| In this study, for the first time, surfactant-assisted deep eutectic solvent-based salting-out homogenous liquidliquid
extraction performed in a narrow-bore tube has been introduced as a new sample pretreatment
approach and used for the isolation of natamycin from fruit juices. In this method, firstly, tween 80 (as a surfactant)
and a water-miscible ternary deep eutectic solvent composed of choline chloride: acetic acid: butanol (as
an extractant) were added to the sample solution and a homogenous state was formed. This solution was
transferred into a narrow-bore tube and in the following, the homogenous solution was broken by addition of
sodium chloride (as a phase separation agent). By this action, the analyte was extracted into the produced tiny
droplets of extractant. This phase was quantified by high–performance liquid chromatography-ultraviolet
detection. Experimental conditions of the developed extraction procedure were investigated and optimized by
means of central composite design with variables including surfactant and extraction solvent volume, pH, and
sodium chloride amount. Under optimum conditions, low limits of determination and quantification (0.78 and
2.60 ng mL 1, respectively), acceptable repeatability (relative standard deviations of 4.9 and 7.1% for intra- and
inter day precisions at a concentration of 25 ng mL 1), and satisfactory extraction recovery (76%) were obtained
using the proposed method. At the end, the suggested method was effectively utilized for the analysis of natamycin
in different juice samples. |