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The development of the microelectronics industry requiresa newelement basis with reduced size and increased functionality. The mostimportant components in modern microelectronic integrated circuitsare passive elements. One of the key challenges in order to improvethe functionality of integrated circuits is to increase the qualityof passive elements composing them. In this paper we suggest a novelapproach to increase the quality factor Q of inductors by the surfacemodification and functionalization of the metal components. Ultrasoundinduced surface modification of metal wires led to the formation ofa porous surface structure, which further can be functionalized withmagnetite nanoparticles using layer-by-layer assembly technique. Thesurface modification and deposition of magnetite nanoparticles wasinvestigated with SEM, XRD, and contact angle measurements. Additionally,inductance and resistance measurements, as the main parameters determiningthe Q-factor of inductors, were carried out. Samples with high numberof magnetic nanoparticle–polyelectrolyte bilayers demonstratea significant increase in inductance and a slight decrease in resistancein comparison to uncoated ones. The combination of these factors ledto enhancement the Q-factor of the investigated inductive elements. [ABSTRACT FROM AUTHOR]

The photocatalytic degradation of organic molecules is one of the effective ways for water purification. At this point, photocatalytic microreactor systems seem to be promising to enhance the versatility of the photoassisted degradation approach. Herein, we propose photoresponsive microcapsules prepared via layer-by-layer assembly of polyelectrolytes on the novel CaCO 3 /TiO 2 composite template cores. The preparation of CaCO 3 /TiO 2 composite particles is challenging because of the poor compatibility of TiO 2 and CaCO 3 in an aqueous medium. To prepare stable CaCO 3 /TiO 2 composites, TiO 2 nanoparticles were loaded into mesoporous CaCO 3 microparticles with a freezing-induced loading technique. The inclusion of TiO 2 nanoparticles into CaCO 3 templates was evaluated with scanning electron microscopy and elemental analysis with respect to their type, concentration, and number of loading iterations. Upon polyelectrolyte shell assembly, the CaCO 3 matrix was dissolved, resulting in microreactor capsules loaded with TiO 2 nanoparticles. The photoresponsive properties of the resulted capsules were tested by photoinduced degradation of the low-molecule dye rhodamine B in aqueous solution and fluorescently labeled polymer molecules absorbed on the capsule surface under UV light. The exposure of the capsules to UV light resulted in a pronounced degradation of rhodamine B in capsule microvolume and fluorescent molecules on the capsule surface. Finally, the versatility of preparation of multifunctional photocatalytic and magnetically responsive capsules was demonstrated by iterative freezing-induced loading of TiO 2 and magnetite Fe 3 O 4 nanoparticles into CaCO 3 templates., Competing Interests: The authors declare no competing financial interest., (Copyright © 2020 American Chemical Society.)

Remote navigation and targeted delivery of biologically active compounds is one of the current challenges in the development of drug delivery systems. Modern methods of micro- and nanofabrication give us new opportunities to produce particles and capsules bearing cargo to deploy and possess magnetic properties to be externally navigated. In this work we explore multilayer composite magnetic microcapsules as targeted delivery systems in vitro and in vivo studies under natural conditions of living organism. Herein, we demonstrate magnetic addressing of fluorescent composite microcapsules with embedded magnetite nanoparticles in blood flow environment. First, the visualization and capture of the capsules at the defined blood flow by the magnetic field are shown in vitro in an artificial glass capillary employing a wide-field fluorescence microscope. Afterward, the capsules are visualized and successfully trapped in vivo into externally exposed rat mesentery microvessels. Histological analysis shows that capsules infiltrate small mesenteric vessels whereas large vessels preserve the blood microcirculation. The effect of the magnetic field on capsule preferential localization in bifurcation areas of vasculature, including capsule retention at the site once external magnet is switched off is discussed. The research outcome demonstrates that microcapsules can be effectively addressed in a blood flow, which makes them a promising delivery system with remote navigation by the magnetic field.

Nanocomposite coatings are promising for a range of practical applications, and layer-by-layer assembly (LbL) is a versatile tool for nanocomposite formation. However, conventional LbL is a quite laborious procedure taking a lot of time to reach a sufficient thickness of the coatings required for practical applications. Herein, we proposed a novel variant of the LbL approach based on the deposition of hydrophilic polyelectrolyte molecules from a polar solvent and hydrophobic magnetite nanoparticles (NPs) from a nonpolar dispersion medium with an intermediate washing in the same polar solvent. The composite multilayers formed in this way exhibit exponential growth of the thickness and mass. On the basis of quartz crystal microbalance (QCM), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), atomic force microscopy (AFM), and surface profile measurements, we propose a model describing the driving force of multilayer formation and the factors leading to nonlinear growth of their mass and thickness. The results allow one to expand the understanding of the mechanism of the LbL assembly in order to form multifunctional nanocomposites in a more efficient way.