Mid‐infrared spectroscopy and multivariate curve resolution for analyzing human adipose tissue triacylglycerols

The aim of this study was to evaluate use of infrared spectroscopy for measuring adipose tissue triacylglycerols (TAGs) with analysis by multivariate curve resolution (MCR). The mid‐infrared spectrum was measured with an attenuated total reflection accessory from a lipid droplet pressed from adipose tissue. The obtained spectra were characteristic of pure TAG spectra and water and protein contamination could be easily identified from specific spectral regions. MCR analysis of the olefinic (?C? H) stretch (3006 cm^?1), resolved the different contributions of monounsaturated (MUFA) and polyunsaturated (PUFA) double bonds. Similar MCR analysis of the trans (HC?CH? ) region (966 cm^?1), resolved the differing contributions of isolated trans isomers (transFA) and CLA. The PUFA double bond content of 16 subjects was negatively correlated with concentrations of serum total cholesterol R = ?0.498 (p = 0.050) and triacylglycerols R = ?0.609, (p = 0.016). The transFA content exhibited a negative, although non‐significant, correlation to high‐density lipoprotein (HDL)‐cholesterol (R = ?0.483, p = 0.068). The present study shows that MCR analysis of adipose tissue TAG infrared spectra can be used to estimate differences in the fatty acid (FA) profiles in population studies. Infrared spectroscopy in combination with MCR provides a robust method for assessing a FA profile of human adipose tissue. Practical applications: This study has highlighted the use of MCR to enhance the information obtained from infrared spectra. This new approach provides a robust method for assessing a FA profile of human adipose tissue lipids.