Determination of short-chain fatty acids in serum by hollow fiber supported liquid membrane extraction coupled with gas chromatography.
A method based on hollow fiber supported liquid membrane extraction coupled with a gas chromatograph equipped with flame ionization detector (GC-FID) was developed for the determination of six short-chain fatty acids including acetic acid, propionic acid, i-butyric acid, n-butyric acid, i-valeric acid and n-valeric acid in serum. Hollow fiber supported liquid membrane extraction was employed for preconcentration and clean-up of the samples. The fatty acids were extracted from the acidic donor (diluted serum) into a liquid membrane formed in the wall of the hollow fiber with 10% tri-n-octylphoshphine oxide (TOPO) in di-n-hexyl ether, and then extracted back into a basic acceptor solution filled in the lumen of the hollow fiber. After being acidified with HCl, the acceptor was directly analyzed by GC-FID. The acceptor concentration, donor pH, membrane liquid and extracting time were optimized giving an enrichment factor up to 155 times. The good linearity (r(2)>0.980), reasonable recovery (87.2-121%), and satisfactory intra-assay (8.2-11.5%) and inter-assay (6.1-11.6%) precision illustrated the good performance of the present method. Limits of detection (LOD) ranged from 0.04 to 0.24 microM and limits of quantification (LOQ) varied from 0.13 to 0.80 microM.
Zhao
Guohua
G
Food College of Southwest University, Beibei 400715, Chongqing, PR China.
Liu
Jing-Fu
JF
Nyman
Margareta
M
Jönsson
Jan Ake
JA
D002849:Chromatography, Gas / Q000379:methods*; D005227:Fatty Acids / Q000097:blood*; D006801:Humans; D006863:Hydrogen-Ion Concentration; D008567:Membranes, Artificial; D012680:Sensitivity and Specificity
D005227:Fatty Acids; D008567:Membranes, Artificial