The kinetics for the reaction of ascorbyl palmitate and 4-hydroxy-TEMPO,4-methoxy- TEMPO or 4-hexanoyloxy-TEMPO in CTAB and SDS micelles was studied by ESR spectroscopy. It was found that the behavior of ascorbyl palm...The kinetics for the reaction of ascorbyl palmitate and 4-hydroxy-TEMPO,4-methoxy- TEMPO or 4-hexanoyloxy-TEMPO in CTAB and SDS micelles was studied by ESR spectroscopy. It was found that the behavior of ascorbyl palmitate is remarkably different from ascorbic acid in their antioxidant activity in micelles.The predominant factors governing the activity in micelles involve the lipophilicity of the antioxidant and the oxidant,the charge type of the substrates and the concentra- tion of the surfactant.As high as 2×10~4 fold rate variation was observed by changing the lipophilicity of the antioxidant and the microenvironment of the reaction medium.展开更多
基金This work was supported by the National Natural Science Foundation of China and the State Education Commission.
文摘The kinetics for the reaction of ascorbyl palmitate and 4-hydroxy-TEMPO,4-methoxy- TEMPO or 4-hexanoyloxy-TEMPO in CTAB and SDS micelles was studied by ESR spectroscopy. It was found that the behavior of ascorbyl palmitate is remarkably different from ascorbic acid in their antioxidant activity in micelles.The predominant factors governing the activity in micelles involve the lipophilicity of the antioxidant and the oxidant,the charge type of the substrates and the concentra- tion of the surfactant.As high as 2×10~4 fold rate variation was observed by changing the lipophilicity of the antioxidant and the microenvironment of the reaction medium.