Penicillin-Streptomycin-Glutamine Solution, 100×, (100 mL)

Penicillin-streptomycin solution mixture is the most commonly used antibiotic to prevent microbial contamination in vitro. Penicillin can interfere with the synthesis of bacterial cell wall, especially for Gram-positive bacteria. Streptomycin could bind to ribosomal ribosome for 30S and inhibit the synthesis of bacterial protein. It was effective for Gram-negative bacteria and Gram-positive bacteria, but especially for Gram-negative bacteria. The combined use of penicillin and streptomycin can prevent most bacterial contamination, but penicillin solution is sensitive to temperature and pH, easy to degrade at room temperature, and needs cryopreservation, the stability of penicillin solution is the most stable when pH is 6.0-6.5. Streptomycin was relatively stable, and pH 5.0-7.5 was the most stable.
L-glutamine is an essential element in cell culture that is not only an energy source of the cells, but also an important substance involved in protein synthesis and nucleic acid metabolism. The deficiency of L-glutamine will lead to poor cell growth and even death. L-glutamine is unstable in solution and easy to degrade spontaneously, so it is necessary to supplement a certain amount of L-glutamine in culture medium to meet the needs of cell growth after a period of time or when cells grow badly.