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
Here, we present a new family of hierarchical porous hybrid materials as an innovative tool for ultrasensitive and selective sensing of enantiomeric drugs in complex biosamples via chiral surface-enhanced Raman spectroscopy (SERS). Hierarchical porous hybrid films were prepared by the combination of mesoporous plasmonic Au films and microporous homochiral metal-organic frameworks (HMOFs). The proposed hierarchical porous substrates enable extremely low limit of detection values (10-12 M) for pseudoephedrine in undiluted blood plasma due to dual enhancement mechanisms (physical enhancement by the mesoporous Au nanostructures and chemical enhancement by HMOF), chemical recognition by HMOF, and a discriminant function for bio-samples containing large biomolecules, such as blood components. We demonstrate the effect of each component (mesoporous Au and microporous AlaZnCl (HMOF)) on the analytical performance for sensing. The growth of AlaZnCl leads to an increase in the SERS signal (by around 17 times), while the use of mesoporous Au leads to an increase in the signal (by up to 40%). In the presence of a complex biomatrix (blood serum or plasma), the hybrid hierarchical porous substrate provides control over the transport of the molecules inside the pores and prevents blood protein infiltration, provoking competition with existing plasmonic materials at the limit of detection and enantioselectivity in the presence of a multicomponent biomatrix.
The properties of materials at the nanoscale open up new methodologies for engineering prospective materials usable in high-end applications. The preparation of composite materials with a high content of an active component on their surface is one of the current challenges of materials engineering. This concept significantly increases the efficiency of heterogeneous processes moderated by the active component, typically in biological applications, catalysis, or drug delivery. Here we introduce a general approach, based on laser-induced optomechanical processing of silver colloids, for the preparation of polymer surfaces highly enriched with silver nanoparticles (AgNPs). As a result, the AgNPs are firmly immobilized in a thin surface layer without the use of any other chemical mediators. We have shown that our approach is applicable to a broad spectrum of polymer foils, regardless of whether they absorb laser light or not. However, if the laser radiation is absorbed, it is possible to transform smooth surface morphology of the polymer into a roughened one with a higher specific surface area. Analyses of the release of silver from the polymer surface together with antibacterial tests suggested that these materials could be suitable candidates in the fight against nosocomial infections and could inhibit the formation of biofilms with a long-term effect.
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.
Remote detection of hydrogen, without the utilization of electronic component or elevated temperature, is one of the hot topics in the hydrogen technology and safety. In this work, the design and realization of the optical fiber-based hydrogen sensor with unique characteristics are proposed. The proposed sensor is based on the gold-coated multimode fiber, providing the plasmon properties, decorated by the IRMOF-20 layer with high selectivity and affinity toward hydrogen. The IRMOF-20 layer was grown by a surface-assisted technique, and its formation and properties were studied using X-ray photoelectron spectroscopy, Raman, X-ray diffraction, and Brunauer-Emmett-Teller techniques. Simultaneous ellipsometry results indicate the apparent changes of the refractive index of the IRMOF-20 layer due to hydrogen sorption. As results, the presence of hydrogen led to the pronounced changes of plasmon band wavelength position as well as its intensity increase. The proposed hydrogen sensors were favorably distinguished by a high response/recovery rate, excellent selectivity toward the hydrogen, very low temperature dependency, functionality at room or lower temperature, insensitivity toward the humidity, and the presence of CO2, CO, or NO2. Additionally, the proposed hydrogen sensor showed good reversibility, reproducibility, and long-term stability.
Závěrečná zpráva o řešení grantu Agentury pro zdravotnický výzkum MZ ČR
Nestr.
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
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
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.
Optical fibers have recently attracted a noticeable interest for biomedical applications because they provide a minimally invasive method for in vivo sensing, imaging techniques, deep-tissue photodynamic therapy or optogenetics. The silica optical fibers are the most commonly used because they offer excellent optical properties, and they are readily available at a reasonable price. The fused silica is a biocompatible material, but it is not bioresorbable so it does not decompose in the body and the fibers must be ex-planted after in vivo use and their fragments can present a considerable risk to the patient when the fiber breaks. In contrast, optical fibers made of phosphate glasses can bring many benefits because such glasses exhibit good transparency in ultraviolet-visible and near-infrared regions, and their solubility in water can be tailored by changing the chemical composition. The bioresorbability and toxicity of phosphate glass-based optical fibers were tested in vivo on male laboratory rats for the first time. The fiber was spliced together with a standard graded-index multi-mode fiber pigtail and an optical probe for in vitro pH measurement was prepared by the immobilization of a fluorescent dye on the fiber tip by a sol-gel method to demonstrate applicability and compatibility of the fiber with common fiber optics.
- MeSH
- fosfáty chemie metabolismus MeSH
- koncentrace vodíkových iontů MeSH
- krysa rodu rattus MeSH
- optická vlákna * MeSH
- oxid křemičitý chemie MeSH
- potkani Wistar MeSH
- zvířata MeSH
- Check Tag
- krysa rodu rattus MeSH
- mužské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
The design of smart surfaces with externally triggerable water/oil wettability and adhesion represents one of the most up-to-date challenges in the field of material science. In this work, the intelligent surface with electrically triggerable wettability and water/oil adhesion is presented. As a basic material background exhibiting electric field (EF) sensitivity, the piezo-responsive polymethylmethacrylate/polyvinylidenefluoride polymer fibers were used. To expand the available range of water/oil contact angles (CAs) and adhesion, the fibers were grafted with hydrophilic or hydrophobic functional groups using diazonium chemistry. The fiber functionality was evaluated using the static CA and wettability hysteresis measurements (increasing/decreasing drop volume and tilting angles), drops adhesion/repellence and graphite self-cleaning test performed with and without the application of EF. It was found that the proposed method enables tuning the surface wettability in the superhydrophobic/superoleophobic-hydrophilic/oleophilic range and changing of surface properties from low adhesive to high adhesive for water and oil. More convincing results were achieved in the case of fiber surface modification by ADT-C8F17, which may result from a rearrangement of the grated -C6H4C8F17 functional group under the application of EF triggering. Moreover, the triggering which can be performed in the extremely fast way (the surface responds to the EF switching on/off in seconds) was found to be fully reversible. Finally, the additional tests indicate the satisfactory stability of created fiber-based coating against the mechanical treatment.
