High-throughput analysis of pesticides in minor tropical fruits from Colombia.

In this work, a method has been applied and validated for the determination of a group of 35 multiclass pesticides in the minor tropical fruits rose apple/pomarrosa (Syzygium malaccense), starfruit/carambola (Averrhoa carambola), yoyomo (Spondias purpurea) and papayuela (Vasconcellea pubescens) cultivated and exported in Colombia. The AOAC 2007.1 QuEChERS method, that uses an acetic acid/acetate buffer, was applied together with gas chromatography coupled to a triple quadrupole mass spectrometer. The method was validated in terms of calibration, recovery at three levels of concentration and matrix effects (MEs). A mixture of analyte protectants was also used. A good linearity was obtained in all cases, while the study of the ME revealed the need of developing matrix-matched calibration for many pesticides. Recovery values were in the range 70-120% with relative standard deviation values less than 20% for most of the pesticides studied. The lowest calibration level was 5 µg/kg. Several samples of each type were analysed.