Lyophilized polypeptoids with an -OH group were dissolved in dichloroethane (DCE) at 0. annealed at 100 °C for 10 min under vacuum with 10 sccm N2 flow to remove residue solvents and leave a relaxed polymer brush monolayer grafted on the Si substrate. For surface nanopatterns that consist of two polymer brushes, the second polymer brush was backfilled to the exposed Si(SiO2) surface by spin coating, annealing, rinsing, reannealing, following the same procedure as preparing the first polymer brush monolayer that was patterned (note: the backfill of the second polymer brush was performed right after the resist stripping step to minimize the deactivation of the silanol groups on the just exposed Si substrates).