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Spontaneous Deposition of Prussian Blue on Multi-Walled Carbon Nanotubes and the Application in an Amperometric Biosensor

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ABSTRACT

A simple method has been developed for the spontaneous deposition of Prussian blue (PB) particles from a solution containing only ferricyanide ions onto conducting substrates such as indium tin oxide glass, glassy carbon disk and carbon nanotube (CNT) materials. Formation of PB deposits was confirmed by ultraviolet-visible absorption spectrometry and electrochemical techniques. The surface morphology of the PB particles deposited on the substrates was examined by atomic force microscopy and scanning electron microscopy. CNT/PB composite modified glassy carbon electrodes exhibited an electrocatalytic property for hydrogen peroxide reduction. These modified electrodes exhibited a high sensitivity for electrocatalytic reduction of hydrogen peroxide at −0.05 V (vs. Ag/AgCl), probably due to the synergistic effect of CNT with PB. Then, CNT/PB modified electrodes were further developed as amperometric glucose biosensors. These biosensors offered a linear response to glucose concentration from 0.1 to 0.9 mM with good selectivity, high sensitivity of 0.102 A M−1 cm−2 and short response time (within 2 s) at a negative operation potential of −0.05 V (vs. Ag/AgCl). The detection limit was estimated to be 0.01 mM at a signal-to-noise ratio of 3.

No MeSH data available.


(a) Amperometric determination of H2O2 for GC electrodes modified with different materials: CNT-PB, PB, and CNT at −0.05 V (vs. Ag/AgCl) with successive addition of 10 μM H2O2 in phosphate buffer (pH 7.4). (b) Calibration plots for H2O2 determination at different modified GC electrodes.
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nanomaterials-02-00428-f005: (a) Amperometric determination of H2O2 for GC electrodes modified with different materials: CNT-PB, PB, and CNT at −0.05 V (vs. Ag/AgCl) with successive addition of 10 μM H2O2 in phosphate buffer (pH 7.4). (b) Calibration plots for H2O2 determination at different modified GC electrodes.

Mentions: H2O2 is a by-product of enzymatic reactions involving different oxidase enzymes. For an oxidase-based biosensor, detection of H2O2 at low potential is advantageous for both high sensitivity and high selectivity in the detection of analytes. PB offers effective electron transfer for H2O2 detection. The reduction of H2O2 at different modified electrodes (GC/CNT/PB, GC/PB, and GC/CNT) was examined. Figure 5a shows the amperometric response curves for the reduction of H2O2 examined at −0.05 V by successive addition of 10 μM H2O2 into the phosphate buffer (pH 7.4). Usually, the amperometric current response exhibited a stepwise increase upon addition of H2O2 and reached equilibrium within 2 s, for the electrodes examined in this study. The electrode modified with CNT alone did not favor the reduction of H2O2 at −0.05 V. In contrast, the electrode modified with PB only showed activity of H2O2 reduction. Interestingly, a much enhanced current response was observed for the GC/CNT/PB modified electrode, demonstrating the synergistic effects of PB and CNT. The GC/CNT/PB electrode responded more sensitively to H2O2, and showed a three-fold increase in response current compared with that for the GC/PB electrode. The GC/CNT/PB electrode can be applied for a practical determination of H2O2.


Spontaneous Deposition of Prussian Blue on Multi-Walled Carbon Nanotubes and the Application in an Amperometric Biosensor
(a) Amperometric determination of H2O2 for GC electrodes modified with different materials: CNT-PB, PB, and CNT at −0.05 V (vs. Ag/AgCl) with successive addition of 10 μM H2O2 in phosphate buffer (pH 7.4). (b) Calibration plots for H2O2 determination at different modified GC electrodes.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC5304602&req=5

nanomaterials-02-00428-f005: (a) Amperometric determination of H2O2 for GC electrodes modified with different materials: CNT-PB, PB, and CNT at −0.05 V (vs. Ag/AgCl) with successive addition of 10 μM H2O2 in phosphate buffer (pH 7.4). (b) Calibration plots for H2O2 determination at different modified GC electrodes.
Mentions: H2O2 is a by-product of enzymatic reactions involving different oxidase enzymes. For an oxidase-based biosensor, detection of H2O2 at low potential is advantageous for both high sensitivity and high selectivity in the detection of analytes. PB offers effective electron transfer for H2O2 detection. The reduction of H2O2 at different modified electrodes (GC/CNT/PB, GC/PB, and GC/CNT) was examined. Figure 5a shows the amperometric response curves for the reduction of H2O2 examined at −0.05 V by successive addition of 10 μM H2O2 into the phosphate buffer (pH 7.4). Usually, the amperometric current response exhibited a stepwise increase upon addition of H2O2 and reached equilibrium within 2 s, for the electrodes examined in this study. The electrode modified with CNT alone did not favor the reduction of H2O2 at −0.05 V. In contrast, the electrode modified with PB only showed activity of H2O2 reduction. Interestingly, a much enhanced current response was observed for the GC/CNT/PB modified electrode, demonstrating the synergistic effects of PB and CNT. The GC/CNT/PB electrode responded more sensitively to H2O2, and showed a three-fold increase in response current compared with that for the GC/PB electrode. The GC/CNT/PB electrode can be applied for a practical determination of H2O2.

View Article: PubMed Central - PubMed

ABSTRACT

A simple method has been developed for the spontaneous deposition of Prussian blue (PB) particles from a solution containing only ferricyanide ions onto conducting substrates such as indium tin oxide glass, glassy carbon disk and carbon nanotube (CNT) materials. Formation of PB deposits was confirmed by ultraviolet-visible absorption spectrometry and electrochemical techniques. The surface morphology of the PB particles deposited on the substrates was examined by atomic force microscopy and scanning electron microscopy. CNT/PB composite modified glassy carbon electrodes exhibited an electrocatalytic property for hydrogen peroxide reduction. These modified electrodes exhibited a high sensitivity for electrocatalytic reduction of hydrogen peroxide at −0.05 V (vs. Ag/AgCl), probably due to the synergistic effect of CNT with PB. Then, CNT/PB modified electrodes were further developed as amperometric glucose biosensors. These biosensors offered a linear response to glucose concentration from 0.1 to 0.9 mM with good selectivity, high sensitivity of 0.102 A M−1 cm−2 and short response time (within 2 s) at a negative operation potential of −0.05 V (vs. Ag/AgCl). The detection limit was estimated to be 0.01 mM at a signal-to-noise ratio of 3.

No MeSH data available.