A microfluidic device, for use in separation systems, includes a substrate having a fluidic channel. One or more heaters made of a thick film material are integrated with the substrate and in thermal communication with the fluidic channel of the substrate. The one or more heaters produce a thermal gradient within the fluidic channel in response to a current flowing through the one or more heaters. A plurality of electrically conductive taps can be in electrically conductive contact with the one or more heaters. The plurality of electrically conductive taps provides an electrically conductive path to the one or more heaters by which an electrical supply can produce the current flowing through the one or more heaters. Alternatively, the thick film material can be ferromagnetic, and the electrical supply can use induction to cause the current to flow through the one or more heaters.