Tag Archives: PeerRev

Strong microwave photon-magnon coupling in multiresonant dielectric antennas

9 October 2018:

A new perspectives paper by CNBP researcher Dr Ivan Maksymov, RMIT University discusses dielectric resonant systems and demonstrates their ability to operate as multiresonant antennas for light, microwaves, magnons, sound, vibrations and heat.

Journal: Journal of Applied Physics.

Publication title: Perspective: Strong microwave photon-magnon coupling in multiresonant dielectric antennas.

Author: Ivan S. Maksymov.

Abstract: Achieving quantum-level control over electromagnetic waves, magnetisation dynamics, vibrations, and heat is invaluable for many practical applications and possible by exploiting the strong radiation-matter coupling. Most of the modern strong microwave photon-magnon coupling developments rely on the integration of metal-based microwave resonators with a magnetic material. However, it has recently been realised that all-dielectric resonators made of or containing magneto-insulating materials can operate as a standalone strongly coupled system characterised by low dissipation losses and strong local microwave field enhancement. Here, after a brief overview of recent developments in the field, I discuss examples of such dielectric resonant systems and demonstrate their ability to operate as multiresonant antennas for light, microwaves, magnons, sound, vibrations, and heat. This multiphysics behavior opens up novel opportunities for the realisation of multiresonant coupling such as, for example, photon-magnon-phonon coupling. I also propose several novel systems in which strong photon-magnon coupling in dielectric antennas and similar structures is expected to extend the capability of existing devices or may provide an entirely new functionality. Examples of such systems include novel magnetofluidic devices, high-power microwave power generators, and hybrid devices exploiting the unique properties of electrical solitons.

Nanoporous anodic alumina photonic crystals

4 October 2018:

A new review paper by CNBP student Cheryl Suwen Law (University of Adelaide) & other CNBP coauthors provides a comprehensive and up-to-date collation of fundamental and applied developments of nanoporous anodic alumina photonic crystals as optical platforms for chemo- and biosensing applications.

Journal: Nanomaterials.

Publication title: Nanoporous Anodic Alumina Photonic Crystals for Optical Chemo- and Biosensing: Fundamentals, Advances, and Perspectives.

Authors: Cheryl Suwen Law, Siew Yee Lim, Andrew D. Abell, Nicolas H. Voelcker and Abel Santos.

Abstract: Optical sensors are a class of devices that enable the identification and/or quantification of analyte molecules across multiple fields and disciplines such as environmental protection, medical diagnosis, security, food technology, biotechnology, and animal welfare. Nanoporous photonic crystal (PC) structures provide excellent platforms to develop such systems for a plethora of applications since these engineered materials enable precise and versatile control of light–matter interactions at the nanoscale. Nanoporous PCs provide both high sensitivity to monitor in real-time molecular binding events and a nanoporous matrix for selective immobilization of molecules of interest over increased surface areas. Nanoporous anodic alumina (NAA), a nanomaterial long envisaged as a PC, is an outstanding platform material to develop optical sensing systems in combination with multiple photonic technologies. Nanoporous anodic alumina photonic crystals (NAA-PCs) provide a versatile nanoporous structure that can be engineered in a multidimensional fashion to create unique PC sensing platforms such as Fabry–Pérot interferometers, distributed Bragg reflectors, gradient-index filters, optical microcavities, and others. The effective medium of NAA-PCs undergoes changes upon interactions with analyte molecules. These changes modify the NAA-PCs’ spectral fingerprints, which can be readily quantified to develop different sensing systems. This review introduces the fundamental development of NAA-PCs, compiling the most significant advances in the use of these optical materials for chemo- and biosensing applications, with a final prospective outlook about this exciting and dynamic field.

3D printing of OCT probes

4 October 2018:

A new paper published in Scientific Reports demonstrates the feasibility of 3D printing of optical coherence tomography (OCT) fibre-optic probes. Lead author on the publication is CNBP’s Dr Jiawen Li (pictured).

Journal: Scientific Reports.

Publication title: Two-photon polymerisation 3D printed freeform micro-optics for optical coherence tomography fibre probes.

Authors: Jiawen Li, Peter Fejes, Dirk Lorenser, Bryden C. Quirk, Peter B. Noble, Rodney W. Kirk, Antony Orth, Fiona M. Wood, Brant C. Gibson, David D. Sampson & Robert A. McLaughlin.

Abstract: Miniaturised optical coherence tomography (OCT) fibre-optic probes have enabled high-resolution cross-sectional imaging deep within the body. However, existing OCT fibre-optic probe fabrication methods cannot generate miniaturised freeform optics, which limits our ability to fabricate probes with both complex optical function and dimensions comparable to the optical fibre diameter. Recently, major advances in two-photon direct laser writing have enabled 3D printing of arbitrary three-dimensional micro/nanostructures with a surface roughness acceptable for optical applications. Here, we demonstrate the feasibility of 3D printing of OCT probes. We evaluate the capability of this method based on a series of characterisation experiments. We report fabrication of a micro-optic containing an off-axis paraboloidal total internal reflecting surface, its integration as part of a common-path OCT probe, and demonstrate proof-of-principle imaging of biological samples.

Amperometric sensing device to detect cytokines

10 September 2018:

A new paper with CNBP co-authors Prof Mark Hutchinson, Prof Ewa Goldys and Dr Guozhen Liu demonstrates an amperometric sensing device based on graphene oxide (GO) and structure-switching aptamers for long-term detection of cytokines in a living organism.

Journal: ACS Applied Materials and Interfaces.

Publication title: Graphene Oxide Based Recyclable in Vivo Device for Amperometric Monitoring of Interferon-γ in Inflammatory Mice.

Authors: Chaomin Cao, Ronghua Jin, Hui Wei, Wenchao Yang, Ewa M. Goldys, Mark R. Hutchinson, Shiyu Liu, Xin Chen, Guangfu Yang, and Guozhen Liu.

Abstract: Cytokine sensing is challenging due to their typically low abundances in physiological conditions. Nanomaterial fabricated interfaces demonstrated unique advantages in ultrasensitive sensing. Here, we demonstrate an amperometric sensing device based on graphene oxide (GO) and structure-switching aptamers for long-term detection of cytokines in a living organism. The device incorporates a single layer of GO acting as a signal amplifier on glassy carbon electrodes. The hairpin aptamers specific to interferon-γ (IFN-γ), which were loaded with redox probes, are covalently attached to GO to serve as biorecognition moieties. IFN-γ was able to trigger the configuration change of aptamers while releasing the trapped redox probes to introduce the electrochemical signal. This in vivo device was capable of quantitatively and dynamically detecting IFN-γ down to 1.3 pg mL–1 secreted by immune cells in cell culture medium with no baseline drift even at a high concentration of other nonspecific proteins. The biocompatible devices were also implanted into subcutaneous tissue of enteritis mice, where they performed precise detection of IFN-γ over 48 h without using physical barriers or active drift correction algorithms. Moreover, the device could be reused even after multiple rounds of regeneration of the sensing interface.

Optical fibre innovation via trans-disciplinary approach!

10 September 2018:

CNBP researchers have published a new  trans-disciplinary review that reports on the Centre’s development of advanced optical fibre probes for use in biomedical sensing and imaging. The paper examines CNBP innovation through convergence of multiple science disciplines to generate opportunities for the fibre probes to address key challenges in real-time in vivo diagnostics. The lead author on the paper is Dr Jiawen Li (pictured).

Journal: APL Photonics.

Publication title: Perspective: Biomedical sensing and imaging with optical fibers—Innovation through convergence of science disciplines.

Authors: Jiawen Li, Heike Ebendorff-Heidepriem, Brant C. Gibson,  Andrew D. Greentree, Mark R. Hutchinson, Peipei Jia, Roman Kostecki, Guozhen Liu, Antony Orth, Martin Ploschner, Erik P. Schartner,   Stephen C. Warren-Smith, Kaixin Zhang, Georgios Tsiminis, and Ewa M. Goldys.

Abstract: The probing of physiological processes in living organisms is a grand challenge that requires bespoke analytical tools. Optical fiber probes offer a minimally invasive approach to report physiological signals from specific locations inside the body. This perspective article discusses a wide range of such fiber probes developed at the Australian Research Council Centre of Excellence for Nanoscale BioPhotonics. Our fiber platforms use a range of sensing modalities, including embedded nanodiamonds for magnetometry, interferometric fiber cavities for refractive index sensing, and tailored metal coatings for surface plasmon resonance sensing. Other fiber probes exploit molecularly sensitive Raman scattering or fluorescence where optical fibers have been combined with chemical and immunosensors. Fiber imaging probes based on interferometry and computational imaging are also discussed as emerging in vivo diagnostic devices. We provide examples to illustrate how the convergence of multiple scientific disciplines generates opportunities for the fiber probes to address key challenges in real-time in vivo diagnostics. These future fiber probes will enable the asking and answering of scientific questions that were never possible before.

Peptides as bio-inspired electronic materials

7 September 2018:

A new paper with CNBP authors Jingxian Yu, John Horsley and Andrew Abell extends fundamental knowledge of charge transfer dynamics and kinetics in peptides and also open up new avenues to design and develop functional bio-inspired electronic devices, such as on/off switches and quantum interferometers, for practical applications in molecular electronics.

Journal: Accounts of Chemical Research.

Publication title: Peptides as Bio-Inspired Electronic Materials: An Electrochemical and First-Principles Perspective.

Authors: Jingxian Yu, John R. Horsley, and Andrew D. Abell.

Abstract: Molecular electronics is at the forefront of interdisciplinary research, offering a significant extension of the capabilities of conventional silicon-based technology as well as providing a possible stand-alone alternative. Bio-inspired molecular electronics is a particularly intriguing paradigm, as charge transfer in proteins/peptides, for example, plays a critical role in the energy storage and conversion processes for all living organisms. However, the structure and conformation of even the simplest protein is extremely complex, and therefore, synthetic model peptides comprising well-defined geometry and predetermined functionality are ideal platforms to mimic nature for the elucidation of fundamental biological processes while also enhancing the design and development of single-peptide electronic components.

In this Account, we first present intramolecular electron transfer within two synthetic peptides, one with a well-defined helical conformation and the other with a random geometry, using electrochemical techniques and computational simulations. This study reveals two definitive electron transfer pathways (mechanisms), the natures of which are dependent on secondary structure. Following on from this, electron transfer within a series of well-defined helical peptides, constrained by either Huisgen cycloaddition, ring-closing metathesis, or a lactam bridge, was determined. The electrochemical results indicate that each constrained peptide, in contrast to a linear counterpart, exhibits a remarkable shift of the formal potential to the positive (>460 mV) and a significant reduction of the electron transfer rate constant (up to 15-fold), which represent two distinct electronic “on/off” states. High-level calculations demonstrate that the additional backbone rigidity provided by the side-bridge constraints leads to an increased reorganization energy barrier, which impedes the vibrational fluctuations necessary for efficient intramolecular electron transfer through the peptide backbone. Further calculations reveal a clear mechanistic transition from hopping to superexchange (tunneling) stemming from side-bridge gating. We then extended our research to fine-tuning of the electronic properties of peptides through both structural and chemical manipulation, to reveal an interplay between electron-rich side chains and backbone rigidity on electron transfer. Further to this, we explored the possibility that the side-bridge constraints present in our synthetic peptides provide an additional electronic transport pathway, which led to the discovery of two distinct forms of quantum interferometer. The effects of destructive quantum interference appear essentially through both the backbone and an alternative tunneling pathway provided by the side bridge in the constrained β-strand peptide, as evidenced by a correlation between electrochemical measurements and conductance simulations for both linear and constrained β-strand peptides. In contrast, an interplay between quantum interference effects and vibrational fluctuations is revealed in the linear and constrained 310-helical peptides.

Understanding glycome changes in diabetic ovarian tissue

28 August 2018:

This paper describes the characterization of protein glycosylation in the ovary and measures the changes that occur with the induction of diabetes. The lead author on the paper is CNBP PhD student Abdulrahman M Shathili from Macquarie University (pictured).

Journal: Glycobiology.

Publication title: The effect of streptozotocin-induced hyperglycemia on N-and O-linked protein glycosylation in mouse ovary.

Authors: Abdulrahman M Shathili, Hannah M Brown, Arun V Everest-Dass, Tiffany C Y Tan, Lindsay M Parker, Jeremy G Thompson, Nicolle H Packer.

Abstract: Post-translational modification of proteins namely glycosylation influences cellular behavior, structural properties and interactions including during ovarian follicle development and atresia. However, little is known about protein glycosylation changes occurring in diabetes mellitus in ovarian tissues despite the well-known influence of diabetes on the outcome of successful embryo implantation. In our study, the use of PGC chromatography–ESI mass spectrometry in negative ion mode enabled the identification of 138 N-glycans and 6 O-glycans on the proteins of Streptozotocin-induced (STZ) diabetic mouse ovarian tissues (n = 3). Diabetic mouse ovaries exhibited a relative decrease in sialylation, fucosylation and, to a lesser extent, branched N-linked glycan structures, as well as an increase in oligomannose structures on their proteins, compared with nondiabetic mouse ovaries. Changes in N-glycans occurred in the diabetic liver tissue but were more evident in diabetic ovarian tissue of the same mouse, suggesting an organ-specific effect of diabetes mellitus on protein glycosylation. Although at a very low amount, O-GalNAc glycans of mice ovaries were present as core type 1 and core type 2 glycans; with a relative increase in the NeuGc:NeuAc ratio as the most significant difference between control and diabetic ovarian tissues. STZ-treated mice also showed a trend towards an increase in TNF-α and IL1-B inflammatory cytokines, which have previously been shown to influence protein glycosylation.

New nanoparticles help detect deep-tissue cancers

6 August 2018:

Researchers have developed a new form of nanoparticle and associated imaging technique that can detect multiple disease biomarkers, including those for breast cancer, found in deep-tissue in the body.

Reported in the science journal ‘Nature Nanotechnology’, the research opens up a new avenue in minimally invasive disease diagnosis and will potentially have widespread use both for biomedical research and for clinical applications.

“The use of nanoparticles for bio-imaging of disease is an exciting and fast-moving area of science,” says research author Dr Yiqing Lu (pictured) at the ARC Centre of Excellence for Nanoscale BioPhotonics (CNBP), Macquarie University.

“Specially designed nanoparticles can be placed in biological samples or injected into specific sites of the body and then ‘excited’ by introduced light such as that from a laser or an optical fibre,” he says.

“Disease biomarkers targeted by these nanoparticles then reveal themselves, by emitting their own specific wavelength signatures which are able to be identified and imaged.”

A major limitation however is that only a single disease biomarker at a time is able to be distinguished and quantified in the body using this type of detection technique.

“Detection of multiple biomarkers (known as multiplexing) in the body has been a major challenge for researchers,” says Dr Lu.

“The tissue environment is extremely complex—full of light absorbing and scattering elements such as blood, muscle and cartilage. And introducing multiple nanoparticles to a site, operating at multiple wavelengths to detect multiple biomarkers, produces too much interference. It makes it extremely difficult to determine accurately if a range of disease biomarkers are present.”

What Dr Lu and the research team have done to solve this issue has been to engineer innovative nanoparticles that emit light at the same frequency (near infrared light) but that are able to be coded to emit light for set periods of time (in the microsecond-to-millisecond time range).

“It is the duration of the light-emission and the biomarker reaction to this timed amount of light (known as luminescence lifetime) that produces a clearly identifiable molecular signature,” he says.

“Multiple disease biomarkers can be clearly identified and imaged based on this approach as there are no overlapping wavelengths interfering with the reading.”

“This enables high-contrast optical biomedical imaging that can detect multiple disease biomarkers all at the one time.” says Dr Lu.

In an exciting breakthrough in laboratory testing, the innovative nanoparticles have been able to detect multiple forms of breast cancer tumours in mice.

“We’re extremely excited where this work is taking us,” says Professor Fan Zhang at Fudan University (China) and joint-lead author on the research publication.

“We were able to successfully detect and identify key biomarkers for a number of different sub-types of breast cancer.”

“This technique has the potential to provide a low-invasive method of determining if breast cancer is present, as well as the form of breast cancer, without the need to take tissue samples via biopsy.”

“Ultimately our novel nanoparticles will enable quantitative assessment for a wide range of disease and cancer biomarkers, all at one time. The technique will be able to be used for early-stage disease screening and potentially utilised in integrated therapy,” says Professor Fan Zhang.

Professor Jim Piper, CNBP node leader at Macquarie University and also an author on the paper is similarly upbeat with the results that have been obtained.

“This is a major advance in a long-term effort at our Centre at Macquarie University to develop innovative techniques for simultaneous detection of multiple disease markers in humans and animals,” he says.

“Next steps in our research collaboration are to further refine the nanoparticles, to examine issues related to a clinical roll-out of the technology and to explore further applications and disease areas where this technique could be best utilised.”

Reported in the prestigious journal ‘Nature Nanotechnology’, the international team of researchers involved with the study are based at the ARC Centre of Excellence for Nanoscale BioPhotonics (CNBP), Macquarie University and Fudan University, China.

Notably, the work is an extension of previous nanoparticle-imaging research undertaken by Dr Lu at Macquarie University which has been awarded a patent in the United States and China, and which has already been licensed with commercial partners.

Journal: Nature Nanotechnology.

Publication title: Lifetime-engineered NIR-II nanoparticles unlock multiplexed in vivo imaging.

Authors: Yong Fan, Peiyuan Wang, Yiqing Lu, Rui Wang, Lei Zhou, Xianlin Zheng, Xiaomin Li, James A. Piper & Fan Zhang.

Below: A stylised image of cancer detecting nanoparticles in the body. Credit: Yong Fan.

Engineering protein-based nanoparticles

23 July 2018:

A new review paper has been published in the journal ‘Genes’ featuring two CNBP Associate Investigators as co-authors, Dr Andrew Care (Cancer Institute NSW) and Dr Anwar Sunna (Macquarie University).

Titled, ‘Bioengineering Strategies for Protein-based Nanoparticles’, the paper focuses on the tools available to custom-engineer protein-based nanoparticles for different applications, including those in nanomedicine and biotechnology.

First author of the paper, and co-supervised by Dr Care and Dr Sunna is Ms Dennis Diaz (pictured left in photo).

Journal: Genes.

Publication title: Bioengineering Strategies for Protein-Based Nanoparticles.

Authors: Dennis Diaz, Andrew Care and Anwar Sunna.

Abstract: In recent years, the practical application of protein-based nanoparticles (PNPs) has expanded rapidly into areas like drug delivery, vaccine development, and biocatalysis. PNPs possess unique features that make them attractive as potential platforms for a variety of nanobiotechnological applications. They self-assemble from multiple protein subunits into hollow monodisperse structures; they are highly stable, biocompatible, and biodegradable; and their external components and encapsulation properties can be readily manipulated by chemical or genetic strategies. Moreover, their complex and perfect symmetry have motivated researchers to mimic their properties in order to create de novo protein assemblies. This review focuses on recent advances in the bioengineering and bioconjugation of PNPs and the implementation of synthetic biology concepts to exploit and enhance PNP’s intrinsic properties and to impart them with novel functionalities.

A photoresponsive LPD system developed

19 July 2018:

CNBP researchers have published a paper reporting on  the development of a novel photoresponsive liposome-polycation-DNA (LPD) platform. Lead author on the paper was Wenjie Chen (pictured).

Journal: Journal of Materials Chemistry B.

Publication title: Photoresponsive endosomal escape enhances gene delivery using liposome-polycation-DNA (LPD) nanovector.

Authors: Wenjie Chen, Wei Deng, Xin Xu, Xiang Zhao, Jenny Nhu Vo, Ayad G. Anwer, Thomas C. Williams, Haixin Cui, Ewa M. Goldys.

Abstract: Lipid-based nanocarriers with stimuli responsiveness have been utilized as controlled release systems for gene/drug delivery applications. In our work, by taking advantage of high complexation capbility of polycations and the light triggered property, we designed a novel photoresponsive liposome-polycation-DNA (LPD) platform. This LPD carrier incorporates verteporfin (VP) in lipid bilayers and the complex of polyethylenimine (PEI)/plasmid DNA (pDNA) encoding EGFP (polyplex) in the central cavities of liposomes. The liposomes were formulated with cationic lipids, PEGylated neutral lipids and cholesterol molecules, which improve their stability and cellular uptake in the serum-containing media. We evaluated the nanocomplex stability by monitoring size changes over six days, and the celluar uptake of nanocomplex by imaging the intracellular route. We also demonstrated light triggered the cytoplasmic release of pDNA upon irradiation with a 690 nm LED light source. Furthermore this light triggered mechanism has been studied at subcellular level. The activated release is driven by the generation of reactive oxygen species (ROS) from VP after light illumination. These ROS oxidize and destabilize the liposomal and endolysosomal membranes, leading to the release of pDNA into the cytosol and subsequent gene transfer activities. Light-triggered endolysosomal escape of pDNA at different time points was confirmed by quantitative analysis of colocalization between pDNA and endolysosomes. The increased expression of the reporter EGFP in human colorectal cancer cells was also quantified after light illumination at various time points. The efficiency of this photo-induced gene transfection was demonstrated to be more than double compared to non-irradiated controls. Additionally, we observed reduced cytotoxicity of the LPDs compared with the polyplexes alone. This study have thus shown that light-triggered and biocompatible LPDs enable improved control of efficient gene delivery which will be beneficial for future gene therapies.