Abstract
α-Tocopherol and α-tocopherylquinone in rat tissues and plasma were determined simultaneously by using high-performance liquid chromatography-electrochemical detection (HPLC-ED) with dual electrodes in the series mode. Biological samples were saponified in the presence of a mixture of butylated hydroxytoluene, ascorbic acid, and pyrogallol and then extracted with hexane. The compounds were separated on a C18 column using a mobile phase containing 95% methanol and 0.05 M sodium perchlorate as the supporting electrolyte. After HPLC separation, α-tocopherylquinone was first reduced at an upstream electrode at -500 mV. Both α-tocopherol and the reduction product of α-tocopherylquinone were then oxidized downstream at +600 mV. Only the downstream electrode current was monitored for the determination. Linearity of the standard curves was obtained over the range 5-30 pmol for α-tocopherol and α-tocopherylquinone. Minimum detectable quantities (S/N of 3) were 0.25 pmol for α-tocopherol and 0.31 pmol for α-tocopherylquinone. The method was applied to analysis of the contents of α-tocopherol and α-tocopherylquinone in rat tissues and plasma. By hyperoxia, the content of α-tocopherol was decreased remarkably in lung, and in contrast, the contents of α-tocopherylquinone were increased in all tissues studied with the exception of plasma, though the content of α-tocopherylquinone in normal rats is quite small. The technique is particularly useful in the quantitation of the oxidation of α-tocopherol in biological samples.
| Original language | English |
|---|---|
| Pages (from-to) | 1462-1466 |
| Number of pages | 5 |
| Journal | Chemical and Pharmaceutical Bulletin |
| Volume | 48 |
| Issue number | 10 |
| Publication status | Published - 2000 |
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Keywords
- α-Tocopherol
- α-Tocopherylquinone
- HPLC-ED
- Hyperoxia
- Rat tissue
ASJC Scopus subject areas
- Drug Discovery
- Organic Chemistry
- Chemistry(all)
- Pharmacology
Cite this
Determination of α-tocopherol and α-tocopherylquinone in rat tissues and plasma by high-performance liquid chromatography with electrochemical detection. / Kanazawa, Hideko; Miyata, Chizuko; Itoh, Yoshiko; Urano, Shiro; Matsushima, Yoshikazu.
In: Chemical and Pharmaceutical Bulletin, Vol. 48, No. 10, 2000, p. 1462-1466.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Determination of α-tocopherol and α-tocopherylquinone in rat tissues and plasma by high-performance liquid chromatography with electrochemical detection
AU - Kanazawa, Hideko
AU - Miyata, Chizuko
AU - Itoh, Yoshiko
AU - Urano, Shiro
AU - Matsushima, Yoshikazu
PY - 2000
Y1 - 2000
N2 - α-Tocopherol and α-tocopherylquinone in rat tissues and plasma were determined simultaneously by using high-performance liquid chromatography-electrochemical detection (HPLC-ED) with dual electrodes in the series mode. Biological samples were saponified in the presence of a mixture of butylated hydroxytoluene, ascorbic acid, and pyrogallol and then extracted with hexane. The compounds were separated on a C18 column using a mobile phase containing 95% methanol and 0.05 M sodium perchlorate as the supporting electrolyte. After HPLC separation, α-tocopherylquinone was first reduced at an upstream electrode at -500 mV. Both α-tocopherol and the reduction product of α-tocopherylquinone were then oxidized downstream at +600 mV. Only the downstream electrode current was monitored for the determination. Linearity of the standard curves was obtained over the range 5-30 pmol for α-tocopherol and α-tocopherylquinone. Minimum detectable quantities (S/N of 3) were 0.25 pmol for α-tocopherol and 0.31 pmol for α-tocopherylquinone. The method was applied to analysis of the contents of α-tocopherol and α-tocopherylquinone in rat tissues and plasma. By hyperoxia, the content of α-tocopherol was decreased remarkably in lung, and in contrast, the contents of α-tocopherylquinone were increased in all tissues studied with the exception of plasma, though the content of α-tocopherylquinone in normal rats is quite small. The technique is particularly useful in the quantitation of the oxidation of α-tocopherol in biological samples.
AB - α-Tocopherol and α-tocopherylquinone in rat tissues and plasma were determined simultaneously by using high-performance liquid chromatography-electrochemical detection (HPLC-ED) with dual electrodes in the series mode. Biological samples were saponified in the presence of a mixture of butylated hydroxytoluene, ascorbic acid, and pyrogallol and then extracted with hexane. The compounds were separated on a C18 column using a mobile phase containing 95% methanol and 0.05 M sodium perchlorate as the supporting electrolyte. After HPLC separation, α-tocopherylquinone was first reduced at an upstream electrode at -500 mV. Both α-tocopherol and the reduction product of α-tocopherylquinone were then oxidized downstream at +600 mV. Only the downstream electrode current was monitored for the determination. Linearity of the standard curves was obtained over the range 5-30 pmol for α-tocopherol and α-tocopherylquinone. Minimum detectable quantities (S/N of 3) were 0.25 pmol for α-tocopherol and 0.31 pmol for α-tocopherylquinone. The method was applied to analysis of the contents of α-tocopherol and α-tocopherylquinone in rat tissues and plasma. By hyperoxia, the content of α-tocopherol was decreased remarkably in lung, and in contrast, the contents of α-tocopherylquinone were increased in all tissues studied with the exception of plasma, though the content of α-tocopherylquinone in normal rats is quite small. The technique is particularly useful in the quantitation of the oxidation of α-tocopherol in biological samples.
KW - α-Tocopherol
KW - α-Tocopherylquinone
KW - HPLC-ED
KW - Hyperoxia
KW - Rat tissue
UR - http://www.scopus.com/inward/record.url?scp=0033790917&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=0033790917&partnerID=8YFLogxK
M3 - Article
VL - 48
SP - 1462
EP - 1466
JO - Chemical and Pharmaceutical Bulletin
JF - Chemical and Pharmaceutical Bulletin
SN - 0009-2363
IS - 10
ER -