The CAP-e assay (Cell-based Antioxidant Protection in Erythrocytes) is a new method for evaluating the antioxidant potential of natural products based on the concept that many such antioxidant products are only of biological relevance if they are able to protect living cells. In other words, it is a cell-based assay for the evaluation of whether antioxidants in natural products are capable of protecting live cells from oxidative damage – it is designed to measure the antioxidant bioavailability of a product at a cellular level.
