# Substrates passivation
Passivation with PLL-PEG (plasma treatment)
PRIMO photopatterning solution is a so-called subtractive technology. The substrate must be coated with an antifouling polymer that prevents adhesion of molecules and cells.
We recommend SuSoS AG PLL(20)‐g[3.5]‐PEG(2) which we distribute or PEG-SVA.
The PRIMO system then degrades this non-adherent layer locally, through the combined action of UV and a photoactivatable reagent (PLPP).
Passivation with PEG-SVA