29 March 2019:
Liquid-metal nanoparticles can focus ultraviolet light at the nanoscale. Read more in a publication reporting on the UV plasmonic properties of colloidal gallium-indium particles (lead author CNBP Associate Investigator Dr Philipp Reineck, RMIT University).
Journal: Scientific Reports.
Publication title: UV plasmonic properties of colloidal liquid-metal eutectic gallium-indium alloy nanoparticles.
Authors: Philipp Reineck, Yiliang Lin, Brant C. Gibson, Michael D. Dickey, Andrew D. Greentree, Ivan S. Maksymov.
Abstract: Nanoparticles made of non-noble metals such as gallium have recently attracted significant attention due to promising applications in UV plasmonics. to date, experiments have mostly focused on solid and liquid pure gallium particles immobilized on solid substrates. However, for many applications, colloidal liquid-metal nanoparticle solutions are vital. Here, we experimentally demonstrate strong UV plasmonic resonances of eutectic gallium-indium (eGaIn) liquid-metal alloy nanoparticles suspended in ethanol. We rationalise experimental results through a theoretical model based on Mie theory. our results contribute to the understanding of UV plasmon resonances in colloidal liquid-metal eGaIn nanoparticle suspensions. they will also enable further research into emerging applications of UV plasmonics in biomedical imaging, sensing, stretchable electronics, photoacoustics, and electrochemistry.
14 February 2019:
Congratulations to CNBP Associate Investigator Dr Philipp Reineck (RMIT VC Research Fellow), who has been awarded an RMIT University School of Science ‘Early Career Researcher Award’ for his outstanding research outputs and achievements in 2018.
Recognized was Philipp’s publication output. This included ten papers (with three officially published in 2019). Also his four invited talks given at international conferences in the USA, Europe and Australia, together with his successful funding from the Australian Synchrotron to do 3D bioimaging experiments at the Spanish synchrotron.
A fantastic effort Philipp!
Below – Dr Philipp Reineck receiving his award.
28 January 2019:
Hundreds of individual tiny fluorescent diamond particles have been imaged and characterized by CNBP researchers, reported in the journal ‘Particle & Particle Systems Characterization’.
Fluorescent nanodiamonds (FNDs) are vital to many emerging nanotechnological applications, from bioimaging and sensing to quantum nanophotonics.
The study identifies opportunities to improve the properties of single fluorescent nanodiamonds, to develop a better understanding of their underlying physical mechanisms and to advance current nanofabrication technologies.
Lead author on the paper is CNBP Associate Investigator Dr Philipp Reineck at RMIT University.
Journal: Particle & Particle Systems Characterization.
Publication title: Not All Fluorescent Nanodiamonds Are Created Equal: A Comparative Study.
Authors: Philipp Reineck; Leevan Fremiot Trindade, Jan Havlik, Jan Stursa, Ashleigh Heffernan, Aaron Elbourne, Antony Orth, Marco Capelli, Petr Cigler, David A. Simpson, Brant C. Gibson.
Abstract: Fluorescent nanodiamonds (FNDs) are vital to many emerging nanotechnological applications, from bioimaging and sensing to quantum nanophotonics. Yet, understanding and engineering the properties of fluorescent defects in nanodiamonds remain challenging. The most comprehensive study to date is presented, of the optical and physical properties of five different nanodiamond samples, in which fluorescent nitrogen‐vacancy (NV) centers are created using different fabrication techniques. The FNDs’ fluorescence spectra, lifetime, and spin relaxation time (T1) are investigated via single‐particle confocal fluorescence microscopy and in ensemble measurements in solution (T1 excepted). Particle sizes and shapes are determined using scanning electron microscopy and correlated with the optical results. Statistical tests are used to explore correlations between the properties of individual particles and also analyze average results to directly compare different fabrication techniques. Spectral unmixing is used to quantify the relative NV charge‐state (NV− and NV0) contributions to the overall fluorescence. A strong variation is found and quantified in the properties of individual particles within all analyzed samples and significant differences between the different particle types. This study is an important contribution toward understanding the properties of NV centers in nanodiamonds. It motivates new approaches to the improved engineering of NV‐containing nanodiamonds for future applications.
6 February 2018:
Tiny 5 nm detonation nanodiamonds glow in different colors and their fluorescence is pH dependent, reports a new paper by CNBP scientists published today in the Nature journal Scientific Reports.
Lead author of the paper Dr Philipp Reineck from RMIT University (Former CNBP Research Fellow and current CNBP Associate Investigator) notes that the research is particulalry exciting as the fluorescence lifetime of the detonation nanodiamonds makes fluorescence lifetime imaging (FLIM) for bioimaging applications feasible.
Journal: Scientific Reports.
Publication title: Visible to near-IR fluorescence from single-digit detonation nanodiamonds: excitation wavelength and pH dependence.
Authors: Philipp Reineck, Desmond W. M. Lau, Emma R. Wilson, Nicholas Nunn, Olga A. Shenderova & Brant C. Gibson.
Abstract: Detonation nanodiamonds are of vital significance to many areas of science and technology. However, their fluorescence properties have rarely been explored for applications and remain poorly understood. We demonstrate significant fluorescence from the visible to near-infrared spectral regions from deaggregated, single-digit detonation nanodiamonds dispersed in water produced via post-synthesis oxidation. The excitation wavelength dependence of this fluorescence is analyzed in the spectral region from 400 nm to 700 nm as well as the particles’ absorption characteristics. We report a strong pH dependence of the fluorescence and compare our results to the pH dependent fluorescence of aromatic hydrocarbons. Our results significantly contribute to the current understanding of the fluorescence of carbon-based nanomaterials in general and detonation nanodiamonds in particular.
11 November 2017:
Fantastic TV talents (and CNBP researchers) Prof Brant Gibson and Dr Philipp Reineck from RMIT University featured on SCOPE TV for kids, 11th November 2017.
Check them out as they discuss the use of diamond nanoparticles in biophotonics to help shed light on cells and the living body!
31 October 2017:
Surface chemistry is vital for nanodiamond fluorescence, reports a new paper published by CNBP researchers (lead author Dr Philipp Reineck pictured). The paper was published in the journal ‘ACS Nano’ and is available online.
Journal: ACS Nano.
Publication title: Effect of Surface Chemistry on the Fluorescence of Detonation Nanodiamonds.
Authors: Philipp Reineck, Desmond W. M. Lau, Emma R. Wilson, Kate Fox, Matthew R. Field, Cholaphan Deeleepojananan, Vadym N. Mochalin, and Brant C. Gibson.
Abstract: Detonation nanodiamonds (DNDs) have unique physical and chemical properties that make them invaluable in many applications. However, DNDs are generally assumed to show weak fluorescence, if any, unless chemically modified with organic molecules. We demonstrate that detonation nanodiamonds exhibit significant and excitation-wavelength-dependent fluorescence from the visible to the near-infrared spectral region above 800 nm, even without the engraftment of organic molecules to their surfaces. We show that this fluorescence depends on the surface functionality of the DND particles. The investigated functionalized DNDs, produced from the same purified DND as well as the as-received polyfunctional starting material, are hydrogen, hydroxyl, carboxyl, ethylenediamine, and octadecylamine-terminated. All DNDs are investigated in solution and on a silicon wafer substrate and compared to fluorescent high-pressure high-temperature nanodiamonds. The brightest fluorescence is observed from octadecylamine-functionalized particles and is more than 100 times brighter than the least fluorescent particles, carboxylated DNDs. The majority of photons emitted by all particle types likely originates from non-diamond carbon. However, we locally find bright and photostable fluorescence from nitrogen-vacancy centers in diamond in hydrogenated, hydroxylated, and carboxylated detonation nanodiamonds. Our results contribute to understanding the effects of surface chemistry on the fluorescence of DNDs and enable the exploration of the fluorescent properties of DNDs for applications in theranostics as nontoxic fluorescent labels, sensors, nanoscale tracers, and many others where chemically stable and brightly fluorescent nanoparticles with tailorable surface chemistry are needed.
3 July 2017:
Researchers from CNBP’s RMIT University node (lead author CNBP PhD student Marco Capelli pictured), have had a paper published in the journal ‘Nanoscale’.
The researchers report an enhancement of the nitrogen-vacancy (NV) quantum yield by up to 7% in bulk diamond caused by an external magnetic field.
The paper is accessible online.
Publication title: Magnetic field-induced enhancement of the nitrogen-vacancy fluorescence quantum yield .
Authors: M. Capelli, P. Reineck, D. W. M. Lau, A. Orth, J. Jeske, M. W. Doherty, T. Ohshima, A. D. Greentree and B. C. Gibson.
Abstract: The nitrogen-vacancy (NV) centre in diamond is a unique optical defect that is used in many applications today and methods to enhance its fluorescence brightness are highly sought after. We observed experimentally an enhancement of the NV quantum yield by up to 7% in bulk diamond caused by an external magnetic field relative to the field-free case. This observation is rationalised phenomenologically in terms of a magnetic field dependence of the NV excited state triplet-to-singlet transition rate. The theoretical model is in good qualitative agreement with the experimental results at low excitation intensities. Our results significantly contribute to our fundamental understanding of the photophysical properties of the NV defect in diamond.
1 June 2017:
CNBP was well represented at the 11th International Conference on New Diamond and Nano Carbons, held in Cairns, Australia, 28th May – June 1, 2017.
CNBP Chief Investigator A/Prof Brant Gibson was Co-chair of the conference (pictured) with CNBP researcher Dr Philipp Reineck a contributing speaker, presenting on ‘Bright and photostable nitrogen‐vacancy fluorescence from unprocessed detonation nanodiamonds’.
Also providing a contributing talk was CNBP’s Dr Lindsay Parker, ‘Applications of fluorescent nanodiamonds in cellular molecular tracing.’
Additionally, CNBP’s Andrew Greentree, Ivan Maksymov, Daniel Drumm, Ashleigh Heffernan, Marco Capelli, Nicole Cordina and Emma Wilson gave poster presentations and Brooke Bacon and Desmond Lau provided administrative and technical support respectively.
The conference spanned research topics from fundamental physical and chemical concepts to applied technologically driven applications with carbon based materials. This including single crystal diamond, nanodiamonds, carbon nanotubes, graphene and other carbon nanostructures.
17 May 2017:
CNBP’s Dr Philipp Reineck has given a talk at the Aimé-Cotton Laboratory (LAC), Paris, which he is currently visiting as a guest researcher.
The laboratory is a joint research unit of the National Center for Scientific Research (CNRS), the University of Paris-Sud and the Ecole Normale Supérieure de Cachan.
Philipp’s talk consisted of an overview of CNBP science and more specifically, focused on Centre projects across the nano-diamond sensing and bio-imaging space.
10 May 2017:
Dr Philipp Reineck, CNBP Research Fellow, has given an invited talk at the ENM Nanoparticle meeting in San Sebastian in Spain, 10 May 2017.
His talk was titled, ‘Near-IR fluorescent nanomaterials for bioimaging and sensing applications.’ Dr Reineck also chaired a workshop/session on nanoparticles for optical bioimaging.
Further information on the conference can be found online.