Sample preparation for micro total analytical systems (μ-TASs)

The integration of sample treatment into a micro total analytical system (μ-TAS) represents one of the remaining hurdles towards achieving truly miniaturized systems. The challenge is made more complex by the enormous variation in samples to be analyzed. Moreover, the pretreatment technique has to be compatible with the analytical device to which it is coupled, in terms of time, reagent and power consumption, and sample volume.This review, with more than 140 references, presents some recent advances and novel strategies for sample preparation in μ-TASs. We classify μ-TAS sample-preparation methods according to the mechanism that links the analyte(s) of interest to substrates: filtration, cell lysis, liquid-liquid extraction, solid-phase extraction, droplet membrane droplet, treatment by nanomaterials, stacking and isotachophoresis. We compare these techniques in terms of sample flexibility, arguing for these applications in some fields, such as biological and environmental. These discussions can help to determine the appropriate sample-preparation technique for generating a true μ-TAS. We provide a critical discussion and some key conclusions.

► We review sample preparation for micro total analytical systems (μ-TASs).
► We compare sample-preparation techniques in terms of sample flexibility.
► Micro total analytical systems (μ-TASs) applied to biology and the environment.
► Sample preparation for generating a true micro total analytical system (μ-TAS).