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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:
Narzędzia budowania wiedzy o procesie wytwarzania produktu leczniczego w myśl koncepcji Quality by Design.
Process knowledge discovery tools in compliance with Quality by Design concept.
Autorzy:
Ronowicz, Joanna
Powiązania:
https://bibliotekanauki.pl/articles/762703.pdf
Data publikacji:
2019-12-29
Wydawca:
Polskie Towarzystwo Farmaceutyczne
Tematy:
zarządzanie jakością
chemometria
koncepcja Quality by Design
chemometrics
quality management
Quality by Design concept
Opis:
The significant change in the pharmaceutical quality approach (QbD concept, PAT strategy) and focusing on improving the quality of drug products by reducing variability in the manufacturing process force the use of effective tools to discover knowledge about the process and product. The Quality by Design concept is an essential part of the modern approach to pharmaceutical quality. Due to the current trend of being QbD compliant, the use of chemometrics in pharmaceutical sciences is increasing. This strategy can shorten a drug development phase and reduce the overall experimental work and costs. Moreover, continuous process monitoring requires the application of advanced, often non-invasive instrumental analytical techniques that generate a huge amount of process data. Their effective analysis and interpretation is possible thanks to chemometrics. The appropriate chemometric algorithms allow to detect cause-effect relations between the raw materials properties, process parameters and the drug product quality. The detected relations can be easily translated into accurate and rationally justified technological decisions, leading to manufacturing process optimization and consequently significant improvement of drug product quality. The effective building of process and product knowledge within the QbD concept is possible by means of non-invasive analytical methods generating process data sets which in-depth analysis and interpretation is possible with the use of the appropriate chemometric algorithms. The use of chemometric techniques enables better understanding of the effect of material attributes and process factors on the final drug product quality. Prognostic mathematical models can be generated to describe in detail the interrelations between excipients and the critical quality attribute of final formulation. This approach should be taken into consideration by industrial formulation scientists to support rational decision making at the drug product development stage.
Zmiana podejścia do problemu zapewnienia jakości w farmacji przemysłowej (koncepcja QbD, strategia PAT), ukierunkowanie na poprawę jakości produktu leczniczego poprzez redukcję zmienności w procesie wytwarzania wymusza użycie efektywnych narzędzi budowania wiedzy o procesie i produkcie. Ciągłe monitorowanie procesu wytwarzania wymaga zastosowania zaawansowanych, często nieinwazyjnych metod analizy instrumentalnej, które generują ogromną ilość danych procesowych. Ich efektywna analiza i interpretacja jest możliwa dzięki metodom chemometrycznym. Odpowiednie algorytmy chemometryczne pozwalają wykryć zależności przyczynowo-skutkowe między właściwościami użytych surowców, parametrami procesu a jakością produktu leczniczego. Wykryte zależności przekładają się na trafne i racjonalnie uzasadnione decyzje technologiczne, prowadzące do optymalizacji procesu wytwarzania oraz poprawy jakości produktu leczniczego. Efektywne budowanie wiedzy o procesie i produkcie w ramach koncepcji QbD jest możliwe przy użyciu nieinwazyjnych metod analizy instrumentalnej generujących dane procesowe, których dogłębna analiza i interpretacja jest możliwa z wykorzystaniem odpowiednich algorytmów chemometrycznych.
Źródło:
Farmacja Polska; 2019, 75, 11; 648-655
0014-8261
2544-8552
Pojawia się w:
Farmacja Polska
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Zastosowanie spektrometrii oscylacyjnej w analizie fitozwiązków i substancji odżywczych w produktach naturalnych i spożywczych
Applying vibrational spectroskopy in an analysis of phytochemicals and nutrients in natural and food products
Autorzy:
Mazurek, Sylwester
Szostak, Roman
Powiązania:
https://bibliotekanauki.pl/articles/27310034.pdf
Data publikacji:
2023
Wydawca:
Polskie Towarzystwo Chemiczne
Tematy:
spektroskopia oscylacyjna
chemometria
analiza jakościowa
analiza ilościowa
klasyfikacja
vibrational spectroscopy
chemometrics
qualitative analysis
quantitative analysis
classification
Opis:
The prevalence of lifestyle diseases and trends related to healthy eating contribute to the constant search for chemical compounds with specific biological activity. Studies are conducted on plants and substances of natural origin that have been used in medicine for millennia. Techniques of vibrational spectroscopy are an underrated group of methods enabling direct analysis of plant raw material and food in their native forms. The presented examples of Arabidopsis tissues, various species and hybrids of poplar and Cistus herb classification, as well as quantitative analyses of active compounds in plant material and pharmaceutical products and determination of physicochemical parameters of common food (i.e. milk, yoghurts, pasta and flour), demonstrate the possibility of using vibrational spectroscopy for comprehensive analysis of samples of natural origin. Typical measurement techniques and chemometric methods are briefly described in this paper. The scheme of quantitative analysis based on vibrational spectra is shown and the impact of selected experimental parameters on the accuracy of the obtained results is discussed. The imaging techniques used to analyse the changes in plant tissue structures caused by genetic mutations were also presented.
Źródło:
Wiadomości Chemiczne; 2023, 77, 7-8; 745--774
0043-5104
2300-0295
Pojawia się w:
Wiadomości Chemiczne
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:
Zastosowanie metod elektrochemicznych w bioanalityce : wybrane zagadnienia
Electrochemical methods in bioanalytics : selected aspects
Autorzy:
Ufnalska, I.
Wiloch, M. Z.
Wesoły, M.
Ćwik, P.
Zabadaj, M.
Ciosek, P.
Wawrzyniak, U. E.
Wróblewski, W.
Powiązania:
https://bibliotekanauki.pl/articles/171732.pdf
Data publikacji:
2015
Wydawca:
Polskie Towarzystwo Chemiczne
Tematy:
elektrochemia
elektroniczny język
chemometria
kompleksy peptydjony miedzi(II)
warstwy boroorganiczne
electrochemistry
electronic tongue
chemometrics
peptide-copper(II) complexes
boroorganic layers
Opis:
The cooperation of scientists specializing in different fields has given rise to the integration of previously distinct thematic areas and creation of new multidimensional disciplines as a result. Biochemistry, which has derived from the borderline of chemistry and biology, can be set as a good example. In this short review an insight into electrochemical studies, which are currently carried out in the Department of Microbioanalytics at the Faculty of Chemistry (Warsaw University of Technology), was presented. Three independent scientific pathways introducing electrochemical methods for biochemical and bioanalytical purposes can be distinguished among the ongoing researches. The first one embraces the design of the so-called electronic tongue – a system used for the qualitative and quantitative analysis of liquid samples of complex composition. In this work, potentiometric sensor arrays were applied to develop an electronic tongue system enabling the evaluation of the effectiveness of bitter taste masking of pharmaceuticals. The second scientific pathway involves voltammetric studies of the interactions of biologically active peptides with copper(II) ions. The interest was drawn to clarify and describe the role of β-amyloid and NSFRY copper(II) complexes, relevant to Alzheimer’s disease occurrence and cardiovascular system disorder respectively. Finally, boronic acids and their derivatives, exhibiting the affinity for molecules possessing 1,2 or 1,3-diol group in their structure, were used as selective molecular receptors in the third research project. The studies include the selection of the optimal method and conditions of the immobilization process, providing the most favorable receptor layer structure, and the determination of the performances of constructed electrochemical sensor towards particular bioanalytes.
Źródło:
Wiadomości Chemiczne; 2015, 69, 9-10; 931-946
0043-5104
2300-0295
Pojawia się w:
Wiadomości Chemiczne
Dostawca treści:
Biblioteka Nauki
Artykuł
Wyświetlanie 1-15 z 20

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