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PL
Zastosowanie technologii MALDI i technik elektromigracyjnych w analizie mikrobiologicznej może stać się kamieniem milowym w diagnostyce i analizie zakażeń.
EN
The rapid growth in the production and use of nanomaterials is observed in recent years. Nanoparticles of titanium dioxide (TiO2NPs) are one of the most frequently used nanomaterials. Sunscreens, food additives, food contact materials and textiles are the major fields of current application of TiO2NPs. Due to increasing use of nanomaterials in daily life and thus increasing exposure to them, concerns have been raised about their safety. Likely routes of human exposure to released TiO2NPs as well as their health and environmental effects are presented in this paper. At present, our knowledge about the risk of nanomaterials is incomplete. However, it is known that toxicity of nanoparticles depends on their size, shape, crystal structure, surface morphology, surface area, charge, concentration and solubility (the possibility of dissolution into ionic forms). Therefore, it is necessary to use several complementary analytical techniques to fully characterize the NPs. Common approaches used for the characterization of nanomaterials include microscopy based techniques e.g. transmission electron microscopy (TEM), X-ray techniques e.g. X-ray diffraction (XRD), methods based on optical properties e.g. dynamic light scattering (DLS). Separation of nanoparticulate and ionic forms of metal can be accomplished using chromatographic techniques (such as high performance liquid chromatography (HPLC), size exclusion chromatography (SEC), hydrodynamic chromatography (HDC)) or capillary electrophoresis (CE). Size-resolved NPs and dissolved (ionic) fractions can be further characterized by on-line detectors, such as ICP MS. Recently, single particle inductively coupled plasma mass spectrometry (sp ICP MS) has been gaining increasing attention as a technique for detection, characterization, and quantification of nanoparticles. This technique provides information on individual particles, including particle size, number size distribution, particle number concentration and mass concentration. In addition, sp ICP MS can distinguish dissolved and nanoparticulate forms of an element. The fundamentals, advantages and limitations of this technique, as well as its application for the characterization and quantification of TiO2NPs in different matrices (consumer products, food and environmental samples) are reviewed in this paper.
PL
Omówiono czynniki wpływające na degradację termiczną materiałów polimerowych. Szczególną uwagę poświęcono zależności przebiegu procesów degradacyjnych w polimerach i właściwości otrzymywanych tworzyw od warunków przetwórstwa. Przedstawiono możliwości monitorowania lotnych produktów wydzielających się w procesach przetwórczych za pomocą zaawansowanych metod instrumentalnych, takich jak: chromatografia gazowa (GC), spektrometria masowa (MS) lub techniki łączone. Stwierdzono też, że zastosowanie standardowych analiz lotnych produktów rozkładu tworzyw polimerowych może być przydatne w planowaniu i optymalizacji warunków przetwórstwa.
EN
Part II of the literature review discusses various factors affecting the thermal degradation of polymeric materials. Particular attention was paid to the impact of processing conditions on the degradation processes in polymers and the properties of the materials obtained. The focus was on the ability to monitor products generated in plastic processing using advanced instrumental methods, such as gas chromatography (GC), mass spectrometry (MS) and combined techniques. The use of standard analyses of volatile polymer degradation products may be useful for planning and optimization of processing conditions.
EN
Selected examples of studies conducted by the research group from Laboratory of the Basic Aspect of Analytical Chemistry (Faculty of Chemistry, University of Warsaw), related to the investigation of chemical speciation with the use of coupled techniques were discussed in this work. The pioneering investigation was focused on the study of the speciation of mercury in fish tissues and in clinical samples. Then, the intensive researches were conducted towards understanding of the speciation of antimony and selenium in water, plants and clinical objects. Interestingly, the evaluation of the speciation of aluminium become a challenge in respect of the establishing of the reliable analytical procedure, and the use of flow injection for sample operation were explored in this case. The last but not least, the non – routine analytical procedure was developed in the case of zinc speciation in plant exposed to the harmful environmental conditions.
5
EN
The rapid growth in the commercial application of silver nanoparticles (AgNPs) will certainly increase the exposure to these metals among humans and in the environment. Nano-size silver particles have a broad spectrum of antimicrobial activity and therefore are incorporated into various materials, including medical textiles, which claim to prevent infection, as well as more common textiles, like anti-odour sportswear, underwear, socks and gloves. On the market there is also a variety of home consumer products claiming to contain nanosilver, for example disinfecting sprays (to disinfect hard surfaces, towels, sheets, and clothing), kitchen cutting boards, washing machines, refrigerators, dishwashers, pillows and mattresses, toothbrushes, toilet seats, water filters, and cosmetics. Nanosilver is added to food contact materials to preserve the packaged food for a particularly long period of time by inhibiting the growth of microbes. There is a number of in vitro studies showing cytotoxic effects and genotoxic DNA damaging capacity of AgNPs to a variety of mammalian cell types [24]. However, there are only a few in vivo studies on their genotoxicity. Likely routes of human exposure to released nanoparticles include inhalation, ingestion and dermal penetration. Evaluation of the health impact of AgNPs requires information on how readily and in what forms this substance can be released from the material. At present, the availability of such data is limited (Tab. 1). Size of metal-based nanoparticles is an important factor determining their physical and chemical properties as well as their bioavailability and toxicity. The methods used for the size characterisation of AgNPs in different matrices (consumer products, biological and environmental samples) (Tab. 2), as well as for speciation analysis of various forms of silver, namely AgNPs and silver ions, are reviewed in this paper. Off-line methods such as centrifugal ultrafiltration, (ultra)centrifugation, dialysis, and cloud point extraction are used in order to distinguish between nanoparticles and dissolved forms of silver. Field-flow fractionation (FFF) in different modes is used for nanoparticle size dependent separation [50]. Size-resolved AgNPs fractions are further characterised by on-line detectors, such as UV-Vis, ICP OES or ICP MS. ICP MS in single-particle detection mode is used for simultaneous determination of nanosilver and silver ions [38]. The application of capillary electrophoresis [40] and liquid chromatography [41, 42] for the separation of nano and ionic forms of silver is also discussed in this work.
6
Content available Analiza specjacyjna w badaniach środowiska
EN
The review article contains basic definitions of speciation and speciation analysis in various aspects of human activity. It also features new approaches in fractionation analysis, problems related to reference materials and the most frequently used methods.
PL
Specjacja chemiczna jest ważna w dziedzinie ochrony środowiska, w badaniach toksykologicznych i analitycznych, dlatego że toksyczność, dostępność i reaktywność pierwiastków śladowych zależą od postaci chemicznej, w jakiej pierwiastek występuje. W ramach analityki specjacyjnej można wyróżnić oznaczanie substancji wytwarzanych przez ludzi i przez nich emitowanych do środowiska, a także analizę związków naturalnych, które powstają w wyniku przemian biochemicznych w organizmach żywych lub w środowisku.
EN
Chemical speciation is important in the environmental protection area, toxicological and analytical research because the toxicity, availability and reactivity of trace elements depends on the chemical form in which the element is present. As part of the speciation analysis can be distinguished the determination of substances produced by humans and their emitted into the environment, and the analysis of natural compounds that are formed as a result of biochemical changes in living organisms or in the environment.
PL
W pracy przedstawiono rolę i znaczenie analizy specjacyjnej oraz technik łączonych we współczesnej analityce środowiskowej. Krótko omówiono najnowsze rozwiązania aparaturowe i metodyczne w tym zakresie oraz perspektywy rozwojowe analizy specjacyjnej w najbliższych latach.
EN
In article presents the role and importance of speciation analysis and combined techniques in contemporary environmental analytics. Briefly discusses the latest developments Appliance and methodical in this area and the development prospects of speciation analysis in the coming years.
PL
Oznaczanie niskich stężeń analitów, szczególnie w próbkach o obciążonej matrycy, wymaga stosowania złożonych i wyrafinowanych metod i technik analitycznych. Najnowsze trendy w tym zakresie dotyczą tzw. technik łączonych, w których metody separacyjne łączone są z różnymi metodami detekcji. Zasadniczą zaletą technik łączonych wykorzystywanych w analityce specjacyjnej jest możliwość jednoczesnego oznaczania różnych form tego samego pierwiastka, często istotnie różniących się właściwościami toksykologicznymi. Techniki łączone w analityce specjacyjnej znajdują coraz szersze zastosowanie m.in. w ochronie środowiska, biochemii, geologii, medycynie, farmacji czy kontroli jakości produktów żywnościowych.
EN
Determination of low concentrations of analytes, particularly in samples with loaded matrix requires the use of complex and sophisticated methods and analytical techniques. The main advantage of the combined techniques used in analytical speciation is simultaneous determination of different forms of the same element, often significantly different toxicological properties. Combined analytical techniques for speciation find wider application of such environmental protection, biochemistry, geology, medicine, pharmacy, and quality control of food products.
EN
Mercury is a global pollutant and is identified as a highly toxic element because of its accumulative and persistent character in the environment and living organisms. Therefore, routine monitoring and control of mercury are becoming increasingly important in natural environment. Several analytical techniques have been developed for the determination of mercury and cold vapor atomic absorption spectroscopy (CV-AAS) is the most widely used one. However, CV-AAS is not straightforwardly applicable to some environmental, clinical, or biological samples in view of low analyte content and matrix of the sample. Atomic fluorescence spectrometry (AFS) detection, especially coupled with the cold vapor (CV) technique, is becoming popular and replacing atomic absorption spectroscopy for mercury analysis due to its simple instrumentation, relatively low cost of operation, high sensitivity and selectivity and ultra low detection limits, which can be evidenced by its approval by the US Environmental Protection Agency for the analysis of mercury in uncontaminated water. Speciation analysis brings important information on the real toxicity and migration pathways of mercury. The need for this kind of information has stimulated development of analytical solutions allowing separation of mercury species such as sequential extraction procedures and hyphenated techniques. The paper presents perspectives of development and application of determinations of total mercury and mercury species in environmental samples by the atomic fluorescence spectroscopy method based on cold vapor generation (CV-AFS). The different sequential extraction procedures in estimation of mercury mobility and bioavailability were also critically reviewed. Ranges of published detection limits achievable for mercury species determination by using different hyphenated techniques are also given. High pressure liquid chromatography coupled to AFS has become a very important tool in determination of mercury species in environmental samples in last years. The paper presents the possibilities of current analytical methods available with use this technique.
PL
W pracy zaprezentowano etapy oznaczania indywidualnych form rtęci oraz techniki selektywnego rozdzielania. Przedstawiono i opisano układ analityczny technik łączonych powstały z połączenia techniki rozdzielania (HPLC) i selektywnego detektora (AFS). Prezentowany układ HPLC-CV-AFS pozwala na przeprowadzenie pełnej analizy specjacyjnej rtęci w systemach zarówno środowiskowych, jak i biologicznych.
EN
The paper presents particular steps of determination of chemical species of mercury, as well as selective separation techniques. It describes hyphenated technique of high performance liquid chromatography coupled with atomic fluorescence spectrometry. Presented HPLC-CV-AFS system is used for speciation analysis of mercury in biological and environmental samples.
EN
The article presents the hyphenated technique of high performance liquid chromatography and hydride generation atomic absorption spectrometry (HPLC-HG-AAS) in determination of antimony inorganic species: Sb(lII) and Sb(V) in ground water samples. While carrying separation of these forms on an anion-exchange column in a cliromatographic system and detection by means of hydride generation atomic absorption spectrometry method, the analytical signals of the determined forms were separated at the detection limits of 6.8 ng/cm' (peak high) or 2.7 ng/cm' (peak area) in the case of Sb(lll) and 4.8 ng/cm3 (peak high) or 3,2 ng/cm' (peak area) in the case of Sb(V) with RSD below 20% at the concentration of 25 ng/cm'. The hyphenated technique was applied for antimony determinations in polluted ground water.
PL
W artykule przedstawiono technikę łączoną wysokosprawnej chromatografii cieczowej z detekcją absorpcyjnej spektrometrii atomowej z generowaniem wodorków (HPLC-HG-AAS) w oznaczeniach specjacyjnych nieorganicznych form antymonu: Sb(III) i Sb(V) w próbkach wód. Prowadząc rozdzielanie form specjacyjnych na kolumnie jonowymiennej w układzie chromatograficznym i detekcję z użyciem absorpcyjnej spektrometrii atomowej z generowaniem wodorków uzyskano rozdzielenie sygnałów analitycznych oznaczanych form antymonu przy granicach wykrywalności 6,8 ng/cm3 (wysokość piku) lub 2,7 ng/cm1 (powierzchnia piku) Sb(III) i 4,8 ng/cm' (wysokość piku) lub 3,2 ng/cm' (powierzchnia piku) Sb(V) z RSD odpowiednio poniżej 20% dla stężenia 25 ng/cm'. Technikę łączoną zastosowano w oznaczeniach antymonu w zanieczyszczonych wodach podziemnych.
EN
Different strategies for mercury species analysis in environmental samples by liquid chroma-tography and different approaches to sampling and preservation of mercury species during their storage have been reviewed. Extraction techniques of mercury species from environmental samples, including possibilities of mercury preconcentration have been described. Separation mechanisms of mercury species by liquid chromatographic techniques, such as reverse phase and ion-pair chromatography have been discussed. Different techniques for sensitive and selective detection of mercury and detection limits achievable with hyphenated techniques have been also critically reviewed. .
PL
W pracy dokonano przeglądu i oceny zastosowań chromatografii cieczowej z różnymi układami detekcji do rozdzielania i oznaczania związków rtęci w próbkach przyrodniczych. Opisano metody pobierania próbek, ich przechowywania, a także metody wyodrębniania związków rtęci z matryc i ich zatężanie. Scharakteryzowano różne mechanizmy rozdzielania związków rtęci występujące w chromatografii cieczowej, m.in. w odwróconym układzie faz i przy tworzeniu par jonowych. Krytycznej ocenie poddano różne metody detekcji stosowane w chromatografii cieczowej oraz podano granice oznaczalności przy ich wykorzystaniu. Przedstawiono też granice oznaczalności dla innych technik łączonych, stosowanych w analizie specjacyjnej związków rtęci.
EN
The paper presents perspectives of development and application of determinations of arsenic, antimony and selenium by the methods based on hydride generation [1,2, 4-17]. This technique employed in spectrometric methods: absorption atomic spectrometry (AAS), atomic fluorescence (AFS), microwave (MIP) or inductively excited plasma (ICP) with emission or mass detection has become a very important tool in determination of environmental samples [3, 18]. The paper presents the possibilities of current analytical methods available with the use of this technique. First of all the detection limit can be decreased by in-situ preconcentration of volatile hydrides on the cell walls [19-36]. The possibility of speciation determinations based on the differences in the kinetics of hydride generation by different species present in the sample is discussed [79]. Speciation analysis brings important information on the real toxicity of migration pathways of the element studied [37-78]. The need for this kind of information has stimulated development of new analytical solutions allowing separation of species in the chromatographic system or capillary electrophoresis, with selective spectrometric methods ICPMS, AAS or AFS in combination with hydride generation used for detection [79-115]. The progress in the hydride generation technique is closely related with recent attempts at direct analyses of solid samples [120-123], without the need to convert them into liquids, which facilitates the analytical process and permits simultaneous or almost simultaneous determination of many elements [124-126].
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