Protocols > Antibiotic Concentrations

Antibiotic concentrations for E. coli selection

Antibiotic Concentrations

The following list shows recommended antibiotic concentrations for LB media or agar plates.

• AntibioticConcentration
• Ampicillin100 μg/mL
• Bleocin5 μg/mL
• Carbenicillin100 μg/mL
• Chloramphenicol25 μg/mL
• Coumermycin25 μg/mL
• Gentamycin10 μg/mL
• Kanamycin50 μg/mL
• Spectinomycin50 μg/mL
• Tetracycline10 μg/mL

Example: To make 100 mL of LB/ampicillin growth media, add 100 μL of a 100 mg/mL ampicillin stock (1000X stock) to 100 mL of LB.

Reagent List: Antibiotics

Unless otherwise indicated, the antibiotic powder can be dissolved in H20. Addgene recommends making 1000X stock solutions and storing aliquots at -20°C.

• ReagentCatalog Number
• AmpicillinEMD Chemicals #171254
• BleocinEMD Chemicals #203408
• CarbenicillinEMD Chemicals #205805
• ChloramphenicolEMD Chemicals #220551 (dissolve with EtOH)
• CoumermycinSigma #C9270 (dissolve with DMSO)
• GentamycinEMD Chemicals #345814
• KanamycinEMD Chemicals # 420311
• SpectinomycinEMD Chemicals # 567570
• TetracyclineEMD Chemicals # 583411

Please note that the catalog numbers given in the list above are only examples, and there are many additional companies that supply these reagents.