Thiol–Disulfide Exchange Reaction for Cellular Glutathione Detection with Surface-Enhanced Raman Scattering

Abstract

Abnormal glutathione (GSH) levels are related to several diseases, including cancer. In this paper, surface-enhanced Raman spectroscopy (SERS) based on a 2-(pyridyldithio)ethylamine (PDEA)-modified AgNPs@Si wafer is proposed for intracellular GSH detection. PDEA plays multifunctional roles in the method, including the participation in the thiol-disulfide exchange reaction and the contribution of a great SERS signal reporter. With the addition of GSH, the disulfide bond of PDEA will be broken, releasing the pyridine ring in PDEA and resulting in a signal-off SERS response. The developed specific reaction-based SERS assay can detect GSH levels as low as 2.5 × 10 M. Subsequently, we employed this method to evaluate cellular GSH levels and found that the levels in cancer cells are higher than those in normal cells. The PDEA-modified AgNPs@Si-based SERS protocol demonstrates good selectivity and high sensitivity, as well as robustness, which is suitable to evaluate cellular GSH levels.

Light-Responsive Metal–Organic Framework as an Oxidase Mimic for Cellular Glutathione Detection

“…To further validate the proposed assay for GSH, a commercial GSH kit was employed to evaluate the cellular GSH levels (Figures S13A,B). As shown in Figure D, the results of our method matched well with the GSH assay kit, both of which were in consistent with previously reported data . These results demonstrated that the PSMOF nanozyme acted as a reliable functional probe for cellular GSH evaluation.…”

“…As shown in Figure 5D, the results of our method matched well with the GSH assay kit, both of which were in consistent with previously reported data. 61 These results demonstrated that the PSMOF nanozyme acted as a reliable functional probe for cellular GSH evaluation.…”

Emerging trends in clinical implications of bio-conjugated silver nanoparticles in drug delivery

“…Subsequently, the thiol tagged AgNPs act as nucleophiles centered at 'S' atom and anchor directly to the maleimide ring bearing target nano-biomolecular system at its electron-deficient C3/ C4 positions through a thioether bond. The coupling reaction between the thiol group and maleimide occurs rapidly at room temperature and in aqueous solution [97] but with a low selectivity owing to the side reactions, such as intermolecular rearrangement leading to the formation of disulfides [98]. The efficiency of this reaction enhances with activating agents such as N-succinimidyl-Sacetylthioacetate (SATA) [99] or N-succinimidyl-3-(2-pyridyldithio) propionate (SPDP) [100,101].…”

Ce doped polyaniline nanoparticles for absorption and photoacoustic imaging response to GSH in vitro and in vivo

“…Therefore, it is very important to monitor GSH in organisms or in cells. To date, various approaches are utilized to detect GSH, including mass spectrometry, liquid chromatography, capillary electrophoresis, absorption/emission spectroscopy, and surface enhanced Raman scattering [ [12] , [13] , [14] , [15] ]. However, these methods can not be applied to monitor GSH in deep tissues in vitro and in vivo [ 16 ].…”