Polyetheretherketone (PEEK) connecting tubing may be used as a solvent holder and as the fluid delivery duct while being immersed in a continuously flowing sample solution, in a liquid-liquid microextraction method termed as continuous-flow microextraction (CFME) for dilute analytes. It may also be used in a flow through cell, in experiments performed to measure the solubility of zinc oxide from 150 to 300°C.
