Hydrophobic cartridge for digital microfluidics

Abstract

Methods and composites for making and / or forming hydrophobic cartridges for use with digital microfluidic (DMF) devices are disclosed. The hydrophobicity of the DMF cartridge can be improved by mixing an effective amount of one or more fluorinated surfactants with a polymer or polycarbonate resin used to form the cartridge. A method for preparing a molding compound for use in a DMF cartridge may include heating a composite of a polycarbonate and a fluorinated surfactant for a predetermined period of time.

Description

Priority claim

[0001] This patent application claims priority to U.S. Provisional Patent Application No. 63 / 350,618, entitled “HYDROPHOBIC CARTRIDGE FOR DIGITAL MICROFLUIDICS” and filed on June 9, 2022, which is incorporated herein by reference in its entirety. Incorporated by Reference

[0002] All publications and patent applications mentioned in this specification are herein incorporated by reference in their entirety to the same extent as if each individual publication or patent application was specifically and individually indicated to be incorporated by reference. field

[0003] The present disclosure relates to digital microfluidic devices and related fluid manipulation and extraction devices, and methods of making the same. background

[0004] Digital microfluidics (DMF) is a powerful technology that is simple and precisely manipulated for the microscale droplets of a fluid.DMF rapidly becomes popular in chemical, biological and medical applications because it allows direct control of multiple reagents (no pumps, valves or tubings are required), is easy to handle both solids and liquids (no channel clogging), and is compatible with even troublesome reagents (e.g., organic solvents, corrosive chemicals) because the hydrophobic surfaces (typically treated with one or more hydrophobic coatings) contacted with the fluid droplets are chemically inert. Conventional DMF equipment uses a relatively large electric field that is selectively applied to an electrode array to manipulate the droplet. The generation and control of these electric fields require a dedicated and complex circuit that can withstand relatively high voltages.

[0005] However, hydrophobic coatings need to be applied by additional processing steps.Therefore, there is a need to obtain hydrophobic surfaces with fewer processing steps. Summary of the Disclosure

[0006] Described herein are methods and components disclosed for preparing and / or forming a hydrophobic cartridge, such as, but not limited to, a hydrophobic cartridge for use with any digital microfluidics (DMF) device. The hydrophobicity of a DMF cartridge can be improved by mixing a fluorinated surfactant with a polymer or polycarbonate resin used to form the DMF cartridge.

[0007] For example, the present invention describes a microfluidic box comprising: a first plate having a first side and a second side; and a second plate; wherein the first plate and the second plate are fixed relative to and parallel to each other, with an air gap between the first plate and the second plate, and further wherein at least the first plate comprises an injection molding compound comprising: polycarbonate and an effective amount of a fluorinated surfactant for increasing the hydrophobicity of the first plate.

[0008] Typically, any of these boxes can be a digital microfluidics (DMF) box. For example, the box can be used with a DMF device and can include a first (e.g., top) plate having a first side and a second side; a ground electrode disposed on the first side of the top plate; a second (e.g., bottom) plate, wherein at least the top plate and the bottom plate contain an injection molding compound comprising polycarbonate and an effective amount of a fluorinated surfactant for increasing the hydrophobicity of the top plate and the bottom plate; and a frame configured to separate the top plate from the bottom plate and form an air gap between the top plate and the bottom plate, wherein the first side of the top plate is disposed toward the frame.

[0009] In any of the boxes disclosed herein, the effective amount of the fluorinated surfactant can be about 0.4% by weight of the polycarbonate. In any of the boxes, the fluorinated surfactant can be configured to bubble (bloom) on the surface of the top plate and the bottom plate. In addition, in any of the boxes disclosed herein, the fluorinated surfactant can be configured to increase the deionized water contact angle relative to the top plate and the bottom plate to greater than about 90 degrees.

[0010] In any of the boxes disclosed herein, the fluorinated surfactant is trifluoroethyl methacrylate (TFMA). In addition, the injection molding compound may also include a colorant in an amount of about 4% by weight of the polycarbonate. The colorant may be a colorant that is Clariant Mevopur NC7M820049.

[0011] In any of the boxes disclosed herein, the ground electrode may be disposed on the surface of the top plate. In addition, in any of the boxes, the ground electrode may be formed of an opaque material, conductive ink, silver nanoparticles, or a combination thereof.

[0012] In any of the kits disclosed herein, the polycarbonate can be a medical grade polycarbonate resin. In any of the kits disclosed herein, the fluorinated surfactant is Cytonix FluoroPel TFMA-6.

[0013] An exemplary method for preparing a hydrophobic injection molding compound for use in a cartridge device is disclosed. The exemplary method may include grinding a fluorinated surfactant into a powder, forming a compound by combining the fluorinated surfactant and more than one polycarbonate pellet together, actively mixing the compound for at least five minutes, and heating the compound to about 115 degrees Celsius for at least four hours after actively mixing.

[0014] In any of the methods described herein, the amount of the fluorinated surfactant can be about 0.4% by weight of more than one polycarbonate pellet. In addition, any of the methods can include adding a colorant in an amount of about 4% by weight of more than one polycarbonate pellet to the composite, wherein the active mixing further includes actively mixing the colorant with the more than one polycarbonate pellet. The colorant can be Clariant Mevopur NC7M820049. In any of the methods, the colorant can be added before heating the composite.

[0015] In any of the methods described herein, the fluorinated surfactant may be trifluoroethyl methacrylate (TFMA). In any of the methods described herein, the fluorinated surfactant may be Cytonix FluoroPel TFMA-6.

[0016] In any of the methods, more than one polycarbonate pellet can be a medical grade polycarbonate pellet. In addition, in any of the methods, the fluorinated surfactant can be a dry melt hydrophobic additive. In any of the methods described herein, actively mixing the composite can occur at ambient temperature.

[0017] Other exemplary methods may include receiving a composite of a fluorinated surfactant and a polycarbonate pellet, heating and controlling the temperature of the composite to a temperature of about 250 degrees Celsius, and injecting the composite into an injection mold. In any of the methods described herein, the amount of the fluorinated surfactant may be about 0.4% by weight of the polycarbonate pellet. In addition, in any of the methods, the fluorinated surfactant may be trifluoroethyl methacrylate (TFMA).

[0018] In any of the methods described herein, the composite can include a colorant in an amount of about 4% by weight of the polycarbonate pellets. Additionally, the colorant can be Clariant Mevopur NC7M820049.

[0019] Any of the methods described herein may also include aging the box for a period of not less than two days after injection prior to using the box. In any of the methods, the polycarbonate pellets are medical grade polycarbonate pellets. In addition, the fluorinated surfactant may be a dry melt hydrophobic additive. In any of the methods described herein, the composite may be heated to a temperature of about 115 degrees Celsius for a period of about four hours prior to being received.

[0020] All methods and apparatus described herein in any combination are contemplated herein and may be used to achieve the benefits as described herein. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] A better understanding of the features and advantages of the methods and apparatus described herein will be obtained by referring to the following detailed description, which sets forth illustrative embodiments, and the accompanying drawings, in which: Figure 1 is a flow chart depicting an exemplary method of preparing a composite for making a cartridge for use with any microfluidic device.

[0022] Figure 2 is a flow chart depicting an exemplary method for injection molding an article for use with a microfluidic device.

[0023] Figure 3 An exploded view of a simplified representation of a microfluidic cartridge is shown.

[0024] Figure 4 An exploded view of another exemplary microfluidic cartridge is shown.

[0025] Figure 5 Three different exemplary images showing the contact angle of deionized water using conventional polymers or polycarbonate resins are shown.

[0026] Figure 6 shows the use of a display similar to that of Figure 1 Three different exemplary images of deionized water contact angles of polymers or polycarbonate resins of the described formulations (eg, formulations including TFMA). Detailed Description

[0027] Methods and compositions for preparing and / or forming a hydrophobic cartridge for use with any microfluidic device are disclosed. The hydrophobicity of the microfluidic cartridge can be improved by mixing one or more fluorinated surfactants with a polymer or polycarbonate resin prior to heating the resulting composition for use in an injection molding process.

[0028] Figure 11 is a flow chart depicting an exemplary method 100 for preparing a composite for making a box for use with any microfluidic device, including but not limited to a digital microfluidic (DMF) device. Injection molding is described herein, but any other feasible method can be used to form the box. Conventional injection molding techniques can use a polymer as a primary material. The hydrophobicity of the primary material can be increased by adding a fluorinated surfactant. In addition, one or more colorants can also be added to the primary material. The colorant may not affect the hydrophobicity, but can allow decorative coloring of the box.

[0029] Method 100 can start with grinding the fluorinated surfactant in frame 110. In some instances, the fluorinated surfactant can be in the form of pellets. In some other instances, the fluorinated surfactant can have irregular (e.g., uneven) size and shape. Therefore, grinding can provide a more uniform size and shape of the fluorinated surfactant. This uniform size and shape can allow the surfactant to be more evenly distributed in the main material. In some instances, the fluorinated surfactant can be ground into a fine powder.

[0030] In some variations, the fluorinated surfactant can be trifluoroethyl methacrylate (TFMA). A non-limiting example of a TFMA can be FluroPel TFMA-6 from Cytonix LLC. Other TFMA surfactants are possible. In some examples, the TFMA can be a dry melt hydrophobic additive.

[0031] Next, in frame 120, the constituent components of the injection molding material are combined. The constituent components of the injection molding material may include a primary material, a fluorinated surfactant, and (optionally) a colorant. To ensure a consistent product with uniform hydrophobic properties, the amount of each component of the injection molding material may be determined relative to the weight of the primary material.

[0032] The primary material can be any polymer or polymer-like material suitable for injection molding. In some instances, the primary material can be a polycarbonate resin. A non-limiting example of a polycarbonate resin can be Makrolon 2458 resin. In some variations, the polycarbonate resin can be any feasible medical grade polycarbonate resin. The colorant can be any feasible colorant that is compatible with the primary material and the fluorinated surfactant. An exemplary colorant can be Clariant Mevopur NC7M820049.

[0033] The amount of fluorinated surfactant can be about 0.4% by weight relative to the weight of the primary material. In some examples, about 0.4% by weight relative to the weight of the primary material can be an effective amount of fluorinated surfactant for increasing the hydrophobicity of a box formed from such a composite. However, in some variations, the effective amount of fluorinated surfactant used can be greater or less than 0.4% by weight of the primary material.

[0034] The amount of colorant can be about 4% by weight relative to the weight of the main material. In some examples, about 4% by weight relative to the weight of the main material can be an effective amount of colorant for coloring a box formed from such a composite. In some variations, the effective amount of colorant used can be greater or less than 0.4% by weight of the main material.

[0035] Next, in block 130, the components are actively mixed. For example, the components mentioned in block 120 can be mixed for at least a minimum time period. An exemplary minimum time period can be five minutes, although any other feasible time period that evenly distributes the components of the composite can be used. In some variations, the mixing can be performed at ambient or room temperature. An exemplary ambient or room temperature can be 10 degrees Celsius, although other ambient temperatures can be used.

[0036] Next, in block 140, the components are heated. In some examples, the components may be heated at a controlled temperature for a minimum amount of time. For example, the minimum time period for heating the components may be about four hours, however other minimum time periods may be used. The controlled temperature may be about 115 degrees Celsius, however, in some other variations, other controlled temperatures may be used.

[0037] Figure 2 2 is a flow chart depicting an exemplary method 200 for injection molding an article for use with a device. The method 200 may be performed at block 210 by receiving an injection molding compound (e.g., Figure 1 For example, Figure 1 The described composition (eg, polymer, fluorinated surfactant in an amount of about 0.4% by weight of the polymer, and colorant in an amount of about 4% by weight of the polymer) can be received by a hopper of any suitable injection molding equipment.

[0038] Next, in block 220, the injection molding compound is heated. In some examples, the injection molding compound may be heated to about 250 degrees Celsius. In some variations, the injection molding compound may be heated to a temperature greater than 250 degrees Celsius, but only for a limited period of time. In some examples, heating the injection molding compound to a temperature of about 250 degrees Celsius may be sufficient to liquefy the molding compound, but not high enough to destroy or affect the hydrophobic properties of the TFMA contained in the compound.

[0039] Next, in block 230, the injection molding compound is injected into the mold. In some examples, the mold can be used for all or part of a cartridge. By molding all or part of a DMF cartridge with a compound containing TFMA, the corresponding cartridge can have increased hydrophobicity compared to a cartridge made without TFMA.

[0040] In some variations, the injection molded part may be aged for a predetermined period of time after being injected into the mold. In some instances, the predetermined period of time may be as few as two days after injection molding and in some cases as many as ten days. Waiting for the predetermined period of time to elapse may allow the TFMA to "bubble" on the outer surface of the injection molded part. The aging process may allow the surface of the injection molded part to develop maximum hydrophobicity.

[0041] One or more components of a cartridge for use with any viable microfluidic device may be as described with respect to Figure 2 Described as Figure 1 The described injection molding compound is injection molded. The resulting box can have one or more hydrophobic surfaces. For example, the hydrophobic surface can improve the performance of the associated box by reducing surface fouling.

[0042] Figure 3 An exploded view of a simplified representation of a cassette 300 configured as a DMF cassette is shown. Exemplary DMF cassettes and apparatus are described in commonly assigned U.S. Patent Application No. 16 / 259,984, filed on January 28, 2019, now U.S. Patent No. 11,311,882, the disclosure of which is incorporated herein by reference in its entirety.

[0043] The DMF box 300 may include an upper frame 310, a top plate 320, a tensioning frame 330, a bottom plate 340, and a base 350. Other boxes 300 may include, for example, Figure 3 In some variations, the components of DMF box 300 can be combined with those described in more or less parts. Figure 3 The method shown and described in the figure is arranged differently.

[0044] The top plate 320 can be coupled to the upper frame 310. In some variations, the top plate 320 can include a conductive material that can be used as an electrode (e.g., as a ground electrode). In some instances, the electrode can be formed of an opaque material, a conductive ink, and / or silver nanoparticles. The combination of the upper frame 310 and the top plate 320 can be coupled to the tensioning frame 330. The bottom plate 340 can also be coupled to the tensioning frame 330. In some instances, the bottom plate 340 can be thin and relatively flexible. In some variations, the tensioning frame 330 can keep the thin and flexible bottom plate 340 flat by providing a uniform outward (relative to the center of the bottom plate 340) tension to the bottom plate 340.

[0045] The tension frame 330 can be mounted (coupled) to the base 350. The base 350 can facilitate the temporary installation and / or attachment of the DMF box 300 to the DMF device (not shown). The tension frame 330 can provide or form an air gap 335 between the top plate 320 and the bottom plate 340. In addition, one or more openings can be provided in the top plate 320 and / or the bottom plate 340 to allow the user to introduce samples, reagents or the like into the air gap 335. Samples, reagents and other chemicals can be used to provide any feasible analysis or determination of samples.

[0046] One or more components of the cartridge 300 may be comprised of Figure 1 The composite material described is formed and as described with respect to Figure 2 Described injection molding is carried out.Therefore, the surface of the parts of DMF box 300 can be hydrophobic.Especially, top plate 320 and base plate 340 can be hydrophobic, and this can reduce any surface fouling related to the DMF activity in air gap 335.In addition, DMF box 300 can include one or more openings, to allow sample, reagent, liquid and the like to be introduced in air gap 335.Any one of these devices can include the air gap between the first plate and the second plate.The air gap can be configured to droplet is maintained between the plates, for example, contact two plates or contact at least one plate (for example, base plate).The air gap can be between about 0.1 mm and about 7 mm (for example, between about 0.2 mm and about 5 mm, between about 0.2 mm and about 4 mm, between about 0.3 mm and about 5 mm, between about 0.2 mm and about 3.5 mm, between about 0.2 mm and about 3 mm, etc.).

[0047] Figure 4An exploded view of another exemplary DMF box 400 is shown. The DMF box 400 can include a body 410, a top plate 420, a frame 430, and a bottom plate 440. The body 410 can include one or more microfluidic channels and / or chambers (not shown) for dispensing or receiving fluids into / out of an air gap (not shown) defined between the top plate 420 and the bottom plate 440. In some examples, more than one connector 415 can allow solvents, reagents, samples, and the like to be introduced into the air gap of the DMF box 400.

[0048] In some examples, one or more reservoirs 416 can be attached to the body 410. The reservoir 416 can be used to store reagents or other solutions that can be used during analysis and / or determination. In addition, one or more waste containers 417 can also be attached to the body 410. The waste container 417 can be used to receive and / or store waste liquid generated during analysis and / or determination. For example, waste reagents or washing byproducts can be stored in the waste container 417. The body 410 can also include a protective film 418.

[0049] The top plate 420, the frame 430, and the bottom plate 440 may form an air gap of the DMF box 400. In some examples, the top plate 420, the frame 430, and the bottom plate 440 may be formed by Figure 1 The composite material described is formed and as described with respect to Figure 2 As described above, injection molding is performed. Thus, the top plate 420, frame 430, and / or bottom plate 440 may be formed of a hydrophobic material. Note that for convenience, we refer to a "top" plate and a "bottom" plate herein, however, these may be more accurately referred to herein as a first plate and a second plate, and may be arranged in any orientation (top / bottom), etc.

[0050] In some variations, top plate 420 may include a conductive material that may function as an electrode (eg, as a ground electrode). In some variations, bottom plate 440 may be thin and flexible, and held in tension by at least frame 430.

[0051] Figure 5 Three different exemplary images showing the deionized water contact angle using conventional polymers or polycarbonate resins are shown. The deionized water contact angle can provide an indication of hydrophobicity. Generally, the larger the water contact angle, the more hydrophobic the polymer or polycarbonate resin is.

[0052] In image 510, the first water drop 511 has a left contact angle 512 of about 87.58 degrees, a right contact angle 513 of about 86.69 degrees, and an average contact angle of about 87.14 degrees. In image 520, the second water drop 521 has a left contact angle 522 of about 88.94 degrees, a right contact angle 523 of about 88.93 degrees, and an average contact angle of about 88.94 degrees. In image 530, the third water drop 531 has a left contact angle 532 of about 86.48 degrees, a right contact angle 533 of about 87.97 degrees, and an average contact angle of about 87.23 degrees. Therefore, it can be seen that the average water contact angle of a conventional polymer or polycarbonate resin can be about 87.77 degrees.

[0053] Figure 6 shows the use of a display similar to that of Figure 1 Three different exemplary images of deionized water contact angles of polymers or polycarbonate resins of the described formulations (eg, formulations including TFMA).

[0054] In image 610, a first water drop 611 has a left contact angle 612 of about 94.68 degrees, a right contact angle 613 of about 94.34 degrees, and an average contact angle of about 94.51 degrees. In image 620, a second water drop 621 has a left contact angle 622 of about 94.49 degrees, a right contact angle 623 of about 91.97 degrees, and an average contact angle of about 93.23 degrees. In image 630, a third water drop 631 may have a left contact angle 632 of 95.46 degrees, a right contact angle 633 of 94.29 degrees, and an average contact angle of 94.88 degrees.

[0055] Therefore, for deionized water in contact with a polymer or polycarbonate resin containing TFMA, the total average of the water contact angle can be about 94.20 degrees. This total average water contact angle is greater than the total average water contact angle of a conventional polymer or polycarbonate resin. Therefore, a polymer or polycarbonate resin with TFMA can have a relatively high hydrophobicity.

[0056] It should be appreciated that all combinations of the foregoing concepts and additional concepts discussed in greater detail below (provided such concepts are not mutually inconsistent) are considered to be part of the inventive subject matter disclosed herein and can be used to achieve the benefits described herein.

[0057] The process parameters and step sequences described and / or illustrated herein are given by way of example only and may be changed as desired. For example, although the steps illustrated and / or described herein may be illustrated or discussed in a particular order, the steps do not necessarily need to be performed in the order illustrated or discussed. The various exemplary methods described and / or illustrated herein may also omit one or more steps described or illustrated herein, or include additional steps in addition to those disclosed.

[0058] When a feature or element is referred to as "on another feature or element" in this article, it can be directly on another feature or element, or there can also be intermediate features and / or elements. In contrast, when a feature or element is referred to as "directly on another feature or element", there are no intermediate features or elements. It will also be understood that when a feature or element is referred to as "connected", "attached" or "coupled" to another feature or element, it can be directly connected, attached or coupled to other features or elements, or there can be intermediate features or elements. In contrast, when a feature or element is referred to as "directly connected", "directly attached" or "directly coupled" to another feature or element, there are no intermediate features or elements. Although described or shown with respect to one embodiment, the features and elements described or shown in this way can be applied to other embodiments. It will also be understood by those skilled in the art that the reference to a structure or feature that is set to be "adjacent" to another feature can have a portion that covers adjacent features or is located below adjacent features.

[0059] The terms used herein are only used for the purpose of describing specific embodiments and are not intended to limit the present invention. For example, unless the context clearly indicates otherwise, as used herein, the singular forms "a", "an" and "the" are also intended to include plural forms. It will be further understood that when used in this specification, the terms "comprises" and / or "comprising" specify the presence of stated features, steps, operations, elements and / or parts, but do not exclude the presence or addition of one or more other features, steps, operations, elements, parts and / or groups thereof. As used herein, the term "and / or" includes any combination and all combinations of one or more of the associated listed items, and can be abbreviated as " / ".

[0060] For ease of description, spatially relative terms such as "under", "below", "lower", "over", "upper" and similar terms may be used herein to describe the relationship of one element or feature to another (multiple) element or feature, as illustrated in the accompanying drawings. It will be understood that spatially relative terms are intended to cover different orientations of the device in use and operation in addition to the orientation depicted in the accompanying drawings. For example, if the device in the accompanying drawings is inverted, the elements described as "below" or "below" other elements or features will be oriented to be "above" other elements or features. Therefore, the exemplary term "below" can cover both the above and below orientations. The device can be oriented in other ways (rotated 90 degrees or at other orientations), and the spatially relative descriptors used herein are interpreted accordingly. Similarly, unless otherwise specifically indicated, the terms "upwardly", "downwardly", "vertical", "horizontal" and similar terms are used herein only for the purpose of explanation.

[0061] Although the terms "first" and "second" may be used herein to describe a plurality of features / elements (including steps), these features / elements should not be limited by these terms unless the context otherwise indicates. These terms may be used to distinguish one feature / element from another feature / element. Thus, without departing from the teachings of the present invention, the first feature / element discussed below may be referred to as the second feature / element, and similarly, the second feature / element discussed below may be referred to as the first feature / element.

[0062] Throughout this specification and the claims that follow, unless the context requires otherwise, the word "comprise" and variations such as "comprises" and "comprising" mean that various components can be used together in methods and articles (e.g., compositions and apparatus including devices and methods). For example, the term "comprising" will be understood to imply the inclusion of any stated elements or steps but not the exclusion of any other elements or steps.

[0063] Generally, any apparatus and method described herein should be understood to be inclusive, but all or a subset of components and / or steps may optionally be exclusive and may be expressed as "consisting of a variety of components, steps, sub-components or sub-steps" or optionally "consisting essentially of a variety of components, steps, sub-components or sub-steps."

[0064] As used herein in the specification and claims, including those used in the examples, and unless otherwise expressly stated, all numbers may be interpreted as prefixed with the words "about" or "approximately", even if the term does not appear clearly. When describing magnitude and / or position, the wording "about" or "approximately" may be used to indicate that the value and / or position described are within the reasonable expected range of the value and / or position. For example, a numerical value may have a value as + / -0.1% of a stated value (or range of values), + / -1% of a stated value (or range of values), + / -2% of a stated value (or range of values), + / -5% of a stated value (or range of values), + / -10% of a stated value (or range of values), etc. Unless otherwise indicated by the context, any numerical value given herein should also be understood to include about or approximately this value. For example, if the value "10" is disclosed, then "about 10" is also disclosed. Any numerical ranges listed herein are intended to include all subranges contained therein. It should also be understood that when a value is disclosed, "less than or equal to" the value, "greater than or equal to the value", and possible ranges between the values ​​are also disclosed, as appropriately understood by the skilled person. For example, if the value "X" is disclosed, "less than or equal to X" and "greater than or equal to X" (e.g., where X is a numerical value) are also disclosed. It should also be understood that throughout the application, data is provided in a variety of different formats, and that the data represents endpoints and starting points and ranges for any combination of data points. For example, if a specific data point "10" and a specific data point "15" are disclosed, it should be understood that greater than, greater than or equal to, less than, less than or equal to, and equal to 10 and 15, and between 10 and 15 are considered to be disclosed. It should also be understood that each unit between two specific units is also disclosed. For example, if 10 and 15 are disclosed, then 11, 12, 13, and 14 are also disclosed.

[0065] Although various illustrative embodiments are described above, any of a plurality of changes may be made to the various embodiments without departing from the scope of the invention as described by the claims. For example, in selectable embodiments, the order in which the various described method steps are performed may often be changed, and in other selectable embodiments, one or more method steps may be skipped together. The optional features of various equipment and system embodiments may be included in some embodiments and not included in other embodiments. Therefore, the foregoing description is provided primarily for exemplary purposes and should not be construed as limiting the scope of the invention as set forth in the claims.

[0066] Examples and descriptions included herein show by way of illustration rather than limitation, specific embodiments in which the subject matter can be put into practice. As mentioned, other embodiments can be utilized and derived therefrom so that structural and logical substitutions and changes can be made without departing from the scope of the present disclosure. Only for convenience, such embodiments of the subject matter of the present invention may be referred to individually or jointly by the term "invention" herein, and if in fact more than one invention or inventive concept is disclosed, it is not intended that the scope of the present application is actively limited to any single invention or inventive concept. Therefore, although specific embodiments have been described and described herein, any arrangement calculated for achieving the same purpose may replace the specific embodiments shown. The present disclosure is intended to cover any and all modifications or variations of a variety of embodiments. After reading the above description, the combination of the above embodiments and other embodiments not specifically described herein will be apparent to those skilled in the art.

Claims

1. A microfluidic box, comprising: a first plate having a first side and a second side; Second board; The first plate and the second plate are fixed opposite to each other and in parallel, with an air gap between the first plate and the second plate, Furthermore, wherein at least the first sheet comprises an injection molding compound comprising: polycarbonate and an effective amount of a fluorinated surfactant for increasing the hydrophobicity of the first sheet.

2. The cartridge of claim 1, wherein the effective amount of the fluorinated surfactant is about 0.4% by weight of the polycarbonate.

3. The cartridge of claim 1 or 2, wherein the fluorinated surfactant is configured to bubble within the air gap on the surface of the first side of the plate.

4. The cartridge of any one of claims 1-3, wherein the fluorinated surfactant is configured to increase a deionized water contact angle relative to the top plate and the bottom plate to greater than about 90 degrees.

5. The cartridge of any one of claims 1-4, wherein the fluorinated surfactant is trifluoroethyl methacrylate (TFMA).

6. The cartridge of any one of claims 1-5, wherein the injection molding compound further comprises a colorant in an amount of about 4% by weight of the polycarbonate.

7. A box according to claim 6, wherein the colorant is Clariant Mevopur NC7M820049.

8. The cartridge of any one of claims 1-7, wherein the fluorinated surfactant is configured to increase the hydrophobicity of the first plate.

9. The cartridge of any one of claims 1-8, wherein the polycarbonate is a medical grade polycarbonate resin.

10. The box of any one of claims 1-9, wherein the fluorinated surfactant is Cytonix FluoroPel TFMA-6.

11. A cartridge for use with a digital microfluidics (DMF) device, the cartridge comprising: a top plate having a first side and a second side; a ground electrode disposed on the first side of the top plate; A bottom plate, wherein at least the top plate and the bottom plate comprise an injection molding compound, the injection molding compound comprising: Polycarbonate; and an effective amount of a fluorinated surfactant for increasing the hydrophobicity of the top sheet and the bottom sheet; and A frame is configured to separate the top plate from the bottom plate and form an air gap between the top plate and the bottom plate, wherein the first side of the top plate is disposed toward the frame.

12. The cartridge of claim 11, wherein the effective amount of the fluorinated surfactant is about 0.4% by weight of the polycarbonate.

13. The cartridge of claim 11, wherein the fluorinated surfactant is configured to foam on surfaces of the top plate and the bottom plate.

14. The cartridge of claim 11, wherein the fluorinated surfactant is configured to increase a deionized water contact angle relative to the top plate and the bottom plate to greater than about 90 degrees.

15. The cartridge of claim 11, wherein the fluorinated surfactant is trifluoroethyl methacrylate (TFMA).

16. The cartridge of claim 11, wherein the injection molding compound further comprises a colorant in an amount of about 4% by weight of the polycarbonate.

17. A box according to claim 16, wherein the colorant is Clariant Mevopur NC7M820049.

18. The cartridge of claim 11, wherein the fluorinated surfactant is configured to increase the hydrophobicity of the top plate and the bottom plate.

19. The cartridge according to claim 11, wherein the ground electrode is provided on a surface of the top plate.

20. The cartridge of claim 11, wherein the ground electrode is formed of an opaque material, conductive ink, silver nanoparticles, or a combination thereof.

21. The cartridge of claim 11, wherein the polycarbonate is a medical grade polycarbonate resin.

22. The cartridge of claim 11, wherein the fluorinated surfactant is Cytonix FluoroPelTFMA-6.

23. A method for preparing a hydrophobic injection molding compound for use in a cartridge for a digital microfluidics (DMF) device, the method comprising: grinding the fluorinated surfactant into a powder; forming a composite by combining the fluorinated surfactant and more than one polycarbonate pellets; actively mixing the composite for at least five minutes; and After active mixing, the composite was heated to about 115 degrees Celsius for at least four hours.

24. The method of claim 23, wherein the amount of the fluorinated surfactant is about 0.4% by weight of the more than one polycarbonate pellets.

25. The method of claim 23, further comprising adding a colorant to the composite in an amount of about 4% by weight of the more than one polycarbonate pellets, wherein actively mixing further comprises actively mixing the colorant with the more than one polycarbonate pellets.

26. The method of claim 25, wherein the colorant is Clariant Mevopur NC7M820049.

27. The method of claim 25, wherein the colorant is added prior to heating the composite.

28. The method of claim 23, wherein the fluorinated surfactant is trifluoroethyl methacrylate (TFMA).

29. The method of claim 23, wherein the fluorinated surfactant is Cytonix FluoroPelTFMA-6.

30. The method of claim 23, wherein the more than one polycarbonate pellets are medical grade polycarbonate pellets.

31. The method of claim 23, wherein the fluorinated surfactant is a dry melt hydrophobic additive.

32. The method of claim 23, wherein the mixing occurs at ambient temperature.

33. A method of preparing a cartridge for use with a digital microfluidics (DMF) device, the method comprising: receiving a composite of a fluorinated surfactant and polycarbonate pellets; heating and controlling the temperature of the composite to a temperature of about 250 degrees Celsius; as well as The composite is injected into an injection mold.

34. The method of claim 33, wherein the amount of the fluorinated surfactant is about 0.4% by weight of the polycarbonate pellets.

35. The method of claim 33, wherein the fluorinated surfactant is trifluoroethyl methacrylate (TFMA).

36. The method of claim 33, wherein the fluorinated surfactant is Cytonix FluoroPelTFMA-6.

37. The method of claim 33, wherein the composite comprises a colorant in an amount of about 4% by weight of the polycarbonate pellets.

38. The method of claim 37, wherein the colorant is Clariant Mevopur NC7M820049.

39. The method of claim 33, further comprising aging the cartridge for a period of not less than two days after injection prior to using the cartridge.

40. The method of claim 33, wherein the polycarbonate pellets are medical grade polycarbonate pellets.

41. The method of claim 33, wherein the fluorinated surfactant is a dry melt hydrophobic additive.

42. The method of claim 33, wherein the composite is heated to a temperature of about 115 degrees Celsius for a period of about four hours prior to being received.

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