Research on Gold Nanoparticles
February 17th, 2007Although colloidal gold has been in use since ancient time and it the use of gold nanoparticles is found in treatment of alternate Ayurvedic medicines. The Ayurvedic system of medicine is the traditional medicine system of India and the use of gold nanoparticles in medicine is described in The Vedas, the oldest writing available in world. The use of gold nanoparticle is also cited from fifth century Rome. In the recent past the interest and research in the application areas of gold nanoparticles is continuously growing up and some of the applications are described as below.
The research on gold nanoparticles has established that these can be used for detection of colorimetric oligonuceotides based on the optical properties of gold nanoparticles. The method has certain advantage over conventional sequence specific DNA detection methods currently applied in the diagnosis of genetic diseases. The advantages include many features such as rapid detection, a colorimetric response, little required instrumentation and overall high sensitivity and reliability.
The most important finding by Maxwell in the year 2002 has opened the area of applications of gold nanoparticles for fluorescence assay. Maxwell and his team reported that gold nanoparticles can detect the DNA sequences (single mutation) based on the quenching of florescence emission of fluorophores that are attached to oligonucleotides. The application areas are useful for detecting any genetic mutation in target DNA and will have lots of advantages over the conventional detection methods.
As the gold nanoparticles has unique optical as well as electronic behavior, these gold particles can be used in biosensors. In the year 1996, Chen added 10 nm to 30 nm gold nanoparticles in an existing glucose biosensors and found an enhancement in glucose oxidase activity. Further he and his team reported that 10 nm gold particle causes more increase in glucose oxidase activity compared to 30 nm gold nanoparticle. Thus it was concluded that glucose sensors containing gold nanoparticles enhances the enzymatic activity and therefore can be useful for DNA sensors.
Nanotechnology in the Automotive Industry
February 11th, 2007Nanoparticle technology is being used in the automotive industry to protect engines and enable them to perform better. Ford Motor company announced recently that it is using a device called the Local Electrode Atom Probe to conduct research into making metals and plastics lighter and stronger. The device works at the atomic scale and is useful for removing atoms from metallic surfaces as well as locating the position of the atoms on those surfaces. This use of Nanotechnology enables Ford to effectively analyze the surfaces of plastics and metals at the molecular level.
One way that Nanoparticles are being used are as “fillers” for metals and plastics, with the effect of increasing the strength of the produced materials while reducing their weight in the process. The end products can then be used to create aluminum castings for engine blocks. The engines perform better as a result. As well, researchers are looking into ways that Nanoparticles can be added to glass and paints to enable them to better withstand radiation and provide self-cleaning mechanisms.
Ford is using Nanoparticles to improve the operating efficiency of car liquids. These Nanoparticles have been reconstituted into liquids called Nanofluids. When poured into engine oil, lubricants, transmission fluids and coolants, the Nanofluids improve the overall properties of the liquids, leading to reduced friction and enabling them to function more effectively at various temperatures.
Given that Ford has had significant financial woes recently, this investment in Nanotechnology is certainly a good sign. Ford is predicting that by 2015, Nanomaterials will be used in 70% of its production materials. Ford may very well become a leader in the automotive industry again.
Science and Technology Committee on Investment in Nanotechnology in UK
February 8th, 2007As per the fifth report of session 2003-04 of House of Commons, science and technology committee has focused on the government investment in stimulating industrial activity and academic research in nanotechnology area. The committee finds that the government plan and investment in the sector are insufficient and higher funding is required to match with the other major International competitions.
The committee also refers the Taylor Report for investing 90 million pounds in the coming six years and suggests establishing a few nanofabrication facilities. The committee feels in the funding a few world class nanotechnology facilities to raise the UK’s nanotechnology profile. The universities and educational institutes needs to develop the educational and research facilities. Committee also feels that research councils should take initiative to funding research into nanoparticle applications especially environmental or health related problems.
The science and technology committee strongly recommends the tax credits to R&D so that the R&D can focus of some of the successful innovations. As there is already a few problems in venture capital as most of the major companies are reluctant to invest huge money in R&D and it is therefore the role of educational institutes and universities becomes large to drive innovations in nanotechnology. The committee therefore feels that the investment as allotted by Taylor Report is insufficient to drive innovations in nanotechnology.
United Nations Weighs in on Nanotechnology
February 8th, 2007Eventually, all governments want to monitor the impact and use of new technology. It is no different with Nanotechnology. The specter and promise of this breakthrough approach to manufacturing has caught the attention of the United Nations, which has chosen to weigh in on the potential environmental health and safety concerns posed by manufacturing with Nanoparticles.
The report is entitled, The 2007 Global Environment Outlook Year Book and it is produced by UNEP (United Nations Environment Program). Over 80 experts from around the world compiled the volume and in it, they discuss the environmental and social concerns and hazards involved with Nanotechnology. Some of the concerns raised address issues such as the possibility that Nanoparticles could be inhaled, penetrate the skin or otherwise create general levels of toxicity in the environment. The report also asks to consider the potential environmental impact of Nanoparticles released into the atmosphere and the soil.
Nanoparticles already being used in manufacturing should be the first focus of dealing with potential problems, according to the report. Since these are already being used in production, it should be easier to conduct tests to assess what kind of impact they are having on the environment.
As one would expect, the recommendations suggested by the United Nations in dealing with the problem head on is to establish a series of treaties or protocols among member nations and industries. By working together, they can establish a set of mutually agreed upon standards to keep Nanotechnology safe while continuing to benefit from its usefulness.
Technology almost always accelerates at a pace faster than government bodies are able to regulate it, and so perhaps it is best that world governments address the impact of Nanotechnology while it is still in its infancy.
Use of bioconjugated silica nanoparticles in bioanalysis
February 5th, 2007In the recent past various scientists have initiated work on the use of bionanomaterials. There is a great potential for luminescent nanoparticles in bioanalysis as these particles have unique optical properties. In comparison to the traditional fluorescence labeling techniques these luminescent nanoparticles labeling methods are much more accurate and provides enhanced detectable signals. To make the effective use of these nanoparticles, conjugation of biomolecules to the luminescent probe is accurately done.
The silica based nanoparticles find its use in bioanalysis if these are conjugated to recognize biocomponents. In the conjugation process, special elements those interact with the analytes are carefully selected. Using various methods these elements can suitably attached to the silica nanoparticle surface. There are several biochemical binding approaches for modifying the silica nanoparticle surfaces to contain functional groups.
These functional groups are useful for further modification in surface and biomolecule immobilization. So far the research has been successfully completed on biochemical groups including amines, carboxyls, thiols, however various other molecules including oligonucleotides, enzymes and other proteins are being used for immobilizing onto the nanoparticles.
The common methods used for synthesis of nanoparticles are Stober and reverse microemulsion methods. The main disadvantage of Stober method of synthesis is that produces relatively large nonuniform nanoparticles, however it takes short time for synthesis. Reverse microemulsion method produces smaller size nanoparticles and therefore this method is widely used for producing nanoparticles. Reverse microemulsion or water in oil emulsion uses large volume of oil and small volume preferably below less than 20% water and surfactants or emulsifiers.
There are a lot of applications where these biconjugated silica nanoparticles can be used. Although the work is still at preliminary stage of research, however in future these can successfully be used in detecting leukemia cells, detection of pathogenic bacteria , DNA analysis and many other biological applications. In the coming decades, the bionanotechnology may take us to the new heights in identifying and monitoring various diseases.
Nanoparticles sold as germ killers to be regulated by EPA
February 2nd, 2007As per the recent news posted at Washington Post on 23rd Nov 06, the environmental protection agency (EPA) has decided to regulate certain products containing nanoparticles of silver. The decision has been taken to avoid unanticipated risk to the environment. Silver in microscopic nanoparticle form is being used widely for various applications including germ or bacteria killer. The decision of environmental protection agency will thus have impact on various products that uses silver containing nanoparticles including air fresheners, shoe liners, storage containers etc.
Many environmentalists were concerned about the risks posed by these silver containing nanoparticles as it may be washed down and kill many beneficial bacteria and thus increases the risk to not only the environment but to human health also. This is one of the first step to look into the beneficial uses of nanotechnology and correctly outweigh the benefits and the risks of the technology to the environment and human health.
In the initial phase only the germ killer using silver nanotechnology have been focused. Environment Protection Agency (EPA) have clarified that any company wishing to sell a specific germ killer will have to provide scientific evidence that the product does not pose any risk to environment. The product will further be evaluated under EPA’s pesticide program and EPA will ensure that the product is not going to damage the aquatic environment.
Nanoparticles: The Golden Bullet for Cancer Treatment
January 27th, 2007Cancer patients who have only had options such as radiation therapy or chemotherapy to treat their disease now have a new choice from the world of Nanotechnology: Nanoparticles that act as as “gold nanobullets” and “nanobombs.” If it sounds like something out of the world of science fiction, it isn’t. In principle Nanoparticles perform the same function as conventional radiation, to attack and destroy the cancerous cells. Nanoparticles promise to accomplish the same task more effectively however.The process used is called “nanophotothermolysis”.
That’s a big word, but it breaks down easily. “Thermo” means heat, and “molysis” means to break down. Photo means light of course, and with the “nano” prefix, it basically means using Nanotechnology to generate enough heat to break down a substance to its constituent components. Directed laser energy is used to heat up the Nanoparticles until they explode, in the aftermath of which localized cancer cells get destroyed without damaging healthy cells nearby.
In order for the therapy to work, the Nanoparticles must target only cancerous cells and avoid healthy cells. The property that identifies a cell as being cancerous is a protein known as epidermal growth factor receptor (EGFR). This protein surrounds the cancerous cell, but is not found in abundant quantities in the healthy cancerous cells. The Nanoparticles attach themselves to the antibody for the EGFR and then destroy the cancer cell without damaging healthy tissue. In these experiments “gold” Nanoparticles were used, and had the effect of making the cancerous cells shine.
Several after effects contribute to the destruction of cancer cells using Nanoparticles. These include acoustic shock waves from the explosion, optical plasma and particle fragmentation. Research continues in this area with promising results for killing cancer cells without destroying healthy cell tissue.
Biodegradable nanomaterials for reverting brain injuries
January 27th, 2007Scientists at MIT (Massachusetts Institute of Technology) have created a synthetic biodegradable nanomaterials that is useful in many regeneration processes such as regenerating the broken neural related activities. There are a number of brain related problems such as hearing problem, speech problem or blindness where the problems are caused by broken neuronal paths. Scientists believe reconnecting these broken pathways will pave the neuronal paths and thus humans will recover from the diseases.
The synthetic biodegradable nanoparticle acts a s a catalyst in regeneration process and substance containing these nanoparticles is also known as SAPNS if applied to the brain injured species will automatically be eliminated. The research at MIT was carried out on hamsters and some tests to verify the claims have already been carried out. Young and adult hamsters were artificially injured on nerve tract or vision system and were thus made blind and immediately applied the substance containing biodegradable nanoparticles.
As per the claims made by scientists, the results were encouraging and the vision of the young and adult hamsters started improving within 24 hours. After six week period the vision returned to 40 to 80 percent of that of the normal hamster. The nanomaterials is expected to do the similar job in humans and it will help restore the sensory related problems in patients suffering from brain strokes or spinal cord injuries.
Racing towards the First NanoComputer: the Quantum Clock is Ticking Away
January 26th, 2007Computer manufacturers seems to be hurtling towards realizing one of the great dreams of Nanotechnology, the creation of the first Nanocomputer. Such a computer, by definition, would use atoms and molecules instead of silicon chips to transmit information. In order to understand how this would work, you have to understand that a computer, at its essence, is little more than a series of switches in an ‘on’ and ‘off’ state. Each switch occupies a position that represents an exponential number. Through a combination of ‘on’ or ‘off’ states, large numbers can be represented. Atoms, of course, cannot be ‘on’ or ‘off’—but they can occupy different positions in space, and this property can be leveraged to duplicate the same switching mechanism in a silicon-based computer. When that day arrives, the Nanocomputer, one that functions solely in the Quantum world, will be here.Before then, however, the computer industry will take incremental steps towards migrating over to this new technology. This will mean using hybrid technology, combining the Nanotechnology with existing silicon-based circuits, to increase the operating capacity and efficiency of computers. Moore’s Law, which states that technology would double every 18 months, would be turned on its head as the advances of Nanotechnology accelerate the pace of technological progress beyond the rate that Gordon Moore predicted.
The industry has shown that it is taking those incremental steps already. Some of the notable achievements include a technique by an IBM research team that claims they were able to transform iron and platinum into a Nanoparticle that can hold a magnetic charge for up to 10 years, making today’s flash drives obsolete. Other research teams, such as Delft University of Technology in the Netherlands, developed their own circuits utilizing Nanotubes as Field Effect Transistors.
Recently, however, the boldest of announcements was made by Intel President and CEO Paul Otellini. He claimed the company was developing a chipset based on 45 nanometer silicon technology, and processors based on this technology would ship in the second half of 2007. At this breakneck pace, the full-fledged Quantum computer will be only a few years away. Read the article here.
Introduction to nanoparticles
January 23rd, 2007There is a special and borderless science that deals with the nanostructural materials. These nanostructural materials are derived from nanoparticles. The uses of these nanostructural materials are immense and there are sufficient evidences that these nanoparticles display distinct characteristics from the microcrystalline structures. There is no scientific field where the nanomaterials are not being investigated and explored to find the advantages of these materials in improving the desired characteristics.
Nanoparticle synthesis is one of the complex processes. There are three main categories of nanoparticle synthesis and these are vapor phase, solution precipitation and solid-state processes. Although all the three are used for synthesis of nanoparticles the more common and widely used process is solid state. The solid-state process is also the cheapest process among all the three processes used for production of micron-sized particles.
In solid state synthesis of nanoparticles generally heat treatment followed by milling is carried out to get an average particle size of 100nm or less. Mechanical milling is one of the most preferred and earliest technique to produce metallic microcrystalline powder. People claims to get a nanoparticle of very small size of up to 30nm particle size by using media milling of very small size of 200 micro meter. There are other commonly preferred milling methods used by different researchers includes dry milling and ball milling techniques.
In vapor-phase synthesis of nanoparticles, the formation of nanoparticles takes place in gas phase. In this synthesis technique the condensation of atoms and molecules is carried out. The vapor phase synthesis is not new and many multinational companies have been using flame reactors for decades for producing large quantities of nanoparticles. The flame reactors were used for forming various nanoparticles such as carbon black and titanium dioxide.
The last and most advanced technique is known as inert gas condensation. Although the technique is costly, it is considered as a controlled process as by this method the exact shape and size of the nanoparticle can be synthesized. In inert gas condensation technique, the nanoparticle as soon as they formed rapidly collide with inert gas in a low-pressure environment and thus smaller and controlled nanoparticles are formed.
