Determination of α-tocopherol in the traditional chinese medicinal preparation sea buckthorn oil capsule by non-aqueous reversed phase-HPLC

A non-aqueous reversed phase HPLC was developed for determining α-tocopherol in Sea buckthorn oil capsule without the need for saponification. A reversed phase column (Alltima C₁₈, 4.6×250 mm, 5 μm) was used with a mobile phase of methanol-acetonitrile (95 : 5, v/v) and flow rate of 1 ml/min. The contents in capsule were extracted with n-hexane. Detection wavelength was set at 292 nm. Each analysis requires no longer than 20 min. The linearity range for α-tocopherol was 9.4 - 47.0 μg/ml. The detection limit was 0.94 μg/ml. The mean recovery was 95.82 (RSD 2.3%). This method is suitable for quantitative analysis of α-tocopherol in Sea buckthorn oil or its Traditional Chinese Medicinal preparation.