Patent ID: 7172682

Claim:
A method of immobilizing a biomolecule on a microfluidics biochip, comprising the steps of a) providing a microfluidic biochip, comprising a microfluidic component comprising a flow surface; at least two electrodes, whereby an electroosmotic flow can be generated at the flow surface; an immobilizing polymer that is substantially adhered to the flow surface, the polymer comprising a backbone to which are attached a first substituent selected from ionic groups of the same polarity and covalent precursors of the ionic groups, wherein the first substituent is optionally a biomolecule immobilizing group; a second substituent that is a hydrophobic group; and optionally a third substituent that is a biomolecule-immobilizing group; wherein the polymer comprises at least one substituent that is a biomolecule-immobilizing group; b) applying a motive force selected from pressure, electroosmotic force, capillary action, and centrifugal force, thereby generating flow; c) directing a biomolecule from a source to the polymer by employing the flow; and d) reacting the biomolecule with the biomolecule-immobilizing group under suitable reaction conditions, whereby the biomolecule is immobilized.