This paper describes an approach to adhere retinal cells on micropatterned polyelectrolyte multilayer (PEM) lines adsorbed on polydimethylsiloxane (PDMS) surfaces, using microfluidic networks. PEMs were patterned on flat oxidized PDMS surfaces by sequentially flowing polyions through microchannels. Polyethyleneimine (PEI) and poly(allylamine hydrochloride) (PAH) were the polyions used as the top layer cellular adhesion material. The microfluidic networks were lifted off after the patterning was completed and retinal cells were seeded on the PEM/PDMS surfaces. The generalized practice of using blocking agents to prevent the adhesion of cells on unpatterned areas was avoided by allowing the PDMS surface to return to its uncharged state after the patterning was completed. Rat retinal cells adhesion on the patterned PEMs was observed 5 h after seeding. Cell viability and morphology on the patterned PEMs were assayed. These materials proved to be non-toxic to the cells used in this study regardless of the number of stacked PEM layers. Phalloidin staining of the cytoskeleton revealed no apparent morphological differences in retinal cells plated on polystyrene or the larger regions of PEI and PAH. Cells were relatively more elongated however when cultured on the PEM lines. This approach provides a simple, fast and inexpensive form of patterning cells onto micrometer-scale features.
Pub Type: Journals
cell micropatterning, microfluidics, neuronal cells, polyelectrolyte multilayers, retinal R28 cells