The article was published in Analyst, 2015,140, 98 (doi: 10.1039/c4an01483a). The article describes a new membrane coated voltammetric sensor blood monitoring device for the detection of propofol in blood. For testing and comparison purposes the authors compared device results with results obtained through the extraction of the propofol via mixed mode solid phase extraction (SPE) utilizing UCT’s CLEAN SCREEN DAU columns. The extraction was then followed by HPLC-UV analysis. The results favorably compared the continuous monitoring device to the more traditional, off-line HPLC methodology. The device achieved lower detection limits than the UV detector. UCT, LLC, a leader in the field of sample preparation and chromatography products, continues to lead the way in supporting scientists and engineers in the clinical toxicology community. CLEAN SCREEN® DAU is the most widely used and recognized sorbent for the extraction of drugs from biological matrices.