IRON (III) PHENANTHROLINE COMPLEX INTERCALATED INTO CALCIUM PHOSPHATE AS MEDIATOR FOR AMPEROMETRIC ANALYSIS OF ASCORBIC ACID

• Main Author: SRI RAHAYU (NIM: 20508022), RIA
• Format: Theses
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/12562
• Institution: Institut Teknologi Bandung

Ascorbic acid, known as Vitamin C, is a very important compound for our health, due to its anti-oxidant property. Ascorbic acid cannot be synthesized in the body. But, ascorbic acid can be obtained from fruits, beverages, and food products. Ascorbic acid is also widely used in food and beverages industry to increase product quality. Due to the importance of ascorbic acid, a simple and accurate ascorbic acid analysis method is needed. Several analytical methods for ascorbic acid analysis have been developed, such as iodommetry titration and spectrophotometry. Those methods have some disadvantage. In iodommetry titration, the biggest disadvantages are the use of indicator and determination of end point titration that can cause significant error. In spectrophotometry method, the sample needs special treatment to reduce the effect of matrices that can also absorb or reflect light used in analysis. Voltammetry method is one of fast growing analytical methods because it has some advantages such as short analysis time and low detection limit. However voltammetric analysis of ascorbic acid using carbon paste electrode is impossible because rate of electron transfer of ascorbic acid oxidation on the electrode is slow. The slow rate of electron transfer is shown by wide peak of its cyclic voltamogram. Some modification have been study to increase the rate of ascorbic acid oxidation on the electrode. <br />