A method of preconcentrating trace analytes is accomplished by extracting polar and non-polar analytes through a sol-gel coating. The sol-gel coating is either disposed on the inner surface of a capillary tube or disposed within the tube as a monolithic bed.
Malik, Abdul, "Sample preconcentration tubes with sol-gel surface coatings and/or sol-gel monolithic beds" (2004). USF Patents. 763.
University of South Florida