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
A Map of the Cell’s Power Station
18.08.2017 | Albert-Ludwigs-Universität Freiburg im Breisgau
On the way to developing a new active ingredient against chronic infections
21.08.2017 | Deutsches Zentrum für Infektionsforschung
Whether you call it effervescent, fizzy, or sparkling, carbonated water is making a comeback as a beverage. Aside from quenching thirst, researchers at the University of Illinois at Urbana-Champaign have discovered a new use for these "bubbly" concoctions that will have major impact on the manufacturer of the world's thinnest, flattest, and one most useful materials -- graphene.
As graphene's popularity grows as an advanced "wonder" material, the speed and quality at which it can be manufactured will be paramount. With that in mind,...
Physicists at the University of Bonn have managed to create optical hollows and more complex patterns into which the light of a Bose-Einstein condensate flows. The creation of such highly low-loss structures for light is a prerequisite for complex light circuits, such as for quantum information processing for a new generation of computers. The researchers are now presenting their results in the journal Nature Photonics.
Light particles (photons) occur as tiny, indivisible portions. Many thousands of these light portions can be merged to form a single super-photon if they are...
For the first time, scientists have shown that circular RNA is linked to brain function. When a RNA molecule called Cdr1as was deleted from the genome of mice, the animals had problems filtering out unnecessary information – like patients suffering from neuropsychiatric disorders.
While hundreds of circular RNAs (circRNAs) are abundant in mammalian brains, one big question has remained unanswered: What are they actually good for? In the...
An experimental small satellite has successfully collected and delivered data on a key measurement for predicting changes in Earth's climate.
The Radiometer Assessment using Vertically Aligned Nanotubes (RAVAN) CubeSat was launched into low-Earth orbit on Nov. 11, 2016, in order to test new...
A study led by scientists of the Max Planck Institute for the Structure and Dynamics of Matter (MPSD) at the Center for Free-Electron Laser Science in Hamburg presents evidence of the coexistence of superconductivity and “charge-density-waves” in compounds of the poorly-studied family of bismuthates. This observation opens up new perspectives for a deeper understanding of the phenomenon of high-temperature superconductivity, a topic which is at the core of condensed matter research since more than 30 years. The paper by Nicoletti et al has been published in the PNAS.
Since the beginning of the 20th century, superconductivity had been observed in some metals at temperatures only a few degrees above the absolute zero (minus...
16.08.2017 | Event News
04.08.2017 | Event News
26.07.2017 | Event News
22.08.2017 | Physics and Astronomy
22.08.2017 | Power and Electrical Engineering
22.08.2017 | Medical Engineering