Methods to measure lipid antioxidant activity

The present invention provides a selective method for measuring lipid antioxidant activity within a lipid compartment of a sample using lipophilic radical generators and oxidizable lipophilic indicators. The present invention accurately and efficiently determines the total antioxidant activity of a sample in both lipid and aqueous compartments. The methods of the invention can be used for diagnosing and protecting against disorders that arise from excess free radicals present in a subject. The reagents used in the methods of the invention can also be provided in a kit assay.