Electrons from a scanning tunneling microscope tip turn a five-arm rotor connected via a single ruthenium atom bearing to a tripod anchoring the molecular motor to a gold surface.
Archive for the 'Research' Category
A theoretical proposal for optical tweezers and an experimental optical focusing device both depend upon electromagnetic waves trapped and guided along metal-insulator interfaces. Will these advances provide tools for manipulating molecular building blocks?
In two different sets of experiments a German research group has shown that scaffolded DNA origami can be used to assemble complex structures with precise sub-nanometer positional control, and that constant temperature reaction can greatly increase yields and decrease production times.
One research group working with rotaxanes and another group working with carbon nanotubes have provided two very different solutions to the problem of producing motion via artificial muscles at different scales from the nano to the macro.
A study of a biological molecular machine has shown that the machine functions most effectively when it uses chemical bonds just barely strong enough to survive the power stroke of the machine.
A set of 32-nucleotide single strand DNA bricks was designed so that each can interact independently with four other DNA bricks so that sets of hundreds of bricks can self-assemble into arbitrarily complex 25-nm 3D shapes, each comprising 1000 8-base pair volume elements.
New time-resolved, high-energy Xray studies of mechanochemical (ball milling) reactions take another step toward reducing the gap between current and future machine-phase chemistry.
Five proteins were designed from scratch and found to fold into stable proteins as designed, proving the ability to provide ideal, robust building blocks for artificial protein structures.
A single-electron spin qubit on a phosphorous atom in a conventional silicon computer chip has been coherently manipulated, demonstrating the application of single atom nanotechnology to the development of a scalable platform for a quantum computer.
One possible pathway from current technology to advanced nanotechnology that will comprise atomically precise manufacturing implemented by atomically precise machinery is through adaptation and extension of the complex molecular machine systems evolved by biology. Synthetic biology, which engineers new biological systems and function not evolved in nature, is an intermediate stage along this path. An [...]
Researchers from Johns Hopkins and Northwestern Universities developed a set of shape-tunable DNA-copolymer nanoparticles that incorporate a fixed amount of DNA yet display as much as 1,680-fold difference in transfection efficiency in rat liver studies. The study may shed new light on the importance of shape in nanoparticle-based drug delivery and gene therapy.
Two types of biological molecular motors that run in opposite directions along a protein track can be used in different arrangements to either move a complex DNA cargo along the track or engage in a tug-of-war.
Large molecular cages constructed from metal-organic frameworks have set a record for the greatest surface area in the least mass.
Metal-organic frameworks (MOFs) are back in the news again. A few months ago we cited the use of MOFs by Canadian chemists to self-assemble a molecular wheel on an axis in a solid material. More recently chemists at Northwestern University have used MOFs to set a world record for surface area. From “A world record for highest-surface-area materials“:
Northwestern University researchers have broken a world record by creating two new synthetic materials with the greatest amount of surface areas reported to date.
Named NU-109 and NU-110, the materials belong to a class of crystalline nanostructure known as metal-organic frameworks (MOFs) that are promising vessels for natural-gas and hydrogen storage for vehicles, and for catalysts, chemical sensing, light harvesting, drug delivery, and other uses requiring a large surface area per unit weight.
The materials’ promise lies in their vast internal surface area. If the internal surface area of one NU-110 crystal the size of a grain of salt could be unfolded, the surface area would cover a desktop. …
MOFs are composed of organic linkers held together by metal atoms, resulting in a molecular cage-like structure. The researchers believe they may be able to more than double the surface area of the materials by using less bulky linker units in the materials’ design. …
Beyond their near-term practical applications, Eric Drexler has cited MOFs as potentially useful building blocks in the molecular machine path to molecular manufacturing. Near-term applications may drive the technology development to produce more choices for molecular machine system components.
—James Lewis, PhD
Optimizing the size and charge of nanoparticles engineered from polymers delivers drugs directly to mitochondria, effectively treating cells with drugs for a variety of diseases.
A “cut and paste” method uses an atomic force microscope to assemble protein and DNA molecules to form arbitrarily complex patterns on a surface. Developing this approach to form enzymatic assembly lines could be a path toward a general purpose nanofactory.
Noncontact atomic force microscopy using a tip functionalized with a single molecule provides highly precise measurement of individual chemical bond lengths and bond orders (roughly, bond strength).
A combination of theoretical and experimental work on peptoids, synthetic analogs of proteins, points to the ability to design peptoids with desired structures and functions.
Studies in mice with otherwise fatal blood clots have shown that targeting a clot-busting drug to regions where blood flow is blocked restores circulation and increases survival with a much lower, safer dose of the drug.
Computational insights into a fundamental organic synthesis reaction may lead to the ability to design a catalyst for any desired reaction.
The directed, artificial evolution of genes for enzymes that produce nanoparticles of silicon dioxide and titanium dioxide produced semiconductor structures not seen in nature.