FOOD SCIENCE ›› 2011, Vol. 32 ›› Issue (12): 251-253.doi: 10.7506/spkx1002-6630-201112055

• Analysis & Detection • Previous Articles     Next Articles

Rapid Inhibitory Kinetic Spectrophotometric Determination of Vitamin C in Healthcare Products

LIU Ying1,TIAN Zhi-zhuang2,ZHU Yi-wen1,JIANG Zi-qing1,SHANG Shao-ming1   

  1. 1. School of Chemical and Material Engineering, Jiangnan University, Wuxi 214122, China; 2. School of Material and Chemical Engineering, Zhengzhou Institute of Light University, Zhengzhou 450002, China
  • Online:2011-06-25 Published:2011-06-10

Abstract: In order to explore a rapid determination method for vitamin C in healthcare products, colorless o-phenylenediamine (o-PD) solution was subjected to oxidation to form a soluble orange-red product by H2O2 as the oxidant and Fe (Ⅱ) as the catalyst in an acidic environment. The maximum absorbance of the product was located at 450 nm. However, ascorbic acid exhibited an obvious inhibitory effect on that reaction system and could result in the decreased absorbance of the product. The reduction of the absorbance was inversely proportional to the concentration of ascorbic acid in the linear range of 4.0 × 10-6-3.0 × 10-4 mol/L, which was suitable for the rapid determination of vitamin C in healthcare products with the advantages including convenient operation, low-cost reagents and instruments, high selectivity and high accuracy.

Key words: o-phenylenediamine, spectrophotometry, hydrogen peroxide, ferrous sulfate, vitamin C

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