Characterization of Long-Chain Fatty Acids by Infrared Spectroscopy

Detection of Specific Lipids in Mycobacteria by Infrared Spectroscopy

“…With regard to the application of infrared spectroscopy to the identification and characterization of large molecules, one question that has to be kept in mind is what is the magnitude and type of chemical difference that can be detected within the range of spectrum examined and with the resolution commonly employed? One example 1960] of the type of chemical difference that can be detected by infrared spectroscopy is demonstrated in the work of Sinclair et al (1952) and Meikeljohn et al (1957), in which a relationship is shown between the number of methylene groups in long chain fatty acids and esters and a progression of bands in the region 7.5 to 8.5 ,. The latter authors have extended the study to include free fatty acids and soaps (odd and even numbers of carbon atoms) in the series from C2 to C36 and have shown that the number of bands in the progression series is directly related to the number of carbon atoms in the chain.…”

The Fatty Acids of Bacteria

“…Infrared spectroscopy. In recent years this technique has become one of the major tools of fatty acid analysis (104,148). The examination of infrared absorption spectra has three main applications: in determining the details of molecular structure of a compound, in detecting the presence of unidentified substances even in complex mixtures, and in identifying individual compounds by comparing their spectra with those of known compounds.…”

Attenuated Total Reflection Surface-Enhanced Infrared Absorption (ATR SEIRA) Spectroscopy for the Analysis of Fatty Acids on Silver Nanoparticles

“…The results obtained for both the position and carbon number of the methylene wagging vibration bands of silver nanoparticles were consistent with those previously reported. 38,39 It can be presumed that band progression was observed, in analogy with normal paraffin, 40 alcohol, 41 and glyceride, 42 as a result of interaction with the methylene wagging vibration mode, based on the orientation of the fatty acids on the silver nanoparticles.…”