Background: In this work, an extraction method has been developed based on the dispersive liquid-liquid microextraction (DLLME) and liquid antisolvent precipitation (LAP) methods. In DLLME, an extraction solvent is mixed with a dispersive solvent and this solvent mixture is then rapidly injected into the aqueous sample [1]. The rapid injection of the extraction-dispersive solvent mixture produces a cloudy solution, formed of microdroplets of extraction solvent dispersed in the aqueous sample. Partitioning of analytes into the extraction phase is instantaneous due to the very high collective surface area of the droplets. This leads to very high enrichment factors and very low solvent consumption, relative to other liquid or solid phase extraction methods. On the other hand, LAP involves the formation of analyte particles in the solution by adding an antisolvent to the sample solution [2]. The driving force of a LAP process is the supersaturation of the solution produced by mixing the analyte solution and the antisolvent. Methods: In the newly developed method, the extraction solvent in DLLME has been replaced with the antisolvent of LAP. Upon optimization of the chemical conditions such as pH, contact time, and temperature, the solubility of the analyte in the antisolvent is minimized so the analyte precipitates on the surface of the antisolvent nanodroplets which act as the nucleation site. Then, the precipitate is separated using centrifugation and is dissolved in a solvent for further UV-vis determination experiments. To evaluate the method efficiency, two model analytes (i.e. doxorubicin and methylene blue) were extracted and determined under the optimized conditions. Results: The results showed that the method provides high efficiency in the determination of the investigated analytes in terms of the analytical figures of merits. The dynamic linear ranges for doxorubicin and methylene blue were 0.1-10 μM (LOD: 36 nM, R 2 : 0.999, recoveries: 98.8%- 95.3%) and 0.1
