A simplified gas liquid chromatographic determination for vitamin E in vegetable oils

1977 ◽  
Vol 54 (10) ◽  
pp. 421-423 ◽  
Author(s):  
Kenneth T. Hartman
2000 ◽  
Vol 83 (3) ◽  
pp. 627-634 ◽  
Author(s):  
Josep Serra Bonvehi ◽  
Francesc Ventura Coll ◽  
Imma Alsina Rius

Abstract A precise and selective liquid chromatographic procedure for determining tocopherol and tocotrienol isomers in vegetable oils, formulated preparations, and biscuits was developed and validated. The proposed method quantitates vitamin E in better conditions of recoverability and reproducibility than the standard saponification procedure. Tocopherols and tocotrienols were extracted in hexane from vegetable oils, passed through a silica Sep-pak, chromatographed on a μ-Bondapak C18 column with a mobile phase of methanol–water (95 + 5, v/v), identified at 292 nm, and detected with fluorescence procedure (excitation 296 nm, and emission 330 nm). The correlation coefficient on the calibration curve was 0.9995 over the range of 0.1 to 100 μg/mL. Overall recovery of vitamin E isomers was 93%; coefficients of variation for intra- and interday precision, <2.25%. The results obtained from extraction methods 1 (with saponification) and 2 (without saponification) were compared by ANOVA test. Significant differences appeared between vitamin E isomers (p ≤ 0.05).


1989 ◽  
Vol 35 (12) ◽  
pp. 2285-2289 ◽  
Author(s):  
B E Cham ◽  
H P Roeser ◽  
T W Kamst

Abstract We describe a high-performance liquid chromatographic procedure for the simultaneous measurement of vitamins K1 and E in human serum. Delipidated human serum (free of vitamins K1 and E) was used to make standard solutions of these vitamins, and cetyl naphthoate and alpha-tocopheryl acetate were the internal standards for vitamin K1 and vitamin E, respectively. A simple, novel separation method utilizing liquid-liquid partition chromatography was used as a preparative "clean-up" procedure. Cetyl naphthoate and vitamin K1 (after post-column reduction) were detected by fluorescence, alpha-tocopheryl acetate and vitamin E by ultraviolet absorption. Sensitivity (detection limit) of the assay was 30 pg for vitamin K1 and 5 ng for vitamin E per injection. The method is specific, precise, and more rapid than previously described procedures. Within- and between-assay CVs were 8.1% and 12.9%, respectively, for vitamin K1; 3.5% and 6.0%, respectively, for vitamin E. Analytical recoveries of vitamins K1 and E were 80% and 93%, respectively, from serum and from delipidated serum (standards). The average neonatal serum concentration of vitamin K1 was 83 ng/L, 2.5 mg/L for vitamin E; for normolipidemic adults, the values were 343 ng/L and 7.9 mg/L, respectively, and for hyperlipidemic adults, 541 ng/L and 11.1 mg/L, respectively.


1974 ◽  
Vol 57 (5) ◽  
pp. 1089-1091
Author(s):  
David O Edlund ◽  
Florido A Filippini ◽  
James K Datson

Abstract A gas-liquid chromatographic procedure used to determine vitamin D2 in multiple vitamin tablets has been modified to make it applicable for analysis of multiple vitamin tablets containing minerals and vitamin E acetate. The procedure modifications involve pre-extraction with ether, solution in an alcoholic sulfuric acid-pyridine mixture, and column chromatographic separation on phosphate-treated alumina. The modified procedure has been statistically evaluated. A 2.2% coefficient of variation and 100.3% average recovery were obtained for the samples evaluated.


1975 ◽  
Vol 58 (2) ◽  
pp. 272-275 ◽  
Author(s):  
David T Williams ◽  
Walter F Miles

Abstract Vinyl chloride in foods is determined by gasliquid chromatography either by direct injection of vinegars and alcoholic beverages or by headspace analysis of vegetable oils. The lower limit of detection is 10–15 ng/ml for direct injection and 5–10 ppb for headspace analysis. Confirmation by gas chromatography-mass spectrometry, single ion monitoring at m/e 62, is possible at 50 ppb for either method. The levels of vinyl chloride found in foods packaged in polyvinyl chloride bottles were 0.0–1.6 μg/ml for alcoholic beverages, 0.0–8.4 μg/ml for vinegars, and 0.3–3.3 ppm for peanut oil.


1987 ◽  
Vol 36 (7) ◽  
pp. 506-514 ◽  
Author(s):  
Satoshi NAKASATO ◽  
Haruhiko HOSHIDA ◽  
Takenori MARUYAMA ◽  
Takashi UJIIE ◽  
Yoshio OHTA ◽  
...  

1983 ◽  
Vol 66 (2) ◽  
pp. 304-308
Author(s):  
Teruhisa Hirayama ◽  
Naohide Yamada ◽  
Motoshi Nohara ◽  
Shozo Fukui

Abstract A simple high performance liquid chromatographic (HPLC) method has been developed for determining malondialdehyde (MDA) in vegetable oils. MDA was reacted with dansyl hydrazine in an acidic medium, and the product, 1-dansyl-pyrazole, was determined by HPLC, using a Zorbax sil column with mixed mobile phase of n-hexane-methylene chloride. MDA can be determined as 1-dansyl-pyrazole by f luorometric detection at a level of 0.01 ppm in vegetable oils.


Sign in / Sign up

Export Citation Format

Share Document