Micropatterning Cell-Substrate Adhesions Using Linear Polyacrylamide as the Blocking Agent

Abstract

INTRODUCTIONRecent developments in micropatterning techniques have facilitated systematic investigations of how cells respond to geometric cues, which likely have an important role in many physiological processes, such as growth and differentiation. Micropatterned substrates also offer technical advantages for cell biological studies by normalizing cell shapes and reducing the variability among cultured cells. In this article, we present a simple, economical micropatterning method that may be easily implemented in most laboratories. We also describe how to treat the substrate with linear polyacrylamide (PAA) to inhibit unwanted cell adhesion. First, glass coverslip surfaces are activated with 3-methacryloxypropyltrimethoxysilane (bind-silane), an approach that was originally used for covalently linking PAA gels to glass plates for SDS-PAGE to prevent gels from shrinking and swelling during staining/destaining. The activated surfaces are then coated with the photoresist SPR-220, exposed to ultraviolet (UV) light through a photomask, and developed to selectively remove UV-exposed photoresist. Finally, linear PAA is grafted onto the exposed areas of the bind-silane substrate (to prevent cell adhesion), and the remaining photoresist is removed to uncover the glass surface, making the unexposed areas available as adhesive areas for cell culture.