Determination of organic acids in dried Actinidia arguta by pipette tip-based micro matrix solid-phase dispersion coupled with high performance liquid chromatography

Abstract

In this work, a lab-made and affordable pipette tip microextraction strategy was developed for rapid extraction of five organic acids in fruit samples. In this method, 10 mg silica gel /PSA (m/m; 2:1) as a dispersant was fully mixed with 5 mg sample and filled to 1000 μL pipette tip, which was then connected to the pipette The sample is eluted, and the subsequent desorption steps are conducted by aspirating/dispensing the suitable solvents. This methodology provides satisfactory results when compared with previous pipette tip extraction strategies (i.e., pipette-tip solid-phase extraction and dispersive pipette extraction). In addition, the aspiration/dispensing cycle it requires is simple to operate and not commercially dependent. The present method was successfully applied to the analysis of real dried A. arguta samples possessed in different conditions, which proves its feasibility. Under the optimized conditions, low limits of detection and quantification (0.3–1.7 μg mL⁻¹ and 1.0–5.8 μg mL⁻¹, respectively), good precision (RSD<10.3 %) and relative recoveries between 72.0 % and 89.3 % were obtained with only 500 μL (pH = 4.0) of water as elution solvent and 30 times adsorption/ desorption cycles, which requires few minutes per sample. Furthermore, the newly developed in-pipette-tip Micro-MSPD method would be promising for the extraction of various kinds of organic acid analyses in fruits samples prior to instrument detection.