Diagnostic devices and apparatus for the controlled movement of reagents without membranes

• US 20020086436A1
• Filed: 10/18/2001
• Published: 07/04/2002
• Est. Priority Date: 05/21/1992
• Status: Active Grant

• Current Assignee: BIOSITE INCORPORATED (Abbott Laboratories Incorporated)
• Original Assignee: BIOSITE INCORPORATED (Abbott Laboratories Incorporated)
• Inventors: Buechler, Kenneth F.
• Granted Patent: US 6,905,882 B2
• Time in Patent Office: Days
• US Class Current: 436/164
• CPC Class Codes: B01L 2200/0621 Control of the sequence of chambers filled or emptied
• CPC Class Codes: B01L 2200/12 Specific details about manufacturing devices
• CPC Class Codes: B01L 2300/041 Connecting closures to device or container
• CPC Class Codes: B01L 2300/0816 Cards, e.g. flat sample carriers usually with flow in two horizontal directions
• CPC Class Codes: B01L 2300/089 Virtual walls for guiding liquids
• CPC Class Codes: B01L 2400/0688 surface tension valves, capillary stop, capillary break
• CPC Class Codes: B01L 2400/086 using baffles or other fixed flow obstructions
• CPC Class Codes: B01L 3/502746 characterised by the means for controlling flow resistance, e.g. flow controllers, baffles B01L3/502738 takes precedence
• CPC Class Codes: G01N 33/54386 Analytical elements
• CPC Class Codes: Y10S 436/805 Optical property
• CPC Class Codes: Y10S 436/806 Electrical property or magnetic property
• CPC Class Codes: Y10T 436/25375 Liberation or purification of sample or separation of material from a sample [e.g., filtering, centrifuging, etc.]
• CPC Class Codes: Y10T 436/2575 Volumetric liquid transfer

Abstract

The assay devices, assay systems and device components of this invention comprise at least two opposing surfaces disposed a capillary distance apart, at least one of which is capable of immobilizing at least one target ligand or a conjugate in an amount related to the presence or amount of target ligand in the sample from a fluid sample in a zone for controlled fluid movement to, through or away the zone. The inventive device components may be incorporated into conventional assay devices with membranes or may be used in the inventive membrane-less devices herein described and claimed. These components include flow control elements, measurement elements, time gates, elements for the elimination of pipetting steps, and generally, elements for the controlled flow, timing, delivery, incubation, separation, washing and other steps of the assay process.

Claims

74. A method for regulating fluid flow in a device that conducts fluid through one or more capillary channels, comprising:

introducing fluid into a capillary channel comprising (i) a first capillary region comprising a hydrophilic surface and (ii) a second capillary region comprising a hydrophobic surface adjacent to said first capillary region, whereby fluid flows through said first capillary region to contact said hydrophobic surface.

75. The method of claim 74, wherein said device further comprises a third capillary region comprising a hydrophilic surface adjacent to said second capillary region, wherein said hydrophobic surface controls the rate of flow of said fluid into said third capillary region.

76. The method of claim 75, wherein said hydrophobic surface delays fluid flow into said third capillary region until rendered hydrophilic.

77. The method of claim 74, wherein said device comprises a plurality of capillary channels, one or more of which comprise a region comprising a hydrophobic surface.

78. The method of claim 75, wherein said device further comprises a vent.

80. The method of claim 79, further comprising contacting said fluid with a first capillary region and a second capillary region adjacent to said first capillary region, wherein a difference in capillarity of said first capillary region compared to said second capillary region alters a rate or direction of said fluid flow within said device in comparison to the rate or direction of said fluid flow within said device in the absence of said difference in capillarity.

81. The method of claim 79, further comprising contacting said fluid with a reagent dried on a surface of the device, whereby said reagent dissolves into said fluid, thereby lowering the surface tension of said fluid.

82. The method of claim 79, wherein said device comprises a plurality of capillary channels.

83. The method of claim 79, wherein one or more of said hydrophobic regions are flanked by hydrophilic regions.

84. The method of claim 79, wherein at least one of said hydrophobic regions alter the rate of flow within said device.

85. The method of claim 84, wherein said hydrophobic region(s) that alter the rate of flow within said device retard fluid flow until rendered hydrophilic.

79. A method for regulating fluid flow in a device that conducts fluid through one or more capillary channels, comprising:

contacting said fluid with one or more hydrophobic regions on a capillary surface that alter a rate or direction of said fluid flow within said device in comparison to a rate or direction of fluid flow within said device in the absence of said hydrophobic region.

86. A device that conducts fluid through one or more capillary channels, comprising:

a capillary channel comprising (i) a first capillary region comprising a hydrophilic surface and (ii) a second capillary region comprising a hydrophobic surface adjacent to said first capillary region.

87. The device of claim 86, wherein said device further comprises a third capillary region comprising a hydrophilic surface adjacent to said second capillary region.

88. The device of claim 86, wherein said hydrophobic surface alters a rate or direction of fluid flow within said device.

89. The device of claim 86, further comprising a reagent dried on a surface of the device that, when dissolved into reagent dissolves into fluid within said device, lowers the surface tension of said fluid.

90. The device of claim 86, wherein said device comprises a plurality of capillary channels.

91. A method for regulating fluid flow in a device that conducts fluid through one or more capillary channels, comprising:

introducing fluid into a capillary channel comprising (i) a first capillary region comprising a surface having a first contact angle and (ii) a second capillary region adjacent to said first capillary region comprising a surface having a second contact angle less than that of said first contact angle, whereby fluid flows through said first capillary region to contact said second capillary region.

92. The method of claim 91, wherein said device further comprises a third capillary region adjacent to said second capillary region comprising a surface having a third contact angle greater than that of said second contact angle, wherein the rate of flow of said fluid into said third capillary region is regulated by the flow of fluid through said second capillary region.

93. The method of claim 92, wherein said second capillary region delays fluid flow into said third capillary region until said second contact angle is increased.