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June 19, 2021 at 08:38 #2016EKKeymasterJune 19, 2021 at 08:38 #2017EKKeymasterJune 19, 2021 at 08:39 #2018EKKeymasterJune 19, 2021 at 08:39 #2019EKKeymaster
Directory of info in regarding Assimilation and Mutation by NanoGentic Engineering
These have been with us since the industrial revolution and since the early 50’s these particulates were called ultrafine particles that were released into the environment~ and over the years through increased releasing of chemicals these particulate matter have interacted in the atmosphere producing chemistry that is not even listed in the periodic table. The EPA hijacked the research when doing the enviromental test~ when the tested for specific pollutants they hid the facts that when you combine the different pollutants they can react and change and interact with the host of chemicals that were being released ~ the carbon the sunlight( photonics) the EMF of the planet~ the bacterium and mold and fungi and algae and viruses all would react and share ions and mutate and eventually return to the earth impacting the environment through different pathological ways and would alter or mutate the planets genetic code even in different life forms. The aquatic~ the earth based life would eventually consume the vegetation or each other if they were carnivorous and would then to begin the mutations in the genetic code
Fullerenes and NanoAssmebly
These are constructs and templates that are utilized in several fashions to construct~ repair~ assemble~ and deliver it’s program to a designated area to fulfil a building or an assembly of materials or to to deliver materials and or pharma agents to embed them further into the DNA of the host . The repercussions on this is that it causes Mutations to occur in the system to imbalance the communications with the cells and over load the cells with the particulates~ consider these are on a nano scale meaning thousands can fill a cell and oxidize the cells eventually killing the cells and utilizing the dna from the cells to further the mutating effects of it’s replication. The reality is that this is also coming down from the sky as a aerosol from the past and the current chemtrails which are all sefl assembling carbon nanotubes that perpetuate there spread and with it the payload of materials embedded in the fullerene such as thorium~ strontium~ barium~ aluminum ~ lithium~ nanosilver~ styrene~ polymers~ liposomes~ hydrogels which both act as a transport mechanism into the fats ( lipo) and into the fluids ( hydro)
Nano Assimilation and Replication
This is an image on how the assembling and and developing a network of assembling using origami DNA to construct a more centralized construct or a nucleus where conduits of graphene form to make tunnels and venues for self assembling of bots or to further the construct and to increase the network where quantm dots can move and moderate and monitor and with the differing lights they can express would show the areas of monitor and information being collected. This will collect in the cells causing furhter mutations and as a result cause damage from anything to a lupus like effect to cancer to oxidative stress to genetic or dna damage or assimilation~ this attaches to the myelin sheath and the mitochodria causing this to be integrated into the netowrk using the energy for the body to go into this. DNA can now be programmed with a over a trillion bytes of data and this would use this tech to create a network using the graphene conduits it creates and transport the information throughout it parameter
June 19, 2021 at 08:39 #2020EKKeymaster
Nanomotors could help electronics fix themselves
As electronics grow ever more intricate, so must the tools required to fix them. Anticipating this challenge, scientists turned to the body’s immune system for inspiration and have now built self-propelled nanomotors that can seek out and repair tiny scratches to electronic systems. They could one day lead to flexible batteries, electrodes, solar cells and other gadgets that heal themselves.- The researchers present their work today at the 251st National Meeting & Exposition of the American Chemical Society (ACS).- “Electronic circuits are very sophisticated these days,” says Jinxing Li. “But a crack, even an extremely small one, can interrupt the flow of current and eventually lead to the failure of a device. Traditional electronics can be fixed with soldering, but repairing advanced electronics on a nanoscale requires innovation.” Gadgets will soon be more ubiquitous than ever, appearing in our clothes, implants and accessories, says Li, a Ph.D. candidate in the lab of Joseph Wang, D.Sc., at the University of California at San Diego. But finding ways to fix nanocircuits, battery electrodes or other electronic components when they break remains a challenge – Replacing whole devices or even parts can be tricky or expensive, particularly if they’re integrated in clothes or located in remote places. Creating devices that can fix themselves would be ideal, according to Wang, whose lab develops nanoscale machines. To work toward this goal, his lab and others have turned to nature for ideas.- “If you cut your finger, for example, platelets will automatically localize at the wound location and help start the healing process,” Li says. “So what we wanted to do is create and use extremely small robots to perform the same function, except in an electronic system.” To accomplish this, Wang’s team collaborated with the group of Anna Balazs, Ph.D., who is at the University of Pittsburgh. They designed and built nanoparticles out of gold and platinum that are powered by hydrogen peroxide. The platinum spurs the fuel to break down into water and oxygen, which propels the particles. Testing showed that the nanomotors zoomed over the surface of a broken electronic circuit connected to a light-emitting diode, or LED. When they approached the scratch, they got lodged in it and bridged the gap between the two sides. Because the particles are made of conductive metals, they allowed current to flow again, and the LED lit up.- Li says the nanomotors would be ideal for hard-to-repair electronic components such as the conductive layer of solar cells, which are subject to harsh environmental conditions and prone to scratching. They could also be used to heal flexible sensors and batteries, which the Wang lab is also developing.- Additionally, the same concept with different materials and fuels could be used in medical applications for delivering drugs to specific locations. The lab is also developing new nanomotors that could potentially be deployed in the body to treat different diseases, such as stomach infections.-Story Source-The above post is reprinted from materials provided by American Chemical Society. -American Chemical Society. “Nanomotors could help electronics fix themselves.” ScienceDaily. ScienceDaily, 14 March 2016. <www.sciencedaily.com/releases/2016/03/160314084817.htm>.
Nanomotors are controlled, for the first time, inside living cells
For the first time, a team of chemists and engineers at Penn State University have placed tiny synthetic motors inside live human cells, propelled them with ultrasonic waves and steered them magnetically. It’s not exactly “Fantastic Voyage,” but it’s close. The nanomotors, which are rocket-shaped metal particles, move around inside the cells, spinning and battering against the cell membrane.
“As these nanomotors move around and bump into structures inside the cells, the live cells show internal mechanical responses that no one has seen before,” said Tom Mallouk, Evan Pugh Professor of Materials Chemistry and Physics at Penn State. “This research is a vivid demonstration that it may be possible to use synthetic nanomotors to study cell biology in new ways. We might be able to use nanomotors to treat cancer and other diseases by mechanically manipulating cells from the inside. Nanomotors could perform intracellular surgery and deliver drugs noninvasively to living tissues.”–The researchers’ findings will be published in Angewandte Chemie International Edition on 10 February 2014. In addition to Mallouk, co-authors include Penn State researchers Wei Wang, Sixing Li, Suzanne Ahmed, and Tony Jun Huang, as well as Lamar Mair of Weinberg Medical Physics in Maryland U.S.A.
Up until now, Mallouk said, nanomotors have been studied only “in vitro” in a laboratory apparatus, not in living human cells. Chemically powered nanomotors first were developed ten years ago at Penn State by a team that included chemist Ayusman Sen and physicist Vincent Crespi, in addition to Mallouk. “Our first-generation motors required toxic fuels and they would not move in biological fluid, so we couldn’t study them in human cells,” Mallouk said. “That limitation was a serious problem.” When Mallouk and French physicist Mauricio Hoyos discovered that nanomotors could be powered by ultrasonic waves, the door was open to studying the motors in living systems.–For their experiments, the team uses HeLa cells, an immortal line of human cervical cancer cells that typically is used in research studies. These cells ingest the nanomotors, which then move around within the cell tissue, powered by ultrasonic waves. At low ultrasonic power, Mallouk explained, the nanomotors have little effect on the cells. But when the power is increased, the nanomotors spring into action, moving around and bumping into organelles — structures within a cell that perform specific functions. The nanomotors can act as egg beaters to essentially homogenize the cell’s contents, or they can act as battering rams to actually puncture the cell membrane.
While ultrasound pulses control whether the nanomotors spin around or whether they move forward, the researchers can control the motors even further by steering them, using magnetic forces. Mallouk and his colleagues also found that the nanomotors can move autonomously — independently of one another — an ability that is important for future applications. “Autonomous motion might help nanomotors selectively destroy the cells that engulf them,” Mallouk said. “If you want these motors to seek out and destroy cancer cells, for example, it’s better to have them move independently. You don’t want a whole mass of them going in one direction.”The ability of nanomotors to affect living cells holds promise for medicine, Mallouk said. “One dream application of ours is Fantastic Voyage-style medicine, where nanomotors would cruise around inside the body, communicating with each other and performing various kinds of diagnoses and therapy. There are lots of applications for controlling particles on this small scale, and understanding how it works is what’s driving us.”-Story Source-The above post is reprinted from materials provided by Penn State. The original item was written by Krista Weidner. Journal Reference-Wei Wang, Sixing Li, Lamar Mair, Suzanne Ahmed, Tony Jun Huang, Thomas E. Mallouk. Acoustic Propulsion of Nanorod Motors Inside Living Cells. Angewandte Chemie International Edition, 2014–Penn State. “Nanomotors are controlled, for the first time, inside living cells.” ScienceDaily. ScienceDaily, 10 February 2014. <www.sciencedaily.com/releases/2014/02/140210095359.htm>.
June 19, 2021 at 08:40 #2021EKKeymaster
Cytotoxicity and Inflammatory Effect of Silver Nanoparticles
in Human Cells
Cytotoxicity and Inflammatory Effect
of Silver Nanoparticles
in Human Cells
Jeong-shin Park, Na Mi Yu, Jinwoo Cheon and In-Hong Choi
Department of Microbiology, College of Medicine;
Department of Chemistry;
Nanomedical NCRC, Yonsei University, Seoul, Korea
- Approaches to practical toxicology tests
to assess nanoparticles
- Cytotoxicity and inflammatory effects
of silver nanoparticles
Nanoparticles and toxicity assay
The rapidly developing field of nanotechnology will result
in exposure of nanoparticles to humans via several routes
(e.g., inhalation, ingestion, skin, etc.). Nanoparticles can
translocate from the route of exposure to other vital
organs and penetrate cells.
- Toxicity studies to determine the deleterious effects of
nanoparticles on living cells are required.
- Due to the nanosize and the nature of agglomeration,
simple standard methods to characterize the biological
effects of nanoparticles are currently unavailable.
- In this study, practical information regarding the optimal in
vitro tests for nanotoxicity were evaluated.
Cosmetics 200nm 200nm 500nm
20 nm (synthetic)
Biological tests Inflammation ØØ Annexin staining,caspase activation ØØCytokine production,activation of
Signaling molecule ØØROS ØØCytotoxicityØØ MTT/CCK-8 ØØ Establishment of in vitro toxicity assay ØØ Identification of mechanisms for toxicity and inflammation
Production & characterization
of physical and chemical properties
In vitro tests for nanoparticles
• U.S NCL
Review in vitro
• Production of
• Assess biological
Assess toxicity tests
Understanding of proper
methods for nanoparticles
Exposure routes of nanomaterials
Skin Respiratory trac Immune System
Cell line Origin Characteristics Respiratory A549 Lung epithelial Proper for cytotoxicity BEAS-2B Bronchial epithelial
Proper for cytokine Production Immune U937
Macrophage Proper for cytotoxicity and
Skin SK-Mel Skin epithelial Proper for cytotoxicity and
A375 Skin epithelial Too fast growing
Standard toxicology tests and silver nanoparticles
Hemolysis Release of
Activation of C3
Standard Inappropriate Leukocyte
Standard CCK-8 In Vitro
Zymosan assay Standard Proper Cytokine
Standard Proper Phagocytosis Proper Cytokine induction Toxicity Oxidative stress Detection of ROS Standard CCK-8 Cytotoxicity (necrosis) Cell viability and
Standard Annexin-V Cytotoxicity
Standard Targeting Cell
N/S N/S TEM, confocal
microscope or other
Characteristics specific to metal nanomaterials
Nanoparticles larger than 100 nm tend to aggregate relatively quickly in vitro when compared to nanoparticles smaller than 100 nm. Fresh samples
within two weeks after synthesis is recommended for tests.
Each standard toxicology method must be verified before use. (ex. interference with a specific wavelength, electrophoresis)
Flow chart for nanotoxicity tests
Small –Nano Particle Size 100nm-Large
Small–Analysis Of Biological — Nano Particle Size 100nm
– Particle size
– Cytokine production
– Leukocyte proliferation
– ROS production
Large— Analysis of chemical/physical
– Particle size
Cytotoxicity of silver nanoparticles
Cell viability (%)
Cell viability (%)
SK-Mel28 (skin) A375 (skin) A549 (lung)
In human cells, epithelial cells from skin or lung, and macrophages, 5 nm and 20 nm silver particles induced stronger cytotoxicity and ROS synthesis than 80 nm
- 5 nm and 20 nm silver particles induced chemokine production, mainly IL-8, MIF and RANTES, while proinflammatory cytokines, IL-1, IL-6 and TNF-α were not induced significantly in the same conditions.
- Some MAP kinase signaling pathways were activated during exposure to silver nanoparticles at lower —concentrations which do not induce cytotoxicity
The toxicity and inflammatory effects of nanoparticles are dependent on their size. In silver nanoparticles smaller than 20 nm induce cytotoxicity significantly in vitro.
June 19, 2021 at 08:40 #2022EKKeymaster
- Nanoparticles induce inflammatory immune responses at lower concentrations and chemokines are the major cytokines induced at early stages of exposure to silver
Atmospheric Aerosols- The Pariculates –Nano-and there effects
Aerosols are minute particles suspended in the atmosphere. When these particles are sufficiently large, we notice their presence as they scatter and absorb sunlight. Their scattering of sunlight can reduce visibility (haze) and redden sunrises and sunsets.
The dispersal of volcanic aerosols has a drastic effect on Earth’s atmosphere. Follow an eruption, large amounts of sulphur dioxide (SO2), hydrochloric acid (HCL) and ash are spewed into Earth’s stratosphere. HCL, in most cases, condenses with water vapor and is rained out of the volcanic cloud formation. SO2 from the cloud is transformed into sulphuric acid, H2SO4. The sulphuric acid quickly condenses, producing aersol particles which linger in the atmosphere for long periods of time. The interaction of chemicals on the surface of aerosols, known as heterogeneous chemistry, and the tendency of aerosols to increase levels of chlorine gas react with nitrogen in the stratopshere, is a prime contributor to stratospheric ozone destruction.
Aerosols interact both directly and indirectly with the Earth’s radiation budget and climate. As a direct effect, the aerosols scatter sunlight directly back into space. As an indirect effect, aerosols in the lower atmosphere can modify the size of cloud particles, changing how the clouds reflect and absorb sunlight, thereby affecting the Earth’s energy budget.
Aerosols also can act as sites for chemical reactions to take place (heterogeneous chemistry). The most significant of these reactions are those that lead to the destruction of stratospheric ozone. During winter in the polar regions, aerosols grow to form polar stratospheric clouds. The large surface areas of these cloud particles provide sites for chemical reactions to take place. These reactions lead to the formation of large amounts of reactive chlorine and, ultimately, to the destruction of ozone in the stratosphere. Evidence now exists that shows similar changes in stratospheric ozone concentrations occur after major volcanic eruptions, like Mt. Pinatubo in 1991, where tons of volcanic aerosols are blown into the atmosphere (Fig. 1).
Three types of aerosols significantly affect the Earth’s climate. The first is the volcanic aerosol layer which forms in the stratosphere after major volcanic eruptions like Mt. Pinatubo. The dominant aerosol layer is actually formed by sulfur dioxide gas which is converted to droplets of sulfuric acid in the stratosphere over the course of a week to several months after the eruption (Fig. 1). Winds in the stratosphere spread the aerosols until they practically cover the globe. Once formed, these aerosols stay in the stratosphere for about two years. They reflect sunlight, reducing the amount of energy reaching the lower atmosphere and the Earth’s surface, cooling them. The relative coolness of 1993 is thought to have been a response to the stratospheric aerosol layer that was produced by the Mt. Pinatubo eruption. In 1995, though several years had passed since the Mt. Pinatubo eruption, remnants of the layer remained in the atmosphere. Data from satellites such as the NASA Langley Stratospheric Aerosol and Gas Experiment II (SAGE II) have enabled scientists to better understand the effects of volcanic aerosols on our atmosphere.
The second type of aerosol that may have a significant effect on climate is desert dust. Pictures from weather satellites often reveal dust veils streaming out over the Atlantic Ocean from the deserts of North Africa. Fallout from these layers has been observed at various locations on the American continent. Similar veils of dust stream off deserts on the Asian continent. The September 1994 Lidar In-space Technology Experiment (LITE), aboard the space shuttle Discovery (STS-64), measured large quantities of desert dust in the lower atmosphere over Africa (Fig. 2). The particles in these dust plumes are minute grains of dirt blown from the desert surface. They are relatively large for atmospheric aerosols and would normally fall out of the atmosphere after a short flight if they were not blown to relatively high altitudes (15,000 ft. and higher) by intense dust storms.
Fig. 1 – LITE Measurements Over Northwestern Africa, Atlas Mountains
Because the dust is composed of minerals, the particles absorb sunlight as well as scatter it. Through absorption of sunlight, the dust particles warm the layer of the atmosphere where they reside. This warmer air is believed to inhibit the formation of storm clouds. Through the suppression of storm clouds and their consequent rain, the dust veil is believed to further desert expansion.
Recent observations of some clouds indicate that they may be absorbing more sunlight than was thought possible. Because of their ability to absorb sunlight, and their transport over large distances, desert aerosols may be the culprit for this additional absorption of sunlight by some clouds.
The third type of aerosol comes from human activities. While a large fraction of human-made aerosols come in the form of smoke from burning tropical forests, the major component comes in the form of sulfate aerosols created by the burning of coal and oil. The concentration of human-made sulfate aerosols in the atmosphere has grown rapidly since the start of the industrial revolution. At current production levels, human-made sulfate aerosols are thought to outweigh the naturally produced sulfate aerosols. The concentration of aerosols is highest in the northern hemisphere where industrial activity is centered. The sulfate aerosols absorb no sunlight but they reflect it, thereby reducing the amount of sunlight reaching the Earth’s surface. Sulfate aerosols are believed to survive in the atmosphere for about 3-5 days.
The sulfate aerosols also enter clouds where they cause the number of cloud droplets to increase but make the droplet sizes smaller. The net effect is to make the clouds reflect more sunlight than they would without the presence of the sulfate aerosols. Pollution from the stacks of ships at sea has been seen to modify the low-lying clouds above them. These changes in the cloud droplets, due to the sulfate aerosols from the ships, have been seen in pictures from weather satellites as a track through a layer of clouds. In addition to making the clouds more reflective, it is also believed that the additional aerosols cause polluted clouds to last longer and reflect more sunlight than non-polluted clouds.
Climatic Effects of Aerosols
Sept. 16, 1994 – Astronaut Carl J. Meade tests the new Simplified Aid for EVA Rescue (SAFER) system 130 nautical miles above Earth. The hardware supporting the LIDAR-in-Space Technology Experiment (LITE) is in the lower right. A TV camera on the Remote Manipulator System arm records the Extravehicular Activity.– The additional reflection caused by pollution aerosols is expected to have an effect on the climate comparable in magnitude to that of increasing concentrations of atmospheric gases. The effect of the aerosols, however, will be opposite to the effect of the increasing atmospheric trace gases – cooling instead of warming the atmosphere.
The warming effect of the greenhouse gases( nano aerosols) is expected to take place everywhere, but the cooling effect of the pollution aerosols will be somewhat regionally dependent, near and downwind of industrial areas. No one knows what the outcome will be of atmospheric warming in some regions and cooling in others. Climate models are still too primitive to provide reliable insight into the possible outcome. Current observations of the buildup are available only for a few locations around the globe and these observations are fragmentary.
Understanding how much sulfur-based pollution is present in the atmosphere is important for understanding the effectiveness of current sulfur dioxide pollution control strategies.
The Removal of Aerosols
It is believed that much of the removal of atmospheric aerosols occurs in the vicinity of large weather systems and high altitude jet streams, where the stratosphere and the lower atmosphere become intertwined and exchange air with each other. In such regions, many pollutant gases in the troposphere can be injected in the stratosphere, affecting the chemistry of the stratosphere. Likewise, in such regions, the ozone in the stratosphere is brought down to the lower atmosphere where it reacts with the pollutant rich air, possibly forming new types of pollution aerosols.
Aerosols As Atmospheric Tracers
Aerosol measurements can also be used as tracers to study how the Earth’s atmosphere moves. Because aerosols change their characteristics very slowly, they make much better tracers for atmospheric motions than a chemical species that may vary its concentration through chemical reactions. Aerosols have been used to study the dynamics of the polar regions, stratospheric transport from low to high latitudes, and the exchange of air between the troposphere and stratosphere.
Charge properties and the ability of carbon nanoparticles to affect the integrity of the blood-brain barrier as well as exhibit chemical effects within the brain have also been studied. Nanoparticles can overcome this physical and electrostatic barrier to the brain.
June 19, 2021 at 08:40 #2023EKKeymaster
New nanomaterial could slide into future soap
A new designer nanomaterial, created by MIT researchers and described in the April 2 online edition of the Proceedings of the National Academy of Sciences , acts like the main ingredient in soaps, shampoos and detergents. —This biological substance may represent a big improvement over chemicals commonly used in the multibillion dollar detergent industry. The research also may lead to novel carriers for dispensing drugs in the body, and may shed light on protein-to-protein interaction and possibly even the origins of life. –Surfactants are oil-based substances that, when dissolved in liquids, reduce surface tension and allow water to wash away dirt. The researchers have created tiny surfactant-like peptides made of amino acids, the building blocks of proteins. –“We are interested in broadening the diversity of the building blocks of self-assembling peptides for scaffolds and biological materials,” wrote authors Shuguang Zhang, associate director of MIT’s Center for Biomedical Engineering ; postdoctoral associate Sylvain Vauthey; and biology graduate student Steve Santoso. Authors also include Haiyan Gong at Boston University’s School of Medicine and Nicki Watson of the Whitehead Institute . “It is anticipated that self-assemblies and fine-tuning of the surfactant peptide building blocks will lead to construction of a wide range of nanostructures, fostering innovative avenues for the development of scaffold and biologically inspired materials,” said Zhang. “This is another example of basic research that can result in unexpected applications in nanobiotechnology and broad applications, such as high-density scaffolds that incorporate inorganic conducting and nonconducting nanomaterials. They also may be able to encapsulate biological substances such as proteins and DNA, as well as create water-insoluble drugs for delivery to human tissues.”
Zhang and other scientists have recently discovered that the 80,000-plus kinds of proteins in our body, when in fragments called peptides, can be tweaked into forming completely new natural materials that may be able to perform a variety of useful functions inside and outside the body. –Peptides can form nonprotein-like structures such as fibers, tubules, sheets and thin layers. They can respond to changes in acidity, mechanical forces, temperature, pressure, electrical and magnetic fields and light. They are stable at temperatures up to 350 C and can be produced up to a ton at a time at affordable cost. They can be programmed to biodegrade, which may be crucial to the environmentally conscious detergent industry. One kind of peptide scaffold has proved to be a good base for regenerating nerve cells.
“The emerging perception is that self-assembling peptides form a new class of materials set to become commercially viable,” Zhang said. -Like biological phospholipids, surfactant peptides have a hydrophobic (water-repelling) tail and hydrophilic (water-absorbing) head. The peptides interact with one another to form rings, which in turn stack into tubes. Each three nanotubes connect with each other, mimicking lipid microtubule structures. But unlike lipids, the lengths and water-repellency of these surfactant-like peptides can be fine-tuned into well-organized, unique structures. —In addition to improving existing cleaning products, these nanostructures may have other chemical engineering uses for materials where traditional surfactants are used. Unlike lipids, it’s possible to modify these kinds of molecules so that it is easy for them to directly couple with inorganic nanocrystals, opening up a variety of possible applications in molecular electronics for interfacing organic, biological and inorganic materials.
HOW LIFE BEGAN
Another advantage of studying glycine-based surfactant peptides is that glycine, aspartic acid and alanine are of particular interest to researchers studying early chemical and molecular life forms. These substances were thought to be present in the prebiotic environment of early Earth and in intergalactic dust.
Glycine is the simplest of the 20 naturally occurring amino acids and most likely to be the predominant amino acid several billion years ago. These amino acids or their derivatives can form polypeptides when subjected to repeated hydration-dehydration cycles, mimicking the conditions of early life on the planet. These simple biochemical building blocks could produce complex life forms over eons of natural selection and evolution. –If peptides consisting of any combination of these amino acids can self-assemble into nanotubes or vesicles, they would have the potential to provide a primitive enclosure for the earliest RNA-based or peptide enzymes. This would facilitate prebiotic molecular evolution by sequestering the rudimentary enzymes in an enclosed or semi-isolated environment. –This work is supported in part by grants from the United States Army Research Office , the Defense Advanced Research Project Agency/Naval Research Laboratories and the National Institutes of Health .
June 19, 2021 at 08:40 #2024EKKeymaster
Chemists create adaptable metallic-cage gels
New materials could be tuned for applications including drug delivery and water filtration.
Anne Trafton | MIT News Office
November 17, 2015
MIT chemists have created a new type of gel by linking metal organic cages with long polymer strands (blue). The red polymer strands, which loop back to the cages, can be used to further customize the gels by adding other molecules.
MIT chemists have created a new material that combines the flexibility of polymer gels with the rigid structure provided by metal-based clusters. The new gels could be well-suited for a range of possible functions, including drug release, gas storage, or water filtration, the researchers say.
These new gels, known as polyMOCs, are a hybrid of two materials called metallogels and metal organic cages. Metallogels, which consist of metals bound to polymer chains, are similar to regular polymer gels in that they are soft and viscoelastic. Metal organic cages (MOCs), on the other hand, have a rigid structure and tend to form crystalline materials.
“One can imagine a class of materials that borrows from both of those, and so has the well-defined, self-assembled structures of the MOCs, but also has the viscoelastic properties of a polymer gel. That’s what we’ve tried to make,” says Jeremiah Johnson, the Roger and Georges Firmenich Assistant Professor of Natural Product Chemistry and the senior author of a paper describing the gels in Nature Chemistry.-The paper’s lead author is Aleksandr Zhukhovitskiy, a graduate student in MIT’s Department of Chemistry.
To create these gels, Johnson and colleagues built on a technique known as metallo-supramolecular assembly. This strategy allows chemists to generate three-dimensional shapes, such as spheres, paddlewheels, or pyramids, by mixing polymers that are attached to molecules called ligands. These ligands are organic compounds that can bind to a metal atom.
In this case, the researchers used a ligand containing two pyridine groups that each can bind to the metal palladium. Each atom of palladium can form bonds with four other ligand molecules, creating a rigid, cage-like structure with 12 palladium centers and 24 ligands. These centers then connect with other metallic cages by flexible polymer linkers, forming a large, self-assembled gel.–While each metal cage can have up to 24 polymer chains attached to it, only four or five of those connect to other metal cages. These extra, unattached chains loop back and attach to their own metal cage. These loops are commonly referred to as “defects,” but the MIT team saw them as an opportunity to enhance the material by replacing some of the ligands on those chains with new functional molecules.–“We can take the ligands that aren’t connected to another cage and swap those out, while keeping the same net number of chains connecting junctions,” Johnson says. “This allows us to make completely different materials in terms of their composition, but they can have the same mechanical properties.”—“By using these clusters of metallic organic cages, they’ve been able to increase the functionality, and this gives the materials very different properties and mechanical behavior,” says Stuart Rowan, a professor of macromolecular science and engineering at Case Western Reserve University who was not involved in the work. “It’s very elegant, fundamental science that opens the door to a whole range of directions.”
In this study, the researchers added a fluorescent molecule called pyrene in place of some of the looped ligands. “When we look at this material under a UV light it’s fluorescent, but mechanically it’s identical to a material without the pyrene ligand. The modulus is the same, the swelling behavior is the same, but now this gel is intensely fluorescent,” Johnson says.
Many possible functions
This technique is general enough that the researchers should be able to add many other types of molecules with different functions, Johnson says. Such gels could be used for drug delivery by designing them to store drug molecules within the metal cages. They could also be used for storing gases such as hydrogen, which would be useful in cars that run on fuel cells. By adding ligands that can grab and isolate heavy metals, these gels could also be adapted for water purification.—“You could imagine attaching all kinds of things onto those extra ligands to adapt the material for applications of interest,”
June 19, 2021 at 08:40 #2025EKKeymaster
Nano Creations Assembly
Viruses can be made to churn out high-tech nanomaterials
Viruses subvert their hosts to pump out masses of new viruses. In an unusual
twist, an MIT researcher reports in the May 3 issue of Science that she used
genetically engineered viruses that are noninfectious to humans to
mass produce tiny materials for next-generation optical, electronic
and magnetic devices.–"We’ve been looking at using genetic tools to grow
semiconductor materials," said author Angela M. Belcher, associate professor of
materials science and engineering and biological engineering. "In this case, we
took advantage of the viruses’ genetic makeup and physical shape to
not only grow the material but also to help them assemble themselves
into liquid crystal structures that are several centimeters long."–
Belcher and colleagues at the University of Texas at Austin are interested in using
the processes by which nature makes materials to design new biological-
electronic hybrid materials that could be used to assemble electronic
materials at the nanoscale. Her research brings together inorganic chemistry,
materials chemistry, biochemistry, molecular biology and electrical engineering.
She will join the MIT Department of Material Science and Engineering and the
Biological Engineering Division of the School of Engineering in September.–
Belcher’s approach is to use systems such as viruses that evolved over millions of
years to work perfectly at the nanoscale, but to convince the viruses to work on
technologically important materials. Belcher’s research team can evolve
the viruses to work on the materials of interest over a period of
months.–Building self-assembling and defect-free two- and three-dimensional
materials on the nanometer scale is essential for the construction of new devices
for optics and electronics. Researchers have been looking at ways to use organic
materials to organize molecules of inorganic materials on the nanoscale.
Fabricating viral films, Belcher said, may provide new pathways for organizing
molecules to help create electronic, optical and magnetic materials.
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