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Specifications

Selection Anitbiotics
Alpha-Carboxybenzylpenicillin Disodium Salt
C17H16N2O6S·Na2
M.W.: 422.36
Assay (Carbenicillin): >92%
Benzylpenicillin Sodium: 5% Max.
Indo Absorbing Substance: 8% Max. 
Loss on Drying: 6% Max.
pH: 6.0~7.5
Carbenicillin is chemicaly similar to ampicillin. It is active against gram negative organism.
When selecting for resistance to ampicillin , transformed cells should be plated at low density (<104 colonies per 90mm plate), and the plates should not be incubated for more than 20hrs at 37℃. The enzyme beta-lactamase is secreted into the medium from ampicillin-resistant transformants and can rapidly inactivate the antibiotic in regions surrounding the colonies. Thus, plating cells at high density or incubating them for long periods of time results in the appearance of ampicillin-sensitive satellite colonies. This problem is ameliorated, but not completely eliminated, by using carbenicillin rather than ampicillin in selective media and increasing the concentration of antibiotic from 60ug/mL to 100ug/mL. The number of ampicillin-resistant colonies does not increase in linear proportion to the number of cells applied to the plate, perhaps because of growth-inhibiting substances released form the cells killed by the antibiotic. (Molecular Cloning, Cold Spring Harbor Laboratory Press, 3rd Edition)
Stock Conc.: 50mg/mL in H2O/MeOH 1:1, store at -20℃
Working Conc.: 20-60ug/mL
Store at 4℃