Miniaturized green liquid‐phase sample pre‐concentration methods for pharmaceutical drugs assessment in wastewater

Abstract Microextraction methods such as hollow fibre‐liquid phase microextraction (HF‐LPME), dispersive liquid–liquid microextraction (DLLME), single‐drop microextraction (SDME) and ultrasound‐assisted emulsification microextraction (USAEME) have become prominent for analysing pharmaceuticals in wastewater. HF‐LPME, particularly the three‐phase system, excels in extracting pollutants with high efficiency. SDME, especially the direct immersion (DI) variant, is effective for moderately polar and non‐polar compounds. DLLME uses an immiscible dispersion and extraction solvent to separate analytes, while USAEME enhances extraction using ultrasonic waves. Recent research trends focus on incorporating ionic liquids and deep eutectic solvents to improve extraction performance. These miniaturized techniques offer high selectivity, efficient sample clean‐up and significant enrichment factors, making them superior to traditional methods like liquid–liquid extraction. Future developments are expected to further refine these methods for even better performance in pharmaceutical analysis. Complex‐Green Analytical Procedure Index (GAPI) is also used in research to assess the environmentally friendliness of the methodological approaches.