The proposed innovation is a microfluidic device designed to effect a 2-dimensional resolution of a mixture of proteins based on isoelectric point (pI) and molecular weight (MW). The innovation performs tasks similar to those performed by 2-dimensional ("2-D") gel electrophoresis. To achieve 2-D-gel equivalence with minimal complications and maximum exploitation of the advantages provided by microfluidics a novel approach is proposed. In this approach the user dissolves or mixes a sample to be tested for proteins into a sample buffer and injects this into a plastic card consisting of microfluidic channels and electrodes. The card is inserted into a compact "reader" (small enough for space flight) that, within four hours, electronically reports the abundance of each protein detected. In Phase II research SHOT will (1) establish fabrication parameters for the card and manufacture prototypes, (2) build a breadboard reader and (3) test the Microfluidic Analytical Separator using mixed protein solutions. The innovation is useful in detecting specific protein ratio changes in blood or plasma, in extracts of experimental organisms subjected to varying environmental conditions, and in the medium-resolution high-throughput screening of pharmaceutical agents.