Facile Designing of a Colorimetric Plasmonic Gold Nanosensor for Selective Detection of Cysteine over Other Biothiols

摘要

Herein, we present a facile synthesis of well dispersed gold nanoparticles (AuNPs) using 1,3-diamino-2-hydroxypropane- N,N,N’,N’-tetraacetic acid (TA) as reducing as well as stabilizing agent. The bright red colored gold nanoparticles were found to be quite stable within the broad pH range of 4 to 10. The same detected Cysteine (Cys) selectively over other common interfering biothiols like homocysteine (Hcy), glutathione (GSH) and methionine (Met). The bright red colored AuNPs displayed bluish gray color upon their interaction with Cys within20 seconds only. The ability towards assay of Cys in pharmaceutical sample made this probe further lucrative. The possibility of onspot assessement by this probe was also tested through cotton swab experiment.