The use of isoprene as a marker in human breath for blood cholesterol has been suggested by a number of researchers. It is theorised that the use of breath isoprene as a non-invasive technique could be effective as a diagnostic tool to assess changes in blood cholesterol levels in individuals. During exercise, isoprene is washed from the muscles and exhaled. The mechanism for this is thought to be via the pulmonary gas exchange process. This is apparent with an initial rise in expired concentration, followed by a decrease and stabilisation. This application uses the Hiden Analytical HPR-20 Transient MS due to the fast response, wide dynamic range and high sensitivity offered by the PIC detector. A proprietary breathing mask was modified to accept a heated Quartz Inlet Capillary.
