Kinetic Spectrophotometric Determination of Ascorbic Acid by Using Phenanthroline Agent in Eruca sativa
S. Seckin
Istanbul University Institute of Health Sciences, 34126, Beyazıt, Istanbul, Türkiye.
S. Saglik Aslan
*
Department of Analytical Chemistry, Istanbul University Faculty of Pharmacy, 34116, Beyazıt Istanbul, Türkiye.
*Author to whom correspondence should be addressed.
Abstract
Ascorbic acid is used for treatment in hypovitaminosis, nutritional deficiency, scurvy, gingivitis, Barlow and Basedow diseases. In this study, a simple and sensitive kinetic spectrophotometric method was developed for the determination of ascorbic acid in Eruca sativa. The rate of formation of the product formed as a result of the reaction of ascorbic acid with iron (III) sulfate and phenanthroline reagents was determined by measuring the absorbance at 510 nm wavelength at 5 minute intervals for 60 minutes. The measurement curve prepared from standard ascorbic acid solution is linear in the concentration range of 4.0-6.0 mg/mL. The regression equation obtained from the graph of logarithms of molar concentrations versus logarithms of slopes was found as log (rate) = 2.5721 logC - 9.461 (r=0.9999) according to the initial rate method. The developed method was applied to Eruca sativa samples and the amount of ascorbic acid in fresh leaves was found to be 72.80 mg/100 g.
Keywords: Kinetic spectrophotometry, ascorbic acid, phenanthroline, Eruca sativa