displacement reaction strategy.
abstract: Glutathione (GSH) plays an important role in numerous cellular functions, and the abnormal GSH expression is closely related with many dangerous human diseases. In this work, we have proposed a simple but sensitive electrochemical method for quantitative detection of GSH based on an Hg(2+)-mediated strand displacement reaction. Owing to the specific binding of Hg(2+) with T-T mismatches, helper DNA can bind to 3' terminal of probe DNA 1 and initiate the displacement of probe DNA 2 immobilized on an electrode surface. However, Hg(2+)-mediated strand displacement reaction can be inhibited by the chelation of GSH with Hg(2+), thereby leading to an obvious electrochemical response obtained from methylene blue that is modified onto the probe DNA. Our method can sensitively detect GSH in a wide linear range from 0.5nM to 5μM with a low detection limit of 0.14nM, which can also easily distinguish target molecules in complex serum samples and even cell extractions. Therefore, this method may have great potential to monitor GSH in the physiological and pathological condition in the future.
authors.affiliation: Laboratory of Biosensing Technology, School of Life Sciences, Shanghai University, Shanghai 200444, PR China.
authors.forename: Yun
authors.initials: Y
authors.lastname: Lv
authors.affiliation: Laboratory of Biosensing Technology, School of Life Sciences, Shanghai University, Shanghai 200444, PR China.
authors.forename: Lili
authors.initials: L
authors.lastname: Yang
authors.affiliation: Laboratory of Biosensing Technology, School of Life Sciences, Shanghai University, Shanghai 200444, PR China.
authors.forename: Xiaoxia
authors.initials: X
authors.lastname: Mao
authors.affiliation: Laboratory of Biosensing Technology, School of Life Sciences, Shanghai University, Shanghai 200444, PR China.
authors.forename: Mengjia
authors.initials: M
authors.lastname: Lu
authors.affiliation: Laboratory of Biosensing Technology, School of Life Sciences, Shanghai University, Shanghai 200444, PR China. Electronic address: jingzhao@shu.edu.cn.
authors.forename: Jing
authors.initials: J
authors.lastname: Zhao
authors.affiliation: Department of Oncology, The First Affiliated Hospital of Nanjing Medical University, Nanjing 210029, PR China. Electronic address: ym.yin@hotmail.com.
authors.forename: Yongmei
authors.initials: Y
authors.lastname: Yin
mesh_terms: D015374:Biosensing Techniques / Q000379:methods*; D002413:Cations, Divalent / Q000737:chemistry; D004247:DNA / Q000737:chemistry*; D015342:DNA Probes / Q000737:chemistry; D055664:Electrochemical Techniques / Q000379:methods*; D004566:Electrodes; D005978:Glutathione / Q000032:analysis* / Q000097:blood; D006367:HeLa Cells; D006801:Humans; D057230:Limit of Detection; D008628:Mercury / Q000737:chemistry*; D008751:Methylene Blue / Q000737:chemistry; D009690:Nucleic Acid Conformation; D013936:Thymidine / Q000737:chemistry
chemical_list: D002413:Cations, Divalent; D015342:DNA Probes; D004247:DNA; D008628:Mercury; D005978:Glutathione; D008751:Methylene Blue; D013936:Thymidine
keywords: Electrochemical detection; Glutathione; Hg(2+); Strand displacement reaction