Tag Archives: Guozhen Liu

CNBP at ‘Science meets Policymakers’

8 August 2017:

CNBP was well represented at the STA ‘Science meets Policymakers’ event held in Canberra, August 8, 2017.

Researchers A/Prof Guozhen Liu, Dr Alf Garcia-Bennett, Dr Sanam Mustafa and Dr Hannah Brown all attended and heard a number of talks on topics ranging from ‘A Whole Government approach to Science Policy’, to ‘A Crash-course in STEM and Policy Making’ through to discussion on ‘Positive and Meaningful Contributions to Policy.’

A/Prof Guozhen Liu particularly enjoyed the ‘Working Round Table’ discussion. “We discussed the 2030 Strategic Plan for the Australian Innovation, Science and Research System, which will help shape future science activity in Australia. It was emphasized that Australia encourages both fundamental and applied research, and that research excellence is key.”

A/Prof Liu also noted the importance of effective communication between stakeholders. “Methods and approaches to drive effective and engaged connections between Universities, Government and Industry were topics that were explored and discussed in depth throughout the day.”

The ‘Science meets Policymakers’ event brought together researchers and practitioners from a range of science and technology disciplines, with policymakers from across government departments and agencies. Objectives included to make connections and to examine the intersection between the evidence base and actual policy development.

Nanotechnology meets bioengineering

29 June 2017:

The Fudan-UH-MQ Workshop on ‘Nanotechnology meets Bioengineering’ was well supported by CNBP researchers at Macquarie University,  Wed 28th June – Thu 29th June.

A joint workshop, organised within the framework of University wide trilateral collaboration between Fudan, Hamburg and Macquarie, the event aimed to enhance collaborations between all three universities as well as generate potential cotutelle PhD candidates.

CNBP researchers presenting at the workshop included:

Prof. Nicolle H. Packer (CNBP Chief Investigator, pictured)
Cellular glycosylation: opportunities for discovering new molecular targets.

A/Prof. Anwar Sunna (CNBP Associate Investigator)
A platform technology for the self assembly of functional materials.

A/Prof. Guozhen Liu (CNBP Associate Investigator)
Nanotools for in vivo cytokine monitoring in neuroscience.

Dr. Nicole Cordina (CNBP Research Fellow)
Functionalisation of fluorescent nanodiamonds for bio-imaging applications.

Below: Prof. Nicolle Packer presents her talk on glycans.

China visit by Centre researcher

16 May 2017:

On a recent trip to China, CNBP Research Fellow A/Prof Guozhen Liu undertook a number of visits and talks, discussing her advanced sensing, nano-particle and bio-imaging work. This included:

5 May-8 May: Attendance at the International Congress on Analytical Sciences 2017 (ICAS2017) at Kaikou, China. Here Guozhen gave an oral presentation with the title “Engineering reduced graphen oxides towards a label-free electrochemical immunosensor for detection of tumor necrosis factor-alpha.”

11 May: Guozhen gave an invited talk titled, “Nanotools for cytokine monitoring in neuroscience” at Prof Zhihong Zhang’s research team at Huazhong University of Science and Technology, Wuhan. Prof Zhang is one of CNBP’s Partner Investigators at HUST.

13-14 May: Guozhen provided a keynote speech, titled, “An optical fibre based ex-vivo device for detection of cytokines” at the 2nd International Congress on Biomedical Imaging and Signal Processing (ICBISP 2017) at Wuhan.

Below: A/Prof Guozhen Liu (right) visiting CNBP Partner Investigator Prof Zhihong Zhang.

 

Maximizing particle concentration

28 April 2017:

A new paper from CNBP researchers reports on an improvement to deterministic lateral displacement arrays, which allows for higher particle concentration enhancement. The work has just been published in the journal ‘Biomicrofluidics’ and is accessible online.

Journal: Biomicrofluidics.

Title: Maximizing particle concentration in deterministic lateral displacement arrays.

Authors: Shilun Feng, Alison M. Skelley, Ayad G. Anwer (pictured top left), Guozhen Liu and David W. Inglis.

Abstract: We present an improvement to deterministic lateral displacement arrays, which allows higher particle concentration enhancement. We correct and extend previous equations to a mirror-symmetric boundary. This approach allows particles to be concentrated into a central channel, no wider than the surrounding gaps, thereby maximizing the particle enrichment. The resulting flow patterns were, for the first time, experimentally measured. The performance of the device with hard micro-spheres and cells was investigated. The observed flow patterns show important differences from our model and from an ideal pattern. The 18 μm gap device showed 11-fold enrichment of 7 μm particles and nearly perfect enrichment—of more than 50-fold—for 10 μm particles and Jurkat cells. This work shows a clear path to achieve higher-than-ever particle concentration enhancement in a deterministic microfluidic separation system.

 

Nanoscale sensor detects disease

28 March 2017:

A new nanoscale sensor has been developed by CNBP researchers that can help detect cytokines — molecules that play a critical role in cellular response to infection, inflammation, trauma and disease.

Leader of the project A/Prof Guozhen Liu (pictured) said the release of certain cytokines by the body is frequently symptomatic of a disease or health-related issue. “Monitoring cytokine secretions at the cellular and subcellular level has enormous value in our understanding of basic physiology and how the body is actually working.”

The research featured in the online publication Photonics.com.

Nanoscale sensor to spot disease

28 March 2017:

A new nanoscale sensor has been developed that can help detect cytokines – molecules that play a critical role in cellular response to infection, inflammation, trauma and disease.

Reported in the science journal ‘Nanoscale’, the sensor consists of a modified graphene quantum dot (or GQD) which has been designed by researchers at the ARC Centre of Excellence for Nanoscale BioPhotonics (CNBP). It allows ultra-small amounts of cytokines to be identified in and around cells, with the work potentially opening up an exciting new avenue of biomedical research.

“Cytokines are molecules secreted by the cells of the immune system,” explains lead CNBP project scientist Guozhen Liu, Associate Professor at Macquarie University.

“The release of certain cytokines by the body is frequently symptomatic of a disease or health related issue, such as arthritis, inflammatory disorder or even cancer. Consequently, monitoring cytokine secretions at the cellular and sub-cellular level, has enormous value in our understanding of basic physiology and how the body is actually working.”

Traditionally, cytokine molecules have been extremely hard to measure and quantify.

“This has been due to their small size and their dynamic and transient nature,” says A/Prof Liu.

“What we’ve been able to do is to design and make a sensor that is so small that it can easily penetrate inside cells. Moreover, unlike other sensors it only responds when the cytokine is present. To this aim we have connected GQDs to cytokine sensing DNA molecules known as aptamers.”

Professor at Macquarie University, Ewa Goldys, Deputy Director at the Centre for Nanoscale BioPhotonics, also on the project team, noted that the detection of cytokines in body fluids, cells, tissues and organisms was attracting considerable attention in the biomedical research field. “Being able to track cytokine levels in real time opens new ways to monitor body physiology. This will ultimately lead to new diagnostic tools and new ways of treatment monitoring.”

Goldys believes that the innovative GQD sensing technology developed by the CNBP has potential widespread applications, due to the universal nature of the sensor design.

“We see these graphene quantum dot sensors as being excellent candidates for many other biomedical applications such as DNA and protein analysis, intracellular tracking as well as for monitoring of other cell secreted products in the body.”

Although still some years away from clinical study Goldys and Liu are both excited by the research. “Operating at the nanoscale we’re creating entirely new windows into the body and will gain valuable insights into the body, health, wellbeing and disease,” concludes Goldys.

RESEARCH PAPER:
http://pubs.rsc.org/en/content/articlelanding/2017/nr/c6nr09381g#!divAbstract

Below: CNBP Researcher A/Prof Guozhen Liu. Click on the image to access image download.

Investigating cell metabolism

Aziz Rehman1 March 2017:

A new publication from CNBP researchers (lead author Aziz Ul Rehman pictured) reports on the application of hyperspectral imaging in combination with fluorescence spectroscopy and chemical quenching to provide a new methodology to investigate cell metabolism.

The work has just been reported in the journal ‘Biomedical Optics Express’ and is accessible online.

Journal: Biomedical Optics Express.

Title: Fluorescence quenching of free and bound NADH in HeLa cells determined by hyperspectral imaging and unmixing of cell autofluorescence.

Authors: Aziz Ul Rehman, Ayad G. Anwer, Martin E. Gosnell, Saabah B. Mahbub, Guozhen Liu, and Ewa M. Goldys.

Abstract: Carbonyl cyanide-p-trifluoro methoxyphenylhydrazone (FCCP) is a well-known mitochondrial uncoupling agent. We examined FCCP-induced fluorescence quenching of reduced nicotinamide adenine dinucleotide / nicotinamide adenine dinucleotide phosphate (NAD(P)H) in solution and in cultured HeLa cells in a wide range of FCCP concentrations from 50 to 1000µM. A non-invasive label-free method of hyperspectral imaging of cell autofluorescence combined with unsupervised unmixing was used to separately isolate the emissions of free and bound NAD(P)H from cell autofluorescence. Hyperspectral image analysis of FCCP-treated HeLa cells confirms that this agent selectively quenches fluorescence of free and bound NAD(P)H in a broad range of concentrations. This is confirmed by the measurements of average NAD/NADH and NADP/NADPH content in cells. FCCP quenching of free NAD(P)H in cells and in solution is found to be similar, but quenching of bound NAD(P)H in cells is attenuated compared to solution quenching possibly due to a contribution from the metabolic and/or antioxidant response in cells. Chemical quenching of NAD(P)H fluorescence by FCCP validates the results of unsupervised unmixing of cell autofluorescence.

Hyperspectral unmixing methodology validated

Aziz Rehman10 February 2017:

A new publication from CNBP researchers Aziz Ul Rehman (pictured), Ayad Anwer, Martin Gosnell, Saabah Mahbub, Guozhen Liu and Ewa Goldys demonstrates the validation of an innovative hyperspectral unmixing methodology, that can derive chemical information from cell colour.

The work has just been reported in the journal ‘Biomedical Optics Express’ and is accessible online.

Journal: Biomedical Optics Express.

Title: Fluorescence quenching of free and bound NADH in HeLa cells determined by hyperspectral imaging and unmixing of cell autofluorescence.

Authors: Aziz Ul Rehman, Ayad G. Anwer, Martin E. Gosnell, Saabah B. Mahbub, Guozhen Liu, and Ewa M. Goldys.

Abstract: Carbonyl cyanide-p-trifluoro methoxyphenylhydrazone (FCCP) is a well-known mitochondrial uncoupling agent. We examined FCCP-induced fluorescence quenching of reduced nicotinamide adenine dinucleotide / nicotinamide adenine dinucleotide phosphate (NAD(P)H) in solution and in cultured HeLa cells in a wide range of FCCP concentrations from 50 to 1000µM. A non-invasive label-free method of hyperspectral imaging of cell autofluorescence combined with unsupervised unmixing was used to separately isolate the emissions of free and bound NAD(P)H from cell autofluorescence. Hyperspectral image analysis of FCCP-treated HeLa cells confirms that this agent selectively quenches fluorescence of free and bound NAD(P)H in a broad range of concentrations. This is confirmed by the measurements of average NAD/NADH and NADP/NADPH content in cells. FCCP quenching of free NAD(P)H in cells and in solution is found to be similar, but quenching of bound NAD(P)H in cells is attenuated compared to solution quenching possibly due to a contribution from the metabolic and/or antioxidant response in cells. Chemical quenching of NAD(P)H fluorescence by FCCP validates the results of unsupervised unmixing of cell autofluorescence.

Centre researchers at Biosensor Symposium

guozhen_liu30 November 2016:

CNBP Research Fellows, Associate Professor Guozhen Liu (pictured), Dr Lindsay Parker and Dr Sabrina Heng have undertaken talks at the School of Biomedical Sciences at the University of Melbourne as part of a Biosensor Symposium, Wednesday 30th November, 2016.

Talks were as follows:

Guozhen Liu – Biophotonic Tools for Cytokine Sensing: From an on-cell surface ELISA to a spatial ELISA device.

Lindsay Parker – Biosensors and glycoproteins: linking nanoscience to neuroscience.

Sabrina Heng – Reversible Sensing with a Flip of the Switch.

The symposium shone a  spotlight on multidisciplinary research into developing, applying and using biosensors for biomedical sciences.

Developing novel nano-tools to better understand the brain

guozhen_liu11 November 2016:

Understanding how the brain works is one of the greatest challenges of modern science – A challenge that CNBP Research Fellow Guozhen Liu is certainly up to!

She has recently been awarded an ARC Future Fellowship commencing in 2017 and will work on the creation of a suite of novel biomolecular nano-formulations capable of adaptive responses to the rapidly evolving environment inside of the body.

Read the full ‘Research Impact’ story on the Macquarie University web site!

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