Pluronic™ F-127 (20% Solution in DMSO)

Culture viability should be in the high 90% range for the seed stock that you are maintaining and growing for the transfections. After transfection, the viability will slowly decrease to the lower 90% to 80% range by about 3-6 days post-transfection and can drop more dramatically at 7 days or longer. This is when using our recommended protocol, which does not suggest any media changes or supplementation post-transfection.

A few parameters we recommend checking to assure high culture viability are: pH at ˜7.0, no visible clumping of the cells, CO2 levels at approximately 7-8% (this should be adjusted to achieve the appropriate pH), volume of culture at 40% or less of nominal flask capacity, and incubator temperature at 37 degrees C. If you have a shaker platform setup in your incubator, the platform may generate sufficient heat to increase the temperature of the incubator. We recommend using a thermometer attached to the shaker platform. Use of baffled flasks may help, if insufficient oxygenation of the cultures is suspected. We also recommend handling and storing the culture media properly, as light exposure can result in breakdown of certain media components. If you are using FreeStyle 293 Expression Medium, supplementing with Pluronic reagent is not necessary.

Find additional tips, troubleshooting help, and resources within our Protein Expression Support Center.