Analysis of Human Oral Mucosa Ex Vivo for Fatty Acid Compositions Using Fourier‐transform Infrared Spectroscopy

Abstract

The purpose of this research was to develop an infrared spectroscopic technique (Fourier transform infrared spectroscopy with attenuated total reflectance system; FTIR-ATR) for non-invasive measurement of saturated and unsaturated fatty acid compositions in human oral mucosa obtained from three nationalities; Iranian, Vietnamese, and Indonesian. The histogram patterns of fatty acid compositions for three nationalities suggest that the pattern of unsaturated fatty acids were quite different, although the distribution profiles of fatty acid to lipid ratios in FTIR-ATR has a similar normal pattern with small difference in skewness and mode. The second derivative infrared spectra of the mucosal tissues in the wavenumber regions from 1,600 to 1,760 cm(-1) and 2,800 to 3,050 cm(-1) were analyzed with partial least squares (PLS) multivariate regression analysis method. With this analysis method we compared predicted values with the measured values of ten categorized fatty acid compositions, i.e., a(saturated C17 or lower), b(C16:1 + C17:1), c(C18:0), d(C18:1), e(C18:2), f(saturated C20 or longer), g(C20:3 + C20:4), h(C22:1 + C24:1), i(C22:6), j(gammaC18:3). Almost all fatty acid compositions of oral mucosa were well predicted with differences between predicted and measured values within +/-5% of total, however, errors were relatively larger in minor components such as C22:6 than major components.

Characterizing variability in in vivo Raman spectroscopic properties of different anatomical sites of normal tissue in the oral cavity

“…hydroxyapatite (677418), collagen type I (C9879), DNA (P4522), oleic acid (O1008) and keratin] were found to be the most significant Raman active scatters that could efficiently characterize the morphology and histochemistry of oral tissues. For instance, DNA represents nucleic acids within the cell nucleus, whereas oleic acid represents typical lipid signals [38] ; keratin generally resembles characteristic protein signals (e.g. intense phenylalanine, amide I, δ(CH 2 ) and amide III associated bands) and is present in oral keratinized epithelia, whereas collagen represents a substantial fraction of the extracellular matrix.…”

FTIR imaging and ATR-FT-Far-IR synchrotron spectroscopy of pig ear skin

“…1B from an area rich in CH (but without the 1750 cm −1 band) is revealing a mixture of free fatty acids and ceramides. The presence and content of free fatty acids is determined from the C=O band at 1725 cm −1 [31]. The presence and content of ceramides is determined from the amide I and II bands at 1675 and 1555 cm −1 and from the relationship between the amide bands and the CH-stretching vibration bands of which the CH stretching vibration bands are the strongest ones in spectra of ceramides [20] and the amid bands are the strongest ones in spectra of skin proteins [1].…”

Desenvolvimento de um método para determinação de ácidos graxos em meios biológicos utilizando a espectroscopia no infravermelho com transformada de Fourier

“…Esta técnica espectroscópica é muito utilizada no estudo da conformação, identificação e interação com outras moléculas (COLTHUP; DALY; WIBERLEY, 1964). Nos últimos anos a espectroscopia no infravermelho vem sendo muito utilizada para fins analíticos, e está sendo muito utilizada na determinação de ácidos graxos livres em diferentes meios: extratos brutos de óleo de soja (LANSER et al, 1991), ácidos graxos em tecido adiposo de porco (RIPOCHE; GUILLARD, 2001;OLSEN et al, 2008), ácidos graxos trans em óleos comestíveis ( VAN DE VOORT et al, 2008;SHERAZI et al, 2009), ácidos graxos em mucosa oral (YOSHIDA et al, 2008) e na análise de lubrificantes ( VAN DE VOORT et al, 2008).…”