While switching to StemMACS iPS-Brew XF colonies do not attach completely. What can I do?

Be patient: Suboptimal attachment is one of the most common problems during the transition phase. Make sure you are using a Rho-associated protein kinase (ROCK) inhibitor (StemMACS Y27632 or StemMACS Thiazovivin). As long as the colonies do not detach completely, let them grow in size and passage the culture 2–3 times in StemMACS iPS-Brew XF, human. You should not see this anymore beyond passage 5.

If you are using single cell splitting, seed at least 120,000 cells per 6-well. Use a matrix that supports strong attachment (e.g., laminin-521).