Conflicting Matrigel instructions

I recently received a new vial of cells and the single sheet titled “Allen Cell Collection: Getting Started” states to coat TC plates with Matrigel diluted 1:30. However, the Culture and Freezing Methods for WTC Derived AICS hiPSC Lines documents states that the GFR Matrigel final protein concentration should be 0.337mg/mL. Could you please clarify: are there 2 different Matrigel concentrations used (one for initially thawed cells and one for subsequently passaged cells), or are you working with a lot of GFR Matrigel in which a 1:30 dilution results in a concentration of 0.337mg/mL?

Thank you!

Dear @en2b,

Thank you for reaching out. The matrigel concentration we use is always 0.337mg/mL. The dilution may vary between lots. We make up the same concentration from each lot. Hope this helps. Please reach out if you have more questions.