April/May 2009

Nanomatters is published quarterly by the ARCCFN and includes updates on projects, international activities and general Centre news. Nanomatters is also online and you can access an extensive archive dating back to December 2004.
For further information on our stories or Centre activities, please contact the Centre or email Paulette Baumgartl (p.baumgartl@uq.edu.au)

In this issue:

• Funding boost for Lightanate
• Project spotlight - silver nanoparticles
• Project spotlight - LDH research
• Publication highlights
• International activities
• General news

Research news

Centre start-up company receives major funding boost

Lightanate Pty Ltd continues to be a commercialisation success for the Centre. The UniQuest start-up company has received a major financial boost to commercialise its titanium dioxide technologies.
Uniseed, which supports the commercialisation of university research, has joined Cleantech Ventures Pty Ltd, a specialist water, energy and environmental investor based in Melbourne, in providing financial support to the new company.

Lightanate’s technologies aim to address global environmental and energy challenges. In the fields of low-cost solar cells and water treatment, Lightanate is developing innovations that have a higher energy efficiency and are less reliant on hazardous chemicals. The capital from Uniseed and Cleantech will focus on developing and demonstrating a revolutionary platform of titanium dioxide-based technologies, including Titanate - a photocatalyst which is highly active in visible light and Single Crystal - a highly reactive titanium oxide for low-cost solar energy applications.

The Centre researchers, led by director Professor Max Lu, will further develop Lightanate’s recyclable, potentially renewable, non-toxic and versatile materials platform, which enables harvesting of both visible and ultraviolet light for solar energy and water purification applications.
UniQuest’s Managing Director, David Henderson, said the investment will give Lightanate a significant push towards becoming a major player in the cleantech economy. “This funding will support Lightanate reaching several key development milestones along a strategic pathway for translating the technology into real outcomes for industry and consumers,” Mr Henderson said.
The research behind these innovations has been published in high impact journals, including Nature (453: 7195,638-U4, 2008).
For further information on Lightanate Pty Ltd and its activities, contact Astute Nanotechnology manager Dr Fouad Haghseresht
(f.haghseresht@uniquest.com.au)

Project spotlight - silver nanoparticles research nature highlight

Silver nanoparticles research from Centre members at the University of New South Wales, led by Centre co-director Prof Rose Amal, has featured as a research highlight in Nature Nanotechnology, which summarises notable research published in nanotechnology. The original article appeared in the journal Small (Reversible Antimicrobial Photoswitching in Nanosilver, Small 5: 3, 2009, 341-344 Cindy Gunawan, Wey Yang Teoh, Christopher P. Marquis, Juniahani Lifia, Rose Amal)
The following extract is from the highlight in Nature Nanotechnology, published online: 30 January 2009 | doi:10.1038/nnano.2009.18.

Silver nanoparticles are known for their ability to kill a variety of bacteria and are used in wound dressings, textiles and various biomedical devices. Researchers at the University of New South Wales now report that it is possible to ‘tune’ the antimicrobial activity of nanosilver by simply irradiating it with light.
Rose Amal and co-workers dispersed nanosilver on a semiconducting titanium-dioxide support using conventional techniques, and tested its ability to kill E. coli bacteria.

Concentrations greater than 50 mg L-1 of the nanosilver/titanium-dioxide material completely suppressed the growth of the bacteria over 6 h. Materials that were pre-irradiated with ultraviolet A (UVA) radiation allowed the bacteria to grow, and with an 80 h pre-irradiation, up to 75% of the antimicrobial activity could be switched off. However, when the material was0 subsequently subjected to visible light at wavelengths greater than 450 nm for 8 h, the bacterial growth was again suppressed. Irradiation with UVA or visible light moves electrons between the silver deposits and the titanium support causing the nanosilver to undergo oxidation or reduction reactions, which determines the amount of silver ions (one of the causes of bacterial death) that are present.
This new finding may lead to other interesting applications, but it also highlights the importance of the oxidation states of silver towards its antimicrobial action.

Project spotlight - LDH research features as cover story

A research article by Centre researchers Gordon Xu and Max Lu featured as a cover story in the Journal of Controlled Release.
Over the past decade non-viral gene and drug delivery have been major topics of scientific interest, with many interdisciplinary research teams developing novel transfection agents (e.g., polymeric carriers, liposomes, inorganic carriers, and many more) and delivery methods (e.g., electroporation, microinjection) for both in vitro and in vivo applications.
However, while many transfection agents are able to efficiently deliver nucleic acids and/or drugs, it is often a random process.

In order to address specific organs in vivo or target certain intra-cellular organelles in vitro, many researchers attempt to use antibody coupling or similar techniques.
While this not only increases the cost, it also introduces additional complications, e.g., non-desirable inflammatory responses in vivo and will often result in a loss of efficiency.
Layered double hydroxide (LDH) nanoparticles have a lot of potential as effective non-viral agents for cellular drug and gene delivery due to their low cytotoxicity, good biocompatibility, and many other desirable properties.

The article, Subcellular compartment targeting of layered double hydroxide nanoparticles, Journal of Controlled Release 130 (2008) 86–94, describes how these nanoparticles can be prepared exhibiting different morphologies—rod-like and hexagonal—and their influences on cellular localisation.
The researchers found that rod-like LDH nanoparticles are concentrated within the nucleus of mammalian cells and their hexagonal counterparts mainly localise in the perinuclear cytoplasm.
This is the first time that different intra-cellular compartments have been targeted by a simple change in morphology of the carrier without the need for functionalisation of either the carrier or the payload.
The cellular uptake and release mechanisms of particles of both morphologies were further elucidated using uptake inhibiting drugs and dominant/negative mutants of the cell lines. They found that the uptake of these particles is mainly facilitated by clathrin-mediated, time- and concentration-dependent endocytosis, with the nuclear translocation of the rod-like nanoparticles probably being the result of a microtubule-mediated trafficking process.

Publication highlights

Top 5

Centre research published in 2008 became one of the top 5 most accessed papers in October 2008 in Advanced Functional Materials -
Zhang et al. Fabrication and Size-Selective Bioseparation of Magnetic Silica Nanospheres with Highly Ordered Periodic Mesostructure Adv. Funct. Mater. 2008, vol. 18, no. 20, pp. 3203–3212

Frontpiece Advanced Functional Materials
A paper by Centre student Richard Kydd and colleagues from the Centre's NSW node featured as a frontpiece in Advanced Functional Materials -
Kydd et al. Flame-Synthesized Copper Dimers: Flame-Synthesized Ceria-Supported Copper Dimers for Preferential Oxidation of CO. Adv. Funct. Mater. 3/2009

International activities

India trip
Centre researchers Drs Jorge Beltramini and Akshat Tanksale spent four weeks in India as part of their research collaboration with Professors P. Selvam and B. Viswanathan from the National Centre for Catalysis Research, IIT-Madras, Chennai.
During their visit Dr Beltramini attended and delivered an oral presentation at the International Conference on Hydrogen Production and Storage at the Institute of Science, Bangalore, and presented an invited lecture at the Indian Catalysis Society Symposium in Pune.
They also visited the National Catalysis Research Laboratories at the Indian Institute of Technology Chennai and met and discussed research progress on Carbohydrates conversion to Chemicals, a project funded by the Australia - India Strategic Research Fund.

German post-doctoral research Fellow
German post-doctoral research fellow Dr Roland Marschall from the Leibniz University Hanover is spending one year at the Centre at The University of Queensland. While here in Australia, Roland will work with Centre Senior Research Fellow Dr Lianzhou Wang. His research interests include photocatalytic water splitting using new doped layered perovskite materials, like titanates.

General news

ANU group moved to Deakin University
The ANU group led by Professor Ying Chen has moved from ANU to Deakin University to join the newly established Institute of Technology, Research and Innovation at the Geelong campus. Professor Chen has taken the position of Chair in Nanotechnology, recognition of his pioneering work and international reputation in nanomaterials and nanotechnology research. The group is world-leading in nanomaterials synthesis and commercialisation following their invention of the ball-milling and annealing method. At Deakin University, the group will continue the Centre’s research programs and will also conduct fundamental research in nanomaterials for new energy storage (solar cells, batteries and capacitors), environmental protection and medical applications under the substantial financial support and new equipment, including the Cyber scanning probe microscope and Solartron Celltest system, from Deakin University.

2008 Annual Report
Each year the Centre is required to summarise all research activities and expenditure in an annual report. The 2008 report was submitted to the ARC in March and is now available online
www.arccfn.org.au

New centre administrator
In January 2009 Ms Celestien Warnaar took over the role as Centre Administrator.
Celestien can be contacted on
t: (+61) 7 3346 3883
f: (+61) 7 3346 3973
e: c.warnaar@uq.edu.au

Annual conference
The Centre’s Annual Conference - Advances in Functional Nanomaterials - will be held in Coffs Harbour, NSW from the 9-11 November 2009.
Check the Centre’s website for updates.

Contacts