Pressure-based clog detection in SPE-columns

Abstract: The concept of integrated sensors in the Biotage® Extrahera™ system to perform live-monitoring of pressure inside SPE-columns is investigated. A test-rig containing the components necessary to simulate the pressure-cycle in the system is constructed and a printed-circuit board assembly is designed and implemented into its 24-column format. Liquid samples with varying viscosity are then synthesized using water and glycerol, which are used in a simplified 2-step SPE-process during which the pressure inside the columns is logged. The results obtained showed that the concept is viable and methods for clog detection as well as state assessment are discussed. However, it was established that the solution needs further testing involving complete SPE-processes with real samples before any detailed algorithms can be presented. A pre-study is finally done regarding solutions for minimizing the design to allow for implementation into the system's more spatially restricted 96-column format.