Hi,

Why do you want to use Poly-L-Lysine instead of Poly-D-Lysine? Some cells secrete proteases which will cleave PLL, leading to detachment of cells. You should check if your cells secrete it, or directly go with PDL.

You should also check which molecular weight of PLL/PDL is suitable for your cells. Available PLL preparations range from 1,000 - 300,000

http://www.sigmaaldrich.com/catalog/search?term=poly+l+lysine&interface=All&N=0&mode=match%20partialmax&lang=de®ion=DE&focus=product (no affiliation)

Our PDL coating protocol:

Dissolve PDL in ddH2O (I know protocols which use 0.1M Borate buffer or PBS, but we didn't see any differences) as a stock solution (e.g. 1.0 mg/ml).

Dilute PDL to working concentration, add 1 ml /6-Well

Incubate at room temperature over night (this varies a lot from lab to lab). 30 minutes of incubation @37°C also works fine for my cells.

Aspirate solution, wash 3 times with ddH2O

Plate your cells

Thank you very much for your advice! I will try that one!