Spatial light modulators have become an essential tool for advanced microscopy, enabling breakthroughs in 3D, phase, and super-resolution imaging. However, continuous spatial-light modulation that is capable of capturing sub-millisecond microscopic motion without diffraction artifacts and polarization dependence is challenging. Here we present a photothermal spatial light modulator (PT-SLM) enabling fast phase imaging for nanoscopic 3D reconstruction. The PT-SLM can generate a step-like wavefront change, free of diffraction artifacts, with a high transmittance and a modulation efficiency independent of light polarization. We achieve a phase-shift > π and a response time as short as 70 µs with a theoretical limit in the sub microsecond range. We used the PT-SLM to perform quantitative phase imaging of sub-diffractional species to decipher the 3D nanoscopic displacement of microtubules and study the trajectory of a diffusive microtubule-associated protein, providing insights into the mechanism of protein navigation through a complex microtubule network.

• MeSH
• časové faktory MeSH
• interferenční mikroskopie metody   statistika a číselné údaje   MeSH
• kovové nanočástice ultrastruktura   MeSH
• lidé MeSH
• mikroskopie atomárních sil MeSH
• mikroskopie fázově kontrastní metody   statistika a číselné údaje   MeSH
• mikrotubuly metabolismus   ultrastruktura   MeSH
• nanotechnologie MeSH
• nanotrubičky ultrastruktura   MeSH
• optické jevy MeSH
• počítačová simulace MeSH
• proteiny asociované s mikrotubuly metabolismus   MeSH
• proteiny buněčného cyklu metabolismus   MeSH
• Schizosaccharomyces pombe - proteiny metabolismus   MeSH
• světlo MeSH
• tubulin metabolismus   MeSH
• zlato MeSH
• zobrazování trojrozměrné metody   statistika a číselné údaje   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

Polypyrrole one-dimensional nanostructures (nanotubes, nanobelts and nanofibers) were prepared using three various dyes (Methyl Orange, Methylene Blue and Eriochrome Black T). Their high electrical conductivity (from 17.1 to 60.9 S cm-1), good thermal stability (in the range from 25 to 150 °C) and resistivity against ageing (half-time of electrical conductivity around 80 days and better) were used in preparation of lightweight and flexible composites with silicone for electromagnetic interference shielding in the C-band region (5.85-8.2 GHz). The nanostructures' morphology and chemical structure were characterized by scanning electron microscopy, Brunauer-Emmett-Teller specific surface measurement and attenuated total reflection Fourier-transform infrared spectroscopy. DC electrical conductivity was measured using the Van der Pauw method. Complex permittivity and AC electrical conductivity of respective silicone composites were calculated from the measured scattering parameters. The relationships between structure, electrical properties and shielding efficiency were studied. It was found that 2 mm-thick silicone composites of polypyrrole nanotubes and nanobelts shield almost 80% of incident radiation in the C-band at very low loading of conductive filler in the silicone (5% w/w). Resulting lightweight and flexible polypyrrole composites exhibit promising properties for shielding of electromagnetic interference in sensitive biological and electronic systems.

• MeSH
• azosloučeniny chemie   MeSH
• elektromagnetické záření * MeSH
• methylenová modř chemie   MeSH
• mikroskopie elektronová rastrovací MeSH
• nanostruktury chemie   účinky záření   ultrastruktura   MeSH
• nanotrubičky chemie   účinky záření   ultrastruktura   MeSH
• nanovlákna chemie   účinky záření   MeSH
• polymery chemie   účinky záření   MeSH
• pyrroly chemie   účinky záření   MeSH
• silikony chemie   účinky záření   MeSH
• Publikační typ
• časopisecké články MeSH

Selenium nanoparticle modified surfaces attract increasing attention in the field of tissue engineering. Selenium exhibits strong anticancer, antibacterial and anti-inflammatory properties and it maintains relatively low off-target cytotoxicity. In our paper, we present the fabrication, characterization and cytocompatibility of titanium oxide (TiO2) nanotube surface decorated with various surface densities of chemically synthesized selenium nanoparticles. To evaluate antibacterial and anti-cancer properties of such nanostructured surface, gram negative bacteria E. coli, cancerous osteoblast like MG-63 cells and non-cancerous fibroblast NIH/3T3 were cultured on designed surfaces. Our results suggested that selenium nanoparticles improved antibacterial properties of titanium dioxide nanotubes and confirmed the anticancer activity towards MG-63 cells, with increasing surface density of nanoparticles. Further, the selenium decorated TiO2 nanotubes suggested deteriorating effect on the cell adhesion and viability of non-cancerous NIH/3T3 cells. Thus, we demonstrated that selenium nanoparticles decorated TiO2 nanotubes synthesized using sodium selenite and glutathione can be used to control bacterial infections and prevent the growth of cancerous cells. However, the higher surface density of nanoparticles adsorbed on the surface was found to be cytotoxic for non-cancerous NIH/3T3 cells and thus it might complicate the integration of biomaterial into the host tissue. Therefore, an optimal surface density of selenium nanoparticles must be found to effectively kill bacteria and cancer cells, while remaining favorable for normal cells.

• MeSH
• antibakteriální látky chemie   farmakologie   MeSH
• buňky NIH 3T3 MeSH
• Escherichia coli účinky léků   MeSH
• infekce vyvolané Escherichia coli farmakoterapie   MeSH
• lidé MeSH
• myši MeSH
• nádorové buněčné linie MeSH
• nádory farmakoterapie   MeSH
• nanočástice * chemie   ultrastruktura   MeSH
• nanotrubičky * chemie   ultrastruktura   MeSH
• osteoblasty účinky léků   MeSH
• protinádorové látky chemie   farmakologie   MeSH
• selen chemie   farmakologie   MeSH
• titan chemie   farmakologie   MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• myši MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

Nanofibrous elastic material based on the blend of hydrophobic poly(ε-caprolactone) (PCL) and hydrophilic gelatin (Gel) reinforced with halloysite nanotubes (HNTs) was prepared by electrospinning process by respecting principles of "green chemistry" required for tissue engineering and drug delivery carriers. Three different kinds of HNTs with similar aspect ratio, but different length and inner diameter were examined to explain the effect of HNT concentration and geometry on a structure, morphology, chemical composition, mechanical properties and biocompatibility of nanostructured materials. Reinforcing effect of each type of HNTs has been confirmed up to 6 wt%. However, the highest improvement of mechanical properties was exhibited by addition just 0.5 wt% of HNTs. All HNT modified nanofibers have been confirmed as non-cytotoxic based on the interaction with mouse fibroblasts NIH-3T3 cells and therefore suitable for biomedical applications, e.g. as wound healing coverings with controlled drug delivery.

• MeSH
• buňky NIH 3T3 MeSH
• fibroblasty cytologie   MeSH
• hojení ran * MeSH
• hydrolýza MeSH
• jíl MeSH
• mechanický stres MeSH
• myši MeSH
• nanotrubičky chemie   ultrastruktura   MeSH
• nanovlákna chemie   ultrastruktura   MeSH
• polyestery chemie   MeSH
• proliferace buněk MeSH
• pružnost * MeSH
• silikáty hliníku chemie   MeSH
• skot MeSH
• spektrometrie rentgenová emisní MeSH
• spektroskopie infračervená s Fourierovou transformací MeSH
• viabilita buněk MeSH
• želatina chemie   MeSH
• zvířata MeSH
• Check Tag
• myši MeSH
• skot MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH

We developed membrane voltage nanosensors that are based on inorganic semiconductor nanoparticles. We provide here a feasibility study for their utilization. We use a rationally designed peptide to functionalize the nanosensors, imparting them with the ability to self-insert into a lipid membrane with a desired orientation. Once inserted, these nanosensors could sense membrane potential via the quantum confined Stark effect, with a single-particle sensitivity. With further improvements, these nanosensors could potentially be used for simultaneous recording of action potentials from multiple neurons in a large field of view over a long duration and for recording electrical signals on the nanoscale, such as across one synapse.

• MeSH
• biosenzitivní techniky metody   MeSH
• elektřina * MeSH
• HEK293 buňky MeSH
• kvantové tečky chemie   MeSH
• lidé MeSH
• membránové potenciály fyziologie   MeSH
• nanotrubičky ultrastruktura   MeSH
• povrchové vlastnosti MeSH
• studie proveditelnosti MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• Research Support, N.I.H., Extramural MeSH

The exceptionally high cellular uptake of gold nanorods (GNRs) bearing cationic surfactants makes them a promising tool for biomedical applications. Given the known specific toxic and stress effects of some preparations of cationic nanoparticles, the purpose of this study was to evaluate, in an in vitro and in vivo in mouse, the potential harmful effects of GNRs coated with (16-mercaptohexadecyl)trimethylammonium bromide (MTABGNRs). Interestingly, even after cellular accumulation of high amounts of MTABGNRs sufficient for induction of photothermal effect, no genotoxicity (even after longer-term accumulation), induction of autophagy, destabilization of lysosomes (dominant organelles of their cellular destination), alterations of actin cytoskeleton, or in cell migration could be detected in vitro. In vivo, after intravenous administration, the majority of GNRs accumulated in mouse spleen followed by lungs and liver. Microscopic examination of the blood and spleen showed that GNRs interacted with white blood cells (mononuclear and polymorphonuclear leukocytes) and thrombocytes, and were delivered to the spleen red pulp mainly as GNR-thrombocyte complexes. Importantly, no acute toxic effects of MTABGNRs administered as 10 or 50 μg of gold per mice, as well as no pathological changes after their high accumulation in the spleen were observed, indicating good tolerance of MTABGNRs by living systems.

• MeSH
• autofagie účinky léků   MeSH
• kvartérní amoniové sloučeniny metabolismus   MeSH
• lidé MeSH
• lyzozomy účinky léků   metabolismus   MeSH
• mezenchymální kmenové buňky cytologie   účinky léků   MeSH
• mikrofilamenta účinky léků   metabolismus   MeSH
• mutageny toxicita   MeSH
• myši inbrední C57BL MeSH
• nádorové buněčné linie MeSH
• nanotrubičky chemie   toxicita   ultrastruktura   MeSH
• podocyty účinky léků   metabolismus   MeSH
• pohyb buněk účinky léků   MeSH
• poškození DNA MeSH
• slezina účinky léků   patologie   MeSH
• sulfhydrylové sloučeniny metabolismus   MeSH
• tkáňová distribuce MeSH
• trombocyty účinky léků   patologie   ultrastruktura   MeSH
• zlato metabolismus   MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• mužské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH

In this work, we report for the first time on the use of melt spun glass-forming alloys - Ti75Zr10Si15 (TZS) and Ti60Zr10Si15Nb15 (TZSN) - as substrates for the growth of anodic oxide nanotube layers. Upon their anodization in ethylene glycol based electrolytes, highly ordered nanotube layers were achieved. In comparison to TiO2 nanotube layers grown on Ti foils, under the same conditions for reference, smaller diameter nanotubes (~116nm for TZS and ~90nm for TZSN) and shorter nanotubes (~11.5μm and ~6.5μm for TZS and TZSN, respectively) were obtained for both amorphous alloys. Furthermore, TEM and STEM studies, coupled with EDX analysis, revealed a double-wall structure of the as-grown amorphous oxide nanotubes with Ti species being enriched in the inner wall, and Si species in the outer wall, whereby Zr and Nb species were homogeneously distributed.

• MeSH
• elektrody MeSH
• křemík chemie   MeSH
• nanotrubičky chemie   ultrastruktura   MeSH
• oxidy chemie   MeSH
• sklo chemie   MeSH
• slitiny chemie   MeSH
• spektrometrie rentgenová emisní MeSH
• titan chemie   MeSH
• velikost částic MeSH
• zirkonium chemie   MeSH
• Publikační typ
• časopisecké články MeSH

This work describes the preparation of transparent TiO₂ nanotube (TNT) arrays on fluorine-doped tin oxide (FTO) substrates. An optimized electrolyte composition (0.2 mol dm-3NH₄F and 4 mol dm-3H₂O in ethylene glycol) was used for the anodization of Ti films with different thicknesses (from 100 to 1300 nm) sputtered on the FTO glass substrates. For Ti thicknesses 600 nm and higher, anodization resulted in the formation of TNT arrays with an outer nanotube diameter around 180 nm and a wall thickness around 45 nm, while for anodized Ti thicknesses of 100 nm, the produced nanotubes were not well defined. The transmittance in the visible region (λ = 500 nm) varied from 90% for the thinnest TNT array to 65% for the thickest TNT array. For the fabrication of transparent TNT arrays by anodization, the optimal Ti thickness on FTO was around 1000 nm. Such fabricated TNT arrays with a length of 2500 nm exhibit stable photocurrent densities in aqueous electrolytes (~300 µA cm-2at potential 0.5 V vs. Ag/AgCl). The stability of the photocurrent response and a sufficient transparency (≥65%) enables the use of transparent TNT arrays in photoelectrochemical applications when the illumination from the support/semiconductor interface is a necessary condition and the transmitted light can be used for another purpose (photocathode or photochemical reaction in the electrolyte).

• MeSH
• elektrody MeSH
• ethylenglykol chemie   MeSH
• fluor chemie   MeSH
• fluoridy chemie   MeSH
• fotochemické procesy MeSH
• kvartérní amoniové sloučeniny chemie   MeSH
• nanotechnologie metody   MeSH
• nanotrubičky chemie   ultrastruktura   MeSH
• sloučeniny cínu chemie   MeSH
• sluneční energie MeSH
• titan chemie   MeSH
• Publikační typ
• časopisecké články MeSH

Sterilization is the final surface treatment procedure of all implantable devices and is one of the key factors which have to be considered before implementation. Since different sterilization procedures for all implantable devices influence mechanical properties as well as biological response, the influence of different sterilization techniques on titanium nanotubes was studied. Commonly used sterilization techniques such as autoclaving, ultra-violet light sterilization, hydrogen peroxide plasma sterilization as well as the not so frequently used gaseous oxygen plasma sterilization were used. Three different nanotube diameters; 15 nm, 50 nm and 100 nm were employed to study the effects of various sterilization techniques. It was observed that autoclave sterilization resulted in destruction of nanotubular features on all three studied nanotube diameters, while UV-light and both kinds of plasma sterilization did not cause any significant morphological changes on the surfaces. Differences between the sterilization techniques employed influenced cytocompatibility, especially in the case of nanotubes with 100 nm diameter.

• MeSH
• biokompatibilní materiály chemie   MeSH
• buněčné linie MeSH
• design vybavení MeSH
• kyslík chemie   MeSH
• lidé MeSH
• nanotrubičky chemie   mikrobiologie   ultrastruktura   MeSH
• osteoblasty cytologie   MeSH
• peroxid vodíku chemie   MeSH
• plazmové plyny chemie   MeSH
• povrchové vlastnosti MeSH
• sterilizace přístrojové vybavení   metody   MeSH
• testování materiálů MeSH
• titan chemie   MeSH
• ultrafialové záření MeSH
• viabilita buněk MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH