title: Colorimetric detection of glutathione in cells based on peroxidase-like activity of gold nanoclusters: A promising powerful tool for identifying cancer cells.
abstract: Glutathione (GSH), the most abundant biothiol in cells, not only plays a pivotal role in protective and detoxifying functions of the cell, but also serves as a very important mediator in many cellular functions. Especially, the difference of GSH level between cancer cells and normal cells is regarded as one of most important physiological parameters for cancer diagnosis. It is thereby extremely necessary to develop a simple, sensitive, and reliable analytical method for detection of GSH in cells. On the basis of the inhibition effect of GSH on the peroxidase-like activity of GSH stabilized gold nanoclusters, here a novel and facile strategy for colorimetric detection of cellular GSH level was well established. In this sensing system, GSH can effectively inhibit the oxidation of peroxidase substrate 3,3',5,5'-tetramethylbenzidine (TMB) to produce a blue colored product. Under the optimized conditions, the absorbance at 652 nm against GSH concentration shows a linear relationship within a range from 2 to 25 μM with detection limit of 420 nM. This excellent property allows our approach to be used to accurately evaluate the cellular GSH levels, and it is revealed that the overall GSH level in cancer cells was much higher than that in normal cells. The presented assay will enable a powerful tool for identifying cancer cells in a simple manner for biomedical diagnosis associated with GSH.
authors.affiliation: College of Chemistry, Nanchang University, Nanchang 330031, China.
authors.forename: Jiayu
authors.initials: J
authors.lastname: Feng
authors.affiliation: College of Chemistry, Nanchang University, Nanchang 330031, China.
authors.forename: Pengcheng
authors.initials: P
authors.lastname: Huang
authors.affiliation: Institute of Translational Medicine, Nanchang University, Nanchang 330031, China.
authors.forename: Shuizhen
authors.initials: S
authors.lastname: Shi
authors.affiliation: Institute of Translational Medicine, Nanchang University, Nanchang 330031, China.
authors.forename: Ke-Yu
authors.initials: KY
authors.lastname: Deng
authors.affiliation: College of Chemistry, Nanchang University, Nanchang 330031, China. Electronic address: fywu@ncu.edu.cn.
authors.forename: Fang-Ying
authors.initials: FY
authors.lastname: Wu
mesh_terms: D045744:Cell Line, Tumor; D003124:Colorimetry; D005978:Glutathione / Q000032:analysis*; D006046:Gold; D006801:Humans; D057230:Limit of Detection; D053768:Metal Nanoparticles / Q000737:chemistry*; D009369:Neoplasms / Q000175:diagnosis; D010084:Oxidation-Reduction; D009195:Peroxidase; D000074084:THP-1 Cells
chemical_list: D006046:Gold; D009195:Peroxidase; D005978:Glutathione
keywords: Cancer cells; Glutathione; Gold nanocluster; Peroxidase-like activity