Dispersive liquid-liquid microextraction coupled with derivatization: A review of different modes, applications, and green aspects

DLLME is widely used as a sample preparation technique due to its unique advantages of fast extraction, low solvent consumption, high enrichment factors, and low cost. DLLME extracts are generally analyzed by gas or liquid chromatography coupled with different detection systems. However, GC or LC cannot analyze/separate many analytes due to their structural properties. Similarly, some of the analytes are not sensitive to commonly used detectors. In such cases, a derivatization process (chemical conversion) is often applied to improve the structural features of the analytes to make them compatible with separation and/or detection system. The coupling of derivatization with DLLME is a simple way to accomplish the job using minimum volumes of the derivatizing reagents and reducing their impact on workers and the environment. This review explains the different modes of DLLME coupled derivatizations, their applications, and green aspects in a systematic way.