Monthly Archives: September 2016

Sensing sound with light

Ivan Maksymov Low Res Edit 01479 September 2016:

New research from CNBP  researcher Ivan Maksymov and CNBP CI Andrew Greentree outlines a new way to detect ultrasound in the body.

The researchers showed that a plasmonic nanoantenna – like a television antenna, but 1000 times smaller than the width of a human hair – can be used to sense ultrasound in the body.

“The biggest problem with sensing ultrasound is the size of the receiver” explains Dr Maksymov. “By using metal nanoparticles, we have shown that we can shrink the size of the hydrophone.” Smaller detectors mean that ultrasound can be probed in smaller areas of the body. “The key is to look inside the smallest blood vessels.”

Solving the work was challenging as the device operates in the so-called deep subwavelength regime – where the size of the device is much smaller than the wavelength of both the light and the sound.

The research appeared in the journal Scientific Reports on the 9th of September, 2016.

Journal: Scientific Reports.

Publication title: Plasmonic nanoantenna hydrophones.

Authors: Ivan S. Maksymov & Andrew D. Greentree.

Abstract: Ultrasound is a valuable biomedical imaging modality and diagnostic tool. Here we theoretically demonstrate that a single dipole plasmonic nanoantenna can be used as an optical hydrophone for MHz-range ultrasound. The nanoantenna is tuned to operate on a high-order plasmon mode, which provides an increased sensitivity to ultrasound in contrast to the usual approach of using the fundamental dipolar plasmon resonance. Plasmonic nanoantenna hydrophones may be useful for ultrasonic imaging of biological cells, cancer tissues or small blood vessels, as well as for Brillouin spectroscopy at the nanoscale.

The paper is available online.

State Government Minister visits CNBP

mark-and-minister8 September 2016:

CNBP was delighted today to have hosted a visit from SA State Government Minister Martin Hamilton-Smith MP, Minister for Investment and Trade, Small Business, Defence Industries and Veteran’s Affairs.

During the visit, the Minister was provided an overview of CNBP biophotonic activity by Director Prof Mark Hutchinson and was taken on a tour of the CNBP laboratories at the University of Adelaide to see CNBP science in action.

In coming weeks, Prof Hutchinson will be accompanying the Minister on a delegation visit to Tokyo hosted by Health Industries SA and will be visiting the Australian Embassy in Tokyo and industry interests in Japan as well.

Hamilton-Smith noted that he was extremely interested in CNBP’s work, particularly in the food industry space in relation to premium quality sensing techniques.

New CNBP laboratory opened at Macquarie University

OLYMPUS DIGITAL CAMERA6 September 2016:

CNBP’s new ‘Biomolecular Discovery Laboratory’, along with two other new laboratories at Macquarie University (a redeveloped Synthetic Biology Lab and new research facilities for Organometallics), were officially opened today by Professor Mary O’Kane, NSW Chief Scientist and Engineer.

The opening event, hosted by Macquarie University’s Deputy Vice-Chancellor (Research), Professor Sakkie Pretorius saw a number of VIP guests in attendance including CNBP Director, Prof Mark Hutchinson.

Hutchinson who spoke at the official opening noted the close collaboration between Macquarie University and the CNBP and explained how the relationship between the two organisations exemplified and gave real meaning to the Centre’s four key belief principles of Academic Excellence, Commercial Impact, Quality Communication and a Nurturing Environment.

The new CNBP laboratory space at Macquarie University will host twenty-four CNBP researchers and will support the development of new biomolecular probes and methodology, the functionalisation of nanoparticles, as well as the investigation of nanoparticle mechanisms and drug delivery.

Additionally, it will facilitate interactions between CNBP chemists, mass spectrometrists, biochemists, physicists and biologists in a large single area, aiding CNBP interdisciplinary research in the development of its new light based sensing tools that operate at the nanoscale.

Below – Professor Mary O’Kane, NSW Chief Scientist and Engineer cuts a ribbon to formally open the laboratory spaces while guests look on.

OLYMPUS DIGITAL CAMERA

Emission stability and reversibility of upconversion nanocrystals

deming-liu_crop5 September 2016:

A new paper by CNBP researchers (Deming Liu lead author pictured left) has demonstrated that oleic acid and oleylamine as co-surfactants with a right balance can be used to synthesize homogeneous core-shell NaYF4 nanocrystals. A key finding reported is that coating upconversion nanocrystals (UCNPs) with the inert shells, improved the luminescent emission stability and reversibility of UCNPs against quenching caused by increased temperature or decreased pH.

Journal: Journal of Materials Chemistry C

Publication title: Emission Stability and Reversibility of Upconversion Nanocrystals.

Authors: Deming Liu , Xiaoxue Xu , Fan Wang , Jiajia Zhou , Chao Mi , Yiqing Lu , Chenshuo Ma , Lixin Zhang , Ewa M. Goldys , Jun Lin and Dayong Jin.

Abstract: Rare-earth doped upconversion nanocrystals have emerged as a novel class of luminescent probes for biomedical applications. The knowledge about their optical stability in aqueous solution at different pH and temperature condit ions has not been comprehensively explored. Here we conduct a systematic investigation and report the emission stability and reversibility of the typical NaYF4: Yb3+,Er3+ nanocrystals and their core-shell nanostructures in aqueous solution at different temperatures and with different pH values. These nanocrystals show reversible luminescence response to temperature changes, while low pH permanently quenches their luminescence. With the addition of inert shells, with thickness ranging from 1.5 nm to 8 nm, the emission stability and reversibility change significantly. Thicker inert shells not only lead to significant enhancement in the emission intensity but also stabilize its optical responses which becomes less affected by temperature variations and pH conditions. This study suggests that upconversion nanocrystal-based sensitive temperature and pH sensors do not generally benefit from the core-shell structure usually recommended for enhanced upconversion luminescence.

The paper is available online.

 

Detection of prostate cancer cells

Nima Sayyadi_web5 September 2016:

The latest paper published by CNBP researchers (lead author Nima Sayyadi, pictured left), reports on a bright red water soluble luminescent molecular probe that was successfully synthesized, with multiple platforms developed for sensitive immunodetection of prostate cancer cells. The probe has immediate potential for sensitive detection of a wide range of proteins and disease-specific cellular antigens.

Journal: Analytical Chemistry.

Publication title: Sensitive time-gated immunoluminescence detection of prostate cancer cells using a TEGylated europium ligand.

Authors: Nima Sayyadi, Irene Justiniano, Russell Edwin Connally, Run Zhang, Bingyang Shi, Liisa Kautto, Arun V Everest-Dass, Jingli Yuan, Bradley John Walsh, Dayong Jin, Robert Drant Willows, James A. Piper, and Nicolle H. Packer.

Abstract: We describe the application of a synthetically developed tetradentate β-diketonate-europium chelate with high quan-tum yield (39%), for sensitive immunodetection of prostate cancer cells (DU145). MIL38 antibody, a mouse monoclonal antibody against Glypican 1, conjugated directly to the chelate via lysine residues, resulted in soluble (hydrophilic) and stable immunoconjugates. Indirect labeling of the antibody by a europium chelated secondary polyclonal antibody and a streptavidin/biotin pair was also performed. All of these bright luminescent conjugates were used to stain DU145 cells, a prostate cancer cell line, using time gated luminescence microscopy for imaging, and their performances were compared to conventional FITC labelling. For all prepared conjugates, the europium chelate in conjunction with a gat-ed auto-synchronous luminescence detector (GALD) completely suppressed the cellular autofluorescence background to allow capture of vivid, high contrast images of immune-stained cancer cells.

The paper is available online.

Welcome Akash Bachhuka

OLYMPUS DIGITAL CAMERA2 September 2016:

CNBP would like to welcome Akash Bachhuka, Research Fellow, to the Centre for Nanoscale BioPhotonics for a six-month period.

Akash who has just finished his PhD a few months ago at the University of South Australia, will join CNBP Investigator Prof Heike Ebendorff-Heidepriem’s team at the University of Adelaide.

During his time with CNBP, Akash will work with Centre researchers Roman Kostecki and Sabrina Heng on surface functionalisation.

Welcome aboard Akash!