Cysteine, homocysteine and glutathione guided hierarchical self-assemblies of spherical silver nanoparticles paving the way for their naked eye discrimination in human serum

Abstract

Herein, we unravel the naked eye discrimination of three important biothiols viz., cysteine, homocysteine and glutathione through silver nanoparticles immobilized over an azonaphthol. This visual detection is an outcome of three hierarchical self-assemblies in the form of flowers, thorns and petals guided by cysteine, homocysteine and glutathione respectively. The bright yellow silver nanoprobe displayed bluish gray colour with cysteine, purple pink colour with homocysteine and orange colour with glutathione with lowest detection limits of 260 nM, 10 nM and 4.11 μM respectively. The same nanoprobe was also successful in detecting the above mentioned biothiols in human serum.