Fluorescent Indicator Displacement Assay: Ultrasensitive Detection of Glutathione and Selective Cancer Cell Imaging.
This Research Article reports the development of nanohybrid comprising of anionic carbon dots (ACD) protected gold nanoparticle (GNP). ACD directly cap GNP through its anionic surface functionalization leading to the formation of stable aqueous GNP dispersion. This newly developed ACD-GNP nanohybrid has been thoroughly characterized by different spectroscopic and microscopic techniques. This nanohybrid is successfully employed toward the selective sensing of glutathione (GSH). The mechanism of GSH sensing by this nanosensor is based on the GSH triggered displacement of fluorescent indicator ACD from the GNP surface. Upon capping GNP, intrinsic fluorescence of ACD gets quenched. Addition of GSH displaces the fluorescent indicator ACD from GNP surface and restores the fluorescence signal of ACD. This nanosensor exhibits very high selectivity as well as sensitivity toward glutathione over the other biothiols and can detect as low as 6 nM of GSH. More importantly, selective imaging of the cancer cells over the noncancerous cells was achieved by this ACD-GNP hybrid implying its potential applications in biosensing, as well as in cancer diagnosis.
Department of Biological Chemistry, Indian Association for the Cultivation of Science Jadavpur , Kolkata-700 032, India.
Krishnendu
K
Das
Department of Biological Chemistry, Indian Association for the Cultivation of Science Jadavpur , Kolkata-700 032, India.
Saheli
S
Sarkar
Department of Biological Chemistry, Indian Association for the Cultivation of Science Jadavpur , Kolkata-700 032, India.
Prasanta Kumar
PK
Das
D015374:Biosensing Techniques; D002244:Carbon; D005456:Fluorescent Dyes; D005978:Glutathione / Q000737:chemistry*; D006046:Gold; D053768:Metal Nanoparticles
D005456:Fluorescent Dyes; D002244:Carbon; D006046:Gold; D005978:Glutathione
carbon dots; glutathione; gold nanoparticle; imaging; nanohybrid; sensing