An Aug. 1, 2013 news item on Nanowerk highlights some ‘green’ chemistry in Australia,
Murdoch University (Australia) researchers have developed a ‘green’ method to create antibacterial gold nanoparticles for potential use in the medical field with the help of common eucalyptus leaves (“Green biosynthesis of gold nanometre scale plates using the leaf extracts from an indigenous Australian plant Eucalyptus macrocarpa”)
The Aug. 1, 2013 Murdoch University news release, which originated the news item, provides more information from the lead researcher about the use of gold nanoparticles in the medical field and about the ‘eucalyptus leaf’ technique,
“Gold nanoparticles have proven to be very versatile across a range of treatments, including in the delivery of double-stranded DNA in the emerging gene therapy area,” Dr Poinern said.
“They can also be passively accumulated in tumours for thermal treatment therapies, where they are heated to damage and kill cancer cells.
“And studies have shown that cancer drugs bonded to the surface of gold nanoparticles can effectively target tumours, improving delivery and minimising treatment durations and the side effects of anticancer drugs.”
Dr Poinern [Dr Gérrard Eddy Poinern, Director of the Murdoch Applied Nanotechnology Research Group (MANRG)] said, however, that up until recently, the particles’ production had involved expensive chemical and physical processes that often used toxic materials with potential hazards such as environmental toxicity, cytotoxicity and carcinogenicity.
“Thanks to the Eucalyptus macrocarpa, we’re changing that. Our method is water-based, performed at room temperature and without the need for complex equipment and is clean and non-toxic,” he said.
The ‘green’ production of gold nanometre scale particles involves dissolving high purity gold wire into a mixture of nitric and hydrochloric acid to produce gold chloride.
The gold chloride is then mixed with a water-based solution of leaf extracts from the common Eucalyptus macrocarpa and allowed to synthesize at room temperature.
“Not only does this result in the creation of nanometre scale gold prisms, but the wax of the eucalypt leaf extract provides an additional antibacterial and antifungal quality,” Dr Poinern said.
“Since bacterial and fungal species have the ability to develop immunity against commonly used antibiotics over time, our gold nanometre scale particles also stand to be a new tool against antibiotic resistant forms of microorganisms.”
Dr Poinern said the nanometre scale gold particles were tested as antibacterial agents against both E. coli and B. subtilis, producing zone inhibition of 19mm and 16mm respectively.
Murdoch University has provided an image of eucalyptus leaves,
Eucalyptus macrocarpa is giving nano-medicine a boost
Here’s a link to and a citation for the published paper,
Green biosynthesis of gold nanometre scale plates using the leaf extracts from an indigenous Australian plant Eucalyptus macrocarpa by Gérrard Eddy Jai Poinern, Peter Chapman, Xuan Le, and Derek Fawcett. Gold Bulletin DOI: 10.1007/s13404-013-0096-7 Online ISSN 2190-7579
The paper is open access.
One final note, I trust the koala population is willing to share one of the mainstays of their diet.