Chemically orthogonal trifunctional Janus beads by photochemical sandwich microcontact printing

The combination of topographic and chemical orthogonality on polymer particles by site selective immobilization of functional thiols via thiol-ene chemistry provides a trifunctional particle surface with azide and acid functionalities on opposing poles and alkenes in the equatorial area. These Janus beads are accessible for site selective orthogonal chemical reactions as well as biomolecular recognition on the same particle.