U.S. patent application number 14/610814 was filed with the patent office on 2015-08-27 for microfluidic devices and method for their use.
The applicant listed for this patent is APPLIED BIOSYSTEMS, LLC. Invention is credited to Jason E. BABCOKE, Dar BAHATT, Nigel P. BEARD, Kevin S. BODNER, Douglas P. GREINER, Stephen J. GUNSTREAM, H. Pin KAO, Kenneth J. LIVAK, Mark F. OLDHAM.
Application Number | 20150238919 14/610814 |
Document ID | / |
Family ID | 52395610 |
Filed Date | 2015-08-27 |
United States Patent
Application |
20150238919 |
Kind Code |
A1 |
OLDHAM; Mark F. ; et
al. |
August 27, 2015 |
Microfluidic Devices And Method For Their Use
Abstract
Exemplary embodiments provide microfluidic devices and methods
for their use. The microfluidic device can include an array of
M.times.N reaction sites formed by intersecting a first and second
plurality of fluid channels of a flow layer. The flow layer can
have a matrix design and/or a blind channel design to analyze a
large number of samples under a limited number of conditions. The
microfluidic device can also include a control layer including a
valve system for regulating solution flow through fluid channels.
In addition, by aligning the control layer with the fluid channels,
the detection of the microfluidic devices, e.g., optical signal
collection, can be improved by piping lights to/from the reaction
sites. In an exemplary embodiment, guard channels can be included
in the microfluidic device for thermal cycling and/or reducing
evaporation from the reaction sites.
Inventors: |
OLDHAM; Mark F.; (Emerald
Hills, CA) ; BAHATT; Dar; (Foster City, CA) ;
LIVAK; Kenneth J.; (Arlington, VA) ; BABCOKE; Jason
E.; (Suisun City, CA) ; KAO; H. Pin; (Fremont,
CA) ; GUNSTREAM; Stephen J.; (Iowa City, IA) ;
BODNER; Kevin S.; (Foster City, CA) ; GREINER;
Douglas P.; (Fremont, CA) ; BEARD; Nigel P.;
(San Diego, CA) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
APPLIED BIOSYSTEMS, LLC |
Carlsbad |
CA |
US |
|
|
Family ID: |
52395610 |
Appl. No.: |
14/610814 |
Filed: |
January 30, 2015 |
Related U.S. Patent Documents
|
|
|
|
|
|
Application
Number |
Filing Date |
Patent Number |
|
|
12145333 |
Jun 24, 2008 |
8945481 |
|
|
14610814 |
|
|
|
|
60946520 |
Jun 27, 2007 |
|
|
|
Current U.S.
Class: |
506/13 |
Current CPC
Class: |
B01L 2300/0816 20130101;
G01N 2201/0407 20130101; B01J 19/0046 20130101; B01L 2300/0819
20130101; B01L 2300/0654 20130101; B01L 2200/10 20130101; B01L
2300/185 20130101; B01L 2200/027 20130101; B01L 7/52 20130101; G01N
21/17 20130101; B01L 3/502738 20130101; B01L 3/502715 20130101;
B01L 2300/0867 20130101; B01L 2400/0655 20130101 |
International
Class: |
B01J 19/00 20060101
B01J019/00; G01N 21/17 20060101 G01N021/17; B01L 7/00 20060101
B01L007/00 |
Claims
1-27. (canceled)
28. A system comprising: a flow layer comprising an array of
reaction sites; a control layer disposed over a plurality of the
reaction sites, wherein the control layer comprises a medium having
a first refractive index and a bulk material having a second
refractive index that is greater than the first refractive index; a
plurality of bulk material sites disposed in the bulk material and
over corresponding reaction sites of the plurality of reaction
sites, the bulk sites configured to confine emission light from the
reaction sites; and a light path of the emission light from one of
the reaction sites through one of bulk material sites and to an
optical detector.
29. The system of claim 28, wherein the bulk material has a greater
refractive index than a media in the adjacent apertures of the bulk
material.
30. The system of claim 28, further comprising a guard layer
underlying the flow layer configured to perform thermal cycling for
one or more of at least some of the fluid channels or at least some
of the reactions sites.
31. The system of claim 30, wherein the thermal cycling comprises
pumping water or ethylene glycol.
32. The system of claim 28, wherein the plurality of reaction sites
are disposed along a first plane and the plurality of apertures are
disposed along a second plane located adjacent the first plane.
Description
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application claims a priority benefit under 35 U.S.C.
.sctn.119(e) from U.S. Patent Application No. 60/946,520 filed Jun.
27, 2007, which is incorporated herein by reference.
FIELD
[0002] This invention relates generally to microfluidic devices
and, more particularly, to microfluidic devices and methods for
their use in chemical and biological analysis and/or synthesis.
DESCRIPTION OF THE RELATED ART
[0003] Microfluidic devices with integrated fluidic circuits are
known in the art. Examples of these are disclosed in U.S. Pat. Nos.
6,802,342; 6,951,632; 6,953,058; and U.S. Patent Publication Nos.
20060006067; 20050129581; and 20050119792, all of which are
incorporated by reference herein in their entirety.
[0004] Conventional microfluidic devices with integrated fluidic
circuits are formed of an elastomeric material and include a
substrate and a plurality of fluid channels. The fluid channels
form arrays of reaction sites to facilitate high throughput
analyses. Alternatively, these devices can include a plurality of
"blind channels" which are reaction sites located at the end of a
fluid channel. These devices promise reduced time, cost, and space
requirements when used for a variety of microfluidic analyses
and/or synthesis. It would therefore be desirable for improved
microfluidic devices that can be used to conduct, for example,
thermal cycling reactions.
BRIEF DESCRIPTION OF THE DRAWINGS
[0005] Various features of the embodiments can be more fully
appreciated, as the same become better understood with reference to
the following detailed description of the embodiments when
considered in connection with the accompanying figures, in
which:
[0006] FIG. 1 is a schematic illustration of a microfluidic device
in accordance with the present teachings.
[0007] FIG. 2 shows an exemplary system for collecting optical
signal from reaction sites in microfluidic channels in accordance
with the present teachings.
DETAILED DESCRIPTION OF EMBODIMENTS
[0008] For simplicity and illustrative purposes, the principles of
the present teachings are described by referring mainly to
exemplary embodiments thereof. However, one of ordinary skill in
the art would readily recognize that the same principles are
equally applicable to, and can be implemented in, all types of
microfluidic devices, and that any such variations do not depart
from the true spirit and scope of the present teachings. Moreover,
in the following detailed description, references are made to the
accompanying figures, which illustrate specific embodiments.
Electrical, mechanical, logical and structural changes may be made
to the embodiments without departing from the spirit and scope of
the present invention. The following detailed description is,
therefore, not to be taken in a limiting sense and the scope of the
present teachings is defined by the appended claims and their
equivalents.
[0009] Notwithstanding that the numerical ranges and parameters
setting forth the broad scope of the invention are approximations,
the numerical values set forth in the specific examples are
reported as precisely as possible. Any numerical value, however,
inherently contains certain errors necessarily resulting from the
standard deviation found in their respective testing measurements.
Moreover, all ranges disclosed herein are to be understood to
encompass any and all sub-ranges subsumed therein. For example, a
range of "less than 10" can include any and all sub-ranges between
(and including) the minimum value of zero and the maximum value of
10, that is, any and all sub-ranges having a minimum value of equal
to or greater than zero and a maximum value of equal to or less
than 10, e.g., 1 to 5.
[0010] According to various embodiments, the exemplary microfluidic
devices can utilize a matrix design, a blind channel design, or a
combination thereof. The matrix design can be used, for example, to
analyze a large number of samples under a limited number of
conditions. The matrix design microfluidic device can include a
plurality of intersecting horizontal and vertical flow channels to
define an array of reaction sites at the intersection of the
horizontal and vertical flow channels. A valve system can enable
solution to flow selectively through either the horizontal or
vertical flow channels such that various flow channels in the
matrix can be selectively isolated. Valves and pumps for regulating
solution flow through flow channels of the device can be
controlled, at least in part, by one or more control channels of a
control layer that are separated from the flow channel by an
elastomeric membrane or segment. In addition, by aligning the
control layer with the flow channels, the detection of the reaction
sites, e.g., optical signal collection, can be improved by piping
the excitation/ emission lights to/ from the reaction sites.
[0011] A portion of an exemplary embodiment of a microfluidic
device 100 using a matrix design is schematically shown in FIG. 1.
Microfluidic device 100 can include a first plurality of fluid
channels 105, wherein one of M different primers (e.g., DNA
primers) can be introduced into each of the first plurality of
fluid channels 105. Although only seven of M fluid channels 105 are
shown in FIG. 1, one of ordinary skill in the art will understand
that more than M and less than M fluid channels 102 are
contemplated. The device can further include a second plurality of
fluid channels 102, wherein one or more of N different samples can
be introduced into each of the second plurality of fluid channels
102. Although only seven of N fluid channels 102 are shown in FIG.
1, one of ordinary skill in the art will understand that more than
N and less than N fluid channels 105 are contemplated. The first
plurality of fluid channels 105 and the second plurality of fluid
channels 102 can intersect to form an array of M.times.N reaction
sites 130. Microfluidic device 100 can further include a first
plurality of valves 107 that control fluid flow within the first
plurality of fluid channels 105 and a second plurality of valves
104 that control fluid flow within the second plurality of fluid
channels 102. In an exemplary embodiment, microfluidic device 100
can include 49 fluid channels into which one of 49 different
primers can be introduced. Exemplary microfluidic device 100 can
further include an additional 49 fluid channels, into which 49
different samples can be introduced. The exemplary microfluidic
device can then have 2401 reaction sites.
[0012] According to various other embodiments, the exemplary
microfluidic devices can utilize a blind channel design that
includes a plurality of blind channels. The blind channels can be
flow channels having a dead end or isolated end such that solution
can only enter and exit the blind channel at one end. Blind channel
design microfluidic devices can be used to conduct a large number
of analyses under different conditions with a limited number of
samples. These devices differ from matrix design devices as they
require only a single valve for each blind channel that forms a
reaction site.
[0013] In matrix and blind channel microfluidic devices, flow of
solution can be controlled, at least in part, by one or more
control channels that are separated from the flow channel by an
elastomeric membrane or segment. Referring back to FIG. 1, a first
control channel 109 can control valves 107 to regulate flow in the
first plurality of flow channels 105. First control channel 109 can
be actuated by a first inlet 111. A second control channel 106 can
control valves 104 to regulate flow in the second plurality of flow
channels 102. Second control channel 106 can be actuated by a
second inlet 108. The membrane or segment can be deflected into or
retracted from the flow channels with which the control channel is
associated by applying an actuation force to the control channels.
By controlling the degree to which the membrane or segment is
deflected into or retracted out from the flow channel, solution
flow can be slowed or entirely blocked through the flow channel.
Using combinations of control and flow channels, different types of
valves and pumps can be formed for regulating solution flow.
[0014] In various embodiments, the exemplary microfluidic devices
can further include guard channels in a guard layer to reduce
evaporation of samples and reagents. The guard channels can be
formed in a layer of elastomer that overlays the flow channels
and/or reaction sites. In an exemplary embodiment, a light blocking
dye can be included in the solution to reduce noise in optical
detection. Similar to the control channels, the guard channels can
be separated from the underlying flow channels and/or reaction
sites by a membrane or segment of elastomeric material. Unlike
control channels, however, the guard channels can be considerably
smaller in cross-sectional area.
[0015] The guard channels can be designed to be pressurized to
allow a solution, such as water, to flow into the guard channel.
For example, the guard channels can be used to perform thermal
cycling for the flow channels and/or reaction sites. In an
exemplary embodiment, the thermal cycling can be performed using
the guard channels by pumping a hot or cold liquid, such as water
or ethylene glycol. In various embodiments, the guard channels can
be configured, for example, overlay and/or underlie the flow
channels and/or reaction sites.
[0016] Exemplary microfluidic devices can be formed of elastomeric
materials by, for example, single and/or multilayer soft
lithography (MSL) techniques and/or sacrificial-layer encapsulation
methods. In various embodiments, the fluid (flow) channels can be
formed of an elastomer and/or a coating disposed on the elastomer,
where the coating includes silicon. In various other embodiments,
the fluid channels can further include a coating to avoid
degradation of, for example, reference dye 6-carboxy-X-rhodamine
(ROX). To achieve a desired optical or thermal property, the fluid
channels can be formed of, for example, polydimethylsiloxane (PDMS)
doped with, for example, carbon, TiO.sub.2 and/or ZnO.sub.2.
[0017] Operation of an exemplary microfluidic device will now be
discussed with reference back to FIG. 1 and microfluidic device 100
including 49 first fluid channels and 49 second fluid channels. One
of 49 primers can be introduced into respective ones of the 49
first fluid channels 105. The primers can mix with the samples at
each of the 2401 reaction sites 130. In various embodiments,
microfluidic device can be coupled to a thermocycler in order to
undergo thermal cycling, for example, using the guard channels.
[0018] According to various other embodiments, one or more reagents
can be deposited at the reaction sites 130 during fabrication of
the exemplary microfluidic devices. This can result in a reduction
in the number of input and outputs. For example, in an embodiment,
a bead can be provided in each of the reaction sites. The bead can
be preloaded with a primer, e.g., a DNA primer. After a desired
reaction using the primer, the flow channels and valve system can
be used to wash the reaction site prior to a next desired
reaction.
[0019] Reaction sites (e.g., 130 in FIG. 1) can be monitored using
a variety of detection systems including, for example, optical
detection systems. Because the exemplary microfluidic devices can
be made of elastomeric materials that are relatively optically
transparent, optical detection can occur at the reaction site
itself (e.g., at the intersection of flow channels in a matrix
design or at the blind end of a flow channel). Detection can be
accomplished using detectors that are incorporated into the device
or that are separate from the device but aligned with the reaction
sites. In various embodiments, the reaction sites can include a
molded lens to aid optical detection. The molded lens can be formed
of, e.g., one or more of a glass, a cyclo-olefin polymer (COP), a
cyclo-olefin copolymer (COC), a plastic, and a polycarbonate. In
various embodiments, fluorescence polarizing anisotropy measurement
can be made using a polarizing filter.
[0020] For example, FIG. 2 shows an exemplary system for collecting
optical signals from the reaction sites of the microfluidic
channels in accordance with the present teachings. As shown, a
control layer can be overlaid on top of a flow layer. The flow
layer can include various flow channels intersecting various
reaction sites, for example, one or more of the M.times.N reaction
sites 130 in FIG. 1. The control layer can include a plurality of
apertures having a medium, such as air or water, with a refractive
index of n1, formed in a bulk material (e.g., the transparent
material such as PDMS used for the control layer as described
above) having a refractive index of n2. The refractive index n2 of
the bulk material is generally greater than n1 of the medium in the
closest neighboring apertures. In an exemplary embodiment, the
control layer can be formed over the flow layer having reaction
sites aligned underneath the bulk material of the control layer.
During optical detection, a total internal reflection can occur to
confine ("pipe") light in the area of the bulk material and the
aligned respective reaction sites, defined by the closest
neighboring apertures. The collection efficiency can increase due
to the light confinement. In various embodiments, guard layers
having the guard channels can be configured to overlay and/or
underlie the microfluidic system shown in FIG. 2. For example, the
guard layer can be configured under the flow layer for a thermal
cycling.
[0021] While the invention has been described with reference to the
exemplary embodiments thereof, those skilled in the art will be
able to make various modifications to the described embodiments
without departing from the true spirit and scope. The terms and
descriptions used herein are set forth by way of illustration only
and are not meant as limitations. In particular, although the
method has been described by examples, the steps of the method may
be performed in a different order than illustrated or
simultaneously. Those skilled in the art will recognize that these
and other variations are possible within the spirit and scope as
defined in the following claims and their equivalents.
* * * * *