Dynamic in-situ sensing of fluid-dispersed 2D materials integrated on microfluidic Si chip

This is the author accepted manuscript. The final version is available from Nature Publishing Group via the DOI in this record.The supplementary videos associated with this article are located in ORE at: https://doi.org/10.24378/exe.1643In this work, we propose a novel approach for wafer-scale integration of 2D materials on CMOS photonics chip utilising methods of synthetic chemistry and microfluidics technology. We have successfully demonstrated that this approach can be used for integration of any fluid-dispersed 2D nano-objects on silicon-on-insulator photonics platform. We demonstrate for the first time that the design of an optofluidic waveguide system can be optimised to enable simultaneous in-situ Raman spectroscopy monitoring of 2D dispersed flakes during the device operation. Moreover, for the first time, we have successfully demonstrated the possibility of label-free 2D flake detection via selective enhancement of the Stokes Raman signal at specific wavelengths. We discovered an ultra-high signal sensitivity to the xyz alignment of 2D flakes within the optofluidic waveguide, which in turn enables precise in-situ alignment detection for the first practicable realisation of 3D photonic microstructure shaping based on 2D-fluid composites and CMOS photonics platform while also representing a useful technological tool for the control of liquid phase deposition of 2D materials.We acknowledge financial support from: The Engineering and Physical Sciences Research Council (EPSRC) of the United Kingdom via the EPSRC Centre for Doctoral Training in Electromagnetic Metamaterials (Grant No. EP/L015331/1) and also via Grant Nos. EP/N035569/1, EP/G036101/1, EP/M002438/1, and EP/M001024/1, Science Foundation Ireland Grant No. 12/IA/1300, the Ministry of Education and Science of the Russian Federation (Grant No. 14.B25.31.0002) and the Royal Society International Exchange Grant 2015/R3. The microfluidic structures were fabricated at Tyndall National Institute under the Science Foundation Ireland NAP368 and NAP94 programs

Rare Earth Doped Silica Nanoparticles via Thermolysis of a Single Source Metallasilsesquioxane Precursor

Rare earth metal doped silica nanoparticles have significant advantages over traditional organic dyes and quantum dots. Silsesquioxanes are promising precursors in the production of silica nanoparticles by thermolysis, due to their structural similarities with silica materials. This manuscript describes the production of a new Eu3+-based metallasilsesquioxane species and its use as a single source precursor in the thermolytic production of luminescent rare earth metal doped silica nanoparticles with characteristic emission in the visible region of the spectrum

Magnetically activated adhesives: towards on-demand magnetic triggering of selected polymerisation reactions

On-demand initiation of chemical reactions is becoming increasingly popular in many areas. The use of a magnetic field to trigger reactions is an intriguing concept, with vast potential in both research and industrial settings, though it remains a challenge as yet unsolved. Here we report the first example of on-demand magnetic activation of a polymerisation process using an anaerobic adhesive formulation as an example of this new approach toward triggering polymerisation reactions using an external magnetic field. Our strategy involves the use of a colloidal system comprising functional methacrylate ester monomers, peroxide and CuII-salt as polymerisation initiators and magnetic nanoparticles coated with an oxidising shell. This unique combination prevents reduction of the reactive transition metal (CuII) ion by the metal substrates (steel or aluminium) to be joined – hence inhibiting the redox radical initiated cationic polymerisation reaction and efficiently preventing adhesion. The polymerisation and corresponding adhesion process can be triggered by removal of the functional magnetic particles using a permanent external magnet either prior to formulation application or at the joint to be adhered, enabling the polymerisation to proceed through CuII-mediated reduction. This new approach enables on-demand magnetically-triggered reaction initiation and holds potential for a range of useful applications in chemistry, materials science and relevant industrial manufacturing

Large area quantum dot luminescent solar concentrators for use with dye-sensitised solar cells

Green-emitting quantum dot luminescent solar concentrators are used to sensitise an optically-matched dye-sensitised solar cell.</p

Effects of long-term exposure of gelatinated and non-gelatinated cadmium telluride quantum dots on differentiated PC12 cells

Background: The inherent toxicity of unmodified Quantum Dots (QDs) is a major hindrance to their use in biological applications. To make them more potent as neuroprosthetic and neurotherapeutic agents, thioglycolic acid (TGA) capped CdTe QDs, were coated with a gelatine layer and investigated in this study with differentiated pheochromocytoma 12 (PC12) cells. The QD - cell interactions were investigated after incubation periods of up to 17 days by MTT and APOTOX-Glo Triplex assays along with using confocal microscopy. Results: Long term exposure (up to 17 days) to gelatinated TGA-capped CdTe QDs of PC12 cells in the course of differentiation and after neurites were grown resulted in dramatically reduced cytotoxicity compared to nongelatinated TGA-capped CdTe QDs. Conclusion: The toxicity mechanism of QDs was identified as caspase-mediated apoptosis as a result of cadmium leaking from the core of QDs. It was therefore concluded that the gelatine capping on the surface of QDs acts as a barrier towards the leaking of toxic ions from the core QDs in the long term (up to 17 days)

Improved Caesium sorption kinetics through the magnetic disaggregation of Cu-HCF (II) nanoparticles A Magnetic templating effect

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Videos of the effect of applied electric fields and laser excitation on the orientation and position of 2D materials dispersed in nematic liquid crystals

1: Orientation switching of a graphene flake, dispersed in E7, in a 50 μm diameter microfluidic reservoir. A pulsed electrical field is applied and a corresponding change in the flake alignment and patterning of the LC surface are observed. The video was taken using cross-polarised light. 2: Induced motion of GO flakes, dispersed in E7, in an 11.6 μm wide channel. A bias is applied across the channel and is steadily increased. Switching of the LC director occurs above a threshold applied field strength of 0.25 V/μm. As the LC director is switched, motion of the dispersed GO flakes is observed. The video was taken with cross-polarised light. 3: Induced motion of a single GO flake, dispersed in MLC-6608, in an 11.6 μm wide channel. An electric field is applied across the channel and is increased and decreased periodically above and below the threshold applied field strength. Induced rotational and translational motion of the flake is observed. The video was taken using unpolarised light. 4: Optically induced motion of GO flakes, dispersed in MLC-6608, in a 50 μm diameter microfluidic reservoir is observed. Motion can be seen as a change in the interference pattern of the backscattered light from the Raman laser. Optical trapping with particles drawn to high light intensity regions is observed.The article associated with this dataset is located in ORE at: http://hdl.handle.net/10871/25352Supplementary videos for the Hogan et al. (2017) article "Dynamic in-situ sensing of fluid-dispersed 2D materials integrated on microfluidic Si chip" published in Scientific Reports.Engineering and Physical Sciences Research Council (EPSRC)Engineering and Physical Sciences Research Council (EPSRC)Engineering and Physical Sciences Research Council (EPSRC)Engineering and Physical Sciences Research Council (EPSRC)Engineering and Physical Sciences Research Council (EPSRC)Science Foundation IrelandMinistry of Education and Science of the Russian FederationThe Royal Societ

Cadmium nanoparticles citrullinate cytokeratins within lung epithelial cells: cadmium as a potential cause of citrullination in chronic obstructive pulmonary disease

David Hutchinson,1,2 Judith M&uuml;ller,3 Joseph E McCarthy,4 Yurii K Gun&rsquo;ko,4,5 Navin Kumar Verma,6 Xuezhi Bi,7 Luisana Di Cristo,8 Laura Kickham,8 Dania Movia,8 Adriele Prina-Mello,5,8 Yuri Volkov5,8,9 1Royal Cornwall Hospital NHS Trust, Treliske, 2University of Exeter Medical School Cornwall, UK; 3University of Basel, Basel, Switzerland; 4School of Chemistry, 5Advanced Materials for BioEngineering Research Centre (AMBER), Trinity College Dublin, Dublin, Ireland; 6Lee Kong Chian School of Medicine, Nanyang Technological University, 7Bioprocessing Technology Institute, A*STAR Graduate Academy, Singapore; 8Department of Clinical Medicine, School of Medicine, Trinity College Dublin, Dublin, Ireland; 9International Laboratory of Magnetically Controlled Nanosystems for Theranostics of Oncological and Cardiovascular Diseases, ITMO University, St. Petersburg, Russia Objective: The objective of the study was to determine whether the cadmium-derived materials induce intracellular protein citrullination. Methods: Human A549 lung epithelial cells were exposed to cadmium in soluble and nanoparticulate forms represented by cadmium chloride (CdCl2) and cadmium oxide (CdO), respectively, and their combinations with ultrafine carbon black (ufCB) produced by high temperature combustion, imitating cigarette burning. Protein citrullination in cell lysates was analyzed by Western immunoblotting and verified by immunofluorescent confocal microscopy. Target citrullinated proteins were identified by proteomic analysis. Results: CdO, ufCB and its combination with CdCl2 and CdO after high temperature combustion induced protein citrullination in cultured human lung epithelial cells, as detected by immunoblotting with anti-citrullinated protein antibody. Cytokeratins of type II (1, 2, 5, 6A, 6B and 77) and type I (9, 10) were identified as major intracellular citrullination targets. Immunofluorescent staining confirmed the localization of citrullinated proteins both in the cytoplasm and cell nuclei. Conclusion: Cadmium oxide nanoparticle exposure facilitated post-translational citrullination of proteins. Keywords: cadmium, COPD, nanoparticles, cytokeratins, citrullination, autoimmunity, proteomic