A5011543080- Advanced biosensing and bioanalysis techniques
- DNA and Nucleic Acid Chemistry
- Bacteriophages and microbial interactions
- RNA Interference and Gene Delivery
- DNA and Biological Computing
- Modular Robots and Swarm Intelligence
- Gold and Silver Nanoparticles Synthesis and Applications
- RNA and protein synthesis mechanisms
- Supramolecular Self-Assembly in Materials
- Molecular Junctions and Nanostructures
- Conducting polymers and applications
- Micro and Nano Robotics
- Nanopore and Nanochannel Transport Studies
- Electrostatics and Colloid Interactions
- Advanced Materials and Mechanics
- Biosensors and Analytical Detection
- Chemical Synthesis and Analysis
- Pickering emulsions and particle stabilization
- Luminescence and Fluorescent Materials
- Advanced Electron Microscopy Techniques and Applications
- Advanced Polymer Synthesis and Characterization
- Molecular Communication and Nanonetworks
- Advanced X-ray Imaging Techniques
- Polymer Surface Interaction Studies
- Click Chemistry and Applications
New York University
2016-2025
Pomona College
2011
Purdue University West Lafayette
2010
Harvard University
2009
Yokohama City University
2002
Osaka University
2000
University of the Sciences
1999
High Energy Accelerator Research Organization
1994
Harbin Institute of Technology
1994
A substantial challenge in engineering molecular motors is designing mechanisms to coordinate the motion between multiple domains of motor so as bias random thermal motion. For bipedal motors, this takes form coordinating movement biped's legs that they can move a synchronized fashion. To address problem, we have constructed an autonomous DNA walker coordinates action its two by cyclically catalyzing hybridization metastable fuel strands. This process leads chemically ratcheted walk along...
Two-dimensional pseudohexagonal trigonal arrays have been constructed by self-assembly from DNA. The motif used is a bulged-junction DNA triangle whose edges and extensions are double crossover (DX) molecules, rather than conventional helices. Experiments were performed to establish whether the success of this system results added stiffness DX molecules or presence two sticky ends at terminus each edge. Removal one end precludes lattice formation, suggesting that it primary factor enabling formation.
A simple and effective way to make DNA patchy particles is reported. small patch of strands "stamped" from a gold surface onto colloidal different sizes by streptavidin-biotin bonds. These provide direction-selective thermoreversible interactions, hence can lead unique assembly protocols structures controlled temperature.
Single nucleotide polymorphisms (SNPs) are the most common genetic variation in human genome. Kinetic methods based on branch migration have proved successful for detecting SNPs because a mispair inhibits progress of direction mispair. We combined effectiveness kinetic with atomic force microscopy DNA origami patterns to produce direct visual readout target contained probe sequence. The contains graphical representations four alphabetic characters, A, T, G and C, symbol containing test...
Precise chiral colloidal assembly A challenge for particle is to bring different colloids together in a controlled and uniform way that goes beyond making lattice structures. Ben Zion et al. used DNA origami pattern particles assemble them into clusters with chirality composition. belts wrapped flat along the curvature of an L-like shape. This meant other achiral particles, each furnished specific complementary belt, could only attach one orientation. Science , this issue p. 633
Reconfigurable structures engineered through DNA hybridization and self-assembly offer both structural dynamic applications in nanotechnology. Here, we have demonstrated that strand displacement of triplex-forming oligonucleotides (TFOs) can be translated to a robust macroscopic crystal by coloring the crystals with covalently attached fluorescent dyes. We show three different types triplex are feasible within bound TFOs removed and/or replaced (a) changing pH from 5 7, (b) addition...
DNA double-crossover (DX) molecules are rigid motifs that contain two double helices linked at different points. It is possible to form hydrogen-bonded two-dimensional crystals from DX and observe those arrays by atomic force microscopy (AFM) [Winfree, E.; Liu, F.; Wenzler, L. A.; Seeman, N. C. Nature 1998, 394, 539−544]. The sticky ends hold the together can be varied, so as include diverse periodic arrangements of in crystal. inclusion extra hairpins designed protrude plane crystal...
DNA nanotubes are cylinder-like structures formed from double-helical molecules whose helix axes fused at least twice by crossovers. It is potentially useful to use such tubes as sheaths around rodlike species that arise in biological systems and nanotechnology. seems easiest obtain sheathing joining two or more components an object rather than attempting thread the through a cavity tube. We report examples of containing specific number helices assembled half-tube components. These six-helix...
Structural DNA nanotechnology combines branched junctions with sticky-ended cohesion to create self-assembling macromolecular architectures. One of the key goals structural is construct three-dimensional (3D) crystalline lattices. Here we present a new motif and strategy that has led assembly 3D lattice. We have determined X-ray crystal structures two related constructs 3.1 Å resolution using bromine-derivatized crystals. The used employs five-nucleotide repeating sequence weaves through...
Complex structures and devices, both natural manmade, are often constructed sequentially. From crystallization to embryogenesis, a nucleus or seed is formed built upon. Sequential assembly allows for initiation, signaling, logical programming, which necessary making enclosed, hierarchical structures. Although biology relies on such schemes, they have not been available in materials science. Here, we demonstrate programmed sequential self-assembly of DNA functionalized emulsions. The droplets...
Abstract DNA is a very useful molecule for the programmed self‐assembly of 2D and 3D nanoscale objects. 1 The design these structures exploits Watson–Crick hybridization strand exchange to stitch linear duplexes into finite assemblies. 2 – 4 dimensions complexes can be increased by over five orders magnitude through cohesive single‐stranded segments (sticky ends). 5 , 6 Methods that exploit sequence addressability nanostructures will enable programmable positioning components in space,...
Sequence-selective recognition of DNA duplexes is important for a wide range applications including regulating gene expression, drug development, and genome editing. Many small molecules can bind with sequence selectivity. It remains as challenge how to reliably conveniently obtain the detailed structural information on DNA–molecule interactions because such critically needed understanding underlying rules interactions. If those were understood, we could design recognize preference intervene...
We describe the self-assembly of a DNA crystal that contains two tensegrity triangle molecules per asymmetric unit. have used X-ray crystallography to determine its structure. In addition, we demonstrated control over colors crystals by attaching either Cy3 dye (pink) or Cy5 (blue-green) components crystal, yielding corresponding colors. Attaching pair dyes yields purple crystal.
Abstract This manuscript reports an effort to stabilize self‐assembled DNA crystals. Owing their weak inter‐unit cohesion, crystals are fragile, which limits the potential applications of such To overcome this problem, another molecule was introduced, binds cohesive sites and stabilizes interactions. The extra interactions greatly improve stability original only stable in solutions high ionic strength (e.g., ≥1.2 M (NH 4 ) 2 SO ); contrast, stabilized can be at strengths as low that a 0.02...
Abstract A 3D array of organic semiconductors was assembled using a DNA scaffold. An octameric aniline molecule (“octaniline”) incorporated into building block based on dimeric tensegrity triangle. The construct self‐assembled to form crystal. Reversible redox conversion between the pernigraniline and leucoemeraldine states octaniline is retained in Protonic doping gave emeraldine salt at pH 5, corresponding conductive polyaniline. Redox cycling within crystal visualized by color changes...
Single-wall carbon nanotubes (SWCNTs) are known to embody many desirable features for nanoelectronic and photonic applications, including excellent electronic optical properties mechanical robustness. To utilize these species in a bottom-up nanotechnological approach, it is necessary be able place them precise absolute positions within larger framework, without disturbing the conduction surface. Although well-known how orient one or two on DNA origami, placement has eluded investigators...
DNA tensegrity triangles self-assemble into rhombohedral three-dimensional crystals via sticky ended cohesion. Crystals containing two-nucleotide (nt) ends (GA:TC) have been reported previously, and those diffracted to 4.9 Å at beamline NSLS-I-X25. Here, we analyze the effect of varying end lengths sequences as well impact 5′- 3′-phosphates on crystal formation resolution. Tensegrity triangle motifs having 1-, 2-, 3-, 4-nt all form crystals. X-ray diffraction data from same reveal that...
This manuscript introduces geometry as a means to program the tile-based DNA self-assembly in two and three dimensions. strategy complements sequence-focused programmable assembly. crystal assembly critically relies on intermotif, sticky-end cohesion, which requires complementarity not only sequence but also geometry. For motifs assemble into crystals, they must be associated with each other proper orientation ensure that geometric hindrance does prevent sticky ends from associating. exactly...