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
Polymers Based on Boron?
18.01.2018 | Julius-Maximilians-Universität Würzburg
Bioengineered soft microfibers improve T-cell production
18.01.2018 | Columbia University School of Engineering and Applied Science
What enables electrons to be transferred swiftly, for example during photosynthesis? An interdisciplinary team of researchers has worked out the details of how...
For the first time, scientists have precisely measured the effective electrical charge of a single molecule in solution. This fundamental insight of an SNSF Professor could also pave the way for future medical diagnostics.
Electrical charge is one of the key properties that allows molecules to interact. Life itself depends on this phenomenon: many biological processes involve...
At the JEC World Composite Show in Paris in March 2018, the Fraunhofer Institute for Laser Technology ILT will be focusing on the latest trends and innovations in laser machining of composites. Among other things, researchers at the booth shared with the Aachen Center for Integrative Lightweight Production (AZL) will demonstrate how lasers can be used for joining, structuring, cutting and drilling composite materials.
No other industry has attracted as much public attention to composite materials as the automotive industry, which along with the aerospace industry is a driver...
Scientists at Tokyo Institute of Technology (Tokyo Tech) and Tohoku University have developed high-quality GFO epitaxial films and systematically investigated their ferroelectric and ferromagnetic properties. They also demonstrated the room-temperature magnetocapacitance effects of these GFO thin films.
Multiferroic materials show magnetically driven ferroelectricity. They are attracting increasing attention because of their fascinating properties such as...
The oceans are the largest global heat reservoir. As a result of man-made global warming, the temperature in the global climate system increases; around 90% of...
08.01.2018 | Event News
11.12.2017 | Event News
08.12.2017 | Event News
18.01.2018 | Life Sciences
18.01.2018 | Life Sciences
18.01.2018 | Earth Sciences