Graphene Quantum Dots Anchored Gold Nanorods for Electrochemical Detection of Glutathione

Abstract

In this manuscript, graphene quantum dots (GQDs) anchored gold nanorods (AuNRs) were prepared using a simple strategy. The formation of such hybrid materials was attained by mixing the GQDs (~2 -4 nm) and Cetyltrimethylammonium bromide (CTAB) capped AuNRs (length: 40 AE 3 and width: 20 AE 2 nm) under ultrasonication. The formation of GQDs anchored on the Au nanorod surface was confirmed using UV-Vis spectroscopy, X-ray diffraction (XRD), Raman spectroscopy, high-resolution transmission electron microscopy (HRTEM) and atomic force microscope (AFM). The possible complexation between acid groups of GQDs and CTAB capped AuNRs was utilized to reveal by FTIR spectroscopy. Such CTAB-AuNRs-GQDs possess catalytic surface with a high electrocatalytic activity, high sensitivity and selectivity for electrochemical determination of Glutathione (GSH) with a low detection limit of 0.23 mM and sensitivity of 1.49 mAmM À1 . Prominently, the CTAB-AuNRs-GQDs-based electrochemical biosensor has revealed great potential application for determination of GSH levels in real samples.[a] V. Figure 13. Amperometric responses of CTAB-AuNRs-GQDs/GC upon the successive addition of GSH and other interfering substances into PBS (0.1 M, pH 7) with stirring with an applied potential of GSH is 0.09 V.

Carbon Nanodots in Electrochemical Sensors and Biosensors: A Review

“…A list of applications of CNDs based electrochemical sensors for amino acids sensing and important DNA/RNA bases. Target Method Linear range Detection limit Refs. MIB/Au/ERGQD/GCE GSH DPV 0.03-1300.0 μM 9 nM [240] CTAB-AuNRs-GQDs/GCE GSH amperometry 0.5-7 μM 0.23 μM [241] GQDs/β-CD/GCE TRP isomers DPV -- [237] N-CDs/β-CD/GCE TRP isomers DPV [242] Fe FF/GQDs)/CS/CTAB TRP enantiomers DPV -- [244] GQDs-CS/GCE TRP enantiomers DPV -- [245] GQDs-TA/GCE TRP enantiomers DPV -- [246] NH β-CD-GQD/GCE L-Cys DPV 0.01-2 mM - [255] PPy/GQDs@PB/GF L-Cys amperometry 0.2-1000 μM 0.15 μM [236] rCDs-CS/PB/ITO L-Cys amperometry -- [256] Poly-L-cysteine/GQD/GNPs/GCE L-P DPV 0.5 nM-10 mM 0.1 nM [257] Poly(aspartic acid)-GQDs/GCE Taurine DPV -0.001 mM [258] AgNPs/GQD/GCE G A an electrochemical redox probe in order to bind to double stranded DNA (dsDNA) specifically. [284] In another example, an aptasensor is designed for hepatitis C virus (HCV) core antigen measurement.…”