The CAP-e assay: Testing antioxidant bioavailability at the cellular level and creating a foundation for further biological testing of natural products.


To present recent advances using the CAP-e cell-based antioxidant protection assay, with regards to its role in natural products testing, its application as a QC tool, and the importance of controlling for inter-assay variability between batches Of cells used for the assay.


We have developed a novel accelerated method for evaluation of cell-based antioxidant protection using erythrocytes, the CAP-e assay. The CAP-e assay was designed to assist the natural products industry when moving from analytical chemistry testing towards more complex biological testing. The method uses assay principles comparable to the Oxygen Radical Absorbance Capacity (ORAC) assay, applies natural products to intact erythrocytes, and specifically measures antioxidants capable Of penetrating into and protecting the cells from free radical damage. The assay can be applied to testing of antioxidant availability to live cells in vitro and documenting antioxidant uptake in vivo. During the past year, we have made progress in several areas, particularly with respect to quality control of the cells used for this assay, including controlling for inter-assay variability.

Poster (pdf)