An instrument and method for creating a precise capsulorhexis as a step in cataract surgery is described. In embodiments, low-abundance proteins can be focused and separated with high resolution using separation techniques including isoelectric focusing, andor dynamic field gradient focusing in combination with nanofluidic channels andor multi-gate nanofluidic field-effect-transistors. The substrate support structure may include one or more alignment members, one or more hard stop members andor a support plate attached to the printed circuit board for positioning the substrate with respect to the printed circuit board. The respective conductive patterns and the corresponding respective pins of the upper and lower semiconductor chips are bonded together.