WO2023003534A1

WO2023003534A1 - Nucleic acid testing devices including an actuating reagent chamber

Info

Publication number: WO2023003534A1
Application number: PCT/US2021/042191
Authority: WO
Inventors: Viktor Shkolnikov; Michael W. Cumbie
Original assignee: Hewlett-Packard Development Company, L.P.
Priority date: 2021-07-19
Filing date: 2021-07-19
Publication date: 2023-01-26

Abstract

An example of degrading amplified nucleic acids includes expelling a nucleic acid degradation reagent from a reagent chamber in a nucleic acid testing device by actuating the reagent chamber, and expelling an amplified nucleic acid from an amplification chamber of the nucleic acid testing device. The method further includes mixing the amplified nucleic acid and the nucleic acid degradation reagent in a channel of the nucleic acid testing device, and collecting the mixed amplified nucleic acid and nucleic acid degradation reagent in a waste chamber of the nucleic acid testing device.

Description

NUCLEIC ACID TESTING DEVICES INCLUDING AN ACTUATING REAGENT

CHAMBER

Background

[0001] Nucleic acid amplification is a valuable molecular tool in research and in application oriented fields, such as clinical medicine development, infectious diseases diagnosis, gene cloning and industrial quality control. One method of nucleic acid amplification is Polymerase chain reaction (PCR), though other nucleic acid amplification methods exist. Several alternatives to PCR have been developed, including loop mediated isothermal amplification (LAMP), nucleic acid sequence based amplification (NASBA), self-sustained sequence replication (3SR), rolling circle amplification (RCA), strand displacement amplification (SDA), and ligase chain reaction (LCR). Each nucleic acid amplification method amplifies a target nucleic acid sequence to produce amplified products of nucleic acid

Brief Description of the Drawings

[0002] FIG. 1 illustrates a block diagram of an example method for degrading amplified nucleic acids, in accordance with the present disclosure.

[0003] FIG. 2 illustrates a block diagram of an example nucleic acid testing device including two actuating reagent chambers, in accordance with the present disclosure. [0004] FIG. 3 illustrates a block diagram of an example nucleic acid testing device including two actuating reagent chambers and a secondary heater, in accordance with the present disclosure.

[0005] FIG. 4 illustrates a block diagram of an example nucleic acid testing device including two actuating reagent chambers and two secondary heaters, in accordance with the present disclosure.

[0006] FIG. 5 illustrates a block diagram of an example nucleic acid testing device including two actuating reagent chambers, two secondary heaters, and a plurality of amplification chambers, in accordance with the present disclosure. [0007] FIG. 6 illustrates a block diagram of an example system for nucleic acid degradation, in accordance with the present disclosure.

Detailed Description

[0008] In the following detailed description, reference is made to the accompanying drawings which form a part hereof, and in which is shown by way of illustration specific examples in which the disclosure may be practiced. It is to be understood that other examples may be utilized and structural or logical changes may be made without departing from the scope of the present disclosure. The following detailed description, therefore, is not to be taken in a limiting sense, and the scope of the present disclosure is defined by the appended claims. It is to be understood that features of the various examples described herein may be combined, in part or whole, with each other, unless specifically noted otherwise.

[0009] Nucleic acid testing devices allow for the detection of a particular nucleic acid sequence and thus allow for the detection and identification of a particular species or subspecies of organism (often a virus or bacterium) that acts as a pathogen in certain contexts. Similarly, nucleic acid amplification techniques allow for the detection of minute amounts of nucleic acids such as deoxyribonucleic acid (DNA) and ribonucleic acid (RNA) in a sample by multiplying the nucleic acid of interest in a specimen thousands if not millions of times in order to analyze it later using various methods. [0010] Sometimes, false positive results may be obtained from a nucleic acid testing device because carryover contamination from one sample is amplified in another sample, resulting in amplification and detection of the amplified contaminant. Carryover contamination may occur from aerosol or other means of physically transferring amplified product generated from earlier amplification reactions into a different, later, amplification reaction. Carryover contamination may also result from traces of nucleic acid which originate with the amplification reagents. Following nucleic acid amplification, the concentration of the target nucleic acid may be 9 orders of magnitude higher than in the sample. Thus if the nucleic acid testing device leaks post amplification, the chance of contamination of the testing facility is high, which introduces cost and delays in testing.

[0011] Nucleic acid testing devices including an actuating reagent chamber, in accordance with the present disclosure, reduce the likelihood of subsequent false positive tests by degrading the amplified nucleic acid product after the completion of testing. An example of degrading amplified nucleic acids, in accordance with the present disclosure, includes expelling a nucleic acid degradation reagent from a reagent chamber in a nucleic acid testing device by actuating the reagent chamber, and expelling an amplified nucleic acid from an amplification chamber of the nucleic acid testing device. The method further includes mixing the amplified nucleic acid and the nucleic acid degradation reagent in a channel of the nucleic acid testing device, and collecting the mixed amplified nucleic acid and nucleic acid degradation reagent in a waste chamber of the nucleic acid testing device.

[0012] An example apparatus in accordance with the present disclosure includes a plurality of reagent chambers, wherein each reagent chamber stores a volume of a non-specific nucleic acid degradation reagent. The apparatus further includes an amplification chamber fluidically coupled to the plurality of reagent chambers via a fluid channel. The apparatus includes a mixing channel in fluid communication with the plurality of reagent chambers and the amplification chamber, and a waste chamber in fluid communication with the mixing channel. [0013] An example system in accordance with the present disclosure includes a nucleic acid testing device, including a plurality of reagent chambers, an amplification chamber in fluid communication with the plurality of reagent chambers, a mixing channel in fluid communication with the plurality of reagent chambers and the amplification chamber, and a waste chamber in fluid communication with the mixing channel. The system further includes a receiving chamber, including a surface to receive the nucleic acid testing device, and actuation circuitry to actuate the plurality of reagent chambers.

[0014]Turning now to the figures, FIG. 1 illustrates a block diagram of an example method 100 for degrading amplified nucleic acids, in accordance with the present disclosure. At 101, the method 100 includes expelling a nucleic acid degradation reagent from a reagent chamber in a nucleic acid testing device by actuating the reagent chamber. As used herein, a nucleic acid degradation reagent refers to or includes any solution that degrades a nucleic acid sequence. A non-limiting example of a nucleic acid degradation reagent includes a non-specific nuclease. Non-specific nucleases refer to a group of enzymes that degrade both single- and double-stranded DNA and RNA without sequence specificity. A nuclease is a phosphodiesterase that cleaves the phosphodiester bonds of nucleic acids. Both small molecule and macromolecule nucleases may be used. Non-limiting examples of small molecule nucleases include: 1,10 Phenanthroline-Copper; porphyrins such as 6'-

[(aminomethyl)pyridyl]porphyrin, ferrous- Ethylenediaminetetraacetic acid (EDTA), and uranyl acetate; metal-chelating tripeptides such as glycyl-glycyl-L- histidine, and glycyl-L-histidyl-L-lysine, and other small molecule nucleases. Non-limiting examples of macromolecule nucleases include: His-Me finger (bba- Me) nucleases; HUH (one-metal-ion catalysis) nucleases; DnaQ; E. coli Exol and ExoX; Three Prime Repair Exonuclease 1 (TREX1) and Three prime repair exonuclease 2 (TREX2); and WRN exonuclease.

[0015] As used herein, a nucleic acid testing device refers to or includes an apparatus that amplifies and/or detects a particular nucleic acid sequence. A reagent chamber refers to or includes an enclosure of a nucleic acid testing device that stores a volume of a nucleic acid degradation reagent. The volume of nucleic acid degradation reagent may be expelled from the reagent chamber responsive to actuation of the reagent chamber. As used herein, actuating a nuclease chamber refers to or includes puncturing and/or opening the reagent chamber to release the nucleic acid degradation reagent stored therein. As described more thoroughly herein, the reagent chamber may be in a variety of forms, and therefore the method to actuate the reagent chamber may differ based on the type of reagent chamber used.

[0016] In order to perform amplification of a nucleic acid sequence, the temperature of the solution in the amplification chamber may be heated and cooled in cycles. For instance, according to some amplification methods, the temperature of the solution in the amplification chamber is raised to approximately 95° Celsius (°C), cooled to approximately 55 °C, and held at approximately 75 °C. In additional examples, the method of amplification may include cycling the solution between two temperatures; a high temperature ranging between approximately 90-95°C, and a low temperature ranging between approximately 65-70°C. To amplify a segment of deoxyribonucleic acid (DNA) to detectable levels, this thermal cycle may be performed 20-40 times. The amplified nucleic acid may be detected using various methods, such as by visual detection using fluorescence resonance, and by visual inspection for color change, among other non-limiting examples.

[0017] At 103, the method 100 includes expelling an amplified nucleic acid from an amplification chamber of the nucleic acid testing device. As used herein, an amplification chamber refers to or includes an enclosure of the nucleic acid testing device within which nucleic acid amplification is performed and/or an enclosure of the nucleic acid testing device within which an amplified nucleic acid is detected. The amplified nucleic acid may be expelled from the amplification chamber by a variety of methods. As discussed further herein, the amplified nucleic acid may be expelled from the amplification chamber by actuating a reagent chamber of the nucleic acid testing device. For instance, the nucleic acid testing device may include a valve separating the reagent chamber and the amplification chamber that can be actuated to connect the two chambers. In such examples, the nucleic acid testing device may include a mechanism to drive the nucleic acid degradation reagent into the amplification chamber.

[0018] The nucleic acid testing device may include a plurality of reagent chambers and/or a plurality of amplification chambers. In some examples, the reagent chamber is a first reagent chamber, wherein the nucleic acid testing device includes a second reagent chamber, and expelling the amplified nucleic acid from the amplification chamber of the nucleic acid testing device includes actuating the second reagent chamber. For instance, as discussed with regards to FIG. 2, one of the reagent chambers may be fluidically coupled to the amplification chamber, and expelling the amplified nucleic acid at 103, may include actuating the reagent chamber fluidically coupled to the amplification chamber to release the contents of the amplification chamber by fluid flow. In such examples, the method may include actuating the first reagent chamber before actuating the second reagent chamber.

[0019] To prevent false positives due to leakage of amplified nucleic acid from the nucleic acid testing device, nucleic acid degradation reagent may be expelled into the amplification chamber post amplification. In some examples, the reagent chamber is a blister pack, and actuating the reagent chamber includes applying an actuation force to the blister pack. As used herein, a blister pack refers to or includes a cavity or pocket made from a formable web, such as a thermoformed plastic, and including a piercing backing which when broken, releases the contents of the cavity or pocket. In various examples of the present disclosure, a blister pack may be fluidically coupled to the amplification chamber such that in response to piercing the backing of the blister pack, the nucleic acid degradation reagent may be expelled into the amplification chamber. The nucleic acid testing device and/or a receiving chamber to receive the nucleic acid testing device may include a piercing device such as a pin to pierce the blister pack responsive to an actuation force. Similarly, the nucleic acid testing device and/or the receiving chamber may include a compression device to apply the actuation force on the blister pack, thereby forcing the piercing backing onto the piercing device and puncturing the piercing backing. Additionally and/or alternatively, the piercing device may move positions (e.g., up, down, and/or from one side to another) responsive to actuation in order to puncture the piercing backing.

[0020] In some examples, the reagent chamber is a heat shrink capsule, and actuating the reagent chamber includes applying heat to the heat shrink capsule. As used herein, a heat shrink capsule refers to or includes a cavity or pocket made from a shrinkable material. The heat shrink capsule may comprise a material that shrinks when exposed to heat. In response to the heat shrink capsule shrinking, the volume inside the heat shrink capsule (i.e., the nucleic acid degradation reagent) is expelled from the reagent chamber. Non-limiting examples of materials that may comprise the heat shrink capsule includes Polytetrafluoroethylene (PTFE), viton, polyvinylidene fluoride (PVDF), fluorinated ethylene propylene (FEP), elastomers, silicone rubber, and polyolefin, among others. In some examples, heat shrink materials may include shape memory alloy that returns to its previous contracted state. To actuate the heat shrink capsule, the heat shrink capsule may be heated to a temperature at or above the crystalline melting point of the material comprising the heat shrink capsule. The amount to which the heat shrink capsule shrinks responsive to application of heat also depends on the material comprising the heat shrink capsule. In response to the heat shrink capsule shrinking, the nucleic acid degradation reagent may be expelled from the heat shrink capsule.

[0021] At 105, the method 100 includes mixing the amplified nucleic acid and the nucleic acid degradation reagent in a channel of the nucleic acid testing device. Once the amplified nucleic acid will not be used for further testing, the amplified nucleic acid may be degraded via the nucleic acid degradation reagent. As an example, after nucleic acid amplification and/or testing, a blister pack containing the nucleic acid degradation reagent may be actuated. A first blister pack may expel the nucleic acid degradation reagent into the upstream opening of the amplification chamber, driving the fluid in the amplification chamber to a downstream opening of the amplification chamber. A second blister pack may also expel nucleic acid degradation reagent into a fluidic channel fluidically coupled to the amplification chamber. As discussed with regards to FIG. 2, the fluid from the amplification chamber contacts with the nucleic acid degradation reagent from the second blister pack, and flows through a mixing channel. While flowing through the mixing channel, the nucleic acid degradation reagent and the amplified nucleic acid are mixed.

[0022] As used herein, a mixing channel refers to or includes a fluidic channel that includes a mixer. The mixer may be a passive mixer and/or an active mixer. Upon mixing the amplified nucleic acid with the nucleic acid degradation reagent, the product nucleic acid is degraded to monomers and therefore cannot be subsequently amplified and cause false positives, even if the contents are exposed to the outside.

[0023] As used herein, a passive mixer refers to or includes a mixer that does not utilize an energy input other than the pressure head used to drive the fluid flow through the nucleic acid testing device. Non-limiting examples of a passive mixer include a staggered herringbone mixer (SHM), barrier-embedded mixers (BEM), and a three-dimensional serpentine channel mixing device, among others. As used herein, an active mixer refers to or includes a mixer that utilizes an energy input to mix a solution inside. Non-limiting examples of an active mixer includes magnetic beads, artificial cilia which are activated to generate (transverse) flow and mixing, and resistors, among others.

[0024] At 107 the method 100 includes collecting the mixed amplified nucleic acid and nucleic acid degradation reagent in a waste chamber of the nucleic acid testing device. As used herein, a waste chamber refers to or includes an enclosure to collect and store the product from the nucleic acid amplification and mixing with the nucleic acid degradation reagent. In some examples, the downstream part of the waste chamber may have a gas permeable membrane, allowing the gas from the waste chamber to escape as the chamber fills with liquid. In some examples, the waste chamber includes a surface functionalized with nucleases, such that the waste chamber may degrade any nucleic acid that may be in liquid droplets inadvertently passing into the waste chamber.

[0025] In various examples, the method includes expelling the nucleic acid degradation reagent from the reagent chamber after a nucleic acid is amplified in the amplification chamber. As such, once nucleic acid amplification is complete (and/or testing of the amplified nucleic acid is complete), and the amplified product will no longer be used, the nucleic acid degradation reagent may degrade the amplified product into monomers and that cannot be subsequently amplified and cause false positives, even if the contents of the waste chamber are exposed to the outside.

[0026] FIG. 2 illustrates a block diagram of an example nucleic acid testing device 202 including two actuating reagent chambers, in accordance with the present disclosure. In various examples, the nucleic acid testing device includes a plurality of reagent chambers, wherein each reagent chamber stores a volume of a non-specific nucleic acid degradation reagent. For instance, the nucleic acid testing device 202 may include a plurality of reagent chambers 209-1 , 209- 2. As discussed with regards to FIG. 1, reagent chamber 209-1 and reagent chamber 209-2 may store a volume of a non-specific nucleic acid degradation reagent.

[0027] The nucleic acid testing device also includes an amplification chamber fluidically coupled to the plurality of reagent chambers via a fluid channel. For instance, the nucleic acid testing device 202 includes an amplification chamber 211 fluidically coupled to the plurality of reagent chambers 209-1, 209-2 via fluidic channels 213-1 and 213-2. In various examples, the amplification chamber 211 may be disposed in proximity of heater 223. For instance, the heater 223 may be disposed beneath or above the amplification chamber 211 so as to heat the amplification chamber 211 by conduction. The heater 223 may heat the solution in the amplification chamber 211 according to a nucleic acid amplification method, as described herein.

[0028] The nucleic acid testing device also includes a mixing channel in fluid communication with the plurality of reagent chambers and the amplification chamber. For instance, the nucleic acid testing device 202 includes a mixing channel 215 in fluid communication with the plurality of reagent chambers 209-1 , 209-2 and the amplification chamber 211.

[0029] The nucleic acid testing device also includes a waste chamber in fluid communication with the mixing channel. For instance, the nucleic acid testing device 202 includes a waste chamber 217 in fluid communication with the mixing channel 215. In some examples, the downstream part of the waste chamber may have a gas permeable membrane 216, allowing the gas from the waste chamber to escape as the chamber fills with liquid.

[0030] Upon completing an amplification reaction in the amplification chamber 211 and measuring the result of the reaction, the reagent chambers 209-1 , 209- 2 may be actuated. As discussed with regards to FIG. 1, the manner in which the reagent chambers 209-1 , 209-2 are actuated depends on the form of the reagent chambers. In some examples, the plurality of reagent chambers 209-1, 209-2 are blister packs. In such examples, the piercing backing of each blister pack may be pierced to actuate the reagent chambers 209-1, 209-2. In some examples, the plurality of reagent chambers 209-1, 209-2 are heat shrink capsules. In such examples, the capsules may be heated to a temperature at or above the crystalline melting point of the material comprising the heat shrink capsule to actuate the reagent chambers 209-1 , 209-2.

[0031] In various examples, a first reagent chamber 209-1 is actuated to expel nucleic acid degradation reagent into fluidic channel 213-1 and into an upstream opening 219 of the amplification chamber 211, driving the fluid in the amplification chamber to a downstream opening 221 of the amplification chamber 211. The second reagent chamber 209-2 is also actuated to expel nucleic acid degradation reagent into fluidic channel 213-2. For instance, the first reagent chamber 209-1 and the second reagent chamber 209-2 may be actuated by a piercing device such as a pin to pierce the blister pack responsive to an actuation force. Similarly, the first reagent chamber 209-1 and the second reagent chamber 209-2 may be actuated by a compression device that applies an actuation force, thereby piercing the first reagent chamber 209-1 and the second reagent chamber 209-2. As described with regards to FIG. 6, the actuator may be coupled to actuation circuitry, and the actuator may apply an actuation force in response to an electrical impulse. In some examples, the first reagent chamber 209-1 and the second reagent chamber 209-2 may be actuated by application of heat. For instance, as described with regards to FIG. 3, circuitry may heat the first reagent chamber 209-1 and the second reagent chamber 209-2, which results in wax plugs melting and the first reagent chamber 209-1 and the second reagent chamber 209-2 shrinking to expel the contents therefrom. The designation of “first” and “second” are used throughout to denote different respective objects of a same type, but the designations do not connote an order. For instance, a first reagent chamber and a second reagent chamber may be of the same type, though the first reagent chamber does not have any particular order with respect to the second reagent chamber. As an example, the first reagent chamber 209-1 may be actuated before the second reagent chamber 209-2, and/or the second reagent chamber 209-2 may be actuated before the first reagent chamber 209-1.

[0032] FIG. 3 illustrates a block diagram of an example nucleic acid testing device 302 including two actuating reagent chambers and a secondary heater, in accordance with the present disclosure. The nucleic acid testing device 302 may be similar to the nucleic acid testing device 202 illustrated in FIG. 2, and similar components are numbered accordingly. For instance, reagent chambers 309-1 and 309-2 may be the same as or similar to reagent chambers 209-1, 209-2, amplification chamber 311 may be the same as or similar to amplification chamber 211 , heater 323 may be the same as or similar to heater 223, channels 313-1 and 313-2 may be the same as or similar to channels 213-1 and 213-2, mixing channel 315 may be the same as or similar to mixing channel 215, waste chamber 317 may be the same as or similar to waste chamber 217, upstream opening 319 may be the same as or similar to upstream opening 219, and downstream opening 321 may be the same as or similar to downstream opening 221.

[0033] In some examples, the amplification chamber is disposed proximal to a first heater, and the plurality of reagent chambers are disposed proximal to a second heater. For instance, referring to FIG. 3, the amplification chamber 311 may be disposed proximal to the first heater 323, and the reagent chambers 309-1 and 309-2 may be disposed proximal to a second heater 325. The second heater 325 may be embedded in a circuit board of the apparatus 302, for example along with the first heater 323, although examples are not so limited. In some examples, the second heater 325 is disposed external to the apparatus 302. [0034] In some examples, the plurality of reagent chambers are heat shrink capsules, and each heat shrink capsule includes a wax plug disposed between the reagent chamber and the fluid channel. For instance, referring to FIG. 3, heat shrink capsule 309-1 may include a wax plug 327-1 and heat shrink capsule 309-2 may include a wax plug 327-2. The wax plugs 327-1 and 327-2 may have a melting point at or below the crystalline melting point of the heat shrink capsules 309-1 and 309-2. That is, in some examples, the heat shrink capsules and wax plug have similar melting temperatures.

[0035] Upon completing the amplification reaction in the amplification chamber 311 and measuring the result of the reaction, the second heater 325 may be activated to force the heat shrink capsules 309-1 and 309-2 to reach the crystalline melting point and the wax plug to reach the melting point. In some examples, the heat flux from the second heater 325 may be temperature feedback controlled, such as by circuitry on apparatus 302 and/or on a receiving chamber to receive the apparatus 302 (not illustrated in FIG. 3). Upon reaching the melting points, the wax plugs 327-1 and 327-2 melt and the heat shrink capsules 309-1 and 309-2 contract. The contraction of the heat shrink capsules 309-1 and 309-2 pushes nucleic acid degradation reagent to expel therefrom. The flow of nucleic acid degradation reagent from the heat shrink capsule 309-1 into the upstream opening 319 of the amplification chamber 311, driving the fluid there to the downstream opening 321. The nucleic acid degradation reagent from the second heat shrink capsule 309-2 meets with nucleic acid degradation reagent from the first heat shrink capsule 309-1 , and gets mixed with the amplified nucleic acid in a mixing channel 315. As discussed herein, the mixed nucleic acid degradation reagent and amplified nucleic acid then travels to the waste chamber 317. Upon mixing with the nucleic acid degradation reagent the amplified nucleic acid is degraded to monomers and therefore cannot be subsequently amplified and cause false positives, even if the contents of the waste chamber 317 are exposed to the outside.

[0036] In some examples, the heat shrink capsules 309-1 and 309-2 may be actuated by an external heat source, including infrared and convective (heat gun) heat sources. In some examples, the reagent chambers 309-1 and 309-2 may be capsules that are under compression, similar to an expanded balloon, and the wax plugs 327-1 and 327-2 may hold the liquid in the capsule until activated by the heater. In such examples, the capsule comprising the respective reagent chamber 309-1 and 309-2 does not shrink, but the nucleic acid degradation reagent may nonetheless expel from the respective reagent chamber 309-1 and 309-2 responsive to melting of the wax plugs 327-1 and 327-2.

[0037] In some examples, the nucleic acid degradation reagent may be pumped into the amplification chamber 311 by a positive pressure on an upstream end 329 of the waste chamber 317 or negative pressure on a downstream end 331 of the waste chamber 317.

[0038] FIG. 4 illustrates a block diagram of an example nucleic acid testing device 402 including two actuating reagent chambers and two secondary heaters, in accordance with the present disclosure. The nucleic acid testing device 402 may be similar to the nucleic acid testing device 202 illustrated in FIG. 2 and/or the testing device 302 illustrated in FIG. 3, and similar components are numbered accordingly. For instance, reagent chambers 409-1 and 409-2 may be the same as or similar to reagent chambers 209-1, 209-2, amplification chamber 411 may be the same as or similar to amplification chamber 211 , heater 423 may be the same as or similar to heater 423, channels 413-1 and 413-2 may be the same as or similar to channels 213-1 and 213-2, wax plugs 427-1 and 427-2 may be the same as or similar to wax plugs 327-1 and 327-2 illustrated in FIG. 3, mixing channel 415 may be the same as or similar to mixing channel 215, waste chamber 417 may be the same as or similar to waste chamber 217, upstream opening 419 may be the same as or similar to upstream opening 219, and downstream opening 421 may be the same as or similar to downstream opening 221. Moreover, upstream end 429 of the waste chamber 417 and downstream end 431 of the waste chamber 417 may be the same as or similar to upstream end 329 of the waste chamber 317 and downstream end 331 of the waste chamber 317, illustrated in FIG. 3.

[0039] As illustrated in FIG. 4, different respective heaters may independently heat the respective reagent chambers 409-1, 409-2. In such examples, a controller (not illustrated in FIG. 4) may independently actuate reagent chambers 409-1 , 409-2. For instance, heater 433-2 may heat reagent chamber 409-2 to actuate reagent chamber 409-2 first, and heater 433-1 may heat reagent chamber 409-1 to actuate reagent chamber 409-1 second. Examples are not so limited, and reagent chamber 409-2 may be actuated at the same time as or after reagent chamber 409-1. Improved mixing of the amplified nucleic acid and the nucleic acid degradation reagent may be achieved by actuating reagent chambers 409-1, 409-2 independently. For instance, by actuating reagent chamber 409-2 first, and actuating reagent chamber 409-1 second, it may be ensured that the amplified nucleic acid is mixed with the nucleic acid degradation reagent in the mixing channel 415, as opposed to a portion of the amplified nucleic acid mixing within the mixing channel 415 without the nucleic acid degradation reagent.

[0040] FIG. 5 illustrates a block diagram of an example nucleic acid testing device 402 including two actuating reagent chambers, two secondary heaters, and a plurality of amplification chambers, in accordance with the present disclosure. The nucleic acid testing device 502 may be similar to the nucleic acid testing device 202 illustrated in FIG. 2, and similar components are numbered accordingly. For instance, reagent chambers 509-1 and 509-2 may be the same as or similar to reagent chambers 209-1 , 209-2, amplification chambers 511-1, 511-2, ...511-N (where N is any integer greater than 2) may each be the same as or similar to amplification chamber 211, heaters 523-1, 523-2, ...523-N may each be the same as or similar to heater 223, channels 513-1 and 513-2 may be the same as or similar to channels 213-1 and 213-2, mixing channel 515 may be the same as or similar to mixing channel 215, and waste chamber 517 may be the same as or similar to waste chamber 217. Moreover, wax plugs 527-1 and 527-2 may be the same as or similar to wax plugs 327-1 and 327-2 illustrated in FIG. 3, and heaters 533-1 and 533-2 may be the same as or similar to heaters 433-1 and 433-2 illustrated in FIG. 4 illustrated in FIG. 4

[0041] In some examples, as illustrated in FIG. 5, a reagent chamber may be in fluid communication with a plurality of amplification chambers. For instance, reagent chambers 509-1 may be in fluid communication with amplification chambers 511-1, 511-2, ...511-N, and coupled with each respective amplification chambers by fluidic channels 537-1, 537-2,... 537-N (respectively). Similarly, each respective amplification chamber 511-1 , 511-2,...511-N may be heated by different respective heaters 523-1, 523-2, ...523-N.

[0042] FIG. 6 illustrates a block diagram of an example system for nucleic acid degradation, in accordance with the present disclosure. As illustrated in FIG. 6, the example system 650 includes a nucleic acid testing device 602. The nucleic acid testing device 602 may be similar to the nucleic acid testing device 202 illustrated in FIG. 2, and similar components are numbered accordingly. For instance, reagent chambers 609-1 and 609-2 may be the same as or similar to reagent chambers 209-1 , 209-2, amplification chamber 611 may be the same as or similar to amplification chamber 211 , heater 623 may be the same as or similar to heater 223, channels 613-1 and 613-2 may be the same as or similar to channels 213-1 and 213-2, mixing channel 615 may be the same as or similar to mixing channel 215, waste chamber 617 may be the same as or similar to waste chamber 217, upstream opening 619 may be the same as or similar to upstream opening 219, and downstream opening 621 may be the same as or similar to downstream opening 221. In some examples, the downstream part of the waste chamber 617 may have a gas permeable membrane 616, allowing the gas from the waste chamber to escape as the chamber fills with liquid. As such, the nucleic acid testing device 602 includes a plurality of reagent chambers, an amplification chamber in fluid communication with the plurality of reagent chambers, a mixing channel in fluid communication with the plurality of reagent chambers and the amplification chamber, and a waste chamber in fluid communication with the mixing channel.

[0043] As illustrated in FIG. 6, the system 650 also includes a receiving chamber 654, including a surface to receive the nucleic acid testing device, and actuation circuitry to actuate the plurality of reagent chambers. For instance, the receiving chamber 654 may include a surface to receive the nucleic acid testing device 602, and actuation circuitry 653 to actuate the plurality of reagent chambers 609-1, 609-2. [0044] In some examples, the receiving chamber includes an actuator coupled to the actuation circuitry, the actuator including an apparatus to apply an actuation force to a reagent chamber of the plurality of reagent chambers in response to an electrical impulse. For instance, the receiving chamber 654 may include an actuator coupled to the actuation circuitry 653. As discussed with regards to FIG. 2, the actuator may be an apparatus to apply an actuation force to a blister pack in response to an electrical impulse, thereby actuating the blister pack.

[0045] In some examples, the receiving chamber includes an actuator coupled to the actuation circuitry, the actuator including a heater to heat a reagent chamber of the plurality of reagent chambers in response to an electrical impulse from actuation circuitry 653. For instance, the receiving chamber 654 may include an actuator coupled to the actuation circuitry, the actuator including a heater (e.g., heater 325 illustrated in FIG. 3 and/or heaters 433-1 and 433-2 illustrated in FIG. 4) to heat a reagent chamber of the plurality of reagent chambers in response to an electrical impulse from the actuation circuitry 653. [0046] In some examples, the system further includes a controller coupled to the actuation circuitry, the controller including a non-transitory machine readable medium storing instructions that, when executed, cause the controller to actuate the plurality of reagent chambers after a nucleic acid is amplified in the amplification chamber. For instance, the system 650 may include a controller 651 coupled to the actuation circuitry 653, the controller including a non- transitory machine readable medium storing instructions that, when executed, cause the controller to actuate the plurality of reagent chambers after a nucleic acid is amplified in the amplification chamber. The controller 651 may be a central processing unit (CPU), a semiconductor-based microprocessor, and/or other hardware device suitable to control operations of the system 650. The controller 651 may include and/or be communicatively coupled to a computer- readable storage medium. The computer-readable storage medium may be an electronic, magnetic, optical, or other physical storage device that contains or stores executable instructions. Thus, computer-readable storage medium may be, for example, Random Access Memory (RAM), an Electrically Erasable Programmable Read-Only Memory (EEPROM), a storage device, an optical disc, etc. In some examples, the computer-readable storage medium may be a non-transitory storage medium, where the term ‘non-transitory’ does not encompass transitory propagating signals. The computer-readable storage medium may be encoded with a series of executable instructions that allow the controller 651 to operate the system 650. For instance, the computer-readable storage medium may include instructions that when executed, cause the controller 651 to regulate temperature cycles of the heater 623 in proximity to the amplification chamber 611. As a further example, the computer-readable storage medium may include instructions that when executed, cause the controller 651 to regulate a temperature of a heater or heaters disposed proximal to reagent chambers 609-1 and 609-2. In some examples, the computer-readable storage medium may include instructions that when executed, cause the controller 651 to actuate an apparatus to apply an actuation force to reagent chambers 609-1 and 609-2. Similarly, the computer- readable storage medium may include instructions that when executed, cause the controller 651 to mix a solution in the mixing channel 615 using an active mixing mechanism. As yet a further example, the computer-readable storage medium may include instructions that when executed, cause the controller 651 to perform a testing method on the amplified nucleic acid in the amplification chamber 611.

[0047] Although specific examples have been illustrated and described herein, a variety of alternate and/or equivalent implementations may be substituted for the specific examples shown and described without departing from the scope of the present disclosure. This application is intended to cover any adaptations or variations of the specific examples discussed herein. Therefore, it is intended that this disclosure be limited only by the claims and the equivalents thereof.

Claims

1. A method, comprising: expelling a nucleic acid degradation reagent from a reagent chamber in a nucleic acid testing device by actuating the reagent chamber; expelling an amplified nucleic acid from an amplification chamber of the nucleic acid testing device; mixing the amplified nucleic acid and the nucleic acid degradation reagent in a channel of the nucleic acid testing device; and collecting the mixed amplified nucleic acid and nucleic acid degradation reagent in a waste chamber of the nucleic acid testing device.

2. The method of claim 1 , including expelling the nucleic acid degradation reagent from the reagent chamber after a nucleic acid is amplified in the amplification chamber.

3. The method of claim 1 , wherein the reagent chamber is a first reagent chamber, wherein the nucleic acid testing device includes a second reagent chamber, and expelling the amplified nucleic acid from the amplification chamber of the nucleic acid testing device includes actuating the second reagent chamber.

4. The method of claim 3, further including actuating the first reagent chamber before actuating the second reagent chamber.

5. The method of claim 1 , wherein the reagent chamber is a blister pack, and actuating the reagent chamber includes applying an actuation force to the blister pack.

6. The method of claim 1 , wherein the reagent chamber is a heat shrink capsule, and actuating the reagent chamber includes applying heat to the heat shrink capsule.

7. An apparatus, comprising: a plurality of reagent chambers, wherein each reagent chamber stores a volume of a non-specific nucleic acid degradation reagent; an amplification chamber fluidically coupled to the plurality of reagent chambers via a fluid channel; a mixing channel in fluid communication with the plurality of reagent chambers and the amplification chamber; and a waste chamber in fluid communication with the mixing channel.

8. The apparatus of claim 7, wherein the plurality of reagent chambers are blister packs.

9. The apparatus of claim 7, wherein: the amplification chamber is disposed proximal to a first heater; and the plurality of reagent chambers are disposed proximal to a second heater.

10. The apparatus of claim 7, wherein the plurality of reagent chambers are heat shrink capsules, and each heat shrink capsule includes a wax plug disposed between the reagent chamber and the fluid channel.

11. The apparatus of claim 10, wherein the heat shrink capsules and wax plug have similar melting temperatures.

12. A system, comprising: a nucleic acid testing device, including: a plurality of reagent chambers; an amplification chamber in fluid communication with the plurality of reagent chambers; a mixing channel in fluid communication with the plurality of reagent chambers and the amplification chamber; and a waste chamber in fluid communication with the mixing channel; a receiving chamber, including: a surface to receive the nucleic acid testing device; and actuation circuitry to actuate the plurality of reagent chambers.

13. The system of claim 12, wherein the receiving chamber includes an actuator coupled to the actuation circuitry, the actuator including an apparatus to apply an actuation force to a reagent chamber of the plurality of reagent chambers in response to an electrical impulse.

14. The system of claim 12, wherein the receiving chamber includes an actuator coupled to the actuation circuitry, the actuator including a heater to heat a reagent chamber of the plurality of reagent chambers in response to an electrical impulse.

15. The system of claim 12, further including a controller coupled to the actuation circuitry, the controller including a non-transitory machine readable medium storing instructions that, when executed, cause the controller to actuate the plurality of reagent chambers after a nucleic acid is amplified in the amplification chamber.