Supercritical CO2 applications in microfluidic systems

Abstract

Supercritical fluid technology has been used for a variety of applications for decades and received special attention in the fields of analytics, extraction and purification of valuable compounds and preparation of drug carriers. Among supercritical fluids, supercritical CO2 is the most attractive one as being nontoxic, nonflammable and chemically inert. In addition, the critical temperature and pressure of CO2 is quite moderate which makes supercritical CO2 a popular solvent for a wide range of applications from laboratory to industrial scale. In recent years, a promising research field called as supercritical microfluidics was developed to merge the advantages of supercritical fluids and microfluidics, the science and technology of manipulating liquids in extremely small volume. This review discusses the recent progress in supercritical microfluidics with a focus on supercritical CO2, the most commonly used solvent in supercritical fluid processes, and some applications of supercritical CO2 in microscale such as extraction of valuable compounds, determination of dissolution characteristic in various solvents, performing chemical reactions and particle synthesis are presented.