Nanoparticle self-assembly on a DNA-scaffold written by single-molecule cut-and-paste.
Self-assembly guided by molecular recognition has in the past been employed to assemble nanoparticle superstructures like hypercrystals or nanoparticle molecules. An alternative approach, the direct molecule-by-molecule assembly of nanoscale superstructures, was demonstrated recently. Here we present a hybrid approach where we first assemble a pattern of binding sites one-by-one at a surface and then allow different nanoparticles to attach by self-assembly. For this approach, biotin bearing DNA oligomers were picked up from a depot using a cDNA strand bound to an AFM tip. These units were deposited in the target area by hybridization, forming a recognition pattern on this surface. Fluorescent semiconductor nanoparticles conjugated with streptavidin were allowed to assemble on this scaffold and to form the final nanoparticle superstructures.
Puchner
Elias M
EM
Chair for Applied Physics, Ludwig-Maximilians-Universität Munich, Amalienstrasse 54, 80799 Munich.
Kufer
Stefan K
SK
Strackharn
Mathias
M
Stahl
Stefan W
SW
Gaub
Hermann E
HE
D004247:DNA / Q000737:chemistry* / Q000648:ultrastructure; D015342:DNA Probes / Q000737:chemistry; D018625:Microscopy, Atomic Force; D053758:Nanoparticles / Q000737:chemistry* / Q000648:ultrastructure
D015342:DNA Probes; D004247:DNA