Determination of coenzyme Q in human plasma.
Coenzyme Q10 (CoQ10) levels in human plasma were determined by high-performance liquid chromatography (HPLC) with UV detection. CoQ10 was dissociated from lipoproteins by methanol and subsequently cleaned-up on silica gel and octadecyl silica solid-phase extraction cartridges. HPLC separation was performed on a C18 reversed-phase column. The methanol-hexane mobile phase provided a greater possibility of separation procedure adjustment allowing the shortest possible elution time without loss of resolution than a two-alcohol mobile phase. Quantitation was based on the peak heights using a standard addition method. The lower limit of detection was 8 ng on-column, corresponding to 90 micrograms ubiquinone per litre of plasma in an actual sample. Thirty-one randomly selected plasma samples from apparently healthy, 18 to 56-year-old individuals (males and females) were analyzed for total CoQ10. The average level in these subjects was 0.47 +/- 0.18 mg/l with the range of 0.26-1.03 mg/l. The method was also applied to the determination of ubiquinone plasma level changes in one healthy volunteer over a period of one month and after oral intake of CoQ10.
Kaplan
P
P
Department of Biochemistry, Faculty of Medicine, Masaryk University, Brno, Czech Republic.
Sebestianová
N
N
Turiaková
J
J
Kucera
I
I
D000293:Adolescent; D000328:Adult; D002138:Calibration; D002851:Chromatography, High Pressure Liquid; D005260:Female; D006801:Humans; D007202:Indicators and Reagents; D008297:Male; D008875:Middle Aged; D010949:Plasma / Q000737:chemistry; D012016:Reference Values; D013056:Spectrophotometry, Ultraviolet; D014451:Ubiquinone / Q000097:blood*
D007202:Indicators and Reagents; D014451:Ubiquinone