Amperometric sensor for L-ascorbic acid determination based on MnO2 bulk modified screen printed electrode.
A simple biosensor constructed by bulk-modification of carbon ink with manganese dioxide as a mediator was investigated for its ability to serve as amperometric detector for L-ascorbic acid in hydrodynamic mode. The sensor could be operated at pH 5.0 (0.05 M phosphate buffer) and exhibited excellent reproducibility and stability. Optimization of measurement parameters such as applied working potential and pH value were studied in detail. The screen printed electrode exhibited a linear amperometric increase with the concentration of L-ascorbic acid from 50 mg L(-1) to 250 mg L(-1) and gave a (LOD = 3sigma) detection limit of 0.2 mg L(-1) (1.172 micromol L(-1)). The manganese dioxide modified screen printed electrode shows long term stability.
Department of Chemistry, Faculty of Science, University of Sarajevo, Bosnia and Herzegovina.
E
E
Turkusic
V
V
Milicevic
H
H
Tahmiscija
M
M
Vehabovic
S
S
Basic
V
V
Amidzic
D001205:Ascorbic Acid / Q000032:analysis*; D015374:Biosensing Techniques / Q000295:instrumentation* / Q000379:methods / Q000592:standards*; D002138:Calibration; D002244:Carbon; D004563:Electrochemistry; D004566:Electrodes; D017895:Manganese Compounds / Q000494:pharmacology; D010084:Oxidation-Reduction; D010087:Oxides / Q000494:pharmacology; D012680:Sensitivity and Specificity
D017895:Manganese Compounds; D010087:Oxides; D002244:Carbon; D001205:Ascorbic Acid; C016552:manganese dioxide