Nanotechnology is at a crossroads.
It is currently both a mainstream industrial raw material found in thousands of everyday products; from textiles to tennis rackets, from cosmetics to car tires.
Yet it is also a cutting-edge technology, where scientific breakthroughs are being made every week. To keep pace with the discoveries being made in the development of nanomaterials, here is a list of the top breakthroughs in nanotechnology for December 2018.
1. Nanotube Lithium Batteries
Lithium metal batteries are much more effective than lithium-ion batteries. They charge faster and hold ten times more power by volume.
However, they are prone to losing their charge due to the growth of dentrites. These tentacle-like growths extend from the lithium metal, eventually piercing the battery’s electrolyte core to reach the cathode causing the battery to fail.
As a result, lithium metal batteries are rarely used in commercial applications.
But now researchers from Rice University in Texas have developed a tangled-nanotube film that effectively ‘quenches’ the growth of dentrites. In tests, the team were able to charge/discharge over 580 cycles on a battery with a sulfurized-carbon cathode, and still retain 99.8% coulombic efficiency (the measure of how well electrons move within an electrochemical system).
The study has since been published in the journal Advanced Materials, where they explain how, “Lithiated multiwall carbon nanotubes (Li‐MWCNTs) [can] act as a controlled Li diffusion interface to suppress the growth of Li dendrites by regulating the Li+ ion flux during charge/discharge cycling at current densities between 2 and 4 mA cm−2.”
2. Novel Nanodrug Delivery System Prevents Cartilage Deterioration.
In the medical field, nanomaterial specialists have developed a drug treatment that shows great promise in preventing cartilage deterioration caused by osteoarthritis. While current drug technology is limited by the thickness of cartilage and the ability of the chemical to disperse effectively through the tissue, the new procedure is far more effective and longer lasting, potentially enabling cartilage regrowth.
As the MIT website reports, “In a study in rats, the researchers showed that delivering an experimental drug called insulin-like growth factor 1 (IGF-1) with this new material prevented cartilage breakdown much more effectively than injecting the drug into the joint on its own.”
The challenge set to the researchers was designing a method to apply drugs deep inside the cartilage. As Brett Geiger, an MIT graduate student and the lead author of the paper notes, “[The majority of molecules are] cleared before they are able to move through much of the cartilage.”
The breakthrough was made when the team looked at ways to use nanotechnology to create sphere-shaped molecules with branched structures emitting from a central core. Each of the branches (called dendrimers) has a positive electrical charge at its tip, which helps it to bind to the negatively charged cartilage tissue.
The tips also include a “a short flexible, water-loving polymer, known as PEG, that can swing around on the surface and partially cover the positive charge.” Molecules of the treatment drug IGF-1 are also attached to the surface.
When injected on to the surface of the cartilage the positive charge prevents the molecules from being washed away. Meanwhile, “Thanks to the flexible PEG chains on the surface that cover and uncover charge as they move, the molecules can briefly detach from cartilage, enabling them to move deeper into the tissue.”
When the new procedure was tested on the knee joints of rats, they found that the molecule’s half-life had improved ten-fold to about four days. Additionally, the concentration of the drug remained therapeutically effective for a further 30 days.
While the team are quick to note that previous breakthroughs in cartilage pharmaceuticals that worked on animals have not proven effective in humans the improved dispersal rate of this nanotechnology may allow for similar breakthroughs in other parts of the body.
As Paula Hammond, head of MIT’s Department of Chemical Engineering, a member of MIT’s Koch Institute for Integrative Cancer Research, and the senior author of the study, explains, “This is a way to get directly to the cells that are experiencing the damage, and to introduce different kinds of therapeutics that might change their behaviour.”
The study has now been published in the journal Science Translational Medicine.
With more than 20 million people suffering from osteoarthritis in the US alone, the impact of cartilage-penetrating nanocarriers will be significant.
3. Dissolvable Graphene.
Nanographene is insoluble in water and organic solvents…until now.
This is because a team of researchers from Kumamoto University (KU) and Tokyo Institute of Technology(Tokyo Tech), have found a way to form a nanographene adlayer that chemically interacts with the underlying substance. They achieved this by simply mixing ‘molecular containers’ that encapsulate water-insoluble molecules with the nanographene in water.
Reporting on the breakthrough, the online scientific journal, Science Daily, described the discovery in very seasonal terms, explaining how the researchers utilized, “Micelle capsules [microscopic bubbles that are both hydrophobic and hydrophilic] to act like presents from Santa Claus, the highly hydrophobic nanographene molecules (like a toy) inside the capsule (wrapping paper) are transported to the surface of a gold substrate underwater (the Christmas tree). The micelle capsules then undergo a change of molecular state (equilibrium) in the acidic aqueous solution. The nanographene that was inside the micelle is then absorbed and organized on the Au substrate.”
While the discovery does not provide any direct product, the technological breakthrough will be significant in the development of numerous nanomaterials, including electronics (such as organic semiconductors and molecular devices).
As project leader Associate Professor Soichiro Yoshimoto of Kumamoto University notes, "The method we developed can also be applied to a group of molecules with a larger chemical structure. We expect to see this work lead to the development of molecular wires, new battery materials, thin film crystal growth from precise molecular designs, and the further elucidation of fundamental physical properties."
The team has now published their findings in the journal Angewandte Chemie International Edition.
Expanding the range of abilities and applications for nanomaterials is a crucial part of this new industry. Like early mankind discovering the properties of fire, iron smelting, and paint making, modern science is learning how minute nanomaterials act in such different ways to their larger equivalents and developing them for real-world solutions.
When this science meets business, then things get very interesting … and profitable. It is at this point that nanotechnology begins to improve the quality of hundreds of thousands of products as well as improving the quality of life for billions of people.
To learn about more real-world applications for nanotechnology you can read other Team Trade blog articles here.