|
ИСТИНА |
Войти в систему Регистрация |
ИСТИНА ЦЭМИ РАН |
||
RAMAN DIAGNOSTICS OF CAROTENOIDS: EXPERIMENT AND DFT COMPUTATIONтезисы доклада
- Авторы: Prokhorov K.A., Novikov V.S., Kuznetsov S.M., Ustynyuk L.Yu, Darvin M.E., Lademann J., Sagitova E.A., Nikolaeva G.Yu
- Сборник: Cборник тезисов VII Троицкой конференции с международным участием "Медицинская физика (ТКМФ-7), Троицк, Россия, 19–21 октября 2020 г
- Тезисы
- Год издания: 2020
- Первая страница: 14
- Последняя страница: 15
- Аннотация: Raman spectroscopy, density functional theory (DFT) Carotenoids are extremely important substances for human organisms and skin physiology. They are involved in a number of complex biochemical processes and serve as antioxidants. Lack of carotenoids in a human organism could be an indication of development of a number of diseases or pathological states [1]. The common structural feature of all carotenoids is the presence of a polyene chain. Carotenoids diff er in the length of the polyene chain, the type of side and end groups, the isomeric states. Carotenoid molecules can contain two ionone rings, one, and no ionone rings at all. The isomeric composition of carotenoids greatly aff ects their biological activity, including the provitamin A activity, antioxidant properties and anticancer eff ects. Thus, the analysis of carotenoid content and isomeric states in biological tissues, food, drugs, and cosmetics is of great importance. Raman spectroscopy can provide non-invasive and non-destructive analysis of carotenoids in both biological tissues and plant species. Very important results were obtained in highly informative and reliable in vivo Raman analysis of carotenoids in human skin [2]. In this work we carried out experimental research of Raman spectra of neat ß-carotene and of carotenoids in various fruits and vegetables. Raman spectra of all the studied carotenoids contain two prominent Raman bands of conjugated polyenes. These bands correspond to the stretching vibrations of single C-C and double C=C bonds measured at ≈1155 and 1524 cm-1, respectively. Position of the band, related to the single C-C bond vibrations, noticeably diff ers for diff erent types of isomers. Resonant enhancement of these lines under excitation in the blue-green region makes it easy to analyze carotenoids at very small concentrations down to ≈ 0.05 μg/ml. To develop the capabilities of Raman spectroscopy in the analysis of the carotenoids, we applied the density functional theory (DFT) for modeling the structure and Raman spectra of these molecules. The DFT calculations confi rmed and expanded the experimental results. It was shown that the positions and intensities of the Raman bands related to the stretching vibrations of single and double C-C bonds depend on the length of polyene chain in the molecule, structure of the side and end groups, and type of the isomer. References 1. Lademann J., Patzelt A., Schanzer S. et al. // Skin Pharmacol. Physiol. 2011. V. 24. № 5. P. 269. 2. Darvin M.E., Meinke M.C., Sterry W., Lademann J. // J. Biomed. Opt. 2013. V. 18. № 6. 3. Art. № 061230.
- Добавил в систему: Устынюк Лейла Юрьевна