Determination of lecithin and soybean oil in dietary supplements using partial least squares-Fourier transform infrared spectroscopy.
Lecithin and soybean oil in dietary supplements were determined by Fourier transform infrared spectrometry transmission measurements in dichloromethane in combination with a partial least squares (PLS) regression. Two different PLS models were developed, using 16 synthetic mixtures of analytes in dichloromethane, making measurements in the spectral range from 931.8 to 1252.3 cm(-1) for lecithin and from 911.4 to 1246.9 cm(-1) and 1695.3 to 1774.5 cm(-1) for soybean oil. Seven products from the Spanish market with lecithin concentrations between 21.1% and 99.1% and soybean oil concentrations between 0% and 37.2% were analyzed by the proposed method and the data was compared to a chromatographic reference procedure obtaining accurate results. For samples spiked with amounts between 50 and 250 mg of lecithin and soybean oil recovery percentages between 98.0% and 102.1% and between 93.6% and 102.0% with an average precision of 0.35% and 0.41% were achieved for lecithin and soybean oil, respectively. This method can be applied for the quality control of dietary supplements.
Kuligowski
J
J
Department of Analytical Chemistry, Universitat de València, Edificio Jeroni Muñoz, 50th Dr. Moliner, 46100 Burjassot, Spain.
Quintás
G
G
Garrigues
S
S
de la Guardia
M
M
D002138:Calibration; D019587:Dietary Supplements / Q000032:analysis*; D016018:Least-Squares Analysis; D054709:Lecithins / Q000032:analysis* / Q000737:chemistry; D013024:Soybean Oil / Q000032:analysis* / Q000737:chemistry; D017550:Spectroscopy, Fourier Transform Infrared / Q000379:methods*
D054709:Lecithins; D013024:Soybean Oil