Development and validation of liquid chromatographic method for the determination of lycopene in plasma

An isocratic reversed-phase liquid chromatographic method with spectrophotometric detection (472 nm) was developed and validated for the determination of lycopene in isolated lycopene crude material and in plasma. The method utilizes a Nova Pak C-18 column (3.9 mm x 150 mm), 5 mum particle size, with a pre-column of the same type and a mobile phase consisting of methanol: acetonitrile: methylene chloride (55:30:15 (%, v/v)) at a flow rate of 1.0 ml min(-1). The rentention time of lycopene was 4.8 min and the total run time was 8 min. Experiments were carried out at room temperature in the absence of direct sunlight. The isolation of lycopene from plasma was achieved with both liquid-liquid extraction (LLE) and solid-phase extraction (SPE) with recoveries of 94.5 +/- 5.1% and 62.3 +/- 2.6%, respectively. Calibration graphs from plasma standards were linear in the range 0.2-2.5 muM with a detection limit of 0.13 muM for the LLE procedure and 0.067-0.83 muM with a detection limit of 0.043 muM for the SPE procedure. Relative standard deviations were <5% for both procedures. (C) 2002 Elsevier Science B.V. All fights reserved.