Although chemical instrumentation, such as sensors and micro-devices, microscopy, chromatography, and spectroscopy have undergone exceptional improvement in their sensitivity, still sample preparation step (whose goal is enrichment, cleanup, and signal enhancement) plays the most important role prior to sample analysis. That is because matrices of most samples are complex and the amounts of the analytes in samples are lower than the limit of detection of the instruments. Among all pretreatment methods, solid phase extraction (SPE) has been under continuous development and considered as one of the most important sample preparation methods due to its effectiveness, greenness and simplicity.

This Special Issue aims to review the state of the art of this sample preparation technique and also describe the recent and future advances. It is my pleasure to invite you to submit your manuscript on new SPE sorbents, new applications of common SPE sorbents, miniaturization and green aspects of SPE  for pretreatment of environmental, pharmaceutical, biological and food samples.