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Published on: August 9, 2022
Stability of sodium ascorbyl phosphate in the water-glycerol system
Xiaohui Dong1, Ting Zhang1, Hongyuan Wei1
1School of Chemical Engineering and Technology, Tianjin University, Tianjin, 300072, PR China.
Abstract:
Sodium ascorbyl phosphate is a hydrophilic derivative of ascorbic acid with better stability compared to the parent compound. However, sodium ascorbyl phosphate is not as stable in solution as it is in the solid state, and it has been found to degrade, with accompanying discoloration, under the influence of different conditions. Here, the degradation mechanism of sodium ascorbyl phosphate in the water-glycerol system was revealed and the thermal degradation kinetics was shown to follow second-order kinetics. A thermal degradation prediction model was established and successfully fitted to the experimental data. In addition, the stability of sodium ascorbyl phosphate in the water-glycerol system during storage was investigated under different conditions, including changes in concentration, temperature, pH, light and oxygen, and metal ions. Sodium ascorbyl phosphate content was quantitatively measured via HPLC, and the color and pH values of the sample were qualitatively measured using a spectrophotometer and a pH meter, respectively. It was found that temperature and pH are the most important factors affecting the stability of sodium ascorbyl phosphate.
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