Mammalian cell cultures on micropatterned surfaces of weak-acid, polyelectrolyte hyperbranched thin films on gold

A four-step soft lithographic process based on micro-contact printing of or ganic monolayers, hyperbranched polymer grafting, and subsequent polymer fu nctionalization results in polymer/n-alkanethiol patterns that direct the g rowth and migration of mammalian cells. The functional units on these surfa ces are three-dimensional cell "corrals" that have walls 52 +/- 2 nm in hei ght and lateral dimensions on the order of 60 mum. The corrals have hydroph obic, methyl-terminated n-alkanethiol bottoms, which promote cell adhesion, and walls consisting of hydrophilic poly(acrylic acid)/poly(ethylene glyco l) layered nanocomposites that inhibit cell growth. Cell viability studies indicate that cells remain viable on the patterned surfaces for up to 21 da ys, and fluorescence microscopy studies of stained cells demonstrate that c ell growth and spreading does not occur outside of the corral boundaries. T his simple, chemically flexible micropatterning method provides spatial con trol over growth of IC-21 murine peritoneal macrophages, human umbilical ve in endothelial cells, and murine hepatocytes.