L-ascorbic acid, also known as vitamin C is an essential micronutrient for normal growth and maintenance of cultured cells. It is used as a component of many classical and serum-free cell culture media. Functions of L-ascorbic acid in cell culture systems:

. Promotes proliferation of some tumor cell lines as well as primary cells.

. In reactive oxygen species,it acts as a antioxidant.

. Acts as a cofactor in hydroxylation of lysine and proline residues in collagen and is essential for its normal synthesis and secretion

. In combination with other molecules such as dexamethasone, IBMX and beta-glycerophosphate,ascorbic acid regulates the differentiation of mesenchymal stem cells into osteocytes and adipocytes

However, L-ascorbic acid is very unstable in aqueous solutions and at elevated temperatures. Its stability in culture media varies with media composition, oxygen supply, cell type and cell density.

High doses of ascorbic acid may be detrimental to cultured cells, particularly in serum-free media.Consequently, supplementation of media with ascorbic acids should be carefully standardized.