title: Reversible self-assembly and directed assembly of DNA-linked micrometer-sized colloids.
abstract: We present a technique for the directed assembly and self-assembly of micrometer-scale structures based on the control of specific DNA linkages between colloidal particles. The use of DNA links combined with polymer brushes provides an effective way to regulate the range and magnitude of addressable forces between pairs (and further combinations) of different particles. We demonstrate that the autoassembly of alternate microbeads as well as their directed assembly, by using laser tweezers, is reversible. The key to reversibility is preventing the particles from falling into their van der Waals well at close distances. This goal is achieved by the use of adsorbed polymers that limit the number of DNA bridges to one to three between adjacent particles.
authors.affiliation: Department of Physics, Princeton University, Princeton, NJ 08544, USA.
authors.forename: Marie-Pierre
authors.initials: MP
authors.lastname: Valignat
authors.forename: Olivier
authors.initials: O
authors.lastname: Theodoly
authors.forename: John C
authors.initials: JC
authors.lastname: Crocker
authors.forename: William B
authors.initials: WB
authors.lastname: Russel
authors.forename: Paul M
authors.initials: PM
authors.lastname: Chaikin
mesh_terms: D001483:Base Sequence; D001665:Binding Sites; D055598:Chemical Phenomena; D002627:Chemistry, Physical; D003102:Colloids; D004247:DNA / Q000737:chemistry*; D066298:In Vitro Techniques; D046911:Macromolecular Substances; D008856:Microscopy, Fluorescence; D008863:Microspheres; D008958:Models, Molecular; D010316:Particle Size; D011137:Polystyrenes; D055672:Static Electricity; D013816:Thermodynamics
chemical_list: D003102:Colloids; D046911:Macromolecular Substances; D011137:Polystyrenes; D004247:DNA