(IJIRSE) International Journal of Innovative Research in Science & Engineering ISSN (Online) 2347-3207 Resolution of Ascorbic Acid in The Presence of Uric Acid by The Montmorillonite K 10 -clay/SDS Modified Carbon Paste Electrode P. Jeevan Jyoti, K. Gangadhara Reddy, B. Sivananda Reddy, Y.Veera Monahara Reddy, G. Madhavi * Department of Chemistry, S.V.U. College of Sciences, Sri Venkateswara University, Tirupati-517502, Andhra Pradesh, India. Corresponding Author E-Mail: gmchem01@gmail.com. Corresponding Author, Tel.: +91-0877-2289303 Abstract:- Montmorillonite K 10 -clay/SDS modified carbon paste electrode was developed for the simultaneous detection of Ascorbic acid in the presence of Uric acid in 0.1 M phosphate buffer solution of pH 7.0. The modified electrode has exhibited a stable and sensitive current response towards the Ascorbic acid and was utilized for the simultaneous detection of Ascorbic acid and Uric acid. When compared with a bare CPE, the modified electrode exhibited a remarkable shift in the oxidation potentials of Ascorbic acid in the cathodic direction. The anodic peak potentials for the Ascorbic acid is 0.299 V in 0.1 M phosphate buffer solution (PBS) at pH 7.0, at modified carbon paste electrode, it was -0.020 V. The Montmorillonite K 10 -clay/SDS modified CPE was also effective for the simultaneous determination of Ascorbic acid and Uric acid in a mixture and resolved the overlapping anodic peaks of these two species into two well defined voltammetry peaks in differential pulse voltammetry. The proposed method showed an excellent stability, reproducibility and is well suited for the analysis of real samples. Keywords- Montmorillonite K 10 -clay; Ascorbic acid; Uric acid; Cyclic voltammetry; Differential pulse voltammetry. I. INTRODUCTION Ascorbic acid, Uric acid and Dopamine are physiologically important components which are widely distributed in the body of many mammals and exhibits message transfer in the brain and defense against the disease among which the Ascorbic acid is a water soluble vitamin and also a compound which takes part in many important life processes. Due to its antioxidant and pH regulator properties, this vitamin is present or added to a variety of food products and pharmaceuticals. Ascorbic acid takes part in several biological reactions. It prevents and treats the scurvy, common cold, mental illness, infertility and cancer. Ascorbic acid plays a unique redox and electrochemical role [1]. Similarly Uric acid (2,6,8–trihydroxypurine, UA) also a major nitrogenous compound in urine, and also a product of purine metabolism in human body and its higher levels leads to many clinical disorders [2]. High levels of UA in the blood (hyperuricemia or Lesch-Nyhan syndrome) are linked with the body disorders like gout, kidney and cardiac problems. Many epidemiological studies have suggested that the elevated serum UA is also a risk factor for cardiovascular disease [3-8]. In the extracellular fluid of the central nervous system, AA and UA are present in very high concentration, while the DA level is over 3 orders of smaller magnitude (< 100 nM) [9]. The simultaneous determination of such compounds in real biological samples is difficult because of redox reactions of both substances at the bare carbon paste electrodes regularly take place at very similar potentials [10] and often suffer from a pronounced fouling effect, which results in rather poor reproducibility and sensitivity. Hence, to explore a simple, accurate and reliable method for the simultaneous determination of uric acid and ascorbic acid became an urgent need. During the last decades, new electrodes using organic molecules as sensing elements have been developed. Due to their ease of construction and low cost, the modified electrodes are most widely used. Also the modification of these electrodes is simple because it only requires mixing the modifier with the carbon paste. In this way, it is possible to add a wide variety of products (inorganic or organic substances [11,12], biomolecules, animal and plant tissues [13]. The traditional analytical techniques like various chromatographic methods are applied for simultaneous determination of UA and AA. In which HPLC with UV [14], MS detection [15,16], GC [17] and HPCE [18] are preferred. Similarly numerous HPLC methods have been developed for the simultaneous determination of AA and UA in serum, plasma, urine and tissues [19,20], but these methods are required costlier instruments, well equipped laboratory and also trainees. Consequently, it has attracted much interest of electrochemist to develop voltammetric sensors for the detection of AA and UA in the extracellular fluid. However, in the assay of AA, the electrochemical methods