Graphene Quantum Dots Embedded Multiwall Carbon Nanotube for the Electrochemical Detection of Dopamine in Human Serum Sample

Abstract

A highly sensitive and selective electrochemical sensor was developed by the graphene quantum dots embedded multiwall carbon nanotube (GQDS@MWCNT) for the detection of dopamine in the human serum sample. Glucose based graphene quantum dots were synthesized and embedded with the multiwall carbon nanotube by the physiochemical interaction. Synthesized GQDS@MWCNT were characterized with UV-vis spectroscopy, Raman spectroscopy and High-resolution transmission. Graphene quantum dots were 1-3 nm in size and spherical in shape. Graphene quantum dots were well embedded with multiwall carbon nanotube. Electroanalytical sensitivity and selectivity were determined with cyclic voltammetry and differential pulse voltammetry. The electrochemical performance of synthesized materials was analyzed with different pH from 2 to 10 and also performed with ferry cyanide. The linear range of dopamine detection was found to be 0.25 µM to 250 µM and the detection limit is 18 nM. In addition, high reproducibility, stability and selectivity were obtained in the experiment. Moreover, the fabricated GQDS@MWCNT sensor was successfully applied in the determination of dopamine concentrations in human serum samples with satisfactory recoveries. The developed sensor is suitable for the medical and pharmaceutical field. Keywords: GQDS@MWCNT, Dopamine,Electrochemical Sensor, Human Serum Sample. Figure 1