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Tytuł:
Spektroskopia NIR - modelowanie kwantowo-mechaniczne widm jako narzędzie w badaniach podstawowych i wsparcie zastosowań analitycznych
NIR spectrometry - spectra simulation as a potent tool in basic research and analytical applications
Autorzy:
Beć, Krzysztof B.
Grabska, Justyna
Powiązania:
https://bibliotekanauki.pl/articles/27310036.pdf
Data publikacji:
2023
Wydawca:
Polskie Towarzystwo Chemiczne
Tematy:
modelowanie kwantowo-mechaniczne widm
spektroskopia absorpcyjna w zakresie bliskiej podczerwieni (NIR)
interpretacja widm
nadtony
pasma drgań kombinacyjnych
przypisania pasm
spectra simulation
near-infrared (NIR)
spectra interpretation
overtones
combination bands
band assignments
Opis:
Near-infrared (NIR) spectroscopy is a powerful technique that has been extensively used for the qualitative and quantitative analysis of a broad range of chemical compounds in various fields, such as pharmaceuticals, food, and environmental monitoring. However, the interpretation of NIR spectra is often challenging due to the complex line shape and overlapping signals that make it difficult to assign the bands to specific molecular vibrations. In recent years, significant advancements in theoretical methods have enabled the calculation of NIR spectra for a variety of molecules, paving the way for the integration of computational chemistry and NIR spectroscopy. This emerging field offers a wealth of opportunities to improve our understanding of the spectral features and to provide detailed molecular fingerprints that are essential for fundamental research and practical applications. Accurate simulation of NIR bands unlocks new potential in exploring the solvent effect or intermolecular interactions, in which cases interpreted overtones and combination bands provide unique information, complementary to that extracted from the fundamental bands observed in mid-infrared (MIR) region. In the area of applications, by reproducing the spectra of molecules with complex structures, theoretical calculations can provide new physical insights into the nature of the vibrational modes that contribute to the spectral signals. This knowledge can be used to improve the accuracy and reliability of chemometric models that are commonly used in quantitative analysis.
Źródło:
Wiadomości Chemiczne; 2023, 77, 7-8; 719--743
0043-5104
2300-0295
Pojawia się w:
Wiadomości Chemiczne
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Zastosowanie spektroskopii oscylacyjnej w zakresie nir do śledzenia modyfikacji konformacyjnych zachodzących w hydrofobowym obszarze modelowych dwuwarstw lipidowych
Application of nir range vibrational spectroskopy to follow the conformational modifications occuring in the hydrophobic region of model lipid bilayers
Autorzy:
Kuć, Marta
Cieślik-Boczula, Katarzyna
Rospenk, Maria
Powiązania:
https://bibliotekanauki.pl/articles/27310038.pdf
Data publikacji:
2023
Wydawca:
Polskie Towarzystwo Chemiczne
Tematy:
dwuwarstwa lipidowa
liposom
główne przejście fazowe
spektroskopia oscylacyjna w zakresie średniej podczerwieni (MIR)
spektroskopia oscylacyjna w zakresie bliskiej podczerwieni (NIR)
Analiza Składników Głównych (PCA)
lipid bilayer
liposome
main phase transition
Mid-infrared vibrational spectroscopy (MIR)
Near-infrared vibrational spectroscopy (NIR)
Principal Component Analysis (PCA)
Opis:
Biomembranes, which are the structural and functional basis of the cells of all living organisms, have been an extremely interesting research object for biology and chemistry scientists for years. The multitude of elements constituting the components of natural lipid membranes, however, is associated with interpretation difficulties regarding the nature of the processes taking place in them. A useful research object that is a model of bilamellar biosystems with a significantly simplified composition and at the same time retaining properties that can be a reference point in relation to natural membranes are lipid membranes in the form of one or several component liposomes. It is precisely such systems built of molecules of dipalmitoyl phosphatidylcholine (DPPC) or dipalmitoyl phosphatidylglycerol (DPPG), and analogous systems with the addition of cholesterol (Chol), that were the subject of research in this work. Near-infrared (NIR) vibrational spectroscopy provides a suitable method for the study of the hydrated samples. In most cases it can be alternatively adopted instead of commonly used mid-infrared (MIR) vibrational spectroscopy. This technique was applied for the first time to identify the spectral changes associated with the conformational changes in the hydrophobic region of model lipid bilayers. Trans/gauche isomerization of CH2 groups of lipid hydrocarbon chains is accompanied by characteristic changes in spectral parameters of both νas,s CH2 bands and their first overtones (2νas,s CH2). The heating of all types of analyzed liposomes results in main phase transition (Tm) accompanied by trans to gauche isomerization of CH2 groups of lipid hydrocarbon chains. The NIR-spectroscopy was able to describe in proper way (similar to MIR results) the character of Tm in studied bilayers.
Źródło:
Wiadomości Chemiczne; 2023, 77, 7-8; 647--686
0043-5104
2300-0295
Pojawia się w:
Wiadomości Chemiczne
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Przegląd zastosowań spektroskopii w zakresie bliskiej podczerwieni w analizie wilgotności śladowej w produktach leczniczych weterynaryjnych immunologicznych
Review of applications of near infrared spectroscopy in analysis of residual moisture in immunological veterinary medicinal products
Autorzy:
Bulenger, K.
Biernacki, B.
Krasucka, D. M.
Szumiło, J.
Cuvelier, B.
Powiązania:
https://bibliotekanauki.pl/articles/171718.pdf
Data publikacji:
2016
Wydawca:
Polskie Towarzystwo Chemiczne
Tematy:
spektroskopia NIR
bliska podczerwień
miareczkowanie Karla Fischera
model ilościowy
woda śladowa
oznaczanie
near infrared spectroscopy
NIRS
Karl Fischer titration
quantitative model
residual water determination
Opis:
However, the infrared radiation has been discovered more than 200 years ago, near-infrared spectroscopy (NIRS), as a useful method, was recognized in the 1960s. Currently, under the influence of technological development, quantitative and qualitative methods require short time and precision of measurements. NIRS has a growing recognition in the industry, particularly pharmaceutical where each component of the finished product has impact on the quality and safety of the product. Freeze-dried immunological veterinary medicinal products (IVMPs), despite high specificity, contain not too complicated matrices for analysis. Karl Fischer titration is routinely used as accurate and effective method to determine the water content in the IVMPs, but the use of near-infrared spectroscopy allows to avoid the adverse impact of environmental factors on the measurements. However, for NIRS, there is a need to create a calibration model which will be precise for high diversity of samples. The most important is the optimization of the model by eliminating the factors that might influence the measurement of water content. Quantification methods most frequently used are: MLR, PLS and PCR, which are preceded by the appropriate pretreatments (derivatives of Savitzky Golay).
Źródło:
Wiadomości Chemiczne; 2016, 70, 11-12; 747-759
0043-5104
2300-0295
Pojawia się w:
Wiadomości Chemiczne
Dostawca treści:
Biblioteka Nauki
Artykuł
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