HPLC method for simultaneous determination of retinol, α-tocopherol and coenzyme Q10 in human plasma

A simple HPLC method with UV detection is proposed for the simultaneous determination of three lipophilic vitamins: all-trans-retinol, alpha-tocopherol and coenzyme Q(10) (ubiquinone) in human plasma. The following chromatographic conditions were used: RP-18 column, a mobile phase consisted of methanol -n-hexane 72:28 (v/v) and UV detector set at 324, 292 and 276 nm for all-trans-retinol, a-tocopherol and coenzyme Q(10), respectively. The linearity range was 0.35-70 mu M for all-trans-retinol, 0.23-44 mu M for a-tocopherol and 0.12-23 mu M for coenzyme Q(10). Deproteinised plasma samples were extracted with n-hexane prior to the analysis. The within-day and between day reproducibilities were 1.5 and 3.7% for all-trans-retinol, 4.0 and 5.8% for alpha-tocopherol and 2.3 and 3.1% for coenzyme Q(10), respectively. Using the proposed method the following recoveries were achieved: 91% for all-trans-retinol, 86% for alpha-tocopherol and 88% for coenzyme Q(10). The method was applied to the determination of the levels of retinol, tocopherol and coenzyme Q(10) in plasma of healthy children and children treated by elimination diet. (c) 2006 Elsevier B.V. All rights reserved.