Determination of Sodium Fatty Acid in Soap Formulation Using Fourier Transform Infrared (FTIR) Spectroscopy and Multivariate Calibrations

Abstract

Fourier Transform Infrared (FTIR) spectroscopy using an attenuated total reflectance (ATR) accessory has been investigated as a method for the determination of sodium-fatty acid (sodium-FA) in soap formulations. Multivariate calibrations namely partial least squares regression (PLS) and principle component regression (PCR) were developed for the prediction of sodium-FA using spectral ranges on the basis of relevant IR absorption bands related to sodium-FA. The sodium-FA content in soap formulations was predicted accurately at wavenumbers of 1,570-1,550 cm -1 , which is specific for RCOONa ? vibration. The PLS method was found to be a consistently better predictor when both PLS and principal component regression (PCR) analyses were used for quantification of sodium-FA. Furthermore, FTIR spectroscopy can be an alternative technique to American oil Chemist Society methods which use a titrimetric technique because FTIR offers rapid, easy sample preparation and is friendly to the environment.

Improving the determination of moisture in edible oils by FTIR spectroscopy using acetonitrile extraction

“…The determination of moisture is no exception, and a variety of approaches have been taken to determine moisture in edible oils by FTIR spectroscopy, from simplistic to more sophisticated, the latter focusing more on the accurate determination of lower moisture levels and attempting to account for matrix effects. FTIR spectroscopy in conjunction with the attenuated total reflectance (ATR) technique was applied to the determination of moisture in crude palm oil (Che Man and Mighani, 2000), palm oil derived soaps (Rohman and Che Man, 2009), and olive oil (Cerretani et al, 2010). These applications involved the development of product-specific partial-least-squares (PLS) calibration models, requiring extensive calibration effort, while the inherently short pathlengths associated with ATR accessories limit the sensitivity of the methods.…”

Characterization and Performance Evaluation of Metakaolin-Based Geopolymer Foams Obtained by Adding Palm Olein as the Foam Stabilizer

“…Typical absorption bands corresponding to the stretching and bending vibration of H-O-H and O-H groups from free water and bound water are observed around 3445 and 1651 cm −1 [ 40 ], respectively. Three new absorption peaks around 2923, 2852, and 1564 cm −1 appear in the IR spectra of geopolymer foams with palm olein addition, corresponding to the stretching vibration of -CH 2 - and -COO − [ 41 ]. This reveals the existence of long-chain fatty acid salts in geopolymer foams.…”

Thermal, Structural and Morphology Studies of PEO-LICF3SO3-DBP-ZrO2 Nanocomposite Polymer Electrolytes

“…Characteristic frequencies of LiCF3SO3 were assigned at 1227.05 cm -1 (vs (CF3)), 1191.44 cm -1 (vas(CF3)), 1039.37 cm -1 (vs(SO3)) and 640.31 cm -1 (δs(CF3)) [19]. The presence of water can be identified by observing a broad peak at 3400 -3600 cm -1 , which is the characteristic of -OH stretching of hydrogen bonding [20]. This was observed at a frequency of 3528.47 cm -1 for the LiCF3SO3 spectrum.…”