A method for separation of phosphatidylcholine, triacylglycerol, non-esterified fatty acids and cholesterol esters from plasma by solid-phase extraction

Citation
Gc. Burdge et al., A method for separation of phosphatidylcholine, triacylglycerol, non-esterified fatty acids and cholesterol esters from plasma by solid-phase extraction, BR J NUTR, 84(5), 2000, pp. 781-787
Citations number
9
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Food Science/Nutrition","Endocrinology, Nutrition & Metabolism
Journal title
BRITISH JOURNAL OF NUTRITION
ISSN journal
0007-1145 → ACNP
Volume
84
Issue
5
Year of publication
2000
Pages
781 - 787
Database
ISI
SICI code
0007-1145(200011)84:5<781:AMFSOP>2.0.ZU;2-B
Abstract
Efficient isolation of individual lipid classes is a critical step in the a nalysis of plasma and lipoprotein fatty acid compositions. Whilst good sepa rations of total lipid extracts are possible by TLC, this method is time co nsuming and a major rate-limiting step when processing large numbers of spe cimens. A method for rapid separation of phosphatidylcholine (PC), non-este rified fatty acids (NEFA), cholesterol ester (CE) and triacylglycerol (TAG) from total plasma lipid extracts by solid-phase extraction (SPE) using ami nopropyl silica columns has been developed and validated. Following initial separation of polar and neutral lipids, individual classes were isolated b y application of solvents with increasing polarity. Recoveries for combined plasma extraction with chloroform-methanol and SPE were (%): PC 74.2 (sd 7 .5), NEFA 73.6 (sd 8.3), CE 84.9 (sd 4.9), and TAG 86.8 (sd 4.9), which wer e significantly greater for TAG and NEFA than by TLC (P<0.001). Both GC-fla me ionisation detector and GC-MS analysis of fatty acid methyl esters demon strated that there was no cross-contamination between lipid classes. Measur ements of repeatability of fatty acid composition for TAG, PC, CE and NEFA fractions showed similar CV for each fatty acid. The magnitude of the CV ap peared to be related inversely to the fractional fatty acid concentration, and was greatest at concentrations of less than 1 g/100 g total fatty acids . There was no evidence of selective elution of individual fatty acid or CE species. In conclusion, this method represents an efficient, rapid alterna tive to TLC for isolation of these lipid classes from plasma.