| dc.description.abstract |
This study describes the preparation and application of a titanium dioxide modified carbon paste
electrode for ascorbic acid determination in orange fruit samples by square wave voltammetric
method. While the electrochemical behavior of ascorbic acid was investigated using cyclic
voltammetry, square wave voltammetry was used for determination of ascorbic acid in orange
samples collected from selected localities of Ethiopia. Compared to the unmodified carbon paste
electrode, ascorbic acid showed oxidative peak with an enhanced peak current illustrating the
catalytic activity of titanium modified carbon paste electrode towards its oxidation. Under
optimized solution pH and square wave voltammetric parameters, the oxidative peak current
showed linear dependence on the concentration of ascorbic acid in the range 0.3125 to 20 mM
with correlation coefficient (R
2
) of 0.9981. In this study, ascorbic acid content of freshly orange
fruit samples in Asayta local market collected from Metehara, Tisabalima, Saynt and Mekoy
were determined and compared by square wave voltammetric using Titanium dioxide modified
carbon paste working electrode. The Vitamin C content of the studied orange fruits from
Metehara, Tisabalima, Saynt and Mekoy was 68.90, 60.22, 59.90, 33.34 mg/100 mL, respectively
indicating that its content in the sample from Metehara orange being the highest. Recovery
result of 97.8% validated the applicability of the method for the determination of vitamin C in
real samples.
Keywords: Ascorbic Acid, Carbon Paste Electrode, Titanium Dioxide, Square Wave
Voltammetry, Fresh Orange Fruit. |
en_US |