Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2014 Feb 27;9(1):99.
doi: 10.1186/1556-276X-9-99.

DNA-templated synthesis of PtAu bimetallic nanoparticle/graphene nanocomposites and their application in glucose biosensor

Jing Leng, Wen-Min Wang, Li-Min Lu  1 , Ling Bai, Xin-Lan Qiu
Affiliations

DNA-templated synthesis of PtAu bimetallic nanoparticle/graphene nanocomposites and their application in glucose biosensor

Jing Leng et al. Nanoscale Res Lett. .

Abstract

In this paper, single-stranded DNA (ss-DNA) is demonstrated to functionalize graphene (GR) and to further guide the growth of PtAu bimetallic nanoparticles (PtAuNPs) on GR with high densities and dispersion. The obtained nanocomposites (PtAuNPs/ss-DNA/GR) were characterized by transmission electron microscopy (TEM), energy-dispersive X-ray spectrometer (EDS), and electrochemical techniques. Then, an enzyme nanoassembly was prepared by self-assembling glucose oxidase (GOD) on PtAuNP/ss-DNA/GR nanocomposites (GOD/PtAuNPs/ss-DNA/GR). The nanocomposites provided a suitable microenvironment for GOD to retain its biological activity. The direct and reversible electron transfer process between the active site of GOD and the modified electrode was realized without any extra electron mediator. Thus, the prepared GOD/PtAuNP/ss-DNA/GR electrode was proposed as a biosensor for the quantification of glucose. The effects of pH, applied potential, and temperature on the performance of the biosensor were discussed in detail and were optimized. Under optimal conditions, the biosensor showed a linearity with glucose concentration in the range of 1.0 to 1,800 μM with a detection limit of 0.3 μM (S/N = 3). The results demonstrate that the developed approach provides a promising strategy to improve the sensitivity and enzyme activity of electrochemical biosensors.

PubMed Disclaimer

Figures

Figure 1
Figure 1
The formation procedures of GOD/PtAuNP/ss-DNA/GR nanocomposites.
Figure 2
Figure 2
Photographic and TEM images and EDS spectra. (A) Photographic images of (a) unmodified GR and (b) ss-DNA/GR in water. TEM images of (B) ss-DNA/GR and (C) PtAuNP/ss-DNA/GR nanocomposites. (D) EDS spectra of PtAuNP/ss-DNA/GR nanocomposites.
Figure 3
Figure 3
Impedance spectrum of various electrodes in 5.0 mM K3Fe(CN)6/K4Fe(CN)6 (1:1) containing 0.1 M KCl. Bare electrode (curve a), ss-DNA/GR modified electrode (curve b), PtAuNP/ss-DNA/GR modified electrode (curve c), and GOD/PtAuNP/ss-DNA/GR modified electrode (curve d).
Figure 4
Figure 4
Cyclic voltammograms of GOD/PtAuNP/ss-DNA/GR modified electrode. They are in (curve a) N2-saturated and O2-saturated PBS (pH 7.0) in the (curve b) absence and (curve c) presence of 1.0 mM glucose at 100 mV s-1.
Figure 5
Figure 5
Effects of (A) pH, (B) applied potential, and (C) temperature. These are effects on amperometric response of the GOD/PtAuNP/ss-DNA/GR modified electrode to 0.1 mM glucose in 0.1 M PBS (pH 7.0).
Figure 6
Figure 6
Amperometric responses of modified electrodes to additions of 0.1 mM glucose in 10-mL PBS at -0.2 V. GOD/ss-DNA/GR (curve a), GOD/PtNP/ss-DNA/GR (curve b), GOD/AuNP/ss-DNA/GR (curve c), and GOD/PtAuNP/ss-DNA/GR (curve d) modified electrodes. Left inset is the calibration curve of the biosensor.
See this image and copyright information in PMC

References

    1. Zheng BZ, Xie S, Qian L, Yuan HY, Xiao D, Choi M. Gold nanoparticles-coated eggshell membrane with immobilized glucose oxidase for fabrication of glucose biosensor. Sens Actuators B. 2011;9:49–55. doi: 10.1016/j.snb.2010.09.051. - DOI
    1. Han AX, Wu GS, Liang Q, Zhang FS. Direct spectrophotometric determination of the blood glucose by the method of conjugation enzyme. Chin J Anal Chem. 2003;9:1417–1420.
    1. Liu XQ, Niu W, Li HJ, Han S, Hu LZ, Xu GB. Glucose biosensor based on gold nanoparticle-catalyzed luminol electrochemiluminescence on a three-dimensional sol–gel network. Electrochem Commun. 2008;9:1250–1253. doi: 10.1016/j.elecom.2008.06.009. - DOI
    1. Xu CX, Huang KJ, Chen XM, Xiong XQ. Direct electrochemistry of glucose oxidase immobilized on TiO2-graphene/nickel oxide nanocomposite film and its application. J Solid State Electrochem. 2012;9:3747–3752. doi: 10.1007/s10008-012-1813-5. - DOI
    1. Li J, Yang ZJ, Xu Q, Qu QS, Hu XY. Tin disulfide nanoflakes decorated with gold nanoparticles for direct electrochemistry of glucose oxidase and glucose biosensing. Microchim Acta. 2012;9:265–272. doi: 10.1007/s00604-012-0889-z. - DOI

LinkOut - more resources