The present invention relates to matrixes, arrays, systems and methods for analyzing biomolecules by their isoelectric point, optionally, in combination with a second dimension analysis. The assortment of matrixes, arrays and systems provided herein are useful for causing a biomolecule under the influence of an electrical field to accumulate into an IEF buffer that comprises a pH value that is the same as the isoelectric point of the biomolecule. The methods of this invention are useful for, e.g., research and diagnostic purposes.