Blasticidin S HCl (10 mg/mL)

All of our antibiotics (Geneticin, Zeocin, Hygromycin B, Blasticidin, and Puromycin) can be used together for making multiple stable cell lines. However, kill curves will need to be performed for each combination of antibiotics since sensitivity to a given antibiotic tends to increase when combined with other antibiotics.

For best results, optimal concentrations for selection should be determined empirically in each unique experiment through dose response curves. However, to get a general idea of concentrations that have worked for individual cell types, please click on the following url: http://www.thermofisher.com/us/en/home/life-science/cell-culture/transfection/selection.html or type in “Selection Antibiotics” into our main search on www.thermofisher.com.

Blasticidin: Nucleoside Inhibits protein synthesis in prokaryotic and eukaryotic cells by interfering with peptidyl transfer reaction of protein synthesis, causing early termination of translation.

Geneticin (G418): Aminoglycoside Blocks protein synthesis in mammalian cells by interfering with ribosomal function.

Hygromycin: Aminocyclitol Inhibits protein synthesis by disrupting translocation and promoting mistranslation.

Zeocin: Intercalates with DNA and cleaves it.

We recommend a pH of 7 or less and half the normal amount of NaCl in your LB media or plates.

See the following paper for details on optimal conditions: Yamaguchi et al (1965) Inhibition of Protein Synthesis by Blasticidin S. Journal of Biochemistry (Tokyo) Volume 57: pp 667-677.

When an irreplaceable culture becomes contaminated, researchers may attempt to eliminate or control the contamination.

1. Determine if the contamination is bacteria, fungus, mycoplasma, or yeast. Read more here to view characteristics of each contaminant.
2. Isolate the contaminated culture from other cell lines.
3. Clean incubators and laminar flow hoods with a laboratory disinfectant, and check HEPA filters.
4. Antibiotics and antimycotics at high concentrations can be toxic to some cell lines. Therefore, perform a dose-response test to determine the level at which an antibiotic or antimycotic becomes toxic. This is particularly important when using an antimycotic such as Gibco Fungizone reagent or an antibiotic such as tylosin.

The following is a suggested procedure for determining toxicity levels and decontaminating cultures:

1. Dissociate, count, and dilute the cells in antibiotic-free media. Dilute the cells to the concentration used for regular cell passage.
2. Dispense the cell suspension into a multiwell culture plate or several small flasks. Add the antibiotic of choice to each well in a range of concentrations. For example, we suggest the following concentrations for Gibco Fungizone reagent: 0.25, 0.50, 1.0, 2.0, 4.0, and 8.0 µg/mL.
3. Observe the cells daily for signs of toxicity such as sloughing, appearance of vacuoles, decrease in confluency, and rounding.
4. When the toxic antibiotic level has been determined, culture the cells for two to three passages using the antibiotic at a concentration one- to two-fold lower than the toxic concentration.
5. Culture the cells for one passage in antibiotic-free media.
6. Repeat step 4.
7. Culture the cells in antibiotic-free medium for four to six passages to determine if the contamination has been eliminated.

Find additional tips, troubleshooting help, and resources within our Cell Culture Support Center.