Determination of underivatized long chain fatty acids using RP-HPLC with capacitively coupled contactless conductivity detection.
A reversed-phase high-performance liquid chromatographic method with capacitively coupled contactless conductivity detector (C(4)D) has been developed for the separation and the simultaneous determination of five underivatized long chain fatty acids (FAs), namely myristic, palmitic, stearic, oleic, and linoleic acids. An isocratic elution mode using methanol/1mM sodium acetate (78:22, v/v) as mobile phase with a flow rate of 0.6 mL min(-1) was used. The separation was effected by using a Hypersil ODS C(18) analytical column (250 mm x 4.6 mm x 5 microm) and was operated at 45 degrees C. Calibration curves of the five FAs were well correlated (r(2)>0.999) within the range of 5- 200 microg mL(-1) for stearic acid, and 2-200 microg mL(-1) for the other FAs. The proposed method was tested on four vegetable oils, i.e., pumpkin, soybean, rice bran and palm olein oils; good agreement was found with the standard gas chromatographic (GC) method. The proposed method offers distinct advantages over the official GC method, especially in terms of simplicity, faster separation times and sensitivity.
Makahleh
Ahmad
A
School of Chemical Sciences, Universiti Sains Malaysia, 11800 Penang, Malaysia.
Saad
Bahruddin
B
Siang
Gan Hui
GH
Saleh
Muhammad Idiris
MI
Osman
Hasnah
H
Salleh
Baharuddin
B
D001880:Boranes / Q000737:chemistry; D002138:Calibration; D002849:Chromatography, Gas; D002851:Chromatography, High Pressure Liquid; D056148:Chromatography, Reverse-Phase; D004553:Electric Conductivity; D004951:Esterification; D005227:Fatty Acids / Q000032:analysis* / Q000737:chemistry* / Q000302:isolation & purification; D057230:Limit of Detection; D016014:Linear Models; D000432:Methanol / Q000737:chemistry; D010938:Plant Oils / Q000737:chemistry; D015203:Reproducibility of Results; D013696:Temperature; D013997:Time Factors
D001880:Boranes; D005227:Fatty Acids; D010938:Plant Oils; C021274:boron trifluoride; D000432:Methanol