Research Article Voltammetric Determination of Ascorbic Acid Content in Cabbage Using Anthraquinone Modified Carbon Paste Electrode T. Alemu , B Zelalem , and N Amare Department of Chemistry, College of Science, Bahir Dar University, Bahir Dar, Ethiopia Correspondence should be addressed to T. Alemu; alexata16@gmail.com Received 25 September 2021; Revised 2 March 2022; Accepted 25 March 2022; Published 27 April 2022 Academic Editor: Bahaddurghatta Eshwaraswamy Kumara Kumara Swamy Copyright © 2022 T. Alemu et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. In this study, a low-cost, sensitive, and efficient voltammetric method based on anthraquinone modified carbon paste electrode was developed for determination of ascorbic acid in cabbage samples. After cyclic voltammetry was used to investigate the electrochemical behavior of ascorbic acid and to study dependence of oxidative peak current on scan rate and pH, square wave voltammetric method was developed for direct determination of ascorbic acid in cabbage samples. In contrast to the unmodified carbon paste electrode, a remarkable enhancement in oxidative peak current at anthraquinone modified carbon paste electrode confirmed electrocatalytic property of the modifier towards oxidation of ascorbic acid. A better correlation coefficient for the dependence of peak current on the square root of scan rate (R 2 =0:9963) than on the scan rate (R 2 =0:9781) indicated that the oxidation of ascorbic acid at anthraquinone modified carbon paste electrode is predominantly governed by diffusion-controlled process. Square wave amplitude, square wave step potential, and square wave frequency are optimized for the investigation of AA in cabbage. The optimized values are 30 mV, 7 mV, and 35 Hz, respectively. Under the optimized method and solution parameters, an excellent linear response was observed between square wave voltammetric peak current of AQMCPE and concentration of ascorbic acid in the range 5 × 10 -5 to 4 × 10 -3 M with a better correlation coefficient (R 2 =0:9993) and detection limit (LOD = 1:84 × 10 -6 M). The ascorbic acid content of the three cabbage samples from three different cabbage growing areas was found in the range 3:686 ± 0:026–8:298 ± 0:011 mg/g of powdered cabbage. Excellent recovery results between 95.042 and 96.139% for spiked ascorbic acid in cabbage samples confirmed the potential applicability of the developed method based on AQMCPE for the determination of ascorbic acid in real samples like cabbage. 1. Introduction Ascorbic acid (AA), also known as vitamin C, is the most common electroactive molecule which exists widely in foods, beverages, animal feed, and pharmaceutical formulations and plays a paramount role as an antioxidant [1–3]. AA (Scheme 1) is water-soluble, slightly alcohol-soluble, and insoluble in chloroform, ether, and benzene [2]. AA plays a key role in body tissue growth and maintains connective tissues, which include bones, blood vessels, and skin mean- while; AA is significant for biological metabolisms such as free radical scavenging and immunity development [3, 4]. AA is one of the food ingredients that plays a key role in supporting the antioxidant barrier of the body, which is best known under the common name vitamin C [5]. Though most animals can endogenously synthesize large quantities of AA, humans do not have the capability to synthesize AA [6], and so, it must be obtained entirely through one’s diet. Therefore, fruits, vegetables, and their products and other AA-rich sources like red and green peppers, broccoli, tomatoes, strawberries, brussels sprouts, etc. [2, 7] are needed to be consumed for the source of AA. The amount of AA may be reduced due to some processing and storage effects such as packaging material, prolonged storage, too high temperature, and light [8, 9]. Because of that, to improve the nutritive value and maintain natural properties, AA is usually added to dietary foods. The amount of AA required in a healthy diet varies with age and gender. According to Health Canada dietary refer- ence intakes, estimated average requirements and recom- mended dietary allowances, respectively, are for children (ages 1-3) 13 and 15 mg, for adult females 60 and 75 mg, Hindawi Journal of Chemistry Volume 2022, Article ID 7154170, 9 pages https://doi.org/10.1155/2022/7154170