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A potentiometric indirect uric acid sensor based on ZnO nanoflakes and immobilized uricase.

Ali SM, Ibupoto ZH, Kashif M, Hashim U, Willander M - Sensors (Basel) (2012)

Bottom Line: The electrochemical response of the ZnO-NF-based sensor vs. a Ag/AgCl reference electrode was found to be linear over a relatively wide logarithmic concentration range (500 nM to 1.5 mM).In addition, the ZnO-NF structures demonstrate vast surface area that allow high enzyme loading which results provided a higher sensitivity.The sensor response was unaffected by normal concentrations of common interferents such as ascorbic acid, glucose, and urea.

View Article: PubMed Central - PubMed

Affiliation: Department of Science and Technology, Linköping University, Campus Norrköping, Norrkoping, Sweden. syeal@itn.liu.se

ABSTRACT
In the present work zinc oxide nanoflakes (ZnO-NF) structures with a wall thickness around 50 to 100 nm were synthesized on a gold coated glass substrate using a low temperature hydrothermal method. The enzyme uricase was electrostatically immobilized in conjunction with Nafion membrane on the surface of well oriented ZnO-NFs, resulting in a sensitive, selective, stable and reproducible uric acid sensor. The electrochemical response of the ZnO-NF-based sensor vs. a Ag/AgCl reference electrode was found to be linear over a relatively wide logarithmic concentration range (500 nM to 1.5 mM). In addition, the ZnO-NF structures demonstrate vast surface area that allow high enzyme loading which results provided a higher sensitivity. The proposed ZnO-NF array-based sensor exhibited a high sensitivity of ~66 mV/ decade in test electrolyte solutions of uric acid, with fast response time. The sensor response was unaffected by normal concentrations of common interferents such as ascorbic acid, glucose, and urea.

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A typical SEM images of ZnO-NFs arrays grown on gold coated glass substrate using low temperature chemical growth. The figure showing (a) the ZnO-NFs arrays as fabricated; (b) with immobilized uricase and (c) the same sensor electrode after measurements.
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f2-sensors-12-02787: A typical SEM images of ZnO-NFs arrays grown on gold coated glass substrate using low temperature chemical growth. The figure showing (a) the ZnO-NFs arrays as fabricated; (b) with immobilized uricase and (c) the same sensor electrode after measurements.

Mentions: The morphological and structural studies were performed by using Scanning Electron Microscopy (SEM). The SEM images of the ZnO-NFs with as fabricated, after enzymes immobilization and after measurements are shown in Figure 2(a–c).


A potentiometric indirect uric acid sensor based on ZnO nanoflakes and immobilized uricase.

Ali SM, Ibupoto ZH, Kashif M, Hashim U, Willander M - Sensors (Basel) (2012)

A typical SEM images of ZnO-NFs arrays grown on gold coated glass substrate using low temperature chemical growth. The figure showing (a) the ZnO-NFs arrays as fabricated; (b) with immobilized uricase and (c) the same sensor electrode after measurements.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC3376584&req=5

f2-sensors-12-02787: A typical SEM images of ZnO-NFs arrays grown on gold coated glass substrate using low temperature chemical growth. The figure showing (a) the ZnO-NFs arrays as fabricated; (b) with immobilized uricase and (c) the same sensor electrode after measurements.
Mentions: The morphological and structural studies were performed by using Scanning Electron Microscopy (SEM). The SEM images of the ZnO-NFs with as fabricated, after enzymes immobilization and after measurements are shown in Figure 2(a–c).

Bottom Line: The electrochemical response of the ZnO-NF-based sensor vs. a Ag/AgCl reference electrode was found to be linear over a relatively wide logarithmic concentration range (500 nM to 1.5 mM).In addition, the ZnO-NF structures demonstrate vast surface area that allow high enzyme loading which results provided a higher sensitivity.The sensor response was unaffected by normal concentrations of common interferents such as ascorbic acid, glucose, and urea.

View Article: PubMed Central - PubMed

Affiliation: Department of Science and Technology, Linköping University, Campus Norrköping, Norrkoping, Sweden. syeal@itn.liu.se

ABSTRACT
In the present work zinc oxide nanoflakes (ZnO-NF) structures with a wall thickness around 50 to 100 nm were synthesized on a gold coated glass substrate using a low temperature hydrothermal method. The enzyme uricase was electrostatically immobilized in conjunction with Nafion membrane on the surface of well oriented ZnO-NFs, resulting in a sensitive, selective, stable and reproducible uric acid sensor. The electrochemical response of the ZnO-NF-based sensor vs. a Ag/AgCl reference electrode was found to be linear over a relatively wide logarithmic concentration range (500 nM to 1.5 mM). In addition, the ZnO-NF structures demonstrate vast surface area that allow high enzyme loading which results provided a higher sensitivity. The proposed ZnO-NF array-based sensor exhibited a high sensitivity of ~66 mV/ decade in test electrolyte solutions of uric acid, with fast response time. The sensor response was unaffected by normal concentrations of common interferents such as ascorbic acid, glucose, and urea.

Show MeSH