Three stage sample preparation for purification of proteins from complex biological samples

In this manuscript we present a three-component sample preparation platform for delivering proteins, with controlled orientation, purified from a complex biological sample to a sensor surface. The presented platform depletes highly abundant proteins and cells from complex biological samples, and then is capable of immobilizing the target analyte on the surface with controlled immobilization. A herringbone structure is used to mix the test sample with beads coated with antibodies against the highly abundant proteins, which is then fed into a second component, consisting of a filter trench with interdigitated electrodes above for applying dielectrophoretic force. The beads and cells are pushed down into the filter trench, thus allowing only the serum to pass through. In a third step, protein orientation and immobilization is controlled with electric field. In this manuscript we discuss the proof of concept for each of these three components separately.