Microcontact Printing of Polyelectrolytes on Peg Using Unmodified PDMS Stamp for Micropatterning Nanoparticles, DNA, Proteins and Cells

Microcontact printing (μCP) of polyelectrolytes using an unmodified poly(dimethyl siloxane) (PDMS) stamp is a facile and powerful technique for surface micropatterning.     In particular, the printed polyelectrolyte can be used to immobilize biomolecules and live cells. However, only a few polyelectrolytes can be directly printed using the unmodified PDMS stamp. On other hand, poly(ethylene glycol) (PEG)-silane is commonly used to form a self-assembled monolayer on glass surface to inhibit adsorption of molecules or particles to the surface. A relative complex process is typically required to create micropatterned surface containing both adhesive areas and non adhesive PEG-silane-coated areas. Here we report microcontact printing of polyelectrolytes directly on a glass surface coated with a layer of PEG-silane using the unmodified PDMS stamp.      Some of the polyelectrolytes have never been printed using the unmodified PDMS stamp.     The printed structures, which include monolayer, bilayer, and stretched molecular bundles, are stable in aqueous solutions and have been used as templates for micropatterning quantum dot nanoparticles, DNA, proteins, and live cells.