Development of an HPLC/diode-array/fluorimetric detector method for monitoring tocopherols and tocotrienols in edible oils

Citation
P. Gama et al., Development of an HPLC/diode-array/fluorimetric detector method for monitoring tocopherols and tocotrienols in edible oils, J LIQ CHR R, 23(19), 2000, pp. 3011-3022
Citations number
18
Categorie Soggetti
Chemistry & Analysis","Spectroscopy /Instrumentation/Analytical Sciences
Journal title
JOURNAL OF LIQUID CHROMATOGRAPHY & RELATED TECHNOLOGIES
ISSN journal
10826076 → ACNP
Volume
23
Issue
19
Year of publication
2000
Pages
3011 - 3022
Database
ISI
SICI code
1082-6076(2000)23:19<3011:DOAHDM>2.0.ZU;2-M
Abstract
This paper describes an HPLC procedure for the determination of tocopherols and tocotrienols in crude and edible vegetable oils. The sample preparatio n only involves a dissolution of the oil in n-hexane and filtration. The ch romatographic separation was achieved using a normal phase column LiChrosor b SI 60 (5 mum; 25.0 x 0.4 cm). Isocratic elution was carried out using n-h exane :2-propanol (99.7:0.3). The effluent was monitored by using diode-arr ay and fluorimetric detectors. The determinations were performed in the following linear ranges: 0.5-7.5 m ug/mL for alpha -tocopherol and beta -tocotrienol; 0.5-10 mug/mL for beta - tocopherol; and 0.5-15 mug/mL for alpha -tocotrienol, gamma -tocopherol, ga mma -tocotrienol, and delta -tocopherol. Extensive quality assurance of the proposed method was performed by the sta ndard addition method in both crude and edible oil. For edible oil, the pre cision obtained (n=10) was better than 1.8, 2.0, and 1.4 CV% for alpha, bet a, and gamma -tocopherol, respectively; for crude oil it was better than 1. 9, 2.4, and 2.4% for alpha, beta, and gamma -tocopherol, respectively. Furthermore, for edible oil the mean recovery values were between 96-116%, 58-69%, and 111-115% for alpha, beta, and gamma -tocopherol, respectively; for crude oil recovery values were between 85-95%, 63-66%, and 99-103% for the same tocopherols, respectively. The proposed method appears to be an adequate method for quality control an d helpful for authenticity verification by the official control in oil indu stry.