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
NYSCF researchers develop novel bioengineering technique for personalized bone grafts
18.07.2018 | New York Stem Cell Foundation
Pollen taxi for bacteria
18.07.2018 | Technische Universität München
For the first time ever, scientists have determined the cosmic origin of highest-energy neutrinos. A research group led by IceCube scientist Elisa Resconi, spokesperson of the Collaborative Research Center SFB1258 at the Technical University of Munich (TUM), provides an important piece of evidence that the particles detected by the IceCube neutrino telescope at the South Pole originate from a galaxy four billion light-years away from Earth.
To rule out other origins with certainty, the team led by neutrino physicist Elisa Resconi from the Technical University of Munich and multi-wavelength...
For the first time a team of researchers have discovered two different phases of magnetic skyrmions in a single material. Physicists of the Technical Universities of Munich and Dresden and the University of Cologne can now better study and understand the properties of these magnetic structures, which are important for both basic research and applications.
Whirlpools are an everyday experience in a bath tub: When the water is drained a circular vortex is formed. Typically, such whirls are rather stable. Similar...
Physicists working with Roland Wester at the University of Innsbruck have investigated if and how chemical reactions can be influenced by targeted vibrational excitation of the reactants. They were able to demonstrate that excitation with a laser beam does not affect the efficiency of a chemical exchange reaction and that the excited molecular group acts only as a spectator in the reaction.
A frequently used reaction in organic chemistry is nucleophilic substitution. It plays, for example, an important role in in the synthesis of new chemical...
Optical spectroscopy allows investigating the energy structure and dynamic properties of complex quantum systems. Researchers from the University of Würzburg present two new approaches of coherent two-dimensional spectroscopy.
"Put an excitation into the system and observe how it evolves." According to physicist Professor Tobias Brixner, this is the credo of optical spectroscopy....
Ultra-short, high-intensity X-ray flashes open the door to the foundations of chemical reactions. Free-electron lasers generate these kinds of pulses, but there is a catch: the pulses vary in duration and energy. An international research team has now presented a solution: Using a ring of 16 detectors and a circularly polarized laser beam, they can determine both factors with attosecond accuracy.
Free-electron lasers (FELs) generate extremely short and intense X-ray flashes. Researchers can use these flashes to resolve structures with diameters on the...
13.07.2018 | Event News
12.07.2018 | Event News
03.07.2018 | Event News
18.07.2018 | Materials Sciences
18.07.2018 | Life Sciences
18.07.2018 | Health and Medicine