A comparison of the biochemical composition of saliva and the intensity of absorption bands on the IR spectra of samples obtained during the day with an interval of 3 hours is given. It is shown that the IR spectra of samples obtained in the daytime and at night are significantly different. Thus, in the daytime, the intensity of bands corresponding to sugars and amino acid residues increases, but the intensity of absorption of lipids and free amino groups decreases. At the same time in the daytime, the pH and salivation rate are statistically significantly higher, however, the protein content and the coefficients of Ca / P and Na / K are lower. The calculation of the Spearman correlation coefficients confirmed the correlation between protein content in saliva and the intensity of absorption bands corresponding to amino acid residues and free amino groups. Thus, IR spectroscopy can be used to detect diurnal changes in the composition of biological fluids, in particular saliva.
saliva, infrared spectroscopy, biochemical composition, daily dynamics
1. Gordecov A.S. Infrakrasnaya spektroskopiya biologicheskih zhidkostey i tkaney. Sovremennye tehnologii v medicine, 2010, № 1, s. 84-98. [Gordetsov A.S. Infrared spectroscopy of biological fluids and tissues. Sovremennyye tekhnologii v meditsine, 2010, vol. 1, pp. 84-98. (In Russ.)]
2. Orphanou C.-M. The detection and discrimination of human body fluids using ATR FT-IR spectroscopy. Forensic Science International, 2015, vol. 252, pp. 10-16.
3. Zubareva G.M., Mikin V.M., Bordina G.E., Belyaeva I.A., Lopina N.P., Zubarev S.M., Kargapolov A.V. Infrakrasnaya spektrometriya v izuchenii rotovoy zhidkosti dlya diagnosticheskih celey. Stomatologiya, 2009, № 5, s. 7-10. [Zubareva G.M., Mikin V.M., Bordina G.Ye., Belyayeva I.A., Lopina N.P., Zubarev S.M., Kargapolov A.V. Infrared spectrometry in the study of oral fluid for diagnostic purposes. Stomatologiya, 2009, vol. 5, pp. 7-10. (In Russ.)]
4. Seredin P., Goloshchapov D., Kashkarov V., Ippolitov Y., Bambery K. The investigations of changes in mineral- organic and carbon-phosphate ratios in the mixed saliva by synchrotron infrared spectroscopy. Results in Physics, 2016, vol. 6, pp. 315-321.
5. Aubin S., Kupers R., Ptito M., Jennum P. Melatonin and cortisol profiles in the absence of light perception. Behavioural Brain Research, 2017, vol. 317, pp. 515-521.
6. Rodrigues L.M., Magrini T.D., Lima C.F., Scholz J., da Silva Martinho H., Almeida J.D. Effect of smoking cessation in saliva compounds by FTIR spectroscopy. Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy, 2017, vol. 174, pp. 124-129.
7. Inoue H., Ono K., Masuda W., Inagaki T., Yokota M., Inenaga K. Rheological properties of human saliva and salivary mucins. J. Oral Biosciences, 2008, vol. 50, no. 2, pp. 134-141.
8. Ferguson D.B., Botchway C.A. A comparison of circadian variation in the flow rate and composition of stimulated human parotid, submandibular and whole salivas from the same individuals. Archives of oral biology, 1980, vol. 25, pp. 559-568.
9. Dawes C. Circadian rhythms in the flow rate and composition of unstimulated and stimulated human submandibular saliva. J Physiol, 1975, vol. 244, pp. 535-548.
