Amino acids- based hydrophobic natural deep eutectic solvents as a green acceptor phase in two-phase hollow fiber-liquid microextraction for the determination of caffeic acid in coffee, green tea, and tomato samples

•New hydrophobic natural deep eutectic solvents were prepared.•The prepared solvents were used in a two-phase hollow fiber-liquid phase microextraction procedure.•The natural deep eutectic solvent was easily prepared by mixing serine with lactic acid.•This method was successfully applied for the analysis of caffeic acid in food samples.•The proposed method is simple, rapid, and environment-friendly.