GlutaminePlus, powder

L-glutamine is an essential amino acid required as an energy and carbon source by virtually all cells in culture. Exhaustion of L-glutamine in cell culture media has been shown to cause both reduced cell viability and productivity. Supplementation of media with L-glutamine products is frequently required to provide additional nutrients for optimal performance of cells in culture. GlutaminePlus is a stable L-glutamine product that offers a more consistent delivery of L-glutamine to cells in culture as compared to L-glutamine.

Normal L-glutamine has a relatively short half-life in solution, showing a temperature-dependent loss of product with time. L-glutamine degrades through an intramolecular cyclization reaction forming, as by-products, pyrrolidone carbonic acid and ammonia in equimolar concentrations. The rate of breakdown increases with increasing temperature and in the presence of phosphate or bicarbonate. Dipeptide derivatives of L-glutamine prevent the intramolecular cyclization reaction associated with solutions of L-glutamine. These derivatives are therefore stable in solution and allow the formulation of cell culture media containing L-glutamine that may be stored at 4°C for extended periods. Solutions containing these derivatives can even be autoclaved without appreciable degradation of the product (30 minutes at 121°C results in approximately 5% loss of the product). The dipeptide derivatives are metabolized within the cells to yield L-glutamine plus the second amino acid. This results in more consistent delivery of L-glutamine to cells in culture and avoids toxic buildup of ammonia in cell cultures. This feature can be especially important for ammonia sensitive cell lines.