Determination Of Nafeedta And Tartaric Acid In Food By Sequential Injection Spectrophotometry

This dissertation was mainly concentrated on the determination of NaFeEDTA in iron fortified soy sauce sample and tartaric acid in wines by sequential injection (SI) spectrophotometry. The obtained results were satisfactory.The first section of the dissertation concerned on the review on the principle and the latest development of sequential injection analysis, especially it's applications in food.In the second section, a sequential injection method with photometric detection was reported for the determination of iron in fortified soy sauce sample, which is based on complexation reaction of Iron(III) with thiocyanate to form red complex with a special absorption at 483 nm. The linear range of the calibration curve was 5.0-100μg·mL-1. A 3s detection limit of 1.4μg/mL, a coefficient of variation lower than 2% at 20μg·mL-1 and 60μg·mL-1 level, and a sample throughput of 60 h-1 were obtained. The recovery of NaFeEDTA in soy sauce samples was varied from 95% to 109%. This method was simple, fast, and accurate. The method was successfully applied to the determination of iron in fortified soy sauce samples.In the third section, a sequential injection method with photometric detection was reported for the determination of tartaric acid in wine, which is based on the reaction of tartaric acid with NaVO3 in HAc-NaAc buffer solution to form red complex with a special absorption at 490 nm. The linear range of the calibration curve was 0.02-1.0g·L-1, and the relative standard deviation was less than 1.0%.The fourth section summarized the research and raised some prospect and applications of the proposed methods.