Microfluidic device and method

Patent metadata

Field	Value
Publication number	US-12558688-B2
Application number	US-202017072332-A
Country	US
Kind code	B2
Filing date	Oct 16, 2020
Priority date	Mar 18, 2016
Publication date	Feb 24, 2026
Grant date	Feb 24, 2026

Abstract

A combination of components in a capillary flow channel uses capillary forces to passively control the movement of liquid samples within a microfluidic device. To detect a target, a liquid sample introduced to a proximal portion of capillary channel of a microfluidic device moves by capillary action along the specific components of capillary channel.

First claim

What is claimed is:

1 . A microfluidic device comprising:
a port configured to receive a liquid sample, a filter pocket, a mixing well, and a capillary flow channel; wherein the capillary flow channel comprises a proximal opening, a distal opening, a dry reagent zone, a pinch region, and a detection zone; wherein the filter pocket comprises a filter and disposed substantially at the proximal opening; wherein the mixing well comprises a length, a width, a height, and a perimeter, the width decreasing from a central portion of the mixing well toward the perimeter along at least two opposed directions, wherein the mixing well is disposed distal to the filter pocket; wherein the dry reagent zone containing a reagent, the dry reagent zone disposed distal to the mixing well; wherein the pinch region is configured to redirect flow, wherein the pinch region is disposed distal to the dry reagent zone and has a width that is less than that of the capillary flow channel; wherein the pinch region has a width that is at most half the width of the capillary flow channel; wherein the detection zone is disposed distal to a fluid resistance feature, wherein the distal opening is tapered to control a flow rate, and wherein the filter pocket, the mixing well, the dry reagent zone, pinch region, and the detection zone are in fluidic communication.

2 . The microfluidic device of claim 1 , wherein the filter pocket comprises a sample inlet having a recess configured to receive a liquid sample, a filter landing, and a vent configured to permit air to be displaced upon receiving the liquid sample.

3 . The microfluidic device of claim 2 , wherein the filter landing includes a raised plateau extending from a distal edge of the filter pocket.

4 . The microfluidic device of claim 2 , wherein the filter pocket further comprises a catwalk strip disposed for directing a fluid deposited at the sample inlet to the filter landing.

5 . The microfluidic device of claim 1 , wherein the mixing well is dimensioned to move a filtered liquid sample by capillary action.

6 . The microfluidic device of claim 1 , wherein the dry reagent zone contains walls with a hydrophobic ink.

7 . The microfluidic device of claim 1 , wherein the pinch region is configured with a lobe, optionally wherein the pinch region comprises a portion of the capillary flow channel that is lobed in a direction that is substantially perpendicular to a length of the microfluidic device.

8 . The microfluidic device of claim 1 , wherein the detection zone contains at least one solid phase capture spot configured to bind a specific analyte.

9 . The microfluidic device of claim 1 , further comprising two or more solid phase capture spots arranged in a series along a length of the detection zone.

10 . The microfluidic device of claim 8 , wherein the at least one solid phase capture spot provides a signal measured by a reader.

11 . The microfluidic device of claim 1 , further comprising a waste channel distal to the detection zone.

12 . The microfluidic device of claim 11 , wherein a portion of a substrate covers the waste channel and that portion is printed with hydrophobic ink that increases flow rate and decreases wash time.

13 . The microfluidic device of claim 1 , wherein the capillary flow channel is disposed between an upper substrate and a lower substrate.

14 . The microfluidic device of claim 13 , wherein the lower substrate comprises a first portion having a first depth and a second portion having a second depth that is less than the first depth.

15 . The microfluidic device of claim 14 , wherein a portion having a first depth is convex and a portion having a second depth is planar.

16 . The microfluidic device of claim 1 , wherein the filter pocket is configured to move liquid by capillary action along the capillary flow channel and into the mixing well of the capillary flow channel.

17 . The microfluidic device of claim 7 , wherein the mixing well is configured to move liquid by capillary action along the capillary flow channel and into the pinch region of the capillary flow channel.

18 . The microfluidic device of claim 1 , wherein the mixing well comprises a depth that is greater than a depth of the capillary flow channel.

19 . A method for determining a presence or an absence of a cardiac troponin in a patient sample, comprising:
placing a blood sample on a microfluidic device of claim 1 to label the cardiac troponin, if present in the patient sample, with a label comprising a binding partner for the cardiac troponin and a detectable moiety; and detecting a presence of cardiac troponin in the patient sample by determining a presence or an absence of the label, wherein detection of the presence of the label indicates the presence of cardiac troponin in the patient sample, wherein an assay has a limit of quantitation of about 3 μg/mL with a coefficient of variation of less than about 20%.

20 . The method of claim 19 , wherein the cardiac troponin is cardiac troponin I (cTnI).

21 . The method of claim 19 , wherein the cardiac troponin is cardiac troponin T (cTnT).

22 . The method of claim 19 , wherein the cardiac troponin is a complex of cTnI and cTnT.

23 . The microfluidic device of claim 1 , wherein the mixing well is substantially bowl-shaped.

Assignees

• Quidel Cardiovascular Inc
• Ortho Clinical Diagnostics Inc

Inventors

• Olsson Erik Mikael
• Derfus Austin
• Tovar Armando
• Davidson Justin
• Do Tuan
• Crivelli Paul
• Wang Matthew

Classifications

• G01N33/6887

  from muscle, cartilage or connective tissue · CPC title

• G01N33/54306

  Solid-phase reaction mechanisms · CPC title

• B01L2300/0883

  Serpentine channels · CPC title

• B01L3/502723

  characterised by venting arrangements · CPC title

• G01N33/491

  by separating the blood components (G01N15/05 takes precedence) · CPC title