Nonchemically amplified resists possessing cholate moiety for micropatterning of biomolecules

Two novel monomers, containing diazoketo functional groups, cholic acid 3-diazo-3-ethoxycarbonyl-2-oxo-propyl ester methacrylate (CDEOPE-MA) and 2-diazo-6-hydroxy-3-oxo-hexanoic acid ethyl ester methacrylate (DHOHEE-MA), were designed and synthesized for biomolecular patterning applications. The polymers were synthesized by radical copolymerization of CDEOPE-MA, DHOHEE-MA, and γ-butyrolacton-2-yl methacrylate. The patternability of the synthesized photoresist polymers were characterized by their lithographic evaluation. Introduction of cholate-monomer (CDEOPE-MA) seems to enhance the film formability as well as film stability in aqueous medium. DNA oligonucleotide patterning study was performed to demonstrate the applicability of this system for biomolecular patterning.