title: Specific and reversible DNA-directed self-assembly of oil-in-water emulsion droplets.
abstract: Higher-order structures that originate from the specific and reversible DNA-directed self-assembly of microscopic building blocks hold great promise for future technologies. Here, we functionalized biotinylated soft colloid oil-in-water emulsion droplets with biotinylated single-stranded DNA oligonucleotides using streptavidin as an intermediary linker. We show the components of this modular linking system to be stable and to induce sequence-specific aggregation of binary mixtures of emulsion droplets. Three length scales were thereby involved: nanoscale DNA base pairing linking microscopic building blocks resulted in macroscopic aggregates visible to the naked eye. The aggregation process was reversible by changing the temperature and electrolyte concentration and by the addition of competing oligonucleotides. The system was reset and reused by subsequent refunctionalization of the emulsion droplets. DNA-directed self-assembly of oil-in-water emulsion droplets, therefore, offers a solid basis for programmable and recyclable soft materials that undergo structural rearrangements on demand and that range in application from information technology to medicine.
authors.affiliation: Center for Fundamental Living Technology, Department of Physics, Chemistry and Pharmacy,  University of Southern Denmark, 5230 Odense M,  Denmark.
authors.forename: Maik
authors.initials: M
authors.lastname: Hadorn
authors.forename: Eva
authors.initials: E
authors.lastname: Boenzli
authors.forename: Kristian T
authors.initials: KT
authors.lastname: Sørensen
authors.forename: Harold
authors.initials: H
authors.lastname: Fellermann
authors.forename: Peter
authors.initials: P
authors.lastname: Eggenberger Hotz
authors.forename: Martin M
authors.initials: MM
authors.lastname: Hanczyc
mesh_terms: D020029:Base Pairing; D001710:Biotin; D004247:DNA / Q000737:chemistry*; D004655:Emulsions; D046911:Macromolecular Substances / Q000737:chemistry; D008958:Models, Molecular; D010316:Particle Size; D010795:Phthalic Acids; D019809:Streptavidin; D013500:Surface Tension; D014867:Water
chemical_list: D004655:Emulsions; D046911:Macromolecular Substances; D010795:Phthalic Acids; D014867:Water; D001710:Biotin; D004247:DNA; D019809:Streptavidin; C007379:diethyl phthalate