For the selection and maintenance of eukaryotic cells which are stably transfected with vectors that express the neomycin resistance gene. Susceptibility of cells to G418 will vary with the cell type, media, growth conditions, degree of confluency for adherent cells, metabolic rate, and position in the cell cycle; therefore, we suggest performing a full dose response curve for each cell system used. Effective concentrations have been reported from 100 μg/ml up to greater than 5 mg/ml. Solutions of G418 should be filter-sterilized for use in tissue culture. This is the 5g format. For 1 g format see Cat. # 631307.