Patent ID: 9618506
Date: 2017-04-11
CPC Classifications: B01L,G01N

Claim:
1. A method of performing an assay to detect a presence of the natriuretic peptide in a first liquid sample comprising: (a) introducing the first liquid sample to a first channel portion of a microfluidic device; (b) contacting, within the microfluidic device, magnetically susceptible particles with the first liquid sample, the magnetically susceptible particles comprising a binding agent that specifically binds the natriuretic peptide in the first liquid sample; (c) contacting a second binding agent with the first liquid sample, wherein the second binding agent specifically binds the natriuretic peptide at a different epitope to the binding agent of the magnetically susceptible particle to form complexes comprising the magnetically susceptible particles, the natriuretic peptide and the second binding agent, wherein the second binding agent is conjugated to a detectable label; (d) forming, proximal to a junction between the first channel portion and a second channel portion of the microfluidic device, a first liquid sample:gas interface; (e) forming a first liquid sample:second liquid interface by displacing gas of the first liquid sample:gas interface with a second liquid; (f) magnetically moving the magnetically susceptible particles across the first liquid sample:second liquid interface into the second liquid in the second channel portion; and (g) detecting the complexes containing the natriuretic peptide in the second channel portion based on the activity of the detectable label.