A new way to make gold form inside the cells of a micro-organism is published today in the Institute of Physics journal Nanotechnology. Researchers from the National Chemical Laboratory and the Armed Forces Medical College, both in Pune, India, have been using “green chemistry” to develop an eco-friendly way to make tiny gold particles without using toxic chemicals.
Such gold nanoparticles of uniform size can be used in labelling proteins, nucleic acids and other biomolecules, which could lead to new ways of detecting disease, controlling genes and enzymes, and delivering therapeutic drugs directly to the nucleus of the cell. The technology can also be used in developing nanomaterials and nanoelectronics.
The research group took a micro-organism called Rhodococcus from a fig tree, and exposed it to a liquid containing gold ions (which are electrically charged gold particles, rather than neutral ones). They found that the micro-organism caused the gold ions to gain electrons, thereby forming gold nanoparticles within the micro-organism’s cells. These nanoparticles are more concentrated and more uniform in size than particles biosynthesised by previous methods that used a fungus. Although the exact reaction that causes the gold to form is not yet fully known, the group believe that the Rhodococcus species gives better results because it is a certain type of micro-organism (an actinomycete) that shows characteristics of both bacteria and fungi, rather than just being a fungus.
“I am extremely pleased with the formation of these gold nanoparticles. They are mainly between about nine and twelve nanometres in diameter, with a few larger particles. That’s about eight thousand times smaller than a human hair,” said Dr. Murali Sastry from the National Chemical Laboratory, India. “This is much more uniform than the particles formed using other biological methods. Having uniformly sized particles will be needed if we are to use this method in biodiagnosis using gold nanoparticles or to deliver therapeutic drugs.”
Following the biosynthesis of gold nanoparticles in Rhodococcus species, its cells continued to multiply normally, as the ions used were not toxic to the cells – which is important as more gold would be formed as the cells multiplied.
The group will soon be looking into making the nanoparticles on a large scale, which could be attained by genetically modifying actinomycetes to produce more of the enzymes which cause the gold to form.
Michelle Cain | alfa
Programming cells with computer-like logic
27.07.2017 | Wyss Institute for Biologically Inspired Engineering at Harvard
Identified the component that allows a lethal bacteria to spread resistance to antibiotics
27.07.2017 | Institute for Research in Biomedicine (IRB Barcelona)
Physicists working with researcher Oriol Romero-Isart devised a new simple scheme to theoretically generate arbitrarily short and focused electromagnetic fields. This new tool could be used for precise sensing and in microscopy.
Microwaves, heat radiation, light and X-radiation are examples for electromagnetic waves. Many applications require to focus the electromagnetic fields to...
Strong light-matter coupling in these semiconducting tubes may hold the key to electrically pumped lasers
Light-matter quasi-particles can be generated electrically in semiconducting carbon nanotubes. Material scientists and physicists from Heidelberg University...
Fraunhofer IPA has developed a proximity sensor made from silicone and carbon nanotubes (CNT) which detects objects and determines their position. The materials and printing process used mean that the sensor is extremely flexible, economical and can be used for large surfaces. Industry and research partners can use and further develop this innovation straight away.
At first glance, the proximity sensor appears to be nothing special: a thin, elastic layer of silicone onto which black square surfaces are printed, but these...
3-D shape acquisition using water displacement as the shape sensor for the reconstruction of complex objects
A global team of computer scientists and engineers have developed an innovative technique that more completely reconstructs challenging 3D objects. An ancient...
Physicists have developed a new technique that uses electrical voltages to control the electron spin on a chip. The newly-developed method provides protection from spin decay, meaning that the contained information can be maintained and transmitted over comparatively large distances, as has been demonstrated by a team from the University of Basel’s Department of Physics and the Swiss Nanoscience Institute. The results have been published in Physical Review X.
For several years, researchers have been trying to use the spin of an electron to store and transmit information. The spin of each electron is always coupled...
26.07.2017 | Event News
21.07.2017 | Event News
19.07.2017 | Event News
27.07.2017 | Life Sciences
27.07.2017 | Life Sciences
27.07.2017 | Health and Medicine