Tag Archives: Ewa Goldys

Ultrasensitive imaging of unique nanoruby probes

Wan Razali6 June 2016:

Our CNBP researchers describe a wide-field time-gated photoluminescence microscopy system, customised for ultrasensitive imaging of unique nanoruby probes in this latest paper published in the Journal of Biophotonics.

Publication Title: Wide-Field Time-Gated Photoluminescence Microscopy for Fast Ultrahigh-Sensitivity Imaging of Photoluminescent Probes.

Authors: Wan A W Razali (pictured top left), Varun K A Sreenivasan, Carlo Bradac, Mark Connor, Ewa M Goldys and Andrei V Zvyagin.

Abstract: Fluorescence microscopy is a fundamental technique for the life sciences, where biocompatible and photostable photoluminescence probes in combination with fast and sensitive imaging systems are continually transforming this field. A wide-field time-gated photoluminescence microscopy system customised for ultrasensitive imaging of unique nanoruby probes with long photoluminescence lifetime is described. The detection sensitivity derived from the long photoluminescence lifetime of the nanoruby makes it possible to discriminate signals from un-wanted autofluorescence background and laser backscatter by employing a time-gated image acquisition mode. This mode enabled several-fold improvement of the photoluminescence imaging contrast of discrete nanoru-
bies dispersed on a coverslip. It enabled recovery of the photoluminescence signal emanating from discrete na-norubies when covered by a layer of an organic fluorescent dye, which were otherwise invisible without the use of spectral filtering approaches. Time-gated imaging also facilitated high sensitivity detection of nanorubies in a biological environment of cultured cells. Finally, we monitor the binding kinetics of nanorubies to a functionalised substrate, which exemplified a real-time assay in biological fluids. 3D-pseudo colour images of nanorubies immersed in a highly fluorescent dye solution. Nanoruby photolumines-cence is subdued by that of the dye in continuous  excitation/imaging (left), however it can be recovered by time-gated imaging (right). At the bottom is schematic diagram of nanoruby assay in a biological fluid.

The paper is available online.


Minnesota students visit MQ node

Ewa Goldys Low Res Edit 015920 May 2016:

On Friday May 20th 2016, a group of 25 engineering and physics students from the University of Minnesota visited Macquarie University for a very full day of talks, seminars and laboratory tours.

As a part of this visit, CNBP Deputy Director Prof Ewa Goldys provided a 45 minute talk to the students, providing an overview of the Centre and its key research activities.

The future use of nanoparticles, to aid in healthcare and diagnostic capability provoked widespread interest and discussion in the group as they saw the potential benefits of the still evolving technology.

Below: Ewa Goldys explaining the use of nano-rubies and nano-crystals in CNBP related research.



Combining computer analysis with microscopy


CNBP researchers have successfully combined computer analysis with microscopy, to extract highly detailed cellular information that will help distinguish between healthy and diseased cells, in areas as diverse as cancer, injury and inflammation.

The approach, reported in the journal ‘Scientific Reports’, has shown that subtle biochemical signatures of cells can be captured and then categorized, to an extent that has never been seen before.

Paper Title: Quantitative non-invasive cell characterisation and discrimination based on multispectral autofluorescence features.

Authors: Martin E. Gosnell, Ayad G. Anwer, Saabah B. Mahbub, Sandeep Menon Perinchery, David W. Inglis, Partho P. Adhikary, Jalal A. Jazayeri, Michael A. Cahill, Sonia Saad, Carol A. Pollock, Melanie L. Sutton-McDowall, Jeremy G. Thompson & Ewa M. Goldys.

Abstract: Automated and unbiased methods of non-invasive cell monitoring able to deal with complex biological heterogeneity are fundamentally important for biology and medicine. Label-free cell imaging provides information about endogenous autofluorescent metabolites, enzymes and cofactors in cells. However extracting high content information from autofluorescence imaging has been hitherto impossible. Here, we quantitatively characterise cell populations in different tissue types, live or fixed, by using novel image processing and a simple multispectral upgrade of a wide-field fluorescence microscope. Our optimal discrimination approach enables statistical hypothesis testing and intuitive visualisations where previously undetectable differences become clearly apparent. Label-free classifications are validated by the analysis of Classification Determinant (CD) antigen expression. The versatility of our method is illustrated by detecting genetic mutations in cancer, non-invasive monitoring of CD90 expression, label-free tracking of stem cell differentiation, identifying stem cell subpopulations with varying functional characteristics, tissue diagnostics in diabetes, and assessing the condition of preimplantation embryos.

The research paper is accessible online. A CNBP media release is also available.


Review paper published in Nanoscale

Annemarie Nadort26 February 2016:

Dr Annemarie Nadort and CNBP researchers Jiangbo Zhao and Ewa Goldys  have had a review paper accepted for the high-impact journal Nanoscale.

Title: Lanthanide upconversion luminescence at a nanoscale: fundamentals and optical properties

Authors: Annemarie Nadort, Jiangbo Zhao and  Ewa M. Goldys.

Abstract: Upconversion photoluminescence is a nonlinear effect where multiple lower energy excitation photons produce higher energy emission photons. This fundamentally interesting process has many applications in biomedical imaging, light source and display technology, and solar energy harvesting. In this review we discuss the underlying physical principles and their modelling using rate equations. We discuss how the understanding of photophysical processes enabled strategic influence over the optical properties of upconversion especially in rationally designed materials. We subsequently present an overview of recent experimental strategies to control and optimize the optical properties of upconversion nanoparticles, focussing on their emission spectral properties and brightness.

The paper is available online.

Invited talks at University of Colorado Boulder

Ewa Goldys Low Res Edit 015911 February 2016:

Ewa Goldys, CNBP Deputy Director and Lindsay Parker, CNBP Research Fellow were invited speakers at the University of Colorado Boulder.

Ewa and Lindsay, hosted by Profs Steven Meier and Linda Watkins from the Department of Psychology & Neuroscience, spoke about various activities and projects currently taking place across the CNBP. Also discussed were potential areas of research collaboration.

Coverage: Counting cancer-busting oxygen molecules

Ewa Goldys Low Res Edit 01595 February, 2016:

Researchers from the Centre for Nanoscale BioPhotonics (CNBP), have shown that nanoparticles used in combination with X-rays, are a viable method for killing cancer cells deep within the living body.

The research, published in the journal ‘Scientific Reports‘ is based on the successful quantification of singlet oxygen produced during photodynamic therapy for cancer. Singlet oxygen molecules (a highly reactive form of oxygen) are able to kill or inhibit growth of cancer cells in the body due to their toxicity.

Co-lead author on the paper, CNBP Deputy Director Ewa Goldys, provided comment on the work and was featured in a number of media publications including PHYS.ORGGIZMAG and R&D Magazine (all of which are accessible online).


Counting cancer-busting oxygen molecules

Ewa Goldys Low Res Edit 015928 January 2016:

CNBP researchers have established that a therapeutic dose of X-rays, in combination with CeF3 nanoparticles, can produce enough singlet oxygen molecules to be effective in photodynamic therapy. The finding has been reported in the journal Scientific Reports, published online today.

The complete research paper is available for download, from the Nature Publishing Group web site. A CNBP media release has also been produced.

Cytokine detection based on immunosensing

guozhen_liu8 January 2016:

CNBP researchers Guozhen Liu, Mark Hutchinson and Ewa Goldys are all authors on a recent review paper examining the detection of cytokines  based on immunosensing. The paper was published in the journal Biosensors and Bioelectronics.

Paper Title:  “Recent advances in cytokine detection by immunosensing.”

Abstract: The detection of cytokines in body fluids, cells, tissues and organisms continues to attract considerable attention due to the importance of these key cell signaling molecules in biology and medicine. In this review, we describe recent advances in cytokine detection in the course of ongoing pursuit of new analytical approaches for these trace analytes with specific focus on immunosensing.

We discuss recent elegant designs of sensing interface with improved performance with respect to sensitivity, selectivity, stability, simplicity, and the absence of sample matrix effects. Various immunosensing approaches based on multifunctional nanomaterials open novel opportunities for ultrasensitive detection of cytokines in body fluids in vitro and in vivo.

Methodologies such as suspension arrays also known as bead assays together with optical fiber-based sensors, on their own or in combination with microfluidic devices will continue to have an important role to address the grand challenge of real-time in vivo multiplex cytokine detection.

The paper is available online.


Coverage: MQ and Regeneus agreement

Ewa Goldys Low Res Edit 015924 November 2015:

Professor Ewa Goldys, Deputy Director from the Centre for Nanoscale BioPhotonics was interviewed by The Australian and CH 10 News regarding a new collaboration agreement
between Macquarie University and regenerative medicine company Regeneus. The agreement is based on further developing and commercialising CNBP cell selection technology.