Highly sensitive fluorogenic sensing of L-Cysteine in live cells using gelatin-stabilized gold nanoparticles decorated graphene nanosheets

• Published in: Sensors and actuators. B, Chemical Chemical, 2018-04, Vol.259, p.339-346
• Main Authors: Thirumalraj, Balamurugan, Dhenadhayalan, Namasivayam, Chen, Shen-Ming, Liu, Yan-Jin, Chen, Tse-Wei, Liang, Po-Huang, Lin, King-Chuen
• Format: Article
• Language: English
• Subjects: Biocompatibility; Bioimaging; Cysteine; Detection; Energy transfer; Fluorescence; Gelatin; Gold; Gold nanoparticles; Graphene; Homeostasis; L-Cysteine; Medical imaging; Nanoparticles; Nanosheets; Physiochemistry; Reduced graphene oxide; Restoration
• ISSN: 0925-4005; 1873-3077; 0925-4005
• DOI: 10.1016/j.snb.2017.12.028

[Display omitted] •A fluorogenic detection of L-Cysteine was investigated using rGO/Au nanohybrids.•The rGO/Au nanohybrids was prepared by one-pot hydrothermal method.•A lower LOD (0.51 nm) was achieved.•Practicality of the sensor was evaluated in live cancer cells. A highly sensitive and selective fluorogenic sensing of L-Cysteine (L-Cys) was implemented based on gelatin stabilized gold nanoparticles decorated reduced graphene oxide (rGO/Au) nanohybrid. The rGO/Au nanohybrid was prepared by the one-pot hydrothermal method and well characterized by different physiochemical techniques. The nanohybrid exhibits a weak fluorescence of rGO due to the energy transfer from the rGO to Au NPs. The rGO/Au nanohybrid shows enhanced fluorescence activity due to the restoration of quenched fluorescence of rGO/Au nanohybrid in presence of L-Cys. The rGO/Au nanohybrid exhibits much lower detection limit of 0.51 nM for L-Cys with higher selectivity. The fluorescence sensing mechanism arose from the fluorescence recovery due to the stronger interaction between Au NPs and L-Cys, and consequently, the energy transfer was prevented between rGO and Au NPs. The practicability of rGO/Au sensor was implemented by invitro bioimaging measurements in Colo-205 (colorectal adenocarcinoma) and MKN-45 (gastric carcinoma) cancer live cells with excellent biocompatibility.