New approaches for fabrication of microfluidic capillary electrophoresis devices with on-chip conductivity detection

In practice, microfluidic systems are based on the principles of capillary electrophoresis (CE), for a large part due to the simplicity of electroosmo tic pumping. in this contribution, a universal conductivity detector is pre sented that allows detection of charged species down to the muM level. Addi tionally, powderblasting is presented as a novel technique for direct etchi ng of microfluidic networks. This method allows creation of features down t o 50 mum with a total processing time (design to device) of less than one d ay. The performance of powderblasted devices with integrated conductivity d etection is illustrated by the separation of lithium, sodium, and potassium ions and that of fumaric, malic, and citric acid.