Such materials could seal blood vessels during surgery and re-open them subsequently.
Materials that self-assemble and self-destruct once their work is done are highly advantageous for a number of applications – as components in temporary data storage systems or for medical devices.
For example, such materials could seal blood vessels during surgery and re-open them subsequently. Dr. Andreas Walther, research group leader at DWI – Leibniz Institute for Interactive Materials in Aachen, developed an aqueous system that uses a single starting point to induce self-assembly formation, whose stability is pre-programmed with a lifetime before disassembly occurs without any additional external signal – hence presenting an artificial self regulation mechanism in closed conditions. Their results are published as this week’s cover article in ‘Nano Letters’.
Biologically inspired principles for synthesis of complex materials are one of Andreas Walther’s key research interests. To allow the preparation of very small, elaborate objects, nanotechnology uses self-assembly. Usually, in man-made self-assemblies, molecular interactions guide tiny building blocks to aggregate into 3D architectures until equilibrium is reached. However, nature goes one step further and prevents certain processes from reaching equilibrium. Assembly competes with disassembly, and self-regulation occurs. For example, microtubules, components of the cytoskeleton, continuously grow, shrink and rearrange. Once they run out of their biological fuel, they will disassemble.
This motivated Andreas Walther and his team to develop an aqueous, closed system, in which the precise balance between assembly reaction and programmed activation of the degradation reaction controls the lifetime of the materials. A single starting injection initiates the whole process, which distinguishes this new approach from current responsive systems that always require a second signal to trigger the disassembly.
The approach uses pH changes to control the process. The scientists press the start button by adding a base and a dormant deactivator. This first rapidly increases the pH and the building blocks – block copolymers, nanoparticles or peptides – then assemble into a three-dimensional structure. At the same time, the change of pH stimulates the dormant deactivator. PhD student Thomas Heuser explains: “The dormant deactivator slowly becomes activated and triggers an offswitch. But it takes a while before the off-switch unfolds its full potential. Depending on the molecular structure of the deactivator, this can be minutes, hours or a whole day. Until then, the self-assembled nanostructures remain stable.”
The Latest on: Self-assembled nanostructures
via Google News
The Latest on: Self-assembled nanostructures
- Three-dimensional superlattice engineering with block copolymer epitaxyon June 19, 2020 at 7:14 am
Three-dimensional (3-D) structures at the nanoscale are important in modern devices, although their fabrication with traditional top-down approaches is complex and expensive. Block copolymers (BCPs) ...
- Three-dimensional superlattice engineering with block copolymer epitaxyon June 12, 2020 at 11:06 am
Analogous to atomic lattices, block copolymers (BCPs) spontaneously form a rich variety of 3D nanostructures and have the potential ... Building on the concept of atomic epitaxy, the self-assembled ...
- Unlocking PNA's superpowers for self-assembling nanostructureson June 12, 2020 at 5:12 am
This means that they can form nanostructures in solvent environments ... virtual invited talk for the Foundations of Nanoscience: Self-Assembled Architectures and Devices (FNANO) 2020 meeting.
- Butterfly gyroid nanostructures as a time-frozen glimpse of intracellular membrane developmenton June 6, 2020 at 5:00 pm
The optical functionality of gyroid materials have been demonstrated in butterfly wing scales (10–15) and in self-assembled (16 ... have proposed a formation mechanism for chitinous nanostructures viz ...
- Butterfly-inspired nanotechnology makes natural-looking pictures on digital screenson June 4, 2020 at 10:51 am
The findings were published in the journal Proceedings of the National Academy of Sciences ("Self-assembled plasmonics for angle-independent ... shape and patterns of reflective metallic ...
- Determining plasmonic hot-carrier energy distributions via single-molecule transport measurementson June 2, 2020 at 5:00 pm
These authors contributed equally to this work. See allHide authors and affiliations Hot-carriers in plasmonic nanostructures, generated via plasmon decay, play key roles in applications like ...
- 2018 Soft Matter and Biophysical Chemistry Award Winneron May 11, 2019 at 9:08 am
Biomimetic nanocomposites incorporating self-assembled nanostructures changed opened the path to use soft matter in photonics.
- Biomaterials and Regenerative Engineeringon March 15, 2019 at 10:25 pm
Research and teaching areas include self-assembled nanostructures, bioelectronics, synthetic biology, bio-membrane dynamics, nanotechnology, controlled drug release, cell-material interactions, ...
- Detection of femtogram amounts of biogenic amines using self-assembled DNA-protein nanostructureson March 13, 2019 at 11:46 pm
Based on the outcome of recent studies of self-assembled protein-DNA nanostructures, which have proven to be highly efficient reagents in IPCR applications 4, Chimera Biotec has enabled IPCR to ...
- Chapter 15: Self-Assembled Ordered Nanostructureson April 3, 2018 at 3:28 am
The processing, characterization and property measurement of the self-organized or self-assembled nanostrutures are a very active, broad and rapidly expanding research area for chemists, physicists, ...
via Bing News