Small volume fluid devices

Abstract

The present disclosure provides a fluidic device. The fluidic device includes: a) a first bondable polymer layer having a substantially planar first major surface; b) a second polymer layer having a substantially planar first major surface; and c) a hydrophilic mask material disposed on a first portion of the first major surface of the first bondable polymer layer. The surface of the hydrophilic mask material exhibits an advancing contact angle with water of less than 90 degrees. The second portion of the first major surface of the first bondable polymer layer is bonded to the first portion of the first major surface of the second polymer layer. The hydrophilic mask material and the second portion of the first major surface of the second polymer layer are in direct contact with each other at at least one point. An open volume is defined by an interstitial space located between the hydrophilic mask material and the second portion of the first major surface of the second polymer layer. The open volume includes two or more openings, at least one of the openings being located at an edge of the first bondable polymer layer. The fluidic device can be formed to have a small volume for use as a precision fluidic device, such as a blood glucose test strip.

Description

[Technical field]

[0001] FIELD OF THE DISCLOSURE The present disclosure relates generally to fluidic devices for use with small fluid volumes. [Background technology]

[0002] Currently, die cutting and rotary conversion processes are often utilized for the manufacture of fluidic devices used in diagnostic and wearable devices. These processes are limited in their ability to manufacture small, complex structures and often require multiple individual film structures that are expensive and difficult to assemble. For example, a common approach to form a fluidic device chamber is to cut a small notch from a double-coated tape, laminate the tape to a bottom layer with the notch aligned over a sensor, and then laminate a hydrophilic cover film to form the top of the chamber. However, there are practical limitations to die cutting small features from tape, making it difficult to reduce the required sample volume to less than about 1 microliter. The volume of the chamber is defined by the thickness of the double-coated tape, requiring precise caliper control that is difficult to achieve with adhesive application processes. Furthermore, thin layers of adhesive tend to have lower adhesive strength than thicker layers. Also, using thin or ultra-thin films carries the risk of the film stretching or breaking during handling in the manufacture of fluidic devices. In addition to the challenges associated with fluidic device assembly, there are also material issues associated with utilizing double-coated tape to form capillary features. For example, it is difficult to make sidewalls formed by die cutting a tape hydrophilic, and therefore the surface energy of the cover film must be very high to induce spontaneous capillary action of aqueous samples such as body fluids. Summary of the Invention

[0003] In a first aspect, the present disclosure provides a fluidic device. The fluidic device includes: a) a first bondable polymer layer having a substantially planar first major surface; b) a second polymer layer having a substantially planar first major surface; and c) a hydrophilic mask material disposed on a first portion of the first major surface of the first bondable polymer layer. The surface of the hydrophilic mask material exhibits an advancing contact angle with water of less than 90 degrees. The second portion of the first major surface of the first bondable polymer layer is bonded to the first portion of the first major surface of the second polymer layer. The hydrophilic mask material and the second portion of the first major surface of the second polymer layer are in direct contact with each other at at least one point. The open volume is defined by a gap space located between the hydrophilic mask material and the second portion of the first major surface of the second polymer layer. The open volume includes two or more openings, at least one of which is located at an edge of the first bondable polymer layer.

[0004] It has been discovered that by bonding selected portions of two (e.g., substantially) planar layers and utilizing the interstitial space between one or more unbonded (e.g., hydrophilic) portions for fluid flow, it is possible to prepare a fluidic device for use with small volumes of fluid. This provides at least one advantageous property of increased performance by using smaller volumes of sample with greater precision than can be achieved by current manufacturing methods, as well as by not requiring the formation of cavities in the device. The fluidic device may be formed by a simple process, which reduces the number of input materials required, for example, compared to die cutting and rotary conversion processes.

[0005] Fluidic devices according to the present disclosure do not require cavities and therefore do not require (e.g. vertical) sidewalls, eliminating geometrical complexity compared to articles or devices that include cavities with sidewalls. Furthermore, these fluidic devices allow for the transport of much smaller volumes of liquid than current commercially available designs, i.e., interstitial transport between two (substantially) flat surfaces.

[0006] The above summary of the present disclosure is not intended to describe each disclosed embodiment or every implementation of the present disclosure. The following description more particularly illustrates exemplary embodiments. In several places throughout this application, guidance is provided through lists of examples, which examples can be used in various combinations. In each instance, the recited list serves only as a representative group and should not be interpreted as an exclusive list. [Brief description of the drawings]

[0007] [Figure 1A] 1 is an exploded generalized schematic diagram of an exemplary fluidic device. [Figure 1B] FIG. 1B is a generalized schematic diagram of a cross-section of a portion of the exemplary fluidic device of FIG. 1A. [Figure 1C] 1B is a generalized schematic diagram of another cross-section of a portion of the exemplary fluidic device of FIG. 1A. [Figure 2A] 1 is a stereomicroscope image of a portion of an exemplary fluidic device prior to contact with a fluid. [Figure 2B] 2B is a stereomicroscope image of a portion of the exemplary fluidic device of FIG. 2A after 0.5 seconds of contact with the fluid. [Figure 2C] 2B is a stereomicroscope image of a portion of the exemplary fluidic device of FIG. 2A after 1 second of contact with the fluid. [Diagram 3] FIG. 2 is a generalized schematic diagram of a second polymer layer including a detector having electrodes. [Figure 4A] 1 is a photograph of a tape containing three different patterned masks according to the present disclosure. [Figure 4B] 1 is a photograph of the sample of Example 1 prior to cutting the exemplary fluidic device from the remainder of the sample according to the present disclosure. [Figure 4C] 1 is a stereomicroscope image of a portion of the fluidic device of Example 1 prior to contact with a fluid. [Figure 4D] 1 is a stereomicroscope image of a portion of the fluidic device of Example 1 after 1.685 seconds of contact with the fluid. [Figure 4E] 1 is a stereomicroscope image of a portion of the fluidic device of Example 1 after 3.370 seconds of contact with the fluid. [Figure 5A] 13 is a photograph of the sample of Example 2 prior to cutting the exemplary fluidic device from the remainder of the sample according to the present disclosure. [Figure 5B] 1 is a stereomicroscope image of a portion of the fluidic device of Example 2 0.062 seconds after contact with the fluid. [Figure 5C] 1 is a stereomicroscope image of a portion of the fluidic device of Example 2 after 3.577 seconds of contact with the fluid. [Figure 5D] 1 is a stereomicroscope image of a portion of the fluidic device of Example 2 after 4.555 seconds of contact with the fluid. [Figure 5E] 1 is a stereomicroscope image of a portion of the fluidic device of Example 2 after 7.051 seconds of contact with the fluid. [Figure 6A] 13 is a photograph of the sample of Example 3 prior to cutting the exemplary fluidic device from the remainder of the sample according to the present disclosure. [Figure 6B] 13 is a stereomicroscope image of a portion of the fluidic device of Example 3 after 1.841 seconds of contact with the fluid. [Figure 6C] 13 is a stereomicroscope image of a portion of the fluidic device of Example 3 after 1.934 seconds of contact with the fluid. [Figure 6D] 13 is a stereomicroscope image of a portion of the fluidic device of Example 3 after 2.4021 seconds of contact with the fluid.

[0008] The above-identified Figures illustrate several embodiments of the present disclosure; however, other embodiments are contemplated as described herein. The drawings are not necessarily drawn to scale. In all cases, this disclosure presents the present invention by way of representation and not limitation. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] As used herein, the term "essentially free" in the context of a composition that is essentially free of a component refers to a composition that contains less than 1 weight percent (wt.%), 0.5 wt.% or less, 0.25 wt.% or less, 0.1 wt.% or less, 0.05 wt.% or less, 0.001 wt.% or less, or 0.0001 wt.% or less of a component based on the total weight of the composition. The term "essentially free" in the context of a feature of a structure (e.g., the surface of a layer) refers to a structure that has less than 5 area %, 4 area % or less, 3 area % or less, 2 area % or less, or 1 area % or less of the component based on the total area of ​​the structure.

[0010] As used herein, the term "polymer" refers to containing at least one polymer.

[0011] As used herein, the term "bondable" refers to materials (e.g., layers) that, after bonding, have an lap shear of at least 1 megapascal (MPa) or 2 MPa or greater, measured according to ASTM D-1002-94 at 23-25° C. Pressure sensitive adhesives and thermally bondable materials are each encompassed by the term "bondable."

[0012] As used herein, the term "thermally bondable" refers to a material (e.g., a layer) that forms a bond to one or more surfaces when heated, and the formed bond can be released upon subsequent heating. In contrast to pressure-sensitive adhesives, thermally bondable materials generally have insufficient tack to bond to substrates at room temperature. Unlike thermosetting materials, the bonds formed by thermally bondable materials are generally reversible.

[0013] As used herein, the term "pressure sensitive adhesive" refers to a material having properties including: (1) strong and permanent tack, (2) adhesion with no more than finger pressure, (3) sufficient ability to hold on the substrate, and (4) sufficient cohesion to remove cleanly from the substrate. Materials that have been found to perform well as PSAs include polymers designed and formulated to exhibit the necessary viscoelastic properties to provide the desired balance of tack, peel adhesion, and shear retention. PSAs are characterized as being normally tacky at room temperature. Materials that are simply tacky or adhere to a surface do not constitute a PSA. The term PSA encompasses materials with additional viscoelastic properties. PSAs are adhesives that meet the Dahlquist criteria for tack, which is that they have a shear storage modulus typically greater than 3×10 measured at 25° C. and 1 Hertz (6.28 radians / second). 5 Pa (300 kPa) or less. PSA typically exhibits adhesion, cohesion, compliance, and elasticity at room temperature. As used herein, the term "cavity" refers to an empty space defined by at least one wall of a (e.g., solid) object.

[0014] As used herein, the term "chamber" refers to a cavity surrounded by at least one additional wall.

[0015] As used herein, the term "channel" refers to a passageway that allows gas or liquid to exit a fluidic device.

[0016] As used herein, the term "dimensional stability" refers to the ability of a material (eg, an article or polymer layer) to maintain its size and shape even under a variety of environmental conditions and strains.

[0017] As used herein, the “glass transition temperature” (T g The term T ) refers to the transition of a polymer from a glassy to a rubbery state and can be measured using differential scanning calorimetry (DSC), for example at a heating rate of 10 °C / min in a nitrogen stream.g When a reference is made to T, it refers to the T of the homopolymer of that monomer. g The homopolymer is T g The molecular weight must be high enough so that the T of the homopolymer reaches a limiting value. g It is generally recognized that increases with increasing molecular weight up to a limiting value. Homopolymers are also susceptible to water, residual monomers, solvents, and T g It is understood that the DSC is substantially free of other contaminants that may affect the results. A suitable DSC method and analysis mode is as described in Matsumoto, A. et. al., J. Polym. Sci. A., Polym. Chem. 1993, vol. 31, pp. 2531-2539.

[0018] As used herein, the term "Vicat softening temperature" of a polymer refers to the determination of the softening point of a material that does not have a distinct melting point. It is taken as the temperature at which a test specimen is penetrated by a flat-tipped needle to a depth of 1 mm under a specified load.

[0019] As used herein, the term "hydrophilic" refers to a surface that is wetted by aqueous solutions and does not indicate whether the material absorbs the aqueous solution. "Wetting" means that the surface exhibits an advancing (maximum) water contact angle of less than 90°, preferably 45° or less. As used herein, the term "hydrophobic" refers to a surface that exhibits an advancing water contact angle of 90° or more.

[0020] As used herein, the term "fiducial" refers to a structure or mark that provides a fixed basis for comparison.

[0021] As used herein, "curing" refers to curing or partially curing a composition by any mechanism, for example, heat, light, radiation, electron beam, microwave, chemical reaction, or a combination thereof. As used herein, the term "curable" refers to a material that can be cured or solidified, for example, by heating to remove solvent, by heating to cause polymerization, chemical crosslinking, radiation-induced polymerization or crosslinking, etc. As used herein, "cured" refers to a material or composition that has been cured or partially cured (e.g., polymerized or crosslinked) by curing.

[0022] As used herein, "surface roughness" refers to the smoothness of a material surface and is defined as "R a ", which refers to the average surface roughness and is defined as the integral of the absolute value of the distance from the mean height. The mean height is the arithmetic mean of the height profile of the surface. The function z(x) refers to the difference between the height at position x and the mean height measured over the evaluation length l.

[0023]

number

[0024]

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[0025]

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[0026] Height can be measured using an optical profilometer (eg, a Wyko NT3300 optical profilometer manufactured by Veeco Instruments Inc., Plainview, New Jersey).

[0027] As used herein, "substantially planar" with respect to a layer means that the surface of the layer is essentially free of recesses and / or protrusions extending above and / or below the plane of the layer, and the recesses and / or protrusions have a depth or height of 5 micrometers (μm), 4.75 μm, 4.5 μm, 4.25 μm, 4 μm, 3.75 μm, 3.5 μm, 3.25 μm, 3 μm, 2.75 μm, 2.5 μm, 2.25 μm, 2 μm, 1.75 μm, 1.5 μm, 1.25 μm, 1 μm, 750 nm, 600 nm, 500 nm, 400 nm, greater than 300 nm, or greater than 200 nm. Typically, the recesses and / or protrusions have a depth or height of 5 nm or more, 10 nm, 15 nm, 20 nm, 25 nm, 30 nm, 40 nm, 50 nm, 75 nm, 100 nm, 125 nm, or 150 nm or more. In some cases, the deviation from planarity is caused by the thickness of the hydrophilic mask. Typically, the protrusions on the surface lack a designed pattern, but tend to be rather random. The depth or height of the recesses or protrusions present on the layer surface can be measured using a confocal microscope.

[0028] As used herein, "thermoplastic" refers to a polymer that flows when heated sufficiently above its glass transition point and becomes solid when cooled.

[0029] As used herein, "thermoset" refers to a polymer that becomes permanently hardened upon curing and does not flow upon subsequent application of heat. Thermoset polymers are typically crosslinked polymers.

[0030] As used herein, "transparent" refers to a material (e.g., a layer) that has at least 50% transmission, 70% transmission, or optionally greater than 90% transmission over at least the 400 nanometer (nm) to 700 nm portion of the visible light spectrum.

[0031] The words "preferred" and "preferably" refer to embodiments of the present disclosure that may provide certain benefits, under particular circumstances. However, other embodiments may also be preferred, under the same or other circumstances. Furthermore, the recitation of one or more preferred embodiments does not imply that other embodiments are not useful, nor is it intended to exclude other embodiments from the scope of the present disclosure.

[0032] In this application, terms such as "a," "an," and "the" are not intended to refer to a singular entity only, but include a general class of which a particular example may be used for illustration. The terms "a," "an," and "the" are used interchangeably with the term "at least one." The phrases "at least one of" and "comprising at least one of," followed by a list, refer to any one of the items in the list, and any combination of two or more items in the list.

[0033] As used herein, the term "or" is generally used in its ordinary sense, including "and / or," unless the content clearly dictates otherwise. The term "and / or" refers to one or all of the listed elements or a combination of any two or more of the listed elements.

[0034] Also, all numbers herein are assumed to be modified by the term "about," and preferably by the term "exactly." When used herein in connection with a measured quantity, the term "about" refers to the variation in the measured quantity that would be expected by one of ordinary skill in the art making the measurement and exercising a level of care commensurate with the purpose of the measurement and the precision of the measuring device used.

[0035] The term "generally," when used herein as a modifier to a characteristic or attribute, means that the characteristic or attribute is readily recognizable by one of ordinary skill in the art, but does not require absolute precision or perfect agreement (e.g., within + / - 20% for quantifiable characteristics), unless otherwise specifically defined. The term "substantially," unless otherwise specifically defined, means a high degree of approximation (e.g., within + / - 10% for quantifiable characteristics), but again does not require absolute precision or perfect agreement. Terms such as same, equal, uniform, constant, exact, etc., are understood to be within normal tolerances or measurement errors applicable to a particular situation, rather than requiring absolute precision or perfect agreement.

[0036] Fluidic devices according to at least certain embodiments of the present disclosure provide multi-layered, melt-bondable, spontaneous capillary microfluidic articles that may be useful, for example, for liquid sample acquisition. Suitable applications include, for example, bodily fluid acquisition for diagnostic devices (e.g., blood glucose strips) and medical wearables (e.g., sweat sensors). For example, blood glucose test strips are a type of disposable point-of-care sensor designed to analyze a small amount of blood, for example, from a stick on a person's finger. The strips traditionally include a bottom sensor layer laminated to multiple film layers configured to form a small chamber for blood to enter the strip and be exposed to the sensor chemicals.

[0037] It has been discovered that a molding process is capable of producing planar polymer layers with bondable regions to overcome at least one limitation of current methods of making fluidic devices. The bonding forms an airtight seal between the polymer layers, but the hydrophilic patterned regions do not bond. It has also been found that, for example, during thermal bonding, the molten polymer does not break through the hydrophilic patterned regions to bond in undesirable areas. Advantageously, the bonding process can be adapted to minimize deactivation of any sensor chemicals (e.g., reagents) present while achieving high bond strength. The incorporation of these features in a structure according to at least certain embodiments of the present disclosure simplifies device assembly by reducing the number of input materials required to form a single mechanically robust fluidic device.

[0038] In a first aspect, the present disclosure provides a fluidic device, the fluidic device comprising: a) a first bondable polymer layer having a first major surface that is substantially planar; b) a second polymer layer having a first major surface that is substantially planar; and c) a hydrophilic mask material disposed on a first portion of the first major surface of the first bondable polymer layer, wherein a surface of the hydrophilic mask material exhibits an advancing contact angle with water of less than 90 degrees; A second portion of the first major surface of the first bondable polymer layer is bonded to the first portion of the first major surface of the second polymer layer, the hydrophilic mask material and the second portion of the first major surface of the second polymer layer are in direct contact with each other at at least one point, an open volume is defined by an interstitial space located between the hydrophilic mask material and the second portion of the first major surface of the second polymer layer, and the open volume includes two or more openings, at least one of the openings is located at an edge of the first bondable polymer layer. Typically, the interstitial space comprises a volume of 450 nanoliters, 400 nanoliters, 350 nanoliters, 300 nanoliters, or even 250 nanoliters or less, and 0.5 nanoliters or more, 1 nanoliter, 2 nanoliters, 5 nanoliters, 7 nanoliters, 10 nanoliters, 15 nanoliters, 20 nanoliters, 25 nanoliters, 30 nanoliters, 35 nanoliters, 40 nanoliters, 45 nanoliters, 50 nanoliters, 55 nanoliters, 60 nanoliters, 70 nanoliters, 80 nanoliters, 90 nanoliters, or 100 nanoliters or more, or 500 nanoliters or less per square centimeter of the first portion of the first major surface of the first bondable polymer layer. This is advantageous in allowing the use of much smaller fluid samples with fluidic devices according to the present disclosure than devices that include cavities through which the fluid can flow.

[0039] 1A-1B, there are provided general schematic diagrams of an exploded view and a cross-sectional view, respectively, of a fluidic device 100. The fluidic device 100 comprises a first bondable polymer layer 110 having a substantially planar first major surface 112 and a hydrophilic mask material 114 disposed on a first portion 116 of the first major surface 112 of the first bondable polymer layer 110. The fluidic device 100 further comprises a second polymer layer 120 having a substantially planar first major surface 122. A second portion 118 of the first major surface 112 of the first bondable polymer layer 110 is bonded 132 to a first portion 124 of the first major surface 122 of the second polymer layer 120.

[0040] In this embodiment, the first portion 116 of the first major surface 112 of the first bondable polymer layer 110 on which the hydrophilic mask material 114 is disposed is a continuous region extending from a first edge 111 of the first bondable polymer layer 110 to each of an opposing second edge 113 of the first bondable polymer layer 110 and a third edge 115 of the first bondable polymer layer 110 located between the first edge 111 and the second edge 113 of the first bondable polymer layer 110, as well as to an interface 190 between the first portion 116 and the second portion 118. Optionally, the first portion 116 extends along the entirety 119 of the third edge 115. For example, in this embodiment, the first portion 116 of the first major surface 112 has a continuous quadrilateral shape bounded by the interface 190, the first edge 111, the second edge 113, and the third edge 115.

[0041] 1C, a schematic diagram of a portion of a cross section of the fluidic device 100 is provided, in which the hydrophilic mask material 114 and the second portion 126 of the first major surface 122 of the second polymer layer 120 are in direct contact with each other at at least one point, in this case four points 140, 142, 144, 146. An open volume 130 is defined by an interstitial space located between the hydrophilic mask material 114 and the second portion 126 of the first major surface 122 of the second polymer layer 120 (see also FIG. 1B for such an open volume 130). The open volume 130 includes two or more openings 134, 136, at least one of which is located at an edge of the first bondable polymer layer 110 (any of the edges 111, 113, and / or 115 shown in FIG. 1A). Thus, there is no intimate contact between the hydrophilic mask material 114 and the second portion 126 of the first major surface 122 of the second polymer layer 120 throughout the entire non-bonded region (e.g., throughout the entire first portion 116 of the first bondable polymer layer 110), but rather contact at specific points within the region. In some embodiments of the fluidic device, there is a gap of up to 5 μm between the first edge of the first bondable polymer layer and the immediately adjacent first edge of the second polymer layer (see, e.g., openings 134 and / or 136 in FIG. 1C ).

[0042] In any fluidic device according to the present disclosure, at least one of a first portion of the first major surface of the first bondable polymer layer or a second portion of the first major surface of the second polymer layer has an average surface roughness (R a For example, the major surface may exhibit a thickness of 1 nm or more, 2 nm, 5 nm, 10 nm, 15 nm, 20 nm, 25 nm, 30 nm, 35 nm, 40 nm, 45 nm, 50 nm, 75 nm, 100 nm, 125 nm, 150 nm, 175 nm, 200 nm, 250 nm, 300 nm, 350 nm, 400 nm, 450 nm, 500 nm, 550 nm, 600 nm, 650 nm, 700 nm, 7 50 nm, 800 nm, 850 nm, 900 nm, or 1 nm or more; and an average surface roughness (R a 1C, the hydrophilic mask material 114 on both the first portion 116 of the first major surface 122 of the first bondable polymer layer 110 and the second portion 126 of the first major surface 112 of the second polymer layer 120 has a rough surface and may exhibit an average surface roughness (R a ) In some cases, at least one contact point between the hydrophilic mask material and the second portion of the first major surface occurs at a location of maximum height of the surface roughness, such as point 144 in FIG. 1C.

[0043] The first bondable polymer layer of the embodiment of FIG. 1A further comprises a fiducial mark 160, i.e. a mark of a predetermined shape located on the first major surface 112 of the first bondable polymer layer 110. The fiducial structure or mark advantageously provides a fiducial mark for improved alignment of the article during further manufacturing and / or processing steps. Optionally, the first bondable polymer layer, the second polymer layer, or both, comprise a fiducial structure or mark. In an embodiment, instead of a mark, a fiducial structure may be provided on the fluidic device. The fiducial structure may, for example, be a three-dimensional structure formed on the fluidic device (e.g., during formation of the first or second polymer layer).

[0044] In any fluidic device according to the present disclosure, a channel may be provided that connects a first portion of the first major surface of the first bondable polymer layer with at least one of the second major surface of the first bondable polymer layer or the second major surface of the second polymer layer. The channel is a passageway that allows gas or liquid to exit the fluidic device, and may help to wick fluid into the fluidic device, since displaced gas or liquid can easily exit (e.g., more) from the fluidic device through the channel. In the embodiment shown in Figures 1A and 1B, the channel 150 has a generally cylindrical shape. However, the shape is not particularly limited. For example, a generally cylindrical channel may be formed using laser drilling through at least one of the first bondable polymer layer 110 or the second polymer layer 120.

[0045] 2A-2C, microscopic images of a portion of an exemplary fluidic device of Example 4 (described below) are provided before contact with a fluid (FIG. 2A), after contact with a fluid for 0.5 seconds (FIG. 2B), and after contact with a fluid for 1 second (FIG. 2C). FIG. 2A provides an image of a portion of a fluidic device 200 having a first bondable polymer layer 210 having a first major surface (not shown) and a hydrophilic mask material (not shown) disposed on an opposing second major surface 217. The first bondable polymer layer 210 is bonded to a second polymer layer 220 at a second portion 218 of the first bondable polymer layer 210, but is not bonded at a first portion 216 of the first bondable polymer layer 210. In this embodiment, the first portion 216 is a continuous portion that extends completely along a first edge 211, along an opposing second edge 213, and along a third edge 215 located between the first edge 211 and the second edge 213. This configuration allows for air and / or liquid venting at any point along each of the edges during use of the fluidic device 200 .

[0046] A three microliter sample of human blood 295 was contacted with the third edge 215 of the fluidic device 200, and Figure 2B shows that one-half second after the time of contact, a portion of the blood sample has traveled a distance of at least 2000 micrometers from the third edge 215 into the fluidic device 200 (i.e., into the open volume formed by the interstitial space between the unbonded hydrophilic mask material and the second polymer layer 220). The distance traveled is provided by the presence of blood 295 and can be seen by the presence of a darker shade of grey, marked at one point along the leading edge of blood 295 by a bracket labeled 2211.38 μm. 2C shows that 1 second after the contact time, a portion of blood 295 has traveled the entire distance laterally through the open volume into the fluidic device 200, from the third edge 215 to the interface 290, where a first portion 216 of the first bondable polymer layer 210 (i.e., comprising the hydrophilic mask material) comes into contact with a second portion 218 of the first bondable polymer layer 210 (i.e., is bonded to the second polymer layer 220). The interface lies along the vertical line pointed to by the arrow in 290 and is marked by the bracket labeled 4648.05 μm.

[0047] Advantageously, the use of a hydrophilic mask material allows for the creation of complex fluidic designs that are not easily manufactured by microreplication, embossing, or die cutting. The designs or patterns are not particularly limited and can be configured in a variety of ways. For example, in any fluidic device according to the present disclosure, a first portion of a first major surface of a first bondable polymer layer on which the hydrophilic mask material is disposed may include: a) from a first portion of the third edge of the first bondable polymer layer, i) to at least one of the first edge or the second edge of the first bondable polymer layer, or ii) back to the third edge of the first bondable polymer layer at a location spaced from the first portion of the third edge; b) from the first portion of the second edge of the first bondable polymer layer i) to at least one of the first edge or the third edge of the first bondable polymer layer, or ii) back to the second edge of the first bondable polymer layer at a location spaced from the first portion of the second edge; or c) there is a pattern defining a fluid pathway from the first portion of the first edge of the first bondable polymer layer to i) at least one of the second edge or the third edge of the first bondable polymer layer, or ii) back to the first edge of the first bondable polymer layer at a location spaced from the first portion of the first edge.

[0048] Thus, referring again to FIG. 1A, a pattern (not shown) of hydrophilic mask material 114 may be applied to a first portion 116 of a first major surface 112 of a first bondable polymer layer 110 that defines a fluidic path beginning at a position along any one of the first edge 111, the second edge 113, or the third edge 115 to provide at least two openings in the fluidic device. Furthermore, the fluidic path may extend to a separate position on the same edge where it begins, or may extend to a position on either of the other two edges. There is no alignment between any pattern (e.g., deviations from planarity such as surface roughness) on the second polymer layer and the pattern of hydrophilic mask material. Some particularly suitable hydrophilic mask material patterns are shown in FIG. 4A and described in detail below.

[0049] Referring to Figure 4A, a photograph of a tape containing three different patterned masks 400, 500, and 600 is provided. In patterned mask 400, the pattern is designed such that a first portion of a first major surface of a first bondable polymer layer has a feature with a length at least 10 times greater than the width of the feature. Such a feature may be provided by an open area 403 (i.e., having a width of 1 mm and a length of 10 mm) connected to an open area 405 at a 90 degree angle. The pattern is designed such that fluid is wicked from one edge of the fluidic device to a different (e.g., adjacent) edge.

[0050] In the patterned mask 500, the pattern is designed such that the first portion of the first major surface of the first bondable polymer layer has a linear shape including straight portions. In other cases, linear shapes including curved portions or a combination of straight and curved portions are provided. The pattern is designed such that the fluid wicks from one edge of the fluidic device to a different (i.e., opposing) edge. In the patterned mask 600, the pattern has a rectangular design such that the first portion of the first major surface of the first polymer layer has essentially the same shape as in FIG. 2A (e.g., a continuous portion that extends completely along the first edge, along the opposing second edge, and along the third edge located between the first and second edges).

[0051] Suitable hydrophilic mask materials include, but are not limited to, for example, plasma deposited silicon / oxygen materials or diamond-like glass, nanostructures (such as those using the methods described in U.S. Pat. Nos. 8,634,146 and 10,134,566, each to David et al.), surfactants, polyesters, polyamides, polyurethanes, poly(vinyl alcohol), poly(alkylene glycol), poly(alkylene oxide), poly(vinylpyrrolidone), rubber elastomers, or any combination thereof.

[0052] To prepare a (bonded) fluidic device, the first bondable polymer layer may include, for example, but is not limited to, low density polyethylene, ethylene vinyl acetate, ethylene acrylic acid, polyurethane, copolymers of polyester and polyolefin, copolymers of polyurethane and aromatic poly(meth)acrylate, copolymers of polycaprolactone and polyurethane, or combinations thereof. One suitable commercially available polyurethane is available from Lubrizol (Wickliffe, OH) under the trade name "PEARLBOND 1160L". A suitable commercially available ethylene vinyl acetate (EVA) is available from The Dow Chemical Company under the trade name "DUPONT ELVAX 3180". A suitable commercially available ethylene acrylic acid is available from SK Global Chemical (Seoul South Korea) under the trade name "PRIMACOR 3330". Additionally, various additives, such as plasticizers, antioxidants, pigments, release agents, antistatic agents, etc., may be included in the first bondable polymer layer.

[0053] In any embodiment, the average thickness of the first bondable layer is 5 micrometers or more, 7.5 micrometers, 10 micrometers, 12.5 micrometers, 15 micrometers, 17.5 micrometers, or 20 micrometers or more, and 50 micrometers or less, 45 micrometers, 40 micrometers, 35 micrometers, 30 micrometers, or 25 micrometers or less. In other words, the first bondable polymer layer can have an average thickness of 5 micrometers to 50 micrometers. The average thickness can be determined by measuring the thickness at least 5 points located at least 0.5 millimeters apart from each other and taking the average of all of the measured thicknesses.

[0054] In some cases, suitable polymeric materials for the first bondable polymer layer include, but are not limited to, low density polyethylene, ethylene vinyl acetate, polyurethane, copolymers of polyester and polyolefin, copolymers of polyurethane and aromatic poly(meth)acrylate, copolymers of polycaprolactone and polyurethane, or combinations thereof. Additionally, various additives, such as plasticizers, antioxidants, pigments, release agents, antistatic agents, and the like, may be included in the first bondable polymer layer.

[0055] Suitable polymeric materials for the second polymer layer include, but are not limited to, polyolefins (e.g., high density polyethylene (HDPE), medium density polyethylene (MDPE), or low density polyethylene (LDPE)), polyesters, polyamides, poly(vinyl chloride), polyetheresters, polyimides, polyesteramides, polyacrylates, polyvinyl acetate, or hydrolyzed derivatives of polyvinyl acetate. In certain embodiments, polyolefins are preferred due to their excellent physical properties, ease of processing (e.g., replicating the surface of a tool), and typically low cost. Polyolefins are also generally tough, durable, and retain their shape well, making them easy to handle after the article is formed. In selected embodiments, the second polymeric layer comprises polyester polyethylene terephthalate (PET). One suitable commercially available PET is a 5 mil (127 micrometer) thick PET sheet sold under the trade designation "MELINEX 454" by Tekra (New Berlin, WI). A suitable commercially available LDPE is available from The Dow Chemical Company, Midland Michigan, under the trade designation "DOW 955I LDPE."

[0056] The surface of the second polymer layer may be subjected to a surface treatment to improve bonding with the first bondable polymer layer. Suitable surface treatments may include flame treatment, corona treatment, metal primer (e.g., a layer of metal such as gold), or chemical primer.

[0057] Preferably, the second polymer layer has a maximum thickness of 500 micrometers, 475 micrometers, 450 micrometers, 425 micrometers, 400 micrometers, 375 micrometers, 350 micrometers, 325 micrometers, 300 micrometers, 275 micrometers, 250 micrometers, 225 micrometers, 200 micrometers, or 175 micrometers and a minimum thickness of 50 micrometers, 75 micrometers, 100 micrometers, 125 micrometers, or 150 micrometers.

[0058] In certain embodiments, the first bondable polymer layer has a Vicat softening temperature (T g The Vicat softening temperature of the first bondable polymer layer is often at least 10% lower than the Vicat softening temperature of the second polymer layer, and is 15%, 20%, 25%, 30%, 35%, or at least 40% lower than the Vicat softening temperature of the second polymer layer. In certain embodiments, the second polymer layer has a Vicat softening temperature (T) of 150 degrees Celsius (° C.) or less, 145° C., 140° C., 130° C., 120° C., 115° C., or 110° C. or less, and 65° C. or more, 70° C., 75° C., 80° C., or 85° C. or more. g Using polymer layers having different Vicat softening temperatures can aid in thermally bonding the second polymer layer to the first bondable polymer layer while each polymer layer maintains its substantially flat first major surface.

[0059] In some embodiments, the first bondable polymer layer, the second polymer layer, or both, are transparent to visible light (as defined above). Providing one or more transparent layers may be advantageous in certain applications where a sample reaction may be optically detected through at least a portion of the article.

[0060] In preferred embodiments, the article is advantageously dimensionally stable at a temperature of 25 degrees Celsius (°C) with a strain of less than 50%, 40%, 30%, 20%, 15%, 10%, or less than 5%. As used herein, "strain" refers to the stretch ratio or elongation ratio. It is defined as the ratio between the final length l and the initial length L of a line of material in any particular direction. For example, 50% elongation = 1.5L. Dimensional stability helps resist deformation of the fluidic device as it is handled, reducing the possibility of damaging the structure before or during use.

[0061] Fluidic devices according to at least certain embodiments of the present disclosure can spontaneously and uniformly transport liquid (e.g., water, urine, blood, or other aqueous solutions) from a first opening contacted by the liquid toward at least a second opening along an open volume between the hydrophilic mask material and a second portion of the first major surface of the second polymer layer. This ability is often referred to as wicking. Two general factors that affect the ability of a layer to spontaneously transport liquid are (i) the structure or topography of the surface (e.g., capillarity, shape of the cavity), and (ii) the nature of the surface (e.g., surface energy). Because the first and second polymer layers are each substantially planar and directly adjacent to one another, designers can tailor the surface energy of the polymer layer surface on which the hydrophilic masking material is disposed to achieve a particular desired amount of fluid transport ability. To achieve wicking, the surface of that polymer layer must be capable of being "wet" by the liquid to be transported, which is achieved using a hydrophilic mask material. Generally, the wettability of a solid surface by a liquid is characterized by the contact angle that the liquid makes with the solid surface after being deposited on the horizontally positioned surface and allowed to settle thereon. This angle is sometimes referred to as the "static equilibrium contact angle" or simply "advancing contact angle" herein. As defined above, a material is hydrophilic if it has an advancing contact angle of less than 90 degrees.

[0062] Hydrophilicity may be achieved through one or more of material selection, additives included in the material, or surface treatment. Often, the hydrophilic mask material has an average thickness (e.g., of the material disposed on the first or second polymer layer) of 1 nm to 1 μm. For example, the hydrophilic mask material can have an average thickness of 1 nm or more, 2 nm, 5 nm, 10 nm, 15 nm, 20 nm, 25 nm, 30 nm, 35 nm, 40 nm, 45 nm, 50 nm, 75 nm, 100 nm, 125 nm, 150 nm, 175 nm, 200 nm, 250 nm, 300 nm, 350 nm, 400 nm, 450 nm, or 500 nm or more; and 1 μm or less, 950 nm, 900 nm, 850 nm, 800 nm, 750 nm, 700 nm, 650 nm, 600 nm, 550 nm, 500 nm, 450 nm, 400 nm, 350 nm, 300 nm, or 250 nm or less.

[0063] In some embodiments, the hydrophilic mask material comprises a surfactant, a surface structure, a surface treatment, a hydrophilic polymer, or a combination thereof. Suitable surfactants include, for example, but are not limited to, C8-C18 alkane sulfonates; C8-C18 secondary alkane sulfonates; alkyl benzene sulfonates; C8-C18 alkyl sulfates; alkyl ether sulfates; sodium laureth 4 sulfate; sodium laureth 8 sulfate; dioctyl sulfosuccinic acid sodium salt; lauroyl lacylates; stearoyl lactylates; or any combination thereof. The one or more surfactants can be applied by conventional methods, for example, by wiping a coating of the surfactant on the surface of the second polymer layer and allowing the coating to dry. Suitable surface structures include discontinuous coatings that include pillars and interstitial spaces between the pillars. Nanopillars can be formed using methods described, for example, in U.S. Pat. Nos. 8,634,146 and 10,134,566 (each to David et al.). Suitable surface treatments include hydrophilic coatings including plasma-deposited silicon / oxygen materials and / or diamond-like glass (DLG) materials. Plasma deposition of silicon / oxygen materials and DLG materials, respectively, is described, for example, in WO 2007 / 075665 (Somasiri et al.). Further examples of suitable DLG materials are disclosed in U.S. Pat. Nos. 6,696,157 (David et al.), 6,881,538 (Haddad et al.), and 8,664,323 (Iyer et al.). Suitable hydrophilic polymers include, but are not limited to, for example, polyesters, polyamides, polyurethanes, poly(vinyl alcohols), poly(alkylene glycols), poly(alkylene oxides), poly(vinylpyrrolidones), rubber elastomers, or any combination thereof.

[0064] In any fluidic device according to the present disclosure, at least one of the first bondable polymer layer or the second polymer layer may include a reagent, for example, a reagent disposed on a major surface of the layer. The reagent is preferably configured to react with the sample and provide at least one response selected from electrochemical, optical, fluorescent, and / or chemiluminescent response types. Some suitable reagents include, but are not limited to, for example, fluorogenic or chromogenic indicators, electrochemical reagents, agglutination reagents, analyte-specific binding agents, amplification agents such as enzymes and catalysts, photochromic agents, dielectric compositions, analyte-specific reporters such as enzyme-linked antibody probes, DNA probes, RNA probes, fluorescent or phosphorescent beads, or any combination thereof. When a layer includes a reagent, the layer often also includes a detector. For example, referring to FIG. 3, a generalized schematic top view of a second polymer layer 320 including a reagent (not shown) and including a detector 370 disposed on a first major surface 322 of the second polymer layer 320 is shown. In selected embodiments, the detector 370 includes an electrode 380 that is also disposed on the first major surface 122 of the second polymer layer 320. In such embodiments, the open volume of the fluidic device (e.g., over the first portion 324 of the second polymer layer 320) is in fluid communication with the electrode. Alternatively, any such detector and electrode may be provided on the first bondable polymer layer. For example, in a blood glucose test strip device application, blood from a finger prick enters an opening in the fluidic device and contacts a reagent, and a response from a reaction between the reagent and the blood is measured by the detector.

[0065] method A fluidic device according to the present disclosure may be formed by a method including: a) applying a hydrophilic mask material to a first portion of a first major surface of a first polymer; b) disposing a second polymer onto the first polymer; and c) applying compression to the first polymer and the second polymer at an elevated temperature to bond a second portion of the first major surface of the first bondable polymer layer to the second polymer layer to form a fluidic device.

[0066] Often, the first polymer and the second polymer are bonded together (in step c) using a tool having a substantially flat major surface. The hydrophilic mask material is typically applied by placing a mask over the second portion of the first major surface of the first bondable polymer layer to prevent application of the hydrophilic mask material, followed by depositing the hydrophilic mask material over the first portion of the first major surface of the first bondable polymer layer. Masks are known to those skilled in the art to aid in covering only the desired areas of the surface with the material by blocking areas where it is not desired to apply the hydrophilic mask material. Alternatively, the hydrophilic mask material may be applied by printing the material in a pattern, for example using a flexographic printing process.

[0067] The first polymer and the second polymer are as described in detail above with respect to the materials for the first bondable polymer layer and the second polymer layer of the fluidic device, respectively. In some embodiments, the first polymer and the second polymer are provided independently in the form of a sheet (e.g., a layer) or as particulates (e.g., pellets). Elevated temperatures used in certain embodiments of the method are 300 degrees Fahrenheit (°F) or less, 290°F, 285°F, 280°F, 275°F, 270°F, 265°F, 260°F, 255°F, 250°F, 245°F, 240°F, 235°F, 230°F, or 225°F or less; and 150°F or more, 155°F, 160°F, 165°F, 170°F, 175°F, 180°F, 185°F, 190°F, 195°F, or 200°F or more. Applying compression optionally further includes cooling the fluidic device after exposure to the elevated temperature, such as by allowing it to cool by exposure to ambient temperature or by actively cooling the tool and / or the fluidic article.

[0068] In some embodiments, the method includes applying compression for up to 10 minutes, 9 minutes, 8 minutes, 7 minutes, 6 minutes, 5 minutes, or 4 minutes, and for 0.5 minutes or more, 1 minute, 2 minutes, or 3 minutes or more. The method may include applying compression across the area with up to 15,000 pounds, 14,000 pounds, 13,000 pounds, 12,500 pounds, 12,000 pounds, 11,000 pounds, 10,000 pounds, 9,000 pounds, 8,000 pounds, or 7,500 pounds, and up to 3,000 pounds, 3,500 pounds, 4,000 pounds, 4,500 pounds, 5,000 pounds, 5,500 pounds, 6,000 pounds, 6,500 pounds, or 7,000 pounds of pressure. For example, 10,000 pounds compressed over an area of ​​81 square inches (522.58 square centimeters) results in 12 psi (0.083 megapascals).

[0069] In selected embodiments, the method further comprises subjecting the fluidic device to post-curing, which can be carried out using actinic radiation, such as UV radiation, electron beam radiation, visible radiation, or any combination thereof. Those skilled in the art can select a radiation source and wavelength range suitable for a particular application without undue experimentation. So-called post-curing ovens, which combine UV radiation with thermal energy, are particularly well suited for use in the post-curing process. In general, post-curing improves the mechanical properties and stability of the article compared to the same article that is not post-cured.

[0070] At least certain embodiments of the method of the present invention unexpectedly provide a multi-layer spontaneous capillary microfluidic device having a small open volume between substantially flat surfaces. In contrast, WO 2020 / 261086 (Halverson et al.) describes the incorporation of cavities formed in the article, which are not required in the present fluidic device to achieve capillary flow of fluid through the device. Additionally, PCT Publication WO 98 / 45693 (Soane et al.) and U.S. Pat. No. 7,553,393 (Derand et al.) each describe the use of a heat-sealable cover layer to a microfluidic structure formed in a second film. However, these documents do not address the situation where the thermal bond is located on the cavity side (e.g., the channel of the microfluidic structure), as required for lamination to a detection (e.g., sensor) layer. U.S. Pat. No. 5,798,031 (Charlton et al.) and U.S. Pat. No. 8,617,367 (Edelbrock et al.) each describe heat-forming features in a thermally bondable film for subsequent lamination to a detection layer. In these examples, the film is oriented with the thermally bondable layer facing away from the thermoforming tool to prevent the thermally bondable layer from adhering to the tool surface during thermoforming. The result of this orientation requirement is the production of a film with a Z-axis profile, which is mechanically less robust than an article having at least one flat major surface.

[0071] Best Mode for Carrying Out the Invention In a first embodiment, the present disclosure provides a fluidic device. The fluidic device includes: a) a first bondable polymer layer having a substantially planar first major surface; b) a second polymer layer having a substantially planar first major surface; and c) a hydrophilic mask material disposed on a first portion of the first major surface of the first bondable polymer layer. The surface of the hydrophilic mask material exhibits an advancing contact angle with water of less than 90 degrees. The second portion of the first major surface of the first bondable polymer layer is bonded to the first portion of the first major surface of the second polymer layer. The hydrophilic mask material and the second portion of the first major surface of the second polymer layer are in direct contact with each other at at least one point. An open volume is defined by a gap space located between the hydrophilic mask material and the second portion of the first major surface of the second polymer layer. The open volume includes two or more openings, at least one of which is located at an edge of the first bondable polymer layer.

[0072] In a second embodiment, the present disclosure provides a fluidic device according to the first embodiment, wherein a first portion of the first major surface of the first bondable polymer layer on which the hydrophilic mask material is disposed is a continuous region extending from a first edge of the first bondable polymer layer to an opposing second edge of the first bondable polymer layer, and to a third edge of the first bondable polymer layer located between the first edge and the second edge of the first bondable polymer layer.

[0073] In a third embodiment, the present disclosure provides a fluidic device according to the second embodiment, wherein the first portion extends along the entire third edge.

[0074] In a fourth embodiment, the present disclosure provides a fluidic device according to the first embodiment, wherein a first portion of the first major surface of the first bondable polymer layer on which the hydrophilic mask material is disposed extends from a) a first portion of the third edge of the first bondable polymer layer, i) to at least one of the first edge or the second edge of the first bondable polymer layer, or ii) back to the third edge of the first bondable polymer layer at a location spaced from the first portion of the third edge, and b) from a first portion of the second edge of the first bondable polymer layer, A pattern that defines a fluid pathway i) to at least one of the first edge or the third edge of the first bondable polymer layer, or ii) back to the second edge of the first bondable polymer layer at a location spaced from the first portion of the second edge, or c) from the first portion of the first edge of the first bondable polymer layer to i) at least one of the second edge or the third edge of the first bondable polymer layer, or ii) back to the first edge of the first bondable polymer layer at a location spaced from the first portion of the first edge.

[0075] In a fifth embodiment, the present disclosure provides a fluidic device according to the fourth embodiment, wherein a first portion of the first major surface of the first bondable polymer layer and a second portion of the first major surface of the first bondable polymer layer interpenetrate each other.

[0076] In a sixth embodiment, the present disclosure provides a fluidic device according to the fourth or fifth embodiment, wherein a first portion of a first major surface of a first bondable polymer layer has a shape having a length that is at least 10 times greater than a width of the shape.

[0077] In a seventh embodiment, the present disclosure provides a fluidic device according to any of the fourth to sixth embodiments, wherein a first portion of the first major surface of the first bondable polymer layer has a linear shape including a straight portion, a curved portion, or a combination thereof.

[0078] In an eighth embodiment, the present disclosure provides a fluidic device according to any of the first to seventh embodiments, wherein the hydrophilic mask material comprises plasma deposited silicon / oxygen material or diamond-like glass, nanostructures, surfactants, polyesters, polyamides, polyurethanes, poly(vinyl alcohol), poly(alkylene glycol), poly(alkylene oxide), poly(vinylpyrrolidone), rubber elastomers, or combinations thereof.

[0079] In a ninth embodiment, the present disclosure provides a fluidic device according to any of the first to eighth embodiments, wherein the first bondable polymer layer comprises low density polyethylene, ethylene vinyl acetate, polyurethane, a copolymer of polyester and polyolefin, a copolymer of polyurethane and aromatic poly(meth)acrylate, a copolymer of polycaprolactone and polyurethane, or a combination thereof.

[0080] In a tenth embodiment, the present disclosure provides a fluidic device according to any of the first to ninth embodiments, wherein the second polymer layer comprises a polyolefin, a polyester, a polyamide, a poly(vinyl chloride), a polyetherester, a polyimide, a polyesteramide, a polyacrylate, a polyvinyl acetate, an ethylene acrylic acid adhesive, or a hydrolyzed derivative of polyvinyl acetate.

[0081] In an eleventh embodiment, the present disclosure provides a method for producing a bondable polymeric layer having a Vicat softening temperature (T g A fluidic device according to a tenth embodiment is provided, comprising:

[0082] In a twelfth embodiment, the present disclosure provides a fluidic device according to any of the first to eighth embodiments, wherein the second polymeric layer comprises a surface treatment comprising a layer of gold.

[0083] In a thirteenth embodiment, the present disclosure provides a fluidic device according to any of the first to twelfth embodiments, wherein at least one of the first bondable polymer layer or the second polymer layer comprises a reagent configured to react with a sample and provide a response selected from electrochemical, optical, fluorescent, chemiluminescent, or a combination thereof.

[0084] In a fourteenth embodiment, the present disclosure provides a fluidic device according to the thirteenth embodiment, wherein at least one of the first bondable polymer layer or the second polymer layer further comprises a detector.

[0085] In a fifteenth embodiment, the present disclosure provides a fluidic device according to the fourteenth embodiment, wherein the detector comprises an electrode arranged on a first main surface of the first polymer layer or the second polymer layer, and the open volume is in fluid communication with the electrode.

[0086] In a sixteenth embodiment, the present disclosure provides a fluidic device according to any of the first to fourteenth embodiments, wherein the interstitial space comprises a volume of 500 nanoliters or less per square centimeter of the first portion of the first major surface of the first bondable polymer layer.

[0087] In a seventeenth embodiment, the present disclosure provides a fluidic device according to any of the first to sixteenth embodiments, wherein the first bondable polymer layer, the second polymer layer, or both, further comprise a reference structure or mark.

[0088] In an eighteenth embodiment, the present disclosure provides a fluidic device according to any of the first to seventeenth embodiments, further comprising a channel connecting a first portion of the first major surface of the first bondable polymer layer to at least one of the second major surface of the first bondable polymer layer or the second major surface of the second polymer layer.

[0089] In a nineteenth embodiment, the present disclosure provides a method for producing a bondable polymeric layer comprising: forming a bondable polymeric layer on a substrate; and bonding the bondable polymeric layer to a substrate; and bonding the bondable polymeric layer to a substrate;a The present invention provides a fluidic device according to any one of the first to eighteenth embodiments, which shows a

[0090] In a twentieth embodiment, the present disclosure provides a fluidic device according to the nineteenth embodiment, wherein at least one contact point between the hydrophilic mask material and the second portion of the first major surface occurs at a location of maximum height of the surface roughness.

[0091] In a twenty-first embodiment, the present disclosure provides a fluidic device according to any of the first to twentieth embodiments, comprising a gap of up to 5 μm between a first edge of the first bondable polymer layer and a directly adjacent first edge of the second polymer layer.

[0092] In a twenty-second embodiment, the present disclosure provides a fluidic device according to any of the first to twenty-first embodiments, wherein the hydrophilic mask material has an average thickness of 1 nm to 1 μm. EXAMPLES

[0093] Objects and advantages of the present disclosure are further illustrated by the following examples, in which the particular materials and amounts thereof recited, as well as other conditions and details, should not be construed to unduly limit the disclosure. Unless otherwise indicated or apparent from the context, all parts, percentages, ratios, etc. in the examples and the remainder of the specification are by weight.

[0094] General procedure for preparation of fluidic devices The example fluidic devices were prepared with the bondable polymer layer component of the device being a two-layer polymer film having a 250 micrometer thick ZEONOR 1420R cyclic olefin polymer (Zeon Chemicals LP, Louisville, KY) backing layer and a 25 micrometer bondable layer of PRIMACOR 3330 polyethylene / acrylic acid copolymer (SK Global Chemical, Seoul, South Korea). The bondable polymer layer component was prepared by a bilayer extrusion process. Two single screw extruders were used to feed a 25 cm multi-manifold die. The extrusion process was performed horizontally into a nip between two rollers. The extruder conditions are listed in Table 1.

[0095] [Table 1]

[0096] The polymer layer component used in the example device was a 75 micrometer thick Melinex 454 polyester PET film (Tekra, New Berlin, WI) that was coated with a thin layer of gold (about 20 nanometers) using vacuum deposition. Gold was applied to one surface of the PET film by placing the film (5.1 cm x 5.1 cm section) in a vacuum sputtering chamber (Desk V Deposition Coater, Denton Vacuum, Moorestown, NJ) for 2 minutes at a power setting of 30 milliamps.

[0097] A hydrophilic mask coating having silanol and siloxane groups was applied to the bondable layer surface of the bondable polymer layer component using a parallel plate capacitively coupled plasma reactor as described in U.S. Pat. No. 6,696,157. Prior to placement in the reactor, a patterned mask template was applied onto the bondable surface so that the hydrophilic coating could be applied in a specific pattern. The mask template material was 3M 851 Th polyester / silicone tape (3M Company, St. Paul, MN), and each pattern was cut from the tape using a Muse laser cutter (Full Spectrum Laser Company, Las Vegas, NV). Individual patterns used in the examples are shown in FIG. 4A. A hand roller was used to apply the patterned mask template to the bondable surface.

[0098] The reactor chamber is 1.7 m 2The reactor had a central cylindrical powered electrode with a surface area of ​​1.3 Pa (2 mTorr). After placing the film on the powered electrode, the reactor chamber was pumped down to a base pressure of less than 1.3 Pa (2 mTorr). Oxygen and hexamethyldisiloxane (HMDSO) gases were flowed into the chamber at rates of 200 SCCM (standard cubic centimeters per minute) and 1000 SCCM, respectively. The treatment was carried out using a plasma-enhanced CVD method by coupling RF power to the reactor at a frequency of 13.56 MHz and an applied power of 7000 Watts. Treatment time was controlled by moving the film through the reaction zone at a speed of 30 feet / minute (914 cm / minute), resulting in an exposure time of approximately 10 seconds. After the initial treatment, the gas and power were turned off to the reactor chamber. The chamber was then pumped down to a base pressure of 1.3 Pa (2 mTorr). Oxygen gas was then flowed into the chamber at a flow rate of 1000 SCCM. The second treatment was carried out using plasma by coupling RF power into the reactor at a frequency of 13.56 MHz and an applied power of 5000 Watts. The treatment time was controlled by moving the film through the reaction zone at a speed of 30 ft / min (914 cm / min), resulting in an exposure time of approximately 10 seconds. At the end of this treatment time, the RF power and gas supply were stopped and the chamber was returned to atmospheric pressure. The patterned mask template was then removed to provide a hydrophilic mask coating on the bondable layer surface in the shape defined by the patterned mask template. The thickness of the deposited hydrophilic mask coating was approximately 20-50 nm.

[0099] The bondable polymer layer component and the polymer layer component were laminated together such that the surface of the bondable layer with the hydrophilic mask coating faced the gold-coated surface of the PET film. To laminate, the film stack was placed on a heated surface (110° C.) with the PET polymer layer in contact with the heated surface. After 30 seconds on the heated surface, a weighted roller (2.0 kg) was passed back and forth over the film stack three times. The resulting laminated sample was removed from the heated surface and allowed to cool to room temperature. Completed devices were cut from the laminated sample.

[0100] Example 1. The laminated sample 400b shown in FIG. 4B was prepared using the general procedure described above. A fluidic device 400c (FIG. 4C) (outer dimensions of 15 mm×8 mm) defined by the superimposed dotted line 407 in FIG. 4B was cut from the laminated sample 400b using a razor blade. The superimposed dotted line was added to the photographic image as a visual representation of the section cut from the laminated sample. The hydrophilic mask material region 414 formed an L-shaped channel with a first channel section of about 11 mm×2 mm extending from edge 411 and a narrower orthogonal channel section of about 4 mm×1 mm extending from the first section to a third edge 415.

[0101] A transfer pipette (2 mL graduation, Molecular Bio Products, Inc., San Diego CA) was used to bring a droplet of deionized water into contact with the hydrophilic material edge opening 411 (Figure 4C). After aspirating water into the pipette, pressure was applied to the pipette bulb to generate a hanging drop of approximately 10 microliters at the pipette tip. After the hanging drop was brought into contact with the edge opening, the advancing meniscus of water was monitored using a Zeiss Lumar V12 stereo microscope (Zeiss, Dublin, CA) (12X magnification) equipped with an Axiocam HSM camera (Zeiss) and operated at a 30 ms frame rate. Images were processed using Axiovision software (Zeiss). Images of fluid movement within the device are shown in Figures 4C-4E.

[0102] FIG. 4B is a photograph of sample 400b of Example 1 prior to cutting the exemplary fluidic device from the remainder of the sample. More specifically, in the photograph of sample 400b, various features are visible, including hydrophilic mask material 414 having the shape of a channel with a 90 degree bend 409. The thick dotted line 407 indicates the perimeter that will be cut to form the fluidic device from sample 400b. Once cut, the fluid sample can be wicked up into the fluidic device by contacting the fluid with either the first edge 411 or the third edge 415 at the location of the hydrophilic mask material 414. Whichever edge is used, the design of the hydrophilic mask material 414 allows gas and fluid to exit from the other edge. The gold material has a darker tone than the hydrophilic mask material 414, indicating a bonded portion 418 of sample 400b that surrounds the hydrophilic mask material 414.

[0103] FIG. 4C is a stereomicroscope image of a portion of the exemplary fluidic device 400c of Example 1 prior to contact with deionized water. It can be seen that the hydrophilic mask material 414 is surrounded by the bond portion 418, except for the first edge 411 and the third edge 415 of the fluidic device 400c. FIG. 4D is a stereomicroscope image of a portion of the fluidic device of Example 1 after 1.685 seconds of contact with water. In addition to the hydrophilic mask material 414 and the bond portion 418, a volume of water 495 is visible on the hydrophilic mask material 414, wicking up a distance along the open volume provided by the interstitial space between the hydrophilic mask material 414 and the second polymer layer (not visible), from the first edge 411 to the location of the large arrow 421d partway along the linear channel. FIG. 4E is a stereomicroscope image of a portion of the fluidic device of Example 1 after 3.370 seconds of contact with water. In fluidic device 400e, it can be seen that additional wicking time has caused water 495 to move further within the open volume, from the first edge 411, along the channel, past the 90 degree bend, and toward the third edge 415 at the location of large arrow 421e.

[0104] Example 2. The laminated sample 500a shown in Figure 5A was prepared using the general procedure described above. A fluidic device 500b (Figure 5B) having a perimeter (outside dimensions of 15 mm x 8 mm) defined by the superimposed dotted lines 507 in Figure 5A was cut from the laminated sample 500a using a razor blade. The hydrophilic mask material 514 was 2 mm wide and formed a straight channel extending from a first edge 511 to a second edge 513.

[0105] A droplet of deionized water was contacted with the hydrophilic material edge opening 511 (FIG. 5A) according to the method described in Example 1. After the hanging drop was contacted with the edge opening, the advancing water meniscus was monitored according to the method described in Example 1. Images of fluid movement within the device are shown in FIGS. 5B-5E.

[0106] FIG. 5A is a photograph of the sample of Example 2 prior to cutting the exemplary fluidic device from the rest of the sample. More specifically, in the photograph of sample 500a, various features are visible, including hydrophilic mask material 514 having the shape of a straight channel. The thick dotted line 507 indicates the perimeter that will be cut to form the fluidic device from sample 500a. Once cut, the fluid sample can be wicked up into the fluidic device by contacting the fluid with either the first edge 511 or the second edge 513 at the location of the hydrophilic mask material 514. Whichever edge is used, the design of the hydrophilic mask material 514 allows gas and fluid to vent out the other edge. A gold material that is a darker shade than the hydrophilic mask material 514 indicates the bonded portions 518 of sample 500a on either side of the hydrophilic mask material 514.

[0107] FIG. 5B is a stereomicroscope image of a portion of the fluidic device 500b of Example 2 after 0.062 seconds of contact with deionized water. It can be seen that the hydrophilic mask material 514 has the shape of a channel with binding portions 518 on either side of the hydrophilic mask material 514. A volume of water 595 is seen to begin to wick up into the first edge 511 of the fluidic device 500b at the beginning of the hydrophilic mask material 514. FIG. 5C is a stereomicroscope image of a portion of the fluidic device 500c of Example 2 after 3.577 seconds of contact with water. By this time, the water 595 has wicked up a distance from the first edge 511 to the location of the large arrow 521c partway along the linear channel toward the second edge 513 along the open volume provided by the interstitial space between the hydrophilic mask material 514 and the second polymer layer (not visible). FIG. 5D is a stereomicroscope image of a portion of the fluidic device of Example 2 after 4.555 seconds of contact with water. Fluid 595 has wicked up a further distance along the open volume at large arrow 521d, closer towards second edge 513. Figure 5E is a stereomicroscope image of a portion of fluidic device 500e of Example 2 after 7.051 seconds of contact with water. By this time, water 595 has wicked up all the way to second edge 513 at large arrow 521e.

[0108] Example 3. The laminated sample 600a shown in Figure 6A was prepared using the general procedure described above. A fluidic device 600b (Figure 6B) having a perimeter (external dimensions of 15 mm x 8 mm) defined by the superimposed dotted line 607 in Figure 6A was cut from the laminated sample 600a using a razor blade. The hydrophilic mask material 614 formed an 8 mm x 8 mm rectangular channel with edges aligned with the first, second, and third edges (611, 613, 615).

[0109] A droplet of deionized water was contacted with the hydrophilic material edge opening 615 (FIG. 6B) according to the method described in Example 1. After the hanging drop was contacted with the edge opening, the advancing water meniscus was monitored according to the method described in Example 1. Images of fluid movement within the device are shown in FIGS. 6B-6D.

[0110] FIG. 6A is a photograph of the sample of Example 3 prior to cutting the exemplary fluidic device from the remainder of the sample. More specifically, in the photograph of sample 600a, various features are visible, including hydrophilic masking material 614 having a rectangular shape. The thick dotted line 607 indicates the perimeter that will be cut to form the fluidic device from sample 600a. Once cut, a fluid sample can be wicked into the fluidic device by contacting the fluid with either the first edge 611, the second edge 613, or the third edge 615 at the location of the hydrophilic masking material 614. The hydrophilic masking material 614 has a continuous shape that extends completely along the first edge 611, along the opposing second edge 613, and along the third edge 615 located between the first edge 611 and the second edge 613. This configuration allows for ventilation of air and / or liquid at any point along each of the edges during use of the fluidic device. The gold material, which is a darker shade than the hydrophilic mask material 614 , indicates the bonded portions 618 of the sample 600 a adjacent the hydrophilic mask material 614 .

[0111] FIG. 6B is a stereomicroscope image of a portion of the fluidic device 600b of Example 3 after contact with deionized water for 1.841 seconds. It can be seen that the hydrophilic mask material 614 has a rectangular shape with a bond portion 618 on the left side of the hydrophilic mask material 614 and an interface 690 between the hydrophilic mask material 614 and the bond portion 618. A volume of water 695 is seen to begin wicking up into the third edge 615 of the fluidic device 600b along the open volume provided by the interstitial space between the hydrophilic mask material 614 and the second polymer layer (not visible). FIG. 6C is a stereomicroscope image of a portion of the fluidic device 600c of Example 3 after contact with water for 1.934 seconds. The water 695 has wicked up a further distance along the open volume towards the interface 690, reaching the second edge 613 opposite the first edge 611. FIG. 6D is a stereomicroscope image of a portion of the fluidic device 600e of Example 3 after contact with water for 2.402 seconds. By this time, some of the water 695 has wicked all the way up to the interface 690 between the hydrophilic mask material and the bonding portion 618 .

[0112] Example 4. The melt bondable film was prepared using compression molding. The upper and lower press platens of a hydraulic press were heated to 230°F (110°C). A sheet of polypropylene (C700-35N, Braskem, Philadelphia PA) was placed on the lower platen. Pellets of PEARLBOND 1160L polyurethane melt polymer (Lubrizol, Wickliffe, OH) were placed on the polypropylene sheet to form a densely packed monolayer approximately 10 cm in diameter. A sheet of MELINEX 454 polyester PET (Tekra, 5 mil thick) was placed on top of the pellets and a stainless steel sheet (0.8 mm thick) was placed on top of the PET sheet. The platens were closed to 10,000 pounds of pressure for 5 minutes, followed by cooling under pressure to 70°F (21.1°C). After cooling, the platens were separated and the bondable film was peeled from the polypropylene layer. A hydrophilic mask coating having silanol and siloxane groups was applied to the bondable film according to the procedure described in the section "General Procedure for Preparation of Fluidic Devices" using the patterned mask 600 depicted in FIG. 4A.

[0113] The lower platen of the press was heated to 50° C. and a piece of bondable film was placed on the heated lower platen for 30 seconds with the hydrophilic material treated surface of the film facing away from the lower platen surface. A 5 mil thick sheet of MELINEX 454 polyester PET film (Tekra) was placed on the bondable film. The press was closed and held using hand pressure to laminate the film. The resulting laminated sample was removed from the press and cooled to room temperature. The laminated sample was cut with a razor blade to provide the fluidic device 200 depicted in FIG. 2A. A 3 microliter droplet of human citrated blood was contacted with the hydrophilic edge opening 215 (FIG. 2A) of the fluidic device using a transfer pipette. After contacting the blood sample with the edge opening, the advancing meniscus of the blood was monitored according to the method described in Example 1. Images of fluid movement within the device are shown in FIGS. 2B-2C.

[0114] All of the above-mentioned patents and patent applications are expressly incorporated herein by reference. The above-mentioned embodiments are illustrative of the invention, and other configurations are possible. Accordingly, the invention should not be deemed limited to the embodiments described in detail above and illustrated in the accompanying drawings, but instead should be deemed limited only by the fair scope of the following claims together with their equivalents.

Claims

1. a) a first bondable polymer layer having a first major surface that is substantially planar; b) a second polymer layer having a first major surface that is substantially planar; c) a hydrophilic mask material disposed on a first portion of the first major surface of the first bondable polymer layer, the surface of the hydrophilic mask material exhibiting an advancing contact angle with water of less than 90 degrees, a fluid device comprising the hydrophilic mask material; wherein a second portion of the first major surface of the first bondable polymer layer is bonded to a first portion of the first major surface of the second polymer layer, the hydrophilic mask material and a second portion of the first major surface of the second polymer layer being in direct contact with each other at at least one point, an open volume being defined by a gap space located between the hydrophilic mask material and the second portion of the first major surface of the second polymer layer, the open volume including two or more openings, at least one of the two or more openings being located at an edge of the first bondable polymer layer, a fluid device.

2. The first portion of the first major surface of the first bondable polymer layer on which the hydrophilic mask material is disposed is a continuous region extending from a first edge of the first bondable polymer layer to each of an opposing second edge of the first bondable polymer layer and a third edge of the first bondable polymer layer located between the first edge and the second edge of the first bondable polymer layer, the fluid device according to Claim 1.

3. The first portion extends along the entire length of the third edge, the fluid device according to Claim 2.

4. The first portion of the first major surface of the first bondable polymer layer on which the hydrophilic mask material is disposed is a) from a first portion of the third edge of the first bondable polymer layer to i) at least one of the first edge or the second edge of the first bondable polymer layer, or ii) back to the third edge of the first bondable polymer layer at a position spaced from the first portion of the third edge, b) from a first portion of the second edge of the first bondable polymer layer, i) to at least one of the first edge or the third edge of the first bondable polymer layer, or ii) back to the second edge of the first bondable polymer layer at a position spaced from the first portion of the second edge, or c) from a first portion of the first edge of the first bondable polymer layer, i) to at least one of the second edge or the third edge of the first bondable polymer layer, or ii) back to the first edge of the first bondable polymer layer at a position spaced from the first portion of the first edge to define a pattern of fluid paths, the fluid device according to claim 2.

5. The fluid device according to claim 4, wherein the first portion of the first major surface of the first bondable polymer layer has a shape having a length that is at least 10 times greater than the width of the shape.

6. The fluid device according to claim 4, wherein the first portion of the first major surface of the first bondable polymer layer has a linear shape including a straight portion, a curved portion, or a combination thereof.

7. The fluid device according to claim 1, wherein the hydrophilic mask material comprises a plasma deposited silicon / oxygen material or diamond-like glass, nanostructure, surfactant, polyester, polyamide, polyurethane, poly(vinyl alcohol), poly(alkylene glycol), poly(alkylene oxide), poly(vinyl pyrrolidone), rubber elastomer, or a combination thereof.

8. The fluid device according to claim 1, wherein the first bondable polymer layer comprises low density polyethylene, ethylene vinyl acetate, ethylene acrylic acid, polyurethane, a copolymer of polyester and polyolefin, a copolymer of polyurethane and aromatic poly(meth)acrylate, a copolymer of polycaprolactone and polyurethane, or a combination thereof.

9. The fluid device according to claim 1, wherein the second polymer layer comprises polyolefin, polyester, polyamide, poly(vinyl chloride), polyether ester, polyimide, polyester amide, polyacrylate, polyvinyl acetate, ethylene acrylic acid adhesive, or a hydrolyzed derivative of polyvinyl acetate, or a combination thereof.

10. The first bondable polymer layer has a Vicat softening temperature (T ｇ ) of 100 degrees Celsius (°C) or less, the fluid device according to claim 9.

11. The fluidic device according to claim 1, wherein at least one of the first bindable polymer layer or the second polymer layer comprises a reagent configured to react with a sample and provide a response selected from electrochemistry, optics, fluorescence, chemiluminescence, or a combination thereof.

12. The fluidic device according to claim 11, wherein at least one of the first bindable polymer layer or the second polymer layer further comprises a detector.

13. The fluidic device according to claim 1, wherein the interstitial space comprises a volume of 500 nanoliters or less per square centimeter of the first portion of the first major surface of the first bindable polymer layer.

14. The fluidic device according to claim 1, further comprising a channel connecting the first portion of the first major surface of the first bindable polymer layer to at least one of the second major surface of the first bindable polymer layer or the second major surface of the second polymer layer.

15. At least one of the first portion of the first major surface of the first bondable polymer layer or the second portion of the first major surface of the second polymer layer has an average surface roughness (R ａ ) of 1 nanometer (nm) to 5 micrometers (μm), and the at least one contact point between the hydrophilic mask material and the second portion of the first major surface occurs at a position of the maximum height of the surface roughness. The fluid device according to claim 1.

16. The fluidic device according to claim 1, having a maximum gap of 5 μm between the first edge of the first bindable polymer layer and the directly adjacent first edge of the second polymer layer.

17. The fluidic device according to any one of claims 1 to 16, wherein the hydrophilic mask material has an average thickness of 1 nm to 1 μm.

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