Time-resolved electron spin resonance has been used to study quenching reactions between the antioxidant Vitamin C （VC） and the triplet excited states of 9,10-phenanthrenequinone （PAQ） in ethylene glycol-water （EG-H2O） homogeneous and inhomogeneous reversed micelle solutions. Reversed micelle solutions were used to be the models of physiological environment of biological cell and tissue. In PAQ/EG-H2O homogeneous solution, the excited triplet of PAQ （3PAQ＊） abstracts hydrogen atom from solvent EG. In PAQ/VC/EG-H2O solution, 3pAQ＊ abstracts hydrogen atom not only from solvent EG but also from VC. The quenching rate constant of 3pAQ＊ by VC is close to the diffusion-controlled value of 1.41 × 108 L/（mol.s）. In hexadecyltrimethylammonium bromide （CTAB）/EG-H2O and aerosol OT （AOT）/EG- H2O reversed micelle solutions, 3pAQ＊ and VC react around the water-oil interface of the reversed micelle. Exit of 3pAQ＊ from the lipid phase slows down the quenching reaction. For Triton X-100 （TX-100）/EG-H2O reversed micelle solution, PAQ and VC coexist inside the hydrophilic polyethylene glycol core, and the quenching rate constant of 3pAQ＊ by VC is larger than those in AOT/EG-H2O and CTAB/EG-H2O reversed micelle solutions, even a little larger than that in EG-H2O homogeneous solution. The strong emissive chemically induced dynamic electron polarization of As＇- resulted from the effective TM spin polarization transfer in hydrogen abstraction of 3pAQ＊ from VC.
