Functionalized Luminescent Silica Nanoparticles with Chelate Groups on Interface: Synthesis and Characterization

Design, synthesis and characterization of luminescent silica nanoparticles with chelate groups on surface as well as the synthesis of new organosilanes with amino and carboxyl groups for silica surface functionalization is presented. When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/3512

Augmented Reality Mobile apps Development with Unity and Vuforia SDK

This paper shows how to create an animation of a game character for a mobile application with augmented reality. The Unity platform, Vuforia SDK and Android OS were used for work. For this work, the Fighting Unity-Chan model was downloaded. This is an animation resource pack that specializes in fighting or action games. This code shows how a button is created (GUI.Button), it assigns an animation that will work when you click on it, the size of the button and its name. To create a smooth and correct transition between animations, Animator was created, in which all animations are shown taking into account the time of their action. For example, to switch from a state of rest (Idle) to some other state, for example, to a state of impact (Hicick), it is necessary to spend time in the amount of 1 second

Luminescent composite based on epoxy polymer and silica nanoparticles doped by terbium(III) complex

© 2020, Springer Nature B.V. The interaction of the NPEL-128 epoxy oligomer with silica nanoparticles doped with terbium(III) complex with p-sulfonatothiacalix[4]arene was studied for two types of nanoparticles: possessing silanol hydroxyl groups on the non-modified surface of the nanoparticles (SNs) or amino and hydroxyl groups on the amino-modified silica surface (ASNs). The possible reaction schemes of amino and hydroxyl groups on the surface of ASNs with epoxy molecules were revealed using IR spectroscopy and DSC. Based on the obtained data, a method for producing epoxy nanocomposites was developed, and their thermophysical, physicomechanical, and luminescent properties were investigated. The chemical bonding of epoxy with ASNs compared with that of SNs allows one to obtain a higher dispersion and uniform distribution of the nanoparticles in the polymer matrix, as well as to increase the glass transition temperature of the polymer. Due to the presence of terbium(III) complex in silica nanoparticles, the cured epoxyamine polymer filled by ASNs exhibits luminescent properties. [Figure not available: see fulltext.

Rhenium Nanoclusters as Modifiers of Immunosensors in the Determination of Tricyclic Antidepressants

Abstract: The properties of hexarhenium chalcogenide nanoclusters (K4[{Re6S8}(OH)6]·8H2O and K4[{Re6S8}(CN)6]·8H2O) in combination with carbon nanomaterials (carbon nanotubes and graphene oxide) are studied by voltammetry, electrochemical impedance spectroscopy, atomic force microscopy, and spectrophotometry and their screening is performed for use as hybrid modifiers of screen-printed graphite electrodes in immunosensors in order to improve analytical characteristics. The high negative charge of nanoclusters can be considered the driving force of the adsorption of clusters in the formation of electrodes modified by hybrid nanomaterials. It was found that hexarhenium chalcogenide nanoclusters possess electrochemical activity, which was first used to register immunochemical interactions. The change in the resistance of electron transfer made it possible to choose the best hybrid nanomaterials. The parameters of the surface roughness of the modified electrodes associated with the height properties of the irregularities were estimated. The use of hexarhenium chalcogenide nanoclusters in combination with carbon nanomaterials as hybrid nanomodifiers has made it possible to develop highly sensitive and selective amperometric and impedimetric immunosensors for the determination of tricyclic antidepressants (amitriptyline, desipramine, and imipramine) in pharmaceuticals and urine. The limit of quantification (LOQ) is at the level (4–7) × 10–11 M. The relative standard deviation does not exceed 5%

Paramagnetic Relaxation Enhancement in Hydrophilic Colloids Based on Gd(III) Complexes with Tetrathia-and Calix[4]arenes

Copyright © 2020 American Chemical Society. Hydrophilic colloids (PSS-[Ln2(TCAi)2] and PSS-[LnCAi], where i = 1, 2, or 3 and Ln = Gd or Tb) were prepared by precipitation of Gd(III) or Tb(III) complexes with tetrathiacalix[4]arenes (TCAi) and calix[4]arenes bearing two 1,3-diketone groups (CAi) from dimethylformamide to an aqueous solution of poly(sodium 4-styrenesulfonate) (PSS). Dynamic light scattering and transmission electron microscopy demonstrated the formation of nanoparticles coated by the polymer. Luminescence decay measurements on Tb(III)-based colloids allowed hydration numbers of 2 and 4 per metal ion to be determined for PSS-[Ln2(TCAi)2] and PSS-[LnCAi] samples, respectively. Longitudinal and transverse water proton relaxivity values measured at 20.8 MHz were remarkably high for the PSS-[GdCAi] colloids but unexpectedly low for the PSS-[Gd2(TCAi)2] ones. 1H fast field cycling nuclear magnetic resonance relaxometry was applied to shed light on the origin of the different relaxation enhancement in the investigated systems. Extremely slow exchange with the bulk of water molecules coordinated to Gd(III) and the scarce accessibility of Gd(III) sites to water were highlighted as the main causes of limited relaxivity

Single excited dual band luminescent hybrid carbon dots-terbium chelate nanothermometer

The report introduces hybrid polyelectrolyte-stabilized colloids combining blue and green-emitting building blocks, which are citrate carbon dots (CDs) and [TbL]+ chelate complexes with 1,3-diketonate derivatives of calix[4]arene. The joint incorporation of green and blue-emitting blocks into the polysodium polystyrenesulfonate (PSS) aggregates is carried out through the solvent-exchange synthetic technique. The coordinative binding between Tb3+ centers and CD surface groups in initial DMF solutions both facilitates joint incorporation of [TbL]+ complexes and the CDs into the PSS-based nanobeads and affects fluorescence properties of [TbL]+ complexes and CDs, as well as their ability for temperature sensing. The variation of the synthetic conditions is represented herein as a tool for tuning the fluorescent response of the blue and green-emitting blocks upon heating and cooling. The revealed regularities enable developing either dual-band luminescent colloids for monitoring temperature changes within 25–50 °C through double color emission or transforming the colloids into ratiometric temperature sensors via simple concentration variation of [TbL]+ and CDs in the initial DMF solution. Novel hybrid carbon dots-terbium chelate PSS-based nanoplatform opens an avenue for a new generation of sensitive and customizable single excited dualband nanothermometers

Terbium(III)-thiacalix[4]arene nanosensor for highly sensitive intracellular monitoring of temperature changes within the 303–313 K range

© 2020, The Author(s). The work introduces hydrophilic PSS-[Tb2(TCAn)2] nanoparticles to be applied as highly sensitive intracellular temperature nanosensors. The nanoparticles are synthesized by solvent-induced nanoprecipitation of [Tb2(TCAn)2] complexes (TCAn - thiacalix[4]arenes bearing different upper-rim substituents: unsubstituted TCA1, tert-buthyl-substituted TCA2, di- and tetra-brominated TCA3 and TCA4) with the use of polystyrenesulfonate (PSS) as stabilizer. The temperature responsive luminescence behavior of PSS-[Tb2(TCAn)2] within 293–333 K range in water is modulated by reversible changes derived from the back energy transfer from metal to ligand (M* → T1) correlating with the energy gap between the triplet levels of ligands and resonant 5D4 level of Tb3+ ion. The lowering of the triplet level (T1) energies going from TCA1 and TCA2 to their brominated counterparts TCA3 and TCA4 facilitates the back energy transfer. The highest ever reported temperature sensitivity for intracellular temperature nanosensors is obtained for PSS-[Tb2(TCA4)2] (SI = 5.25% K−1), while PSS-[Tb2(TCA3)2] is characterized by a moderate one (SI = 2.96% K−1). The insignificant release of toxic Tb3+ ions from PSS-[Tb2(TCAn)2] within heating/cooling cycle and the low cytotoxicity of the colloids point to their applicability in intracellular temperature monitoring. The cell internalization of PSS-[Tb2(TCAn)2] (n = 3, 4) marks the cell cytoplasm by green Tb3+-luminescence, which exhibits detectable quenching when the cell samples are heated from 303 to 313 K. The colloids hold unprecedented potential for in vivo intracellular monitoring of temperature changes induced by hyperthermia or pathological processes in narrow range of physiological temperatures

Structure impact on photodynamic therapy and cellular contrasting functions of colloids constructed from dimeric Au(I) complex and hexamolybdenum clusters

Electrostatically driven self-assembly of [Au2L2]2+ (L is cyclic PNNP ligand) with [{Mo6I8}(L')6]2− (L' = I−, CH3COO−) in aqueous solutions is introduced as facile route for combination of therapeutic and cellular contrasting functions within heterometallic colloids (Mo6-Au2). The nature of L' affects the size and aggregation behavior of crystalline Mo6-Au2 aggregates, which in turn affect the luminescence of the cluster units incorporated into Mo6-Au2 colloids. The spin trap facilitated electron spin resonance spectroscopy technique indicates that the level of ROS generated by Mo6-Au2 colloids is also affected by their size. Both (L' = I−, CH3COO−) Mo6-Au2 colloids undergo cell internalization, which is enhanced by their assembly with poly-DL-lysine (PL) for L' = CH3COO−, but remains unchanged for L' = I−. The colloids PL-Mo6-Au2 (L' = CH3COO−) are visualized as huge crystalline aggregates both outside and inside the cell cytoplasm by confocal microscopy imaging of the incubated cells, while the smaller sized (30–50 nm) PL-Mo6-Au2 (L' = I−) efficiently stain the cell nuclei. Quantitative colocalization analysis of PL-Mo6-Au2 (L' = CH3COO−) in lysosomal compartments points to the fast endo-lysosomal escape of the colloids followed by their intracellular aggregation. The cytotoxicity of PL-Mo6-Au2 differs from that of Mo6 and Au2 blocks, predominantly acting through apoptotic pathway. The photodynamic therapeutic effect of the PL-Mo6-Au2 colloids on the cancer cells correlates with their intracellular trafficking and aggregation

Functional supramolecular systems: Design and applications

The interest in functional supramolecular systems for the design of innovative materials and technologies, able to fundamentally change the world, is growing at a high pace. The huge array of publications that appeared in recent years in the global literature calls for systematization of the structural trends inherent in the formation of these systems revealed at different molecular platforms and practically useful properties they exhibit. The attention is concentrated on the topics related to functional supramolecular systems that are actively explored in institutes and universities of Russia in the last 10-15 years, such as the chemistry of host-guest complexes, crystal engineering, self-assembly and self-organization in solutions and at interfaces, biomimetics and molecular machines and devices