Thin film microextraction based on Co3O4@GO-Nylon‐6 polymeric membrane to extract morin and quercetin and determining them through high performance liquid chromatography-ultraviolet detection

Abstract The in-situ synthesis of one-dimensional Co3O4@GO nanosorbent and its fabrication into the layers of Nylon-6 polymer have been introduced in the present study. The extraction performance of the prepared membrane was studied through using the prepared membrane for thin-film microextraction of two selected flavonoids (as the model compounds) from different kinds of juice and black tea. The extracted analytes (morin and quercetin) were quantified via high performance liquid chromatography-ultraviolet detection (HPLC-UV). The experimental design optimization strategy including Central Composite Design (CCD) was employed to optimize different TFME variables. The selected factors that were once thought to be effective on TFME were screened by Plackett–Burman Design before the optimization. The following figures of merit were obtained under the achieved optimized condition: the Linear Dynamic Ranges (LDRs): 5.0–500.0 μg L−1 and 5.0–200.0 μg L−1, Limits of Determination (LODs): 1.3 μg L−1 and 1.6 μg L−1, Limits of Quantification (LOQs): 4.3 μg L−1 and 5.1 μg L−1, the Relative Standard Deviations (RSDs)