• Publikační typ
• abstrakt z konference MeSH

Na perfluoralkylové látky (PFAS) je v posledních letech soustředěná pozornost širší veřejnosti, protože to jsou látky znečišťující životní prostředí. Jsou to např. kyselina perfluoroktanová a perfluoroktansulfonová. Tyto látky vznikají průmyslovou aktivitou člověka především při výrobě polymerů nebo nepřilnavých povrchů. Odpadní vodou nebo i jinými cestami se mohou dostat do prostředí, a tak kontaminovat zdroje pitné vody nebo potraviny. Jejich působení na organismy a lidské zdraví je rozsáhle studováno a jejich přítomnosti v organismu je připisován vliv na mnohé zdravotní komplikace, dokonce i některé druhy rakoviny. Z toho důvodu byly stanoveny přípustné limity PFAS v pitné vodě a jejich regulací se zabývají mnohé státní orgány a mezinárodní organizace. Aktuálním standardem v detekci PFAS jsou chromatografické metody. V současnosti jsou zkoumány i nové metody detekce především optickou a elektrochemickou cestou. Jejich příklady jsou v textu detailněji popsány a diskutovány.

Perfluoroalkyl substances (PFAS) have gained wider public attention in recent years as environmental pollutants which include perfluorooctanoic acid and perfluorooctanesulfonic acid. These substances are produced by industry, mainly during the manufacture of polymers or non-stick surfaces. They can enter the environment through waste water or other routes and contaminate drinking water sources or food. Their effects on organisms and human health have been extensively studied and their presence in the body has been attributed to many health complications including cancer. For this reason, limits for PFAS in drinking water have been established and their regulation is being addressed by many governments and international organisations. Chromatographic methods are the current standard for PFAS detection, but new detection methods, mainly optical and electrochemical, are currently being investigated. Examples of these are described in more detail in the text.

• MeSH
• elektrochemické techniky klasifikace   metody   MeSH
• fluorescenční spektrometrie metody   MeSH
• fluorokarbony * analýza   chemie   škodlivé účinky   toxicita   MeSH
• hodnocení vlivů na zdraví metody   MeSH
• impedanční spektroskopie metody   MeSH
• kontaminace potravin MeSH
• látky znečišťující životní prostředí analýza   klasifikace   škodlivé účinky   MeSH
• lidé MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• práce podpořená grantem MeSH
• přehledy MeSH

Two approaches to polymer surface nanostructuring by laser beam are discussed: (i) exposure of surface to a polarized excimer laser beam and (ii) scanning of doped polymer surface by a semiconductor laser. The effect of laser fluence, the angle of incident laser beam and its wavelength on the nanostructure formation is described. Nanostructured polymers are used as substrates for deposition of Au nanolayers and biocompatibility studies. The properties of deposited Au nanolayers are significantly influenced by surface structure and chemical nature of the used substrate. Polymer films doped with porphyrin were irradiated with laser and simultaneously mechanically scanned. By combination of these two techniques a regular periodic pattern was formed. The structural properties depend on scanning rate and laser intensity. Nanostructured polymer surfaces are promising substrates in electronics, optics and tissue engineering.

• Klíčová slova
• laserový svazek, interakce,
• MeSH
• biokompatibilní materiály MeSH
• biopolymery terapeutické užití   MeSH
• buněčné kultury MeSH
• lasery využití   MeSH
• nanostruktury MeSH
• nanotechnologie MeSH
• polymery terapeutické užití   MeSH
• povrchové vlastnosti MeSH
• tkáňové inženýrství MeSH
• tkáňové podpůrné struktury MeSH
• Publikační typ
• práce podpořená grantem MeSH

The creation of an antibacterial material with triggerable properties enables us to avoid the overuse or misuse of antibacterial substances and, thus, prevent the emergence of resistant bacterial strains. As a potential light-activated antibacterial material, polymethylmethacrylate (PMMA) nanofibers doped with silver nanoparticles (AgNPs) and meso-tetraphenylporphyrin (TPP) were prepared by electrospinning. TPP was chosen as an effectively reactive oxygen species (ROS) producer. Antibacterial tests on Staphylococcus epidermidis (S. epidermidis) and Enterococcus faecalis (E. faecalis) showed the excellent light-triggerable antibacterial activity of the doped materials. Upon light irradiation at the wavelength corresponding to the TPP absorption peak (405nm), antibacterial activity dramatically increased, mostly due to the release of AgNPs from the polymer matrix. Furthermore, under prolonged light irradiation, the AgNPs/TPP/PMMA nanofibers, displayed enhanced longevity and photothermal stability. Thus, our results suggest that the proposed material is a promising option for the photodynamic inactivation of bacteria.

• MeSH
• antibakteriální látky chemie   MeSH
• Enterococcus faecalis růst a vývoj   MeSH
• kovové nanočástice chemie   ultrastruktura   MeSH
• nanovlákna chemie   ultrastruktura   MeSH
• polymethylmethakrylát chemie   MeSH
• Staphylococcus epidermidis růst a vývoj   MeSH
• stříbro chemie   MeSH
• Publikační typ
• časopisecké články MeSH

A dual-mode functional chip for chiral sensing based on mobile phone wettability measurements and portable surface-enhanced Raman spectroscopy (SERS) is reported. The plasmon-active regular gold grating surface was covalently grafted with chiral recognition moieties, l- or d-enantiomers of tartaric acid, making stereoselective discrimination of chiral amines possible. Chiral sensing of amines includes two modes of analysis, performed subsequently on the one chip surface with portable instruments (mobile phone equipped with a camera and developed application (app) Dropangle and a portable Raman spectrometer). First, the wettability changes, caused by enantioselective entrapping of chiral amines, are monitored and analyzed via our mobile phone app, allowing detection of the optical configuration and concentration of enantiomers with 1 order of magnitude accuracy. Second, SERS measurement on the same chip provides information about the chemical structure of entrapped amines and allows calculation of the enantiomeric excess with great accuracy. The applicability of the developed chip is demonstrated on a variety of chiral amines, including tyrosine, cysteine, dopamine (DOPA), and dextromethorphan in analytical solutions and in commercially available DOPA-containing drug. Moreover, we demonstrate that the chips could be regenerated and used repeatedly for at least five cycles.

• MeSH
• aminy analýza   chemie   MeSH
• chytrý telefon MeSH
• mobilní aplikace MeSH
• Ramanova spektroskopie přístrojové vybavení   metody   MeSH
• smáčivost MeSH
• stereoizomerie MeSH
• tartaráty chemie   MeSH
• zlato chemie   MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

Smart antimicrobial materials with on-demand drug release are highly desired for biomedical applications. Herein, we report about temperature-responsive poly(N-isopropylacrylamide) (PNIPAM) nanospheres doped with crystal violet (CV) and incorporated into the poly-l-lactide (PLLA) nanofibers. The nanofibers were prepared by electrospinning, using different initial polymers ratios. The morphology of the nanofibers and polymers distribution in the nanofibers were characterized by scanning electron microscopy (SEM) and atomic force microscopy (AFM). The interaction between PNIPAM and PLLA in the nanofibers was studied by Fourier transform infrared spectroscopy (FTIR) and its effect on the PNIPAM phase transition was also investigated. It was shown that by the changing of the environmental temperature across the lower critical solution temperature (LCST) of PNIPAM, the switchable wettability and controlled CV release can be achieved. The temperature-dependent release kinetics of CV from polymer nanofibers was investigated by ultraviolet-visible spectroscopy (UV-Vis). The temperature-responsive release of antibacterial CV was also tested for triggering of antibacterial activity, which was examined on Staphylococcus epidermidis (S. epidermidis) and Escherichia coli (E. coli). Thus, the proposed material is promising value for controllable drug-release.

• MeSH
• akrylové pryskyřice chemie   MeSH
• antiinfekční látky lokální chemie   metabolismus   farmakologie   MeSH
• Escherichia coli účinky léků   MeSH
• genciánová violeť chemie   metabolismus   farmakologie   MeSH
• mikroskopie atomárních sil MeSH
• mikroskopie elektronová rastrovací MeSH
• nanovlákna chemie   MeSH
• nosiče léků chemie   MeSH
• polyestery chemie   MeSH
• smáčivost MeSH
• spektroskopie infračervená s Fourierovou transformací MeSH
• Staphylococcus epidermidis účinky léků   MeSH
• teplota MeSH
• uvolňování léčiv MeSH
• změna skupenství MeSH
• Publikační typ
• časopisecké články MeSH

Navrhovaný projekt zahrnuje vytvoření nového systému z optických vláken pro lokální monitorování, snímání a modifikaci substrátu. Materiál pro zavedení do živé tkáně (in-vivo experiment) bude navržen biologicky rozložitelný a biologicky kompatibilní. Tím se zabrání riziku spojenému s použitím konvenčního vlákna z křemenného skla. Pro základ výzkumu bude použita polymerní směs a polymerní sítě. Následně bude vyvinut materiál pro konstrukci optického vlákna a jeho spojení s laserovými zdroji a detektory. Povrch optických vláken bude vyvíjen s funkcionalizovanou citlivou vrstvou pro zavedení možnosti pro chemické analýzy in-vivo. Bezpečnost a biokompatibilita vyvinutého systému bude testována v preklinických podmínkách. Projekt kombinuje odborníky z různých oblastí výzkumu, jsou kompletně pokryty všechny fáze projektu.; Proposed project involves development of novel optical system for fiber-optic based local monitoring, sensing and treatment. First, the material, to be inserted into the living mass (in-vivo experiment) will be biodegradable and biocompatible. This prevents the risk associated with traditional silica fiber. As the background, polymer blends and interpenetrating polymer networks will be used. Then, developed material will be used for construction of optical fiber and its connection with laser sources and detectors. Additionally, surface of optical fibers will be functionalized by susceptible layer for introducing the possibility for chemical analysis in-vivo. The safety and biocompatibility of developed system will be tested in a preclinical settings. Project combine specialists from different field of research and completely covered all stage of preparation of above mentioned system.

• MeSH
• biokompatibilní materiály MeSH
• intravitální mikroskopie MeSH
• molekulární sondy MeSH
• optická vlákna MeSH
• polymery MeSH
• testování materiálů MeSH
• vstřebatelné implantáty MeSH

• Konspekt
• Patologie. Klinická medicína
• NLK Obory
• biomedicínské inženýrství
• technika lékařská, zdravotnický materiál a protetika
• NLK Publikační typ
• závěrečné zprávy o řešení grantu AZV MZ ČR

Modification of polymer substrates can essentially change the properties of material and thereby it allows their usage in attractive fields of material research. Laser treatment can be successfully applied for change in physico-chemical surface properties and/or for selective change of surface morphology with pattern construction. Three major applications of laser induced structures were described, cytocompatibility control, application as anti-bacterial substrate and plasmonic-based detection system. The construction of a second generation antibacterials using the synergic effect of either nanopatterning of polymers by application of a laser or noble metals deposition and consequent modification of nanostructures was presented.

• MeSH
• antiinfekční látky chemie   farmakologie   MeSH
• biosenzitivní techniky přístrojové vybavení   MeSH
• buněčná adheze MeSH
• buněčné kultury přístrojové vybavení   metody   MeSH
• DNA analýza   MeSH
• lasery MeSH
• lipidy analýza   MeSH
• nádory patologie   MeSH
• nanostruktury chemie   MeSH
• nanotechnologie metody   MeSH
• polymery chemie   MeSH
• povrchové vlastnosti MeSH
• Ramanova spektroskopie přístrojové vybavení   metody   MeSH
• tkáňové inženýrství metody   MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• přehledy MeSH

The chiral recognition of organic compounds is of vital importance in the field of pharmacology and medicine. Unfortunately, the common analytical routes used in this field are significantly restricted by time spent and equipment demands. In this work, we propose an unprecedented alternative, aimed at enantiomer discrimination and estimation of their concentrations in an uncomplicated and instantaneous manner. The proposed approach is based on the creation of an optical fiber probe with two pronounced plasmonic bands attributed to gold and silver. The gold or silver surfaces were grafted with moieties, able to enunciating entrap chiral amines from solution, resulting in a wavelength shift corresponding to each plasmonic metal. As a model compound of chiral amine, we chose the DOPA, also taking in mind its high medical relevancy. For chiral detection, the optical fiber probe was simply immersed in an analytical solution of DOPA, and the selective shift of gold or silver plasmon bands was observed in the reflected light depending on DOPA chirality. The observed shifts depend on the concentration of DOPA enantiomers. In the case of a racemic mixture, the shifts of both plasmonic bands emerge, making possible the simultaneous determination of enantiomer concentrations and their ratio. The analytical cycle takes several minutes and requires very simple laboratory equipment.

• MeSH
• optická vlákna normy   MeSH
• povrchová plasmonová rezonance metody   MeSH
• technologie optických vláken metody   MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

Nowadays, functionalization of the plasmon-supported nanostructured surface is considered as a powerful tool for tumour cell recognition. In this study, the SERS on a surface plasmon polariton-supported gold grating functionalized with folic acid was used to demonstrate an unpretentious recognition of melanoma-associated fibroblasts. Using cultivation media conditioned by different cells, we were able to detect reproducible differences in the secretome of melanoma-associated and normal control fibroblasts. The homogeneous distribution of plasmon energy along the grating surface was proved to provide excellent SERS signal reproducibility, while, to increase the affinity of (bio)molecules to SERS substrate, folic acid molecules were covalently grafted to the gold gratings. As proof of concept, fibroblasts were cultured in vitro, and culture media from the normal and tumour-associated lines were collected and analysed with our proposed SERS substrates. Identifying individual peaks of the Raman spectra as well as comparing their relative intensities, we showed that the proposed functional SERS platform can recognise the melanoma-associated cells without the need for further statistical spectral evaluation directly. We also demonstrated that the SERS chip created provided a stable SERS signal over a period of 90 days without loss of sensitivity. Graphical abstract.

• MeSH
• fibroblasty asociované s nádorem chemie   patologie   MeSH
• kovové nanočástice chemie   MeSH
• kultivované buňky MeSH
• kyselina listová chemie   MeSH
• lidé MeSH
• melanom chemie   patologie   MeSH
• nádorové buňky kultivované MeSH
• povrchové vlastnosti MeSH
• Ramanova spektroskopie metody   MeSH
• zlato chemie   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH