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    Wyświetlanie 1-14 z 14
    Tytuł:
    Chemometric evaluation of concentrations of trace elements in intervertebral disc tissue in patient with degenerative disc disease
    Autorzy:
    Kubaszewski, Łukasz
    Zioła-Frankowska, Anetta
    Gasik, Zuzanna
    Frankowski, Marcin
    Dąbrowski, Mikołaj
    Molisak, Bartłomiej
    Kaczmarczyk, Jacek
    Gasik, Robert
    Powiązania:
    https://bibliotekanauki.pl/articles/987050.pdf
    Data publikacji:
    2017
    Wydawca:
    Instytut Medycyny Wsi
    Tematy:
    intervertebral disk
    degeneration
    trace elements
    chemometrics
    Opis:
    Background. The work is designed to uncover the pattern of mutual relation among trace elements and epidemiological data in the degenerated intervertebral disk tissue in humans. Hitherto the reason of the degenerative process is not fully understood. Trace elements are the basic components of the biological compound related both its metabolism as well as environmental exposure. The relation pattern among elements occurs gives new perspective in solving the cause of the disease. Methods. We have analysed trace elements content in the 30 intervertebral disc from 22 patients with degenerative disc disease. The concentrations of Al, Cu, Cd, Mo, Ni and Pb were determined with Atomic Absorption Spectrometry. To analyse the multidimentional relation between trace element concentration and epidemiological data the chemometric analysis was applied. Results. The similarity have been shown in occurrence of following pairs: Cd-Mo as well as Mg-Zn. The second pair was correlated with Pb concentration. Pb levels are observed to be competitive to Cu concentration. Cd concentration was related to Zn and Mg deficiency. No single but rather cluster of epidemiological data show observable influence on the TE tissue variance. Zn and Cu was related to the male sex. Operation with orthopedic implants were related to combined Al, Mo and Zn concentration. Conclusions. This is the first chemometric analysis of trace elements in disk tissue. It shows multidimentional relations that are missed by the classical statistic. The analysis shows significant relation. The nature of the relations is the basis for further metabolic and environmental research.
    Źródło:
    Annals of Agricultural and Environmental Medicine; 2017, 24, 4
    1232-1966
    Pojawia się w:
    Annals of Agricultural and Environmental Medicine
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Bromatological, analytical and chemometric assessment of animal and plant foods based on mineral composition
    Autorzy:
    Szefer, Piotr
    Grembecka, Małgorzata
    Powiązania:
    https://bibliotekanauki.pl/articles/2203256.pdf
    Data publikacji:
    2022-05-31
    Wydawca:
    Gdański Uniwersytet Medyczny
    Tematy:
    Assessment of food quality
    Analytics
    Chemometrics
    Bromatology
    Opis:
    There are several examples of numerous applications of analytical and multivariate techniques useful in investigations of varied assortment of food products. The successful use of chemometrics in study of food such as meat and its products, fish, seafood, milk and dairy products, honey, cereal products, oils, oilseeds and nuts, vegetables, fruits, mushrooms, tea, coffee, confectionary products, mineral waters and alcoholic beverages deserves attention. RDA indicated exceeded its normative values for Se, Cu, Mn, Fe and Cr in some groups of animal food and Cr, Mn, P and Fe in some assortment of plant food. Based on PTWI values for Pb, Cd and Hg, there is no threat to human health resulting from the consumption of the investigated food products. It is concluded that the proper use of analytical and chemometric tools is useful for assessing nutritive and health quality of animal and plant foods. They play an important role in quality control, and their classification in view of geographical origin, confection and degree of environmental pollution. Both, instrumental and multivariate techniques would be useable in differentiating unprocessed and technologically processed food as well as detecting fraud to preserve the brand name of the original product. The aim of this study is to give an overview of the crucial issues associated with the implementation of chemometrics in food research and development.
    Źródło:
    European Journal of Translational and Clinical Medicine; 2022, 5, 1; 77-106
    2657-3148
    2657-3156
    Pojawia się w:
    European Journal of Translational and Clinical Medicine
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Chemometrics as a tool for plant - inscet ecological studies
    Autorzy:
    Szafranek, J
    Nawrot, J.
    Szafranek, B.
    Malinski, E.
    Powiązania:
    https://bibliotekanauki.pl/articles/65215.pdf
    Data publikacji:
    2001
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    terpene
    pine needle
    sesquiterpene
    ant
    chemometrics
    insect
    plant
    Opis:
    The process of plant selection by insects is mediated by repellents and attractants. Several compounds may be involved in this interaction. Thus intraspecific variation of the compounds concentration play an important role in the herbivory. The best tool for the characteristic of this variation is chemometrics. The strategy of the analysis with the use of literature data on terpenes and sesquiterpenes variations in Pinus caribaea needles in relation to Atta laevigata herbivory is exemplified herein. Simple cluster analysis and principal components analysis were used for the data study. Two factors were found to be sufficient to describe total variation in more than 90%. Factor 1 is responsible for repellent properties. From factor loading, the relevant chemical compounds were identified.
    Wiele różnych substancji chemicznych zawartych w roślinach wpływa na zachowanie owadów, pełniąc funkcje repelentów lub atraktantów. Często nie pojedyncze związki, lecz ich mieszaniny o określonym składzie są aktywne semiochemicznie. Zmienność składu lotnych roślinnych substancji semiochemiczych można oceniać metodami chemometrycznymi w celu znajdywania składników istotnych w ekologicznej interakcji. Przeprowadzono pełną analizę chemometryczną danych literaturowych dotyczących zmian składu terpenów i seskwiterpenów z igieł sosny Pinus caribaea w odniesieniu do żerowania mrówek Atta laevigata. Do klasyfikacji danych zastosowano metodę analizy wiązkowej i metodę głównych składników. Dla opisu ponad 90% zmienności składu wystarczyło zastosować dwa faktory opisujące dane dotyczące drzew defoliowanych i niedefoliowanych. Metodą analizy chemometrycznej z ładunków faktorów zidentyfikowano związki chemiczne istotne w oddziaływaniach ekologicznych.
    Źródło:
    Journal of Plant Protection Research; 2001, 41, 4
    1427-4345
    Pojawia się w:
    Journal of Plant Protection Research
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Ultrasound-assisted emulsification–microextraction and spectrophotometric determination of cobalt, nickel and copper after optimization based on Box-Behnken design and chemometrics methods
    Autorzy:
    Doroudi, Z.
    Niazi, A.
    Powiązania:
    https://bibliotekanauki.pl/articles/778452.pdf
    Data publikacji:
    2018
    Wydawca:
    Zachodniopomorski Uniwersytet Technologiczny w Szczecinie. Wydawnictwo Uczelniane ZUT w Szczecinie
    Tematy:
    ultrasound-assisted emulsification–microextraction
    chemometrics
    cobalt
    nickel
    copper
    Opis:
    A fast, simple, and economical method for extraction, preconcentration and determination of cobalt, nickel and copper as their 1-(2-pyridilazo) 2-naphthol (PAN) complexes based on ultrasound-assisted emulsification–microextraction (USAEME) and multivariate calibration of spectrophotometric data is presented. Various parameters affecting the extraction efficiency were optimized both with univariate and Box–Behnken design. The resolution of ternary mixtures of these metallic ions was accomplished by using partial least-squares regression (PLS), orthogonal signal correction-partial least-squares regression (OSC-PLS), and orthogonal signal correction-genetic algorithmspartial least-squares regression (OSC-GA-PLS). Under the optimum conditions, the calibration graphs were linear in the range of 2.0–150.0, 2.0–120.0 and 2.0–150.0 ng mL−1  for Co2+ , Ni2+ , and Cu2+ , respectively, with a limit of detection of 0.14 (Co2+ ), 0.13 (Ni2+ ) and 0.14 ng mL−1  (Cu2+ ) and the relative standard deviation was <2.5%. The method was successfully applied to the simultaneous determination of these cations in different samples.
    Źródło:
    Polish Journal of Chemical Technology; 2018, 20, 1; 21-28
    1509-8117
    1899-4741
    Pojawia się w:
    Polish Journal of Chemical Technology
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Measurement data processing in spectrophotometric analysers of food. Review paper
    Autorzy:
    Morawski, R. Z.
    Powiązania:
    https://bibliotekanauki.pl/articles/221182.pdf
    Data publikacji:
    2012
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    spectrophotometry
    chemometrics
    spectral data processing
    food analysis
    wine analysis
    Opis:
    Spectrometry, especially spectrophotometry, is getting more and more often the method of choice not only in laboratory analysis of (bio)chemical substances, but also in the off-laboratory identification and testing of physical properties of various products, in particular - of various organic mixtures including food products and ingredients. Specialised spectrophotometers, called spectrophotometric analysers, are designed for such applications. This paper is on the state of the art in the domain of data processing in spectrophotometric analysers of food (including beverages). The following issues are covered: methodological background of food analysis, physical and metrological principles of spectrophotometry, the role of measurement data processing in spectrophotometry. General considerations are illustrated with examples, predominantly related to wine and olive oil analysis.
    Źródło:
    Metrology and Measurement Systems; 2012, 19, 4; 623-652
    0860-8229
    Pojawia się w:
    Metrology and Measurement Systems
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Assessment of poultry eggs freshness using FTIR spectroscopy combined with HCA and PCA methods
    Autorzy:
    Michalczyk, E.
    Kurczab, R.
    Powiązania:
    https://bibliotekanauki.pl/articles/93132.pdf
    Data publikacji:
    2018
    Wydawca:
    Państwowa Wyższa Szkoła Zawodowa w Tarnowie
    Tematy:
    egg freshness
    FTIR spectroscopy
    chemometrics
    świeżość jaja
    spektroskopia FTIR
    chemometria
    Opis:
    The main aim of this study was to investigate the use of Attenuated Total Reflection Fourier Transform Infrared Spectroscopy (ATR FTIR) and selected chemometric methods to classify eggs in terms of the laying hen farming method, as well as to identify changes in the individual egg compositions during storage. In total, 50 eggs were used for the study; 10 eggs per classes: 0, 1, 2, 3 and rural. Eggs were stored by 29 days period, which was divided on the 10 measuring days in which one egg from each class was tested by recording two FTIR spectra for the shell, albumen and egg yolk. The chemometric analysis, including Hierarchical Cluster Analysis (HCA) and the Principal Component Analysis (PCA), was performed based on the recorded FTIR spectra. Changes in chemical composition during the experiment in individual egg elements were analyzed. Furthermore, by analyzing the graphs (HCA and PCA) obtained by the chemometric analysis, it was noted that the largest changes in the chemical composition of eggs occurred in the shell and yolk, while in the albumen it was less insignificant. The chemometric analysis of the recorded spectra also showed that combination of chemometric methods and FTIR spectroscopy can potentially be used to develop a non-destructive method for classifying eggs in terms of the hen culture method and to monitor of their freshness.
    Źródło:
    Science, Technology and Innovation; 2018, 2, 1; 7-12
    2544-9125
    Pojawia się w:
    Science, Technology and Innovation
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Comparison of five SVD-based algorithms for calibration of spectrophotometric analyzers
    Autorzy:
    Wagner, J.
    Morawski, R. Z.
    Miękina, A.
    Powiązania:
    https://bibliotekanauki.pl/articles/220564.pdf
    Data publikacji:
    2014
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    spectrophotometry
    chemometrics
    singular value decomposition
    regularisation
    food analysis
    edible oils analysis
    Opis:
    Spectrophotometry is an analytical technique of increasing importance for the food industry, applied i.a. in the quantitative assessment of the composition of mixtures. Since the absorbance data acquired by means of a spectrophotometer are highly correlated, the problem of calibration of a spectrophotometric analyzer is, as a rule, numerically ill-conditioned, and advanced data-processing methods must be frequently applied to attain an acceptable level of measurement uncertainty. This paper contains a description of four algorithms for calibration of spectrophotometric analyzers, based on the singular value decomposition (SVD) of matrices, as well as the results of their comparison - in terms of measurement uncertainty and computational complexity - with a reference algorithm based on the estimator of ordinary least squares. The comparison is carried out using an extensive collection of semi-synthetic data representative of trinary mixtures of edible oils. The results of that comparison show the superiority of an algorithm of calibration based on the truncated SVD combined with a signal-to-noise ratio used as a criterion for the selection of regularisation parameters - with respect to other SVD-based algorithms of calibration.
    Źródło:
    Metrology and Measurement Systems; 2014, 21, 2; 191-204
    0860-8229
    Pojawia się w:
    Metrology and Measurement Systems
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Using chemometrics to identify water quality in Daya Bay, China
    Autorzy:
    Wu, M.-L.
    Wang, Y.-S.
    Sun, C.-C.
    Wang, H.
    Lou, Z.-P.
    Dong, J.-D.
    Powiązania:
    https://bibliotekanauki.pl/articles/49096.pdf
    Data publikacji:
    2009
    Wydawca:
    Polska Akademia Nauk. Instytut Oceanologii PAN
    Tematy:
    robust principal component analysis
    water quality
    chemometrics
    China
    cluster analysis
    Daya Bay
    Opis:
    In this paper, chemometric approaches based on cluster analysis, classical and robust principal component analysis were employed to identify water quality in Daya Bay (DYB), China. The results show that these approaches divided water quality in DYB into two groups: stations S3, S8, S10 and S11 belong to cluster A, which lie in Dapeng Cove, Aotou Harbor and the north-eastern part of DYB, where water quality is related mainly to anthropogenic activities. The other stations belong to cluster B, which lie in the southern, central and eastern parts of DYB, where the quality is related mainly to water exchange with the South China Sea. Cluster analysis yields good results as a first exploratory method for evaluating spatial difference, but it fails to demonstrate the relationship between variables and environmental quality on the one hand and the untreated data on the other. However, with the aid of suitable chemometric approaches, the relationship between samples or variables can be investigated. Classical and robust principal component analysis can provide a visual aid for identifying the water environment in DYB, and then extracting specific information about relationships between variables and spatial variation trends in water quality.
    Źródło:
    Oceanologia; 2009, 51, 2; 217-232
    0078-3234
    Pojawia się w:
    Oceanologia
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    UV-Vis spectroscopic detection coupled with chemometrics for the measurement of mixed organic acids in water samples enriched by radial electric focusing solid phase extraction
    Autorzy:
    Guo, Y.
    Liu, X.
    Liu, J.
    Bian, X.
    Zhang, Q.
    Pan, J.
    Wan, D.
    Powiązania:
    https://bibliotekanauki.pl/articles/221808.pdf
    Data publikacji:
    2018
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    chemometrics
    UV-Vis spectrophotometer
    radial electric focusing solid phase extraction
    mixed organic acids
    Opis:
    Due to the difficulty of detecting traces of organic acid mixture in an aqueous sample and the complexity of resolving UV-Vis spectra effectively, a combinatory method based on a self-made radical electric focusing solid phase extraction (REFSPE) device, UV-Vis detection and partial least squares (PLS) calculation is proposed here. In this study, REFSPE was used to enhance the extraction process of analytes between the aqueous phase and the membrane phase to enrich the trace of mixed organic acid efficiently. Then, the analytes, which were eluted from the adsorption film by ethanol with the assistance of an ultrasonic cleaning machine, were detected with UV-Vis spectrophotometry. After that, the PLS method was introduced to solve the problem of overlapping peaks in UV-Vis spectra of mixed substances and to quantify each compound. The linearly dependent coefficients between the predicted value of the model and the actual concentration of the sample were all higher than 0.99. The limit values of detection for benzoic acid, phthalic acid and p-toluene sulfonic acid were found at 9.9 μg/L, 12.2 μg/L and 13.8 μg/L with the relative recovery values between 84.8% and 117.9%. The RSD (n = 20) values of each component are 1.17%, 1.11% and 0.86%, respectively. Therefore, the proposed combined method can determine traces of complex materials in an aqueous sample efficiently and has wonderful potential applications.
    Źródło:
    Metrology and Measurement Systems; 2018, 25, 2; 317-329
    0860-8229
    Pojawia się w:
    Metrology and Measurement Systems
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Basic multivariate statistical methods for environmental monitoring data mining: introductory course for master students
    Autorzy:
    Simeonov, Vasil
    Powiązania:
    https://bibliotekanauki.pl/articles/1430146.pdf
    Data publikacji:
    2020
    Wydawca:
    Towarzystwo Chemii i Inżynierii Ekologicznej
    Tematy:
    chemometrics
    environmetrics
    exploratory data analysis
    EDA
    master students course
    chemometria
    środowisko
    eksploracyjna analiza danych
    kurs magisterski
    Opis:
    The present introductory course of lectures summarizes the principles and algorithms of several widely used multivariate statistical methods: cluster analysis, principal components analysis, principal components regression, N-way principal components analysis, partial least squares regression and self-organizing maps with respect to their possible application in intelligent analysis, classification, modelling and interpretation to environmental monitoring data. The target group of possible users is master program students (environmental chemistry, analytical chemistry, environmental modelling and risk assessment etc.).
    Źródło:
    Chemistry-Didactics-Ecology-Metrology; 2020, 25, 1-2; 35-56
    2084-4506
    Pojawia się w:
    Chemistry-Didactics-Ecology-Metrology
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Classification of Different-Sized Aerosol Monitoring Data
    Klasyfikacja danych monitoringowych frakcji aerozolu o różnych rozmiarach cząstek
    Autorzy:
    Tsakovski, S.
    Simeonov, V.
    Powiązania:
    https://bibliotekanauki.pl/articles/388252.pdf
    Data publikacji:
    2011
    Wydawca:
    Towarzystwo Chemii i Inżynierii Ekologicznej
    Tematy:
    chemometria
    klasyfikacja
    mapy samoorganizujące się
    frakcja aerozolowa
    chemometrics
    classification
    self-organizing maps
    aerosol fraction
    seasonal sampling
    Opis:
    The present study deals with the application of self-organizing maps (SOM) of Kohonen for the classification of aerosol monitoring data sets from two sampling points (Arnoldstein and Unterloibach) located close to the border between Austria and Slovenia. The goal of the chemometric data treatment was to find some specific patterns in the classification maps for five different aerosol fractions collected in four different seasons of the year. The results obtained indicated a distinct separation of the ultrafine particles (PM 0.01–PM 0.4) from the other fractions which underlines their specific effect on human health. Seasonal separation but only between summer and winter sampling is also observed.
    Przedstawiono wyniki badań monitoringowych próbek aerozolu atmosferycznego pobranych z dwóch punktów pomiarowych (Arnoldstein i Unterloibach) z pobliża granicy między Austrią i Słowenią. Dane zinterpretowano z wykorzystaniem samoorganizujących się map (SOM) Kohonena. Celem chemometrycznej interpretacji danych było znalezienie charakterystycznych struktur na mapach klasyfikacji dla pięciu różnych frakcji aerozoli, zebranych w czterech różnych porach roku. Uzyskane wyniki wskazują na wyraźne oddzielenie najdrobniejszych cząstek (PM 0,01 – PM 0,4) od innych frakcji, co wskazuje na ich specyficzne działanie na zdrowie człowieka. Obserwuje się również zmiany sezonowe, ale tylko między próbkami pobranymi latem i zimą.
    Źródło:
    Ecological Chemistry and Engineering. A; 2011, 18, 2; 275-288
    1898-6188
    2084-4530
    Pojawia się w:
    Ecological Chemistry and Engineering. A
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Discrimination of Selected Cold-Pressed and Refined Oils by Untargeted Profiling of Phase Transition Curves of Differential Scanning Calorimetry
    Autorzy:
    Islam, Mahbuba
    Magdalena, Montowska
    Emilia, Fornal
    Jolanta, Tomaszewska-Gras
    Powiązania:
    https://bibliotekanauki.pl/articles/16538550.pdf
    Data publikacji:
    2023-08-02
    Wydawca:
    Instytut Rozrodu Zwierząt i Badań Żywności Polskiej Akademii Nauk w Olsztynie
    Tematy:
    authentication
    plant oils
    chemometrics
    multivariate data analysis
    melting profiles
    orthogonal partial least squares-discriminant analysis
    differential scanning calorimetry
    Opis:
    The authenticity assessment of edible oils is crucial to reassure consumers of product compliance. In this study, a new approach was taken to combining untargeted profiling by using differential scanning calorimetry (DSC) with chemometric methods in order to distinguish cold-pressed oils (flaxseed, camelina, hempseed) from refined oils (rapeseed, sunflower, soybean). The whole spectrum of DSC melting profiles was considered as a fingerprint of each oil. Flaxseed and hempseed oils exhibited four endothermic peaks, while three peaks with one exothermic event were detected for camelina seed oil. In the case of refined oils, two endothermic peaks were detected for rapeseed oil, three for sunflower oil and four for soybean oil. Thermodynamic parameters, such as peak temperature, peak heat flow and enthalpy, differed for each type of oil. Principal component analysis (PCA) and orthogonal partial least squares-discriminant analysis (OPLS-DA) were used for processing data consisting of the whole spectrum of heat flow variables of melting phase transition. PCA demonstrated a clear separation between refined and cold-pressed oils as well as six individual oils. The OPLS-DA showed a distinct classification in six classes according to the types of oils. High OPLS-DA coefficients including R2X(cum)=0.971, R2(cum)=0.916 and Q2X(cum)=0.887 indicated good fitness of the model for oil discrimination. Variables influence on projection (VIP) plot indicated the most significant variables of the heat flow values detected at temperatures around −29°C, −32°C, −14°C, −10°C, −24°C and −41°C for the differentiation of oils. The study ultimately demonstrated great potential of the untargeted approach of using the whole melting DSC profile with chemometrics for the discrimination of cold-pressed and refined oils.
    Źródło:
    Polish Journal of Food and Nutrition Sciences; 2023, 73, 3; 224-232
    1230-0322
    2083-6007
    Pojawia się w:
    Polish Journal of Food and Nutrition Sciences
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Approximation of phenol concentration using novel hybrid computational intelligence methods
    Autorzy:
    Pławiak, P.
    Tadeusiewicz, R.
    Powiązania:
    https://bibliotekanauki.pl/articles/907935.pdf
    Data publikacji:
    2014
    Wydawca:
    Uniwersytet Zielonogórski. Oficyna Wydawnicza
    Tematy:
    soft computing
    neural network
    genetic algorithm
    fuzzy system
    evolutionary neural system
    pattern recognition
    chemometrics
    przetwarzanie miękkie
    sieć neuronowa
    algorytm genetyczny
    system rozmyty
    rozpoznawanie obrazu
    chemometria
    Opis:
    This paper presents two innovative evolutionary-neural systems based on feed-forward and recurrent neural networks used for quantitative analysis. These systems have been applied for approximation of phenol concentration. Their performance was compared against the conventional methods of artificial intelligence (artificial neural networks, fuzzy logic and genetic algorithms). The proposed systems are a combination of data preprocessing methods, genetic algorithms and the Levenberg–Marquardt (LM) algorithm used for learning feed forward and recurrent neural networks. The initial weights and biases of neural networks chosen by the use of a genetic algorithm are then tuned with an LM algorithm. The evaluation is made on the basis of accuracy and complexity criteria. The main advantage of proposed systems is the elimination of random selection of the network weights and biases, resulting in increased efficiency of the systems.
    Źródło:
    International Journal of Applied Mathematics and Computer Science; 2014, 24, 1; 165-181
    1641-876X
    2083-8492
    Pojawia się w:
    International Journal of Applied Mathematics and Computer Science
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Spectrophotometric study of interaction between selected bile acids and cyclodextrins
    Badanie spektrofotometryczne oddziaływania wybranych kwasów żółciowych z cyklodekstrynami w różnych temperaturach
    Autorzy:
    Zarzycki, P. K.
    Baran, M. J.
    Harasimiuk, F. B.
    Powiązania:
    https://bibliotekanauki.pl/articles/158419.pdf
    Data publikacji:
    2010
    Wydawca:
    Stowarzyszenie Inżynierów i Techników Mechaników Polskich
    Tematy:
    kwasy żółciowe
    sterydy
    cyklodekstryny
    spektrofotometria UV-VIS
    chromatografia planarna
    mikro-TLC
    temperatura
    chemia supramolekularna
    oddziaływanie typu gość-gospodarz
    kompleksy inkluzyjne
    statystyka wielowariancyjna
    chemometria
    analiza czynników głównych
    bile acids
    steroids
    cyclodextrins
    UV-Vis spectrophotometry
    planar chromatography
    micro-TLC
    temperature
    supramolecular chemistry
    host-guest interactions
    inclusion complexes
    multivariate statistics
    chemometrics
    principal component analysis
    Opis:
    The main goal of present work was to explore the host-guest complex formation between selected bile acids (dehydrocholic, cholic, deoxycholic, taurodeoxycholic, glycodeoxycholic, glycocholic and chenodeoxycholic acid) and cyclodextrins (ß-cyclodextrin and its hydroxypropyl derivative) at sub-ambient and elevated temperature, using as a probe the phenolphthalein-cyclodextrin inclusion complex detected via UV-Vis spectrophotometry. In order to explore the general trends in the complexation ability of the bile acids by macrocycles investigated, the quantitative data set containing ?AU values was analyzed by principal component analysis.
    W pracy przedstawiono wyniki badań nad oddziaływaniem wybranych kwasów żółciowych (kwas dehydrocholowy, cholowy, deoksycholowy, taurodeoksycholowy, glikodeoksycholowy, glikocholowy oraz chenodeo-ksycholowy; rys. 1) z substancjami makrocyklicznymi (ß-cyklodekstryna i jej hydroksypropylowa pochodna) w różnych temperaturach (0 oraz 30oC), wykorzystując jako detektor kompleks inkluzyjny makrocykli z fenoloftaleiną (rys. 2 i 3). Z punktu widzenia chemii analitycznej i diagnostyki medycznej kwasy żółciowe są grupą związków trudnych w detekcji i analizie ilościowej. Zastosowanie kompleksów supramolekularnych typu gość-gospodarz, w których skład wchodzi substancja barwna np. fenoloftaleina, umożliwia zastosowanie spektroftometrii do detekcji kwasów żółciowych oraz badań ich oddziaływania ze związkami makrocyklicznymi. Jest to istotne z punktu widzenia zastosowań praktycznych np. analizy kwasów żółciowych w materiałach biologicznych rozdzielanych metodami chromatograficznymi. W prezentowanej pracy dane eksperymentalne (?AU) uzyskane za pomocą spektrofotometrii UV-Vis (rys. 4) były analizowane metodą PCA (Principal Component Analysis; rys. 5). Wyniki analizy wskazują na kluczową rolę temperatury oraz podstawnika przy węglu C12 szkieletu sterydów na siłę oddziaływania badanych kwasów żółciowych z cyklodekstrynami (rys. 6). Zaobserwowano, iż w warunkach mikrochromatografii planarnej jest bardzo trudno rozdzielić parę kwasów chenodeoksycholowy/ deoksycholowy (rys. 7). Uzyskane wyniki wskazują na możliwość poprawy rozdzielania chromatograficznego wybranych par kwasów zółciowych przy zastosowaniu faz ruchomych modyfikowanych cyklodekstrynami (rys. 8).
    Źródło:
    Pomiary Automatyka Kontrola; 2010, R. 56, nr 4, 4; 355-359
    0032-4140
    Pojawia się w:
    Pomiary Automatyka Kontrola
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
      Wyświetlanie 1-14 z 14

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