Ampicillin Solution, 50mg/ml, is a convenient, ready to use concentrated solution for molecular biology selection applications. It belongs to the group of beta-lactam antibiotics. These antibotics gram-negative bacteria to which E. coli and Salmonella belong. Beta-lactam antibiotic prevent the formation of peptidoglycan, an essential building block of the cell membrane. Thus, preventing growth of cells.  Sterile-filtered using validated 0.2um membrane filters  Molecular Biology Tested, Prepared from Ampicillin Sodium Salt: Potency: , 845-988ug/mg, Working Concentration:, 20-50 ug/ml for E. coli, Identification A & B (I.R.):, To conform to USP, Sterility:, To conform to USP, pH (1%): 9.0±0.6 , Solubility: , Colorless to light yellow, clear, complete. Storage and Stablility: May be stored at 4°C for short-term only. For long-term storage, store at -20°C