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Development of an electrochemical-based aspartate aminotransferase nanoparticle ir-C biosensor for screening of liver diseases.

Hsueh CJ, Wang JH, Dai L, Liu CC - Biosensors (Basel) (2012)

Bottom Line: Aspartate aminotransaminase (AST) is a hepatocelluar enzyme released into the bloodstream when hepatic cells are damaged, resulting in elevated blood levels of AST.This biosensor is capable of measuring AST levels in a phosphate buffer and undiluted human serum over the concentration range of 0 to 0.89 μg/mL AST concentration (corresponding to 0-250 UL-1 specific activity).The biosensor operates at relatively low oxidation potential (+0.3 volt (V) versus the printed Ag/AgCl), minimizing any potential chemical interference in human serum.

View Article: PubMed Central - PubMed

Affiliation: Department of Chemical Engineering and Electronics Design Center, Case Western Reserve University, 10900 Euclid Avenue, Cleveland, OH 44106, USA. cxh300@case.edu.

ABSTRACT
Aspartate aminotransaminase (AST) is a hepatocelluar enzyme released into the bloodstream when hepatic cells are damaged, resulting in elevated blood levels of AST. A single use, disposable biosensor prototype, composed of catalytic iridium nano-particles dispersed on carbon paste, was developed to detect enzymatically-produced H2O2 in AST-mediated reactions. This biosensor is capable of measuring AST levels in a phosphate buffer and undiluted human serum over the concentration range of 0 to 0.89 μg/mL AST concentration (corresponding to 0-250 UL-1 specific activity). The biosensor operates at relatively low oxidation potential (+0.3 volt (V) versus the printed Ag/AgCl), minimizing any potential chemical interference in human serum. The measurements of AST in human serum using the biosensor compared well with those measured by standard hospital spectrophotometric assays. This Ir-C biosensor may be useful for AST measurements in the clinical environment.

No MeSH data available.


Related in: MedlinePlus

(a) Cyclic-voltammetric scans in the absence/presence of reactants in testing solutions: L-alanine and α-ketoglutarate; (b) Cyclic-voltammetric scans for different added species: reactants and products; (c) Cyclic-voltammetric scans for different added species in testing solutions: co-reactants in the absence/presence of 0.356 μg/mL AST and 0.5 µL of 0.05U/µL GluOx.
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biosensors-02-00234-f004: (a) Cyclic-voltammetric scans in the absence/presence of reactants in testing solutions: L-alanine and α-ketoglutarate; (b) Cyclic-voltammetric scans for different added species: reactants and products; (c) Cyclic-voltammetric scans for different added species in testing solutions: co-reactants in the absence/presence of 0.356 μg/mL AST and 0.5 µL of 0.05U/µL GluOx.

Mentions: Cyclic voltammetry was applied to the correlated reactants (L-aspartate and α-ketoglutarate) and products (oxaloacetate and L-glutamate) involved in the AST reaction mechanism shown in Scheme 2. The cyclic voltammetric measurements were carried out in the voltage window of −0.1 V to +0.4 V versus the printed Ag/AgCl reference electrode with a scan rate of 10 mV per second. Figure 4(a,b) shows that there was no contribution to the current output by either chemical. Figure 4(c) shows the detection of AST by measuring the oxidation of H2O2 produced at +0.30 V versus the printed Ag/AgCl.


Development of an electrochemical-based aspartate aminotransferase nanoparticle ir-C biosensor for screening of liver diseases.

Hsueh CJ, Wang JH, Dai L, Liu CC - Biosensors (Basel) (2012)

(a) Cyclic-voltammetric scans in the absence/presence of reactants in testing solutions: L-alanine and α-ketoglutarate; (b) Cyclic-voltammetric scans for different added species: reactants and products; (c) Cyclic-voltammetric scans for different added species in testing solutions: co-reactants in the absence/presence of 0.356 μg/mL AST and 0.5 µL of 0.05U/µL GluOx.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4263573&req=5

biosensors-02-00234-f004: (a) Cyclic-voltammetric scans in the absence/presence of reactants in testing solutions: L-alanine and α-ketoglutarate; (b) Cyclic-voltammetric scans for different added species: reactants and products; (c) Cyclic-voltammetric scans for different added species in testing solutions: co-reactants in the absence/presence of 0.356 μg/mL AST and 0.5 µL of 0.05U/µL GluOx.
Mentions: Cyclic voltammetry was applied to the correlated reactants (L-aspartate and α-ketoglutarate) and products (oxaloacetate and L-glutamate) involved in the AST reaction mechanism shown in Scheme 2. The cyclic voltammetric measurements were carried out in the voltage window of −0.1 V to +0.4 V versus the printed Ag/AgCl reference electrode with a scan rate of 10 mV per second. Figure 4(a,b) shows that there was no contribution to the current output by either chemical. Figure 4(c) shows the detection of AST by measuring the oxidation of H2O2 produced at +0.30 V versus the printed Ag/AgCl.

Bottom Line: Aspartate aminotransaminase (AST) is a hepatocelluar enzyme released into the bloodstream when hepatic cells are damaged, resulting in elevated blood levels of AST.This biosensor is capable of measuring AST levels in a phosphate buffer and undiluted human serum over the concentration range of 0 to 0.89 μg/mL AST concentration (corresponding to 0-250 UL-1 specific activity).The biosensor operates at relatively low oxidation potential (+0.3 volt (V) versus the printed Ag/AgCl), minimizing any potential chemical interference in human serum.

View Article: PubMed Central - PubMed

Affiliation: Department of Chemical Engineering and Electronics Design Center, Case Western Reserve University, 10900 Euclid Avenue, Cleveland, OH 44106, USA. cxh300@case.edu.

ABSTRACT
Aspartate aminotransaminase (AST) is a hepatocelluar enzyme released into the bloodstream when hepatic cells are damaged, resulting in elevated blood levels of AST. A single use, disposable biosensor prototype, composed of catalytic iridium nano-particles dispersed on carbon paste, was developed to detect enzymatically-produced H2O2 in AST-mediated reactions. This biosensor is capable of measuring AST levels in a phosphate buffer and undiluted human serum over the concentration range of 0 to 0.89 μg/mL AST concentration (corresponding to 0-250 UL-1 specific activity). The biosensor operates at relatively low oxidation potential (+0.3 volt (V) versus the printed Ag/AgCl), minimizing any potential chemical interference in human serum. The measurements of AST in human serum using the biosensor compared well with those measured by standard hospital spectrophotometric assays. This Ir-C biosensor may be useful for AST measurements in the clinical environment.

No MeSH data available.


Related in: MedlinePlus