Analysis of human tear fluid by Fourier transform infrared spectroscopy

Abstract

The purpose of this research is to find some useful spectroscopic factors in human tear fluid contents to monitor diurnal changes of the physicochemical ocular conditions noninvasively. All tear fluid samples were collected with glass microcapillary tubes from both eyes of three donors and analyzed by Fourier transform infrared spectroscopy with attenuated total reflectance (FTIR-ATR). We measured the peak intensities at 2852, 1735, 1546, and 1242 cm(-1), and the peak intensity ratios among those peaks in the second derivative spectra. We found significant diurnal and individual variations in those peak intensities for tear fluid obtained from right and left eyes. Among these variations, we observed significant changes in tear samples between right and left eyes. In this case the peak intensity ratio between 1242 (phosphate ester) and 2852 cm(-1) (fatty acid methylene) of right eye tear fluid was increased in the afternoon (1600 to 1900 h), while that of left eye tear fluid did not change significantly. In the ratio between 1242 (phosphate ester) and 1546 cm(-1) (amide II), the difference was not observed between both eyes. We conclude that the difference in diurnal variations of biochemical constituents between right and left eye tear fluids could be monitored noninvasively and nondestructively by FTIR technique and this method could be useful in the future for tear diagnoses.

Human chemerin correlation in gingival crevicular fluid and tear fluid as markers of inflammation in chronic periodontitis and type‐2 diabetes mellitus

“…The numerous studies mentioned above and the fact that GCF and tear fluid contain large amounts of constituents such as proteins, lipids, and active biomolecules, [20][21][22][23][24][25][26][27] suggest that they are derived from the systemic circulation, and this could be the reason for increased levels of chemerin in GCF and tear fluid in inflammatory conditions such as CP and CP with type-2 diabetes.…”

“…Tear fluid is an aqueous layer on the ocular surface, and has many functions such as lubrication and nourishment . Tear fluid is secreted throughout the day at a volume of about 1–3 mL and has been used as a diagnostic fluid due to the presence of various inflammatory and anti‐inflammatory markers in many ocular diseases .…”

“…20,21 Tear fluid is an aqueous layer on the ocular surface, and has many functions such as lubrication and nourishment. 22,23 Tear fluid is secreted throughout the day at a volume of about 1-3 mL and has been used as a diagnostic fluid due to the presence of various inflammatory and anti-inflammatory markers in many ocular diseases. [24][25][26][27] Apart from ocular diseases various studies have been performed with positive results for detection of glucose levels in tear fluid in diabetic subjects.…”

Analysis of fatty acid compositions of human tissues using Fourier‐transform infrared spectroscopy

“…The histogram patterns of fatty acid compositions of oral mucosa for three nationalities suggest that the patterns of unsaturated fatty acids were quite different, even though the distribution profiles of total fatty acid to protein ratios ([2850 cm -1 (1). It is also true for the ratio [2850 cm -1 ]/[1540 cm -1 ].…”

Multiplexing Determination of Cancer-Associated Biomarkers by Surface-Enhanced Raman Scattering Using Ordered Gold Nanohoneycomb Arrays

“…Only when anti-CEA and anti-AFP are successfully modified on the substrate, it could produce the peaks of C = O, N-H and C-N in FT-IR spectrum simultaneously. As shown in Figure 5, the peak at 1645 cm -1 belonged to C = O stretching vibrations of amide I [43], the peak at 1546 cm -1 belonged to N-H stretching vibrations of amide II [44,45], the peak at 1219 cm -1 belonged to C-N stretching vibrations [46]. It was obvious that amide bonds were formed, which meant that the antibodies were modified on ordered gold nanohoneycomb arrays with success.…”