We are trying to transition our iPSCs to a serum free media, how do you recommend weaning and transitioning?


I am assuming you are starting with some fibroblast growth medium like DMEM supplemented with ESC-qualified FBS. If you are using GIBCO Essential 8 medium as your SFM you can transition directly. Essential 8 is designed for feeder free growth. Here is a reference https://www.lifetechnologies.com/us/en/home/references/protocols/cell-culture/stem-cell-protocols/ipsc-protocols/generation-human-induced-pluripotent-stem-cells-fibroblasts.html

If not, There are two ways to do this. Try a sequential adaptation. Assume you are using old media A and want to transition to new media B. Start in media A and know something about the kinetics of growth. Transition to 80%A:20%B grow several passages then move to 60%A:40%B then 40%A:60%B and so on until your cells are in 100new medium B. The other method involves removing 50% of the old media and supplementing with 50% the new media. If you are removing serum you will need to coat the dishes with some attachment matrix like geltrex or vitronectin if you want attachment.