Merck, 4727878001, G-418 Solution

General description
O-2-Amino-2,7-dideoxy-δ-glycero-α-δ-glucoheptopyranosyl[1->4]-O-3-deoxy-4C-methyl-3-[methyl-amino]-β-L-arabinopyranosyl-δ-streptamine, disulfate salt G-418, an aminoglycoside antibiotic, is used as a dominant selection agent in transfection experiments. The antibiotic interferes with the function of 80S ribosomes and blocks protein synthesis in eukaryotic cells. Transfection of neomycin-resistance genes into cells results in resistance to G-418 and enables the cells to grow in culture media containing G-418.
Application
G-418 Solution is used to select eukaryotic cells that are stably transfected with the neomycin resistance gene (neo), and to maintain the phenotype (neor) of resistant cells.
G-418 is also used to eliminate contaminating fibroblasts from mixed cultures.
Biochem/physiol Actions
Mode of Action: G418 blocks polypeptide synthesis and protein elongation by inhibiting synthesis at the 70S and 80S ribosomes.

Antimicrobial Spectrum: G418 selects for cells stably transfected with an iNOS promoter construct and neomycin resistance gene and shows activity against protozoa and helminthes.
Features and Benefits
Convenient sterile-filtered solution for immediate use – saves valuable time and effort, and avoids potential errors arising from the preparation of sterile working stock solution from G-418 powder.
Consistent quality and potency – shows no lot-to-lot variation in its ability to select resistant cells.
Function tested in a cell culture assay - ensures effectiveness.
Very pure, as indicated by TLC and microbiological assays – allows you to use less antibiotic while producing greater selection pressure. Lack of contaminants means minimal toxicity.
Cost effective, since the selected colonies are stable.
Contents
Aqueous solution of G-418, 892 μg/mg, filtered through 0.2μm pore size membrane
Preparation Note
Working concentration: The optimal concentration of G-418 must be determined experimentally and varies with the cell type used.
Active weight: >700μg/mg
Recommended concentration in cell culture: The optimal concentration of G-418 must be determined experimentally; it varies from 100μg/ml to 1mg/ml, depending on the cell type used.
Specific rotation: 104° to 121°, in water (on dry basis, according to USP XXII).
Analysis Note
Purity: = 98%, as shown by TLC.
Function testing: in cell culture.
Other Notes
For life science research only. Not for use in diagnostic procedures.