Penicillin-Streptomycin-Amphotericin B 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. Amphotericin B can bind with ergosterol on the membrane of fungi, leading to damage of the membrane, improvement of permeability, leakage of substances inside the cell, disruption of normal metabolism and bacteriostatic effect, but no effect on bacteria. The combined use of penicillin, streptomycin amphotericin B can prevent most bacterial and fungus 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. Amphotericin B solution is unstable at room temperature, easily destroyed by light, heat and acid, and has the strongest antibacterial effect at pH 6.0-7.5.