The document introduces a method for the determination of 5-MOP and 8-MOP in lemon oil and orange oil using the Agilent 1290 Infinity LC system. At 1000 bar, the total analysis time in reversed-phase (RP) liquid chromatography (LC) with acetonitrile and water as mobile phase components could be reduced to 4 min. In the framework of green chromatography, and the present ace- tonitrile shortage, mobile phases constituted of water/methanol and water/ethanol were compared to water/acetonitrile. The influence of the nature of organic modifiers on selectivity and peak capacity was investigated. The figures of merit of the different methods were compared for the determination of 5-MOP in a lemon oil sample con- taining approximately 50 mg/kg. 8-MOP was not detected at the ppm level. The detection limit for both furocoumarins was approximately 1 mg/kg citrus oil.
The document details an analysis of lemon and orange oils for the presence of furocoumarins, specifically 5-methoxypsoralen (5-MOP) and 8-methoxypsoralen (8-MOP). The study utilizes the Agilent 1290 Infinity LC system with UV detection to evaluate different mobile phases.
The note compares standard water/acetonitrile methods with 'green' alternatives using methanol or ethanol. It also investigates high-speed analysis capabilities by increasing flow rates and reducing column length, demonstrating that the system can achieve total analysis times of approximately 4 minutes at pressures up to 1090 bar.
The Agilent 1290 Infinity LC system is rated to 1200 bar.
The detection limit for both furocoumarins was approximately 1 mg/kg citrus oil.
An average concentration of 5.46 pg/mL was detected in the sample solution.