Use of natural deep eutectic solvents for rapid and sensitive extraction of abscisic acid in different food samples prior to spectrophotometric analysis

This study aimed to develop a cheap and simple sample preparation method with high application potential for the safe determination of abscisic acid at trace levels in different food samples. In this context, a new sample preparation method based on ultrasound-assisted natural deep eutectic solvent-based liquid-liquid microextraction (UA-NADES-LLME) was developed before the spectrophotometric determination of abscisic acid. Four NADESs were prepared and tested to achieve selective and rapid extraction of abscisic acid from food samples. Important experimental variables affecting the UA-NADES-LLME method were optimized with a univariate strategy. The UA-NADES-LLME method has a working range of 15–800 μg L􀀀 1 and a detection limit of 4.5 μg L􀀀 1 for abscisic acid. The UA-NADES-LLME method provided a preconcentration factor of 250 and an enrichment factor of 146 for a sample volume of 125 mL. The precision of the UA-NADES-LLME method was investigated by intraday and interday studies for 30, 300 and 700 μg L􀀀 1 concentrations of abscisic acid. As a result of the studies, the relative standard deviation of the method varied from 1.7 % to 2.8 %. The accuracy of the UANADES- LLME method was tested with recovery values obtained from standard abscisic acid concentrations added to food samples. Finally, the UA-NADES-LLME method was applied to the prepared food samples with the reference method.The results obtained showed that the UA-NADES-LLME method could be successfully applied to the extraction and determination of abscisic acid in complex matrices.