Turning Cells into Reagents: The Preparation of Assay Ready Cells for Routine Use in Bioassays

Assay ready cells are cryopreserved at a highly functional state and can be used in cell-based assay without prior cultivation or cell passaging. Basically, like any other reagent, the cells are applied to the assay instantly after thawing. Introduced initially in the drug discovery process where assay ready Frozen Instant Cells help to streamline cell-based high-throughput screening campaigns, the methodology now has been accepted for a much broader scope of applications and industries. The preparation of assay ready Frozen Instant Cells is not so much a piece of magic but a combination of good cell culture practice, careful handling, and individually optimized cryopreservation protocols. Here, a standard protocol is presented, how HepG2 cells are frozen in an assay ready quality to be used as a reagent in routine cell-based assays.