Patent ID: 9182411
Filing Date: 2015-11-10
Classification: B01L,G01N

Abstract:
1. A microfluidic device for detection of cerebrospinal fluid (CSF) in a sample, comprising: a microchannel with a loading inlet for loading the sample into the microfluidic device; a filtration chamber fluidically connected to the loading inlet, the filtration channel allowing proteins to flow through but block a flow of cells or particulate matter; a capture/labeling chamber fluidically connected to the filtration chamber and to a valve, the capture/labeling chamber including an immobilized capture agent for capture of transferrin proteins from the sample and which retains specific binding activity for transferrin, the capture/labeling chamber having at least one modified surface with the immobilized capture agents bound thereto, the capture/labeling chamber having an affinity matrix where the immobilized capture agents bind upon contact therewith; while in the capture/labeling chamber, transferrin protein in the sample binds to the immobilized capture agents with the valve remaining closed when the sample occupies the capture/labeling chamber for a period of time equal to or in excess of a time for a binding equilibrium to be reached for binding to the immobilized capture agents, and then washed thereafter allowing unbound sample to exit through an outlet channel; the immobilized transferrin is labeled with a labeling agent that is an antibody (fluorophore) which specifically binds transferrin; the capture/labeling chamber is washed with a buffer solution to remove spent/unreacted labeling agent (fluorophore); the capture/labeling chamber is again washed with a buffer of a non-denaturing detergent provided through the inlet to release bound transferrin from the mobilized capture agents into the IEF chamber; an isoelectrofocusing (IEF) chamber fluidically connected to the capture/labeling chamber, and comprising an IEF gel which separates proteins based on their pI; and a detector operatively connected to the isoelectrofocusing chamber configured to detect the presence of transferrin bands within the IEF gel, wherein the detection of beta-2-transferrin indicates the presence of CSF in the sample.