Microextraction for ambient ionization mass spectrometry analysis

Ambient ionization allows desorption of molecules and formation of ions directly from samples in native environment. Compared with traditional ionization techniques, it has unique features of simplicity and convenience, thus has attracted considerable interest for the development of promising analytical methods. The concept of green analytical chemistry has raised concern about the safety of experimental process, and microextraction techniques can greatly reduce the use of organic solvents. The simple and fast operation of microextraction coincides with the advantages of ambient ionization mass spectrometry (AIMS) to perform high-throughput analysis. The combination of microextraction and AIMS significantly reduces the matrix effect and thus improves the analytical sensitivity and specificity in comparison with AIMS analysis alone. This review summarizes some typical combinations of microextraction and AIMS and their applications in forensic chemistry, food safety, and environmental monitoring.