Determination of patulin in apple juice using magnetic solid-phase extraction coupled with high-performance liquid chromatography

An efficient magnetic sorbent consisting of benzofuran-2-carboxylic acid-loaded magnetic nanocomposite was successfully synthesised for pre-concentration of patulin from apple juice. The prepared magnetic nanocomposite was characterised by scanning electron microscopy, transmission electron microscopy and Fourier-transform infrared spectroscopy. Determination of enriched patulin was performed by high-performance liquid chromatography. The best adsorption conditions were 40mg of sorbent, 50ml of apple juice sample, pH 5, ambient temperature and 25min; the elution conditions were 500l methanol, pH 5, ambient temperature, and 4min. Under optimised conditions, pre-concentration factor was 100, linearity range was 1-400gl(-1) of patulin, limit of detection was 0.15gl(-1) and limit of quantification was 0.5gl(-1). When samples were determined 20 times, the recovery was 93.9-102.6% and the relative standard deviation was below 5.3%. In terms of proposed procedure, the developed method was successfully applied for patulin detection in apple juice samples.