Patent Application
20230313276
Due to the ease by which rare, expensive, and/or brand-name products may be forged, the likelihood of consumers inadvertently purchasing counterfeit products is on the rise. To prevent fraud and the economic impact thereof in these industries, high-value commercial products, works of art, currency, wine and spirits, and the like often include indications of authenticity. These anti-counterfeiting technologies provide evidence for the consumer that the product is genuine, and are important for economic stability of the markets impacted by forgery and fraud.
To address the issues discussed herein, an authentication assay using embedded deoxyribonucleic acid (DNA) taggants is provided. According to one aspect, the authentication assay may include a substrate and a sample of an authenticity label collected from a product. The substrate may have a plurality of physically separated assay locations. Each assay location of the plurality of assay locations may include a reporter oligonucleotide bound to the substrate via an anchor region. Each reporter oligonucleotide bound to each assay location of the plurality of assay locations may include a first region, a second region, and a third region. The first region may include a single-stranded toehold sequence that is common among each of the reporter oligonucleotides bound to each assay location of the plurality of assay locations. The second region may include a universal sequence that is common among each of the reporter oligonucleotides bound to each assay location of the plurality of assay locations. The third region may include unique sequence that is different for each of the reporter oligonucleotides bound to each assay location of the plurality of assay locations. The second and third regions of each reporter oligonucleotide may be prehybridized with a complementary strand having a sequence that is complementary to the second and third regions. The sample may include at least one DNA taggant having a sequence complementary to the first and second regions of each of the reporter oligonucleotides, and complementary to the third region of at least one reporter oligonucleotide bound to an assay location of the plurality of assay locations. The at least one DNA taggant may include a fluorophore molecule configured to emit light upon excitation. Incubation of the substrate with the sample may result in binding of the at least one DNA taggant to the at least one reporter oligonucleotide, thereby initiating a toehold-mediated DNA strand displacement reaction that exchanges the complementary strand of the at least one reporter oligonucleotide for the at least one DNA taggant including the fluorophore molecule. Excitation of the fluorophore molecule attached to the DNA taggant may produce a pattern of emitted light at one or more assay locations.
According to another aspect, a method for manufacturing an authentication assay using DNA taggants is provided. The method may include preparing a substrate with a plurality of physically separated assay locations. The method may further include synthesizing a plurality of reporter oligonucleotides, each of which has a first region including a single-stranded toehold sequence that is common among each of the reporter oligonucleotides, a second region including a universal sequence that is common among each of the reporter oligonucleotides, and a third region including a unique sequence that is different for each of the reporter oligonucleotides. The method may further include prehybridizing the second and third regions of each reporter oligonucleotide of the plurality of reporter oligonucleotides with a complementary strand having a sequence that is complementary to the second and third regions of each reporter oligonucleotide. The method may further include binding, via an anchor region, each reporter oligonucleotide of the plurality of reporter oligonucleotides to one of the plurality of physically separated assay locations such that each assay location includes a reporter oligonucleotide with a unique third region. The method may further include synthesizing at least one DNA taggant to have a sequence complementary to the first and second regions of each of the reporter oligonucleotides, and complementary to the third region of at least one reporter oligonucleotide bound to an assay location of the plurality of assay locations, the at least one DNA taggant including a fluorophore molecule configured to emit light upon excitation. The method may further include adding the at least one DNA taggant to an authenticity label configured to verify an authenticity of a product.
Incubation of the substrate with the sample may result in binding of the at least one DNA taggant to the at least one reporter oligonucleotide, thereby initiating a toehold-mediated DNA strand displacement reaction that exchanges the complementary strand of the at least one reporter oligonucleotide for the at least one DNA taggant including the fluorophore molecule. Excitation of the fluorophore molecule attached to the DNA taggant may produce a pattern of emitted light at one or more assay locations.
According to another aspect, an authentication assay using embedded DNA taggants is provided. The authentication assay may include a substrate and a sample of an authenticity label collected from a product. The substrate may have a plurality of physically separated assay locations. Each assay location of the plurality of assay locations may include a reporter oligonucleotide bound to the substrate via an anchor region. Each reporter oligonucleotide bound to each assay location of the plurality of assay locations may include a first region and a second region. The first region of each reporter oligonucleotide may include a universal sequence that is common among each of the reporter oligonucleotides bound to each assay location of the plurality of assay locations. The second region of each reporter oligonucleotide includes a unique sequence that is different for each of the reporter oligonucleotides bound to each assay location of the plurality of assay locations. The first and second regions of each reporter oligonucleotide may be prehybridized with a complementary strand having a sequence that is complementary to the first and second regions of each reporter oligonucleotide. The complementary strand may include a toehold sequence and a fluorophore molecule. The sample may include at least one DNA taggant having a same sequence as the first and second regions of at least one reporter oligonucleotide bound to an assay location of the plurality of assay locations, and a toehold sequence complementary to the toehold sequence of the complementary strand. Incubation of the substrate with the sample may result in binding of the at least one DNA taggant to the complementary strand, thereby initiating a toehold-mediated DNA strand displacement reaction that displaces the complementary strand, including the fluorophore molecule, from the at least one reporter oligonucleotide. Exposure of the substrate to light configured to excite fluorophore molecules may produce a pattern of emitted light at one or more assay locations, the pattern including an absence of emitted light at one or more assay locations of the plurality of assay locations due to release of the complementary strand, including the fluorophore molecule.
This Summary is provided to introduce a selection of concepts in a simplified form that are further described below in the Detailed Description. This Summary is not intended to identify key features or essential features of the claimed subject matter, nor is it intended to be used to limit the scope of the claimed subject matter. Furthermore, the claimed subject matter is not limited to implementations that solve any or all disadvantages noted in any part of this disclosure.
Several significant challenges exist in distinguishing counterfeit goods from authentic goods. Anti-counterfeit technologies, such as holograms, optical strips, radio frequency identification (RFID), quick response (QR) codes, and near-field communication (NFC) add security to a product and provide evidence that the product is genuine. However, these technologies may be lost or damaged after application, difficult to attach to products, and easy to copy. Additionally, it may not be feasible to use such tagging mechanisms with products that are small, flexible, or numerous in quantity, or in scenarios in which the code should be invisible to the naked eye.
An assay using embedded molecular tags would provide an anti-counterfeit technology that is difficult to mimic. Molecular tagging is inexpensive, fast, reliable, simple to decode, and would thus improve the efficiency of conducting authentication analyses and negate the need for performing several individual assays. Further, in combination with the above features, the ability to detect results of the assay quickly and easily with a hand-held light and mobile computing device would enable a user to perform the assay from start to finish in virtually any location. An assay having these characteristics would offer the ability to confirm authenticity of a product quickly and reliably without the requirement for large equipment and laboratory space. However, heretofore challenges have existed for the development of such an assay.
As illustrated in
The reporter oligonucleotide 14 is bound to the substrate 10 via the anchor region 18. The substrate 10 may be a nitrocellulose membrane, as it is widely used for immobilizing nucleic acids. The anchor region 18 may be designed to be a poly-thymine ((poly)T) tail at the 3′ end of the reporter oligonucleotide 14 that binds to the nitrocellulose membrane. However, it will be appreciated that the (poly)T tail may be located at the 5′ end of the reporter oligonucleotide, and/or the reporter oligonucleotide 14 may form a stable interaction with the nitrocellulose membrane via a different mechanism, such as modifying an end of the reporter oligonucleotide 14 with biotin such that it can form a strong bond with streptavidin-coated nitrocellulose membrane, for example. Additionally or alternatively, the substrate may be an eggshell membrane (ESM), for example. It has been demonstrated that ESM treated with acetic acid or n-butyl acetate can be used to immobilize nucleic acids having terminal amine groups. Other substrates, such as nylon membranes, nanofibers, chitosan-modified membranes, for example, may be used to bind and retain nucleic acids in the multiplex assay described herein.
The authentication assay 100 further includes a sample 24 of an authenticity label 36 collected from a product 38, as described in detail below with reference to
During incubation, the DNA taggant 26 binds to the toehold region 21 of the reporter oligonucleotide 14 via the first region 21′ that is complementary to the toehold region 21, as illustrated in
The fluorophore molecule 28 is attached to the DNA taggant 26, and is thus configured to label the reporter oligonucleotide 14 when the toehold-mediated DNA strand displacement reaction results in binding of the second and third regions 22′, 23′ of the DNA taggant 26 to the first, second, and third regions region 21, 22, 23 of the reporter oligonucleotide 14. As shown in
Each assay location 12 of the plurality of assay locations may have a reporter oligonucleotide 14 with a unique sequence. An example reporter oligonucleotide 14 is depicted in the enlarged illustration of the assay location 12 in
As described above and shown in the figures, the plurality of assay locations 12 on the substrate 10 are physically separated from one another. In one implementation, the physical separation of the assay locations 12 is achieved via depositing a pattern of barriers on the substrate. Specifically, when the substrate 10 is configured as a nitrocellulose membrane, a wax-based printer may be used to deposit wax to form the pattern of barriers. When the wax is heated, it permeates the nitrocellulose membrane, thereby forming hydrophobic barriers to physically separate the assay locations 12 from one another, as depicted by the shaded portions of
The addition of the authenticity label 36 to a product 38 is illustrated in
In the example shown in
In the example shown in
As indicated above, the authenticity label 36 may be configured to encode binary data. For example, the DNA strands of the taggants that include the first, second, and third regions 21′, 22′, 23′ may be defined as DNAbits. In the assay 100 described herein, the fluorophore-labeled DNA taggants 26 may encode 1s of DNAbits, and the decoy DNA taggants 34 that lack the fluorophore molecule 28 may encode 0s of DNAbits. The binding of the DNA taggants 26 and decoy DNA taggants 34 to reporter oligonucleotides 14 bound to different assay locations 12 result conversion of the 1s and 0s encoded in the DNAbits to a pattern of fluorescence, thereby enabling the authenticity of a product, as well as additional data, to be determined in a single, multiplex assay that simplifies the reading process.
A system 102 for analyzing the authentication assay 100 may include a light emitting device, an optical reader 42, and a computing device 46. The light emitting device may be a handheld light, as described above with reference to
An example of the system 102 for analyzing the authentication assay 100 is shown in
A second embodiment of an authentication assay 200 using embedded DNA taggants will now be described.
As shown in
The authentication assay 200 further includes a sample 224 of the authenticity label 236 collected from the product 38. The sample 224 includes at least one DNA taggant 226, as illustrated in
During incubation, the DNA taggant 226 binds to the toehold sequence 221′ of the complementary strand 220 via the sequence 221 that is complementary to the toehold sequence 221′, as illustrated in
As with the authentication assay 100, the addition of the DNA taggants 226 and decoy DNA taggants 234 to the reporter oligonucleotides 214 at each assay location 212 create a fluorescent authenticity pattern on the substrate 10 upon excitation of the fluorophore molecules 28. However, as described below with reference to
The addition of the authenticity label 236 to a product 238 is illustrated in
In the example shown in
As indicated above, the authenticity label 236 may be configured to encode binary data. For example, the DNA strands of the taggants that include the toehold-binding, first, and second regions 221, 222, 223 may be defined as DNAbits. In the assay 200 described herein, the DNA taggants 226 may encode 1s of DNAbits, and the decoy DNA taggants 234, which prevent toehold-mediated strand displacement and removal of the fluorophore molecule 28 from the reporter oligonucleotide 214, may encode 0s of DNAbits. The binding of the DNA taggants 226 and lack of binding of the decoy DNA taggants 234 to reporter oligonucleotides 214 bound to different assay locations 212 result conversion of the 1s and 0s encoded in the DNAbits to a pattern of fluorescence, thereby enabling the authenticity of a product, as well as additional data, to be determined in a single, multiplex assay that simplifies the reading process.
As described above with reference to
A potential downfall of using DNA taggants to authenticate products is that DNA can be copied via PCR and/or sequenced by anyone with access to suitable equipment and reagents. This may lead to forgery of the labels and application of forged labels to counterfeit products. However, as discussed above, the combination of DNA taggants and decoy DNA taggants in the authenticity labels 36, 236 described herein make it difficult to mimic the DNA taggants. As such, attempts to forge the DNA taggants would result in the inability reproduce the fluorescent authenticity pattern on the substrate 10, thereby protecting the authenticity labels 36, 236 against counterfeiting and forgery. Additionally, each label may contain millions of copies of DNA taggants and decoy DNA taggants, thereby providing a high level of redundancy.
As the information encoded in the DNA taggants is encoded by both the sequences and the hybridization state, it is not possible to determine the information, and thus the fluorescent authenticity pattern, by sequencing alone. Additionally, the DNA taggants are designed to be difficult to sequence.
In
To further prevent fraudulent sequencing of the DNA taggants and reporter oligonucleotides described herein, the DNA strands may be chemically modified. For example, a phosphoramidite C3 spacer can be incorporated into the sequence of the DNA taggant and/or the reporter oligonucleotide, which introduces a long hydrophilic spacer arm to which fluorophores or other molecules may be attached. A C3 spacer can be added to one or both ends of the DNA taggant and/or the reporter oligonucleotide to modify the 5′ phosphate group and/or the 3′ hydroxyl group. Such modification blocks the ligation of DNA sequencing adapters to the DNA taggant and/or the reporter oligonucleotide, thereby preventing sequencing of the DNA taggant and/or the reporter oligonucleotide. Additional chemical modifications that alter the 3′ and/or 5′ ends of the DNA taggants and/or reporter oligonucleotides to prevent sequencing may include adding phosphorothioate (PS) bonds to the 5′ and/or 3′ ends, phosphorylating the 3′ ends, and/or linking an inverted dideoxythymidine (dT) to the 3′ and/or 5′ ends. Additionally, such chemical modifications may also be implemented to reduce degradation of the DNA taggants and the reporter oligonucleotides by exonucleases and other enzymes. It will be appreciated that the chemical modifications described herein are not intended to be limiting, and that other suitable chemical modifications may be employed to prevent sequencing and reproduction of the DNA taggants and/or reporter oligonucleotides to create fraudulent authenticity labels, as well as to prevent degradation of the DNA taggants and/or reporter oligonucleotides.
As an additional security measure for ensuring the fluorescent authenticity patterns described herein remain highly challenging to replicate, the sequences and patterns may be periodically changed. For example, the assay locations containing reporter oligonucleotides configured to undergo toehold-mediated DNA strand displacement upon incubation with a sample may be moved or rotated. Additionally or alternatively, the sequences of homology may be changed. In some implementations, the authenticity label may contain a plurality of DNA taggants, but the substrate is configured to detect only a subset of the DNA taggants.
Mimicking the fluorescent authenticity pattern via brute force is challenging, as the number of possible combinations of fluorescence is 2number of sequences. Additionally, at the server level, the processor of the authentication server may be configured to recognize multiple attempts using different fluorescent authenticity patterns to verify a product from a same user and implement a computational warning after a threshold number of attempts to authenticate a product using different fluorescent authentication patterns.
Continuing from step 302 to step 304, the method 300 may include synthesizing a plurality of reporter oligonucleotides. Each of the reporter oligonucleotides may have a first region including a single-stranded toehold region, a second region including a universal sequence that is common among each of the reporter oligonucleotides, and a third region including a unique sequence that is different for each of the reporter oligonucleotides.
Proceeding from step 304 to step 306, the method 300 may include prehybridizing the second and third regions of each reporter oligonucleotide of the plurality of reporter oligonucleotides with a complementary strand. The complementary strand may have a sequence that is complementary to the second and third regions of each reporter oligonucleotide.
Advancing from step 306 to step 308, the method 300 may include binding each reporter oligonucleotide to one of the plurality of physically separated assay locations. The binding may be facilitated by an anchor region included in each reporter oligonucleotide. As such, each assay location may include a reporter oligonucleotide with a unique sequence in the third region
Continuing from step 308 to step 310, the method 300 may include synthesizing at least one DNA taggant. The DNA taggant may have a sequence complementary to the first and second regions of each of the reporter oligonucleotides, and complementary to the third region of at least one reporter oligonucleotide bound to an assay location of the plurality of assay locations. The DNA taggant may further include a fluorophore molecule that is configured to emit light upon excitation.
Proceeding from step 310 to step 312, the method 300 may include adding the DNA taggant to an authenticity label that is configured to verify an authenticity of a product. As described above, when the substrate is incubated with a sample of the authenticity label, the DNA taggant binds to the toehold region of the reporter oligonucleotide. This binding initiates a toehold-mediated DNA strand displacement reaction thereby exchanging the complementary strand of the at least one reporter oligonucleotide with the at least one DNA taggant. As the DNA taggant includes the fluorophore molecule, a user can verify an authenticity of the product via a pattern of emitted light at one or more assay locations of the plurality of assay locations upon excitation of the fluorophore molecule attached to the DNA taggant.
The embodiments described above may be used to verify the authenticity of a product quickly and accurately. The authentication assays are configured to display patterns of fluorescence specific to respective products without the need for a quenching molecule, thereby providing a cost-effective mechanism for using fluorescence technology to label products. The cost of manufacturing the authenticity assay is further reduced in embodiments in which the fluorophore molecule is configured to label the reporter oligonucleotide anchored to the substrate, as fewer fluorophore molecules are needed compared to embodiments in which the DNA taggants are fluorescently labeled. Additionally, the authenticity label may contain a combination of DNA taggants and decoy DNA taggants, making it difficult to mimic the DNA taggants and reproduce the fluorescent authenticity pattern on the substrate, and thereby protecting the authenticity labels against counterfeiting and forgery. Furthermore, the described authenticity labels can be embedded in a variety of solid, powdered, and liquid materials, and each label includes millions of copies of DNA taggants, thereby providing a high level of redundancy. In addition to verifying the authenticity of products, binary data may be encoded in the DNA taggants, which enables the authenticity labels to be used for tracking and accountability in supply chains. The DNA taggants may be designed to indicate a source of the product, materials used in the manufacture of the product, and any treatments or special processes a product or commodity has undergone. With these technical aspects, the authentication assay embodiments described herein provide numerous advantages over existing authenticity label technology.
The following paragraphs provide additional description of aspects of the present disclosure. According to one aspect an authentication assay using embedded deoxyribonucleic acid (DNA) taggants is provided, comprising a substrate having a plurality of physically separated assay locations, each assay location of the plurality of assay locations including a reporter oligonucleotide bound to the substrate via an anchor region, and a sample of an authenticity label collected from a product. In this aspect, each reporter oligonucleotide bound to each assay location of the plurality of assay locations includes a first region, a second region, and a third region, the first region of each reporter oligonucleotide includes a single-stranded toehold sequence that is common among each of the reporter oligonucleotides bound to each assay location of the plurality of assay locations, the second region of each reporter oligonucleotide includes a universal sequence that is common among each of the reporter oligonucleotides bound to each assay location of the plurality of assay locations, the third region of each reporter oligonucleotide includes a unique sequence that is different for each of the reporter oligonucleotides bound to each assay location of the plurality of assay locations, the second and third regions of each reporter oligonucleotide are prehybridized with a complementary strand having a sequence that is complementary to the second and third regions of each reporter oligonucleotide, the sample includes at least one DNA taggant having a sequence complementary to the first and second regions of each of the reporter oligonucleotides, and complementary to the third region of at least one reporter oligonucleotide bound to an assay location of the plurality of assay locations, the at least one DNA taggant including a fluorophore molecule configured to emit light upon excitation, incubation of the substrate with the sample results in binding of the at least one DNA taggant to the at least one reporter oligonucleotide, thereby initiating a toehold-mediated DNA strand displacement reaction that exchanges the complementary strand of the at least one reporter oligonucleotide for the at least one DNA taggant including the fluorophore molecule, and excitation of the fluorophore molecule attached to the DNA taggant causes the fluorophore molecule to emit light, thereby resulting in a pattern of emitted light at one or more assay locations.
In an example configuration of the authentication assay according to this aspect, the at least one DNA taggant is one of a plurality of DNA taggants included in the sample, and each DNA taggant of the plurality of DNA taggants included in the sample has a third region with a unique sequence complementary to a third region of a reporter oligonucleotide bound to one of the assay locations of the plurality of assay locations.
In an example configuration of the authentication assay according to this aspect, the sample additionally includes at least one decoy DNA taggant having a third region with a unique sequence complementary to a reporter oligonucleotide bound to one of the assay locations of the plurality of assay locations, the at least one decoy DNA taggant lacking a fluorophore molecule.
A system for analyzing the authentication assay of this aspect is also provided. In an example configuration, the system comprises a light emitting device configured to emit light at a wavelength that causes excitation of the fluorophore molecule attached to the DNA taggant; an optical reader configured to capture the pattern of emitted light; and a computing device configured to receive data encoding the pattern of emitted light from the optical reader, perform a verification action on the pattern of emitted light, and output a verification result.
In an example configuration of the authentication assay according to this aspect, the light emitting device is a handheld light, the optical reader is a camera-equipped mobile computing device, and the computing device is a server configured to receive the data encoding the pattern of emitted light over a computer network from the mobile computing device.
In an example configuration of the authentication assay according to this aspect, the authenticity label is included in a coating applied to a surface of the product.
In an example configuration of the authentication assay according to this aspect, when the product is a liquid product, the authenticity label is added directly to the product.
According to another aspect, a method for manufacturing an authentication assay using embedded deoxyribonucleic acid (DNA) taggants is provided, the method comprising: preparing a substrate to have a plurality of physically separated assay locations; synthesizing a plurality of reporter oligonucleotides, each of which has a first region including a single-stranded toehold sequence that is common among each of the reporter oligonucleotides, a second region including a universal sequence that is common among each of the reporter oligonucleotides, and a third region including a unique sequence that is different for each of the reporter oligonucleotides; prehybridizing the second and third regions of each reporter oligonucleotide of the plurality of reporter oligonucleotides with a complementary strand having a sequence that is complementary to the second and third regions of each reporter oligonucleotide; binding, via an anchor region, each reporter oligonucleotide of the plurality of reporter oligonucleotides to one of the plurality of physically separated assay locations such that each assay location includes a reporter oligonucleotide with a unique sequence in the third region; synthesizing at least one DNA taggant to have a sequence complementary to the first and second regions of each of the reporter oligonucleotides, and complementary to the third region of at least one reporter oligonucleotide bound to an assay location of the plurality of assay locations, the at least one DNA taggant including a fluorophore molecule configured to emit light upon excitation; and adding the at least one DNA taggant to an authenticity label configured to verify an authenticity of a product, wherein incubation of the substrate with a sample of the authenticity label results in binding of the at least one DNA taggant to the at least one reporter oligonucleotide, thereby initiating a toehold-mediated DNA strand displacement reaction that exchanges the complementary strand of the at least one reporter oligonucleotide for the at least one DNA taggant including the fluorophore molecule, and excitation of the fluorophore molecule attached to the DNA taggant causes the fluorophore molecule to emit light, thereby resulting in a pattern of emitted light at one or more assay locations.
In an example configuration of the method according to this aspect, the at least one DNA taggant is one of a plurality of DNA taggants included in the sample, and the method further comprises synthesizing each DNA taggant of the plurality of DNA taggants included in the sample to have a third region with a unique sequence complementary to a reporter oligonucleotide bound to one of the assay locations of the plurality of assay locations.
In an example configuration of the method according to this aspect, the method further comprises synthesizing at least one decoy DNA taggant having a third region with a unique sequence complementary to a reporter oligonucleotide bound to one of the assay locations of the plurality of assay locations, the at least one decoy DNA taggant lacking a fluorophore molecule; and including the at least one decoy DNA taggant in the authenticity label.
In an example configuration of the method according to this aspect, the method further comprises exciting the fluorophore molecule attached to the DNA taggant with a light emitting device, and capturing the pattern of emitted light with an optical reader.
In an example configuration of the method according to this aspect, the method further comprises receiving an authentication result output from a computing device configured to receive data encoding the pattern of emitted light from the optical reader and perform an authentication action on the pattern of emitted light.
In an example configuration of the method according to this aspect, the method further comprises including the authenticity label in a coating applied to a surface of the product.
In an example configuration of the method according to this aspect, the method further comprises, when the product is a liquid product, adding the authenticity label to the product.
According to another aspect, an authentication assay using embedded deoxyribonucleic acid (DNA) taggants is provided, the assay comprising: a substrate having a plurality of physically separated assay locations, each assay location of the plurality of assay locations including a reporter oligonucleotide bound to the substrate via an anchor region; and a sample of an authenticity label collected from a product, wherein each reporter oligonucleotide bound to each assay location of the plurality of assay locations includes a first region and a second region, the first region of each reporter oligonucleotide includes a universal sequence that is common among each of the reporter oligonucleotides bound to each assay location of the plurality of assay locations, the second region of each reporter oligonucleotide includes a unique sequence that is different for each of the reporter oligonucleotides bound to each assay location of the plurality of assay locations, the first and second regions of each reporter oligonucleotide are prehybridized with a complementary strand having a sequence that is complementary to the first and second regions of each reporter oligonucleotide, the complementary strand including a toehold sequence and a fluorophore molecule, the sample includes at least one DNA taggant having a same sequence as the first and second regions of at least one reporter oligonucleotide bound to an assay location of the plurality of assay locations, and a toehold sequence complementary to the toehold sequence of the complementary strand, incubation of the substrate with the sample results in binding of the at least one DNA taggant to the complementary strand, thereby initiating a toehold-mediated DNA strand displacement reaction that displaces the complementary strand, including the fluorophore molecule, from the at least one reporter oligonucleotide, and exposure of the substrate to light configured to excite fluorophore molecules produces a pattern of emitted light at one or more assay locations, the pattern including an absence of emitted light at one or more assay locations of the plurality of assay locations due to release of the complementary strand, including the fluorophore molecule.
In an example configuration of the authentication assay according to this aspect, the at least one DNA taggant is one of a plurality of DNA taggants included in the sample, and each DNA taggant of the plurality of DNA taggants included in the sample has a second region with a same unique sequence as a second region of a reporter oligonucleotide bound to one of the assay locations of the plurality of assay locations.
In an example configuration of the authentication assay according to this aspect, the sample additionally includes at least one decoy DNA taggant having a same universal sequence as the first region of at least one reporter oligonucleotide, a different sequence than a unique sequence of a second region of the at least one reporter oligonucleotide, and a toehold sequence complementary to the toehold sequence of the complementary strand, and the DNA taggant is prehybridized with a blocking strand having a same sequence as the toehold sequence and first region of the complementary strand, thereby blocking the toehold-mediated DNA strand displacement reaction that displaces the complementary strand, including the fluorophore molecule, from the at least one reporter oligonucleotide.
A system is provided for analyzing the authentication assay of this aspect. In one example configuration, the system comprises a light emitting device configured to emit light at a wavelength that causes excitation of a fluorophore molecule attached to the complementary strand; an optical reader configured to capture the pattern of emitted light, including the absence of emitted light at one or more assay locations; and a computing device configured to receive data encoding the pattern of emitted light from the optical reader, perform a verification action on the pattern of emitted light, and output a verification result, wherein the light emitting device is a handheld light, the optical reader is a camera-equipped mobile computing device, and the computing device is a server configured to receive the data encoding the pattern of emitted light over a computer network from the mobile computing device.
In an example configuration of the authentication assay according to this aspect, the authenticity label is included in a coating applied to a surface of the product.
In an example configuration of the authentication assay according to this aspect, when the product is a liquid product, the authenticity label is added directly to the product.
It will be understood that the configurations and/or approaches described herein are exemplary in nature, and that these specific embodiments or examples are not to be considered in a limiting sense, because numerous variations are possible. The specific routines or methods described herein may represent one or more of any number of processing strategies. As such, various acts illustrated and/or described may be performed in the sequence illustrated and/or described, in other sequences, in parallel, or omitted. Likewise, the order of the above-described processes may be changed.
The subject matter of the present disclosure includes all novel and non-obvious combinations and sub-combinations of the various processes, systems and configurations, and other features, functions, acts, and/or properties disclosed herein, as well as any and all equivalents thereof.
