Selective recognition of Glutamate based on fluorescence enhancement of graphene quantum dot

Graphene quantum dots (GQDs) have successfully been utilized as an efficient nano-sized fluorescence chemosensor to detect selectively Glutamate (Glu) in Tris-HCl buffer solution (pH = 9). The fluorescence emission spectrum of graphene quantum dots was at about 430 nm. The study showed that fluorescence intensity of the quantum dot gradually enhanced with increase in concentration of Glutamate and any change in fluorescence intensity was directly proportional to the concentration of Glutamate. Under optimum conditions, the linear range for the detection of Glutamate was 1.6 x 10(-7) M to 1.0 x 10(-5) M with a detection limit of 5.2 x 10(-8) M. The sensor showed high selectivity toward Glutamate in comparison with other amino acids. (C) 2014 Elsevier B.V. All rights reserved.