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.
Archive for the 'Molecular Nanotechnology' Category
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
A brief article reviews several types of molecular machines that chemists have built to mimic biology and provide movement for future types of nanotechnology.
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.
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.
Researchers have configured a 3D printer as an inexpensive, automated discovery platform for synthetic chemistry. A road to more complex molecular building blocks for nanotechnology?
A new online game allows players to design RNA molecules. The most promising designs are synthesized, and the players given real-world feedback on how well their designs worked.
The 2013 Foresight Technical Conference: Illuminating Atomic Precision will be held January 11-13, 2013 in Palo Alto, CA USA.
Nanoparticles made from specific DNA and RNA strands, homogeneous in size, composition, and surface chemistry, proved superior to other nanoparticles in silencing gene expression in tumors in mouse experiments.
A theoretical study shows that although thermal noise cannot be used to produce useful motion by mesoscale or macroscale machines, it can be used by nanoscale machines without violating the second law of thermodynamics.
The demonstration that the process of DNA replication is more flexible than thought should make it easier to incorporate unusual amino acids into designed proteins, which might make it easier to design novel protein machines.
Tryptophan residues introduced at various positions in a protein chain identify folding intermediates that are too short-lived to be structurally characterized otherwise.
A variety of protein cage structures have been constructed by designing specific protein domains to self-assemble as atomically precise protein building blocks in defined geometries.
A set of 310 short single-stranded DNA tiles, plus a few additional short sequences for the edges, has been used to form more than a hundred large, complex DNA objects.
Darpa has launched a “Living Foundries” program to bring an engineering perspective to synthetic biology to greatly accelerate progress through standardization and modularization.
Recent interview touches on new Foresight programs and issues in nanotechnology development
Calculations using density functional theory have demonstrated that graphene can be made piezoelectric by adsorbing atoms or molecules on one surface, or by adsorbing different atoms or molecules on each surface.