Cinnamate-based DNA photolithography

As demonstrated by means of DNA nanoconstructs[1], as well as DNA functionalization of nanoparticles[2-4] and micrometre-scale colloids[5-8], complex self-assembly processes require components to associate with particular partners in a programmable fashion. In many cases the reversibility of the interactions between complementary DNA sequences is an advantage[9]. However, permanently bonding some or all of the complementary pairs may allow for flexibility in design and construction[10]. Here, we show that the substitution of a pair of complementary bases by a cinnamate group provides an efficient, addressable, UV light-based method to covalently bond complementary DNA. To show the potential of this approach, we wrote micrometre-scale patterns on a surface via UV light and demonstrate the reversible attachment of conjugated DNA and DNA-coated colloids. Our strategy enables both functional DNA photolithography and multi-step, specific binding in self-assembly processes.