Recent developments in microextraction techniques for detection and speciation of heavy metals

Analysis of heavy metals and their species in complex samples such as environment, biology and medicine is be of paramount importance due to their toxicity, persistence, and bioaccumulation. Considering the complexity of the sample matrix and the low concentration of heavy metals, sample preparation step should be exerted before analysis. Microextraction techniques have received extensive attention due to its miniaturization, quickness, low cost, environmental friendliness, and satisfactory extraction performance. So far, various formats based on microextraction techniques have been developed and applied to entrap heavy metals and related species. This review mainly concentrates on the recent development and applications of microextraction techniques including solvent-based liquid-phase microextraction and sorbent-based solid-phase microextraction for the detection and speciation of heavy metals in water, food, sediment, soil, hair, urine, and serum samples.