DETAILED ACTION
Notice of Pre-AIA or AIA Status
The present application, filed on or after March 16, 2013, is being examined under the first inventor to file provisions of the AIA .
In the event the determination of the status of the application as subject to AIA 35 U.S.C. 102 and 103 (or as subject to pre-AIA 35 U.S.C. 102 and 103) is incorrect, any correction of the statutory basis (i.e., changing from AIA to pre-AIA ) for the rejection will not be considered a new ground of rejection if the prior art relied upon, and the rationale supporting the rejection, would be the same under either status.
Status of the Claims
Claims 1-17 are pending and examined herein.
Priority
This application, 18/618,910, filed 03/27/2024, claims benefit of provisional application 63/456,305 filed on 03/31/2023. This priority is acknowledged and the claims examined herein are treated as having an effective filing date of 03/31/2023.
Information Disclosure Statement
The Information Disclosure Statement filed on 03/27/2024 is acknowledged and has been considered.
Claim Rejections - 35 USC § 102
The following is a quotation of the appropriate paragraphs of 35 U.S.C. 102 that form the basis for the rejections under this section made in this Office action:
A person shall be entitled to a patent unless –
(a)(1) the claimed invention was patented, described in a printed publication, or in public use, on sale, or otherwise available to the public before the effective filing date of the claimed invention.
(a)(2) the claimed invention was described in a patent issued under section 151, or in an application for patent published or deemed published under section 122(b), in which the patent or application, as the case may be, names another inventor and was effectively filed before the effective filing date of the claimed invention.
Claims 1, 2, 5, and 16 are rejected under 35 U.S.C. 102(a)(1) as being anticipated by Gupta et al. (2023). “Ultrasensitive lateral-flow assays via plasmonically active antibody-conjugated fluorescent nanoparticles”. Nature Biomedical Engineering, 7(12), 1556-1570., (published (02/02/2023)), (herein referred to as Gupta).
Regarding claim 1, Gupta teaches ultrasensitive lateral-flow assays using plasmonically active antibody-conjugated fluorescent nanoparticles (abstract). Gupta teaches the use of their lateral flow assay to measure analytes, specifically human interleukin-6 (IL-6), SARS-CoV-2 S1 antibodies, and SARS-CoV-2 antigen (nucleocapsid (N)) protein (page 1557, column 1, 3rd paragraph). Additionally, Gupta teaches that full-strip p-LFA components include: nitrocellulose membrane, FF80HP on poly styrene backing; sample pad, conjugate pad, and absorption pad (page 1567, column 1, 4th paragraph). Gupta teaches that to prepare the LFA strip, biorecognition element (for example, capture antibody) solution was pipetted onto the test membrane and dried at room temperature for 30 min (page 1565, column 2, 3rd full paragraph). Gupta teaches that for N protein p-LFA, the biorecognition element is immobilized on the detection zone (conjugate pad) and consists of streptavidin plasmonic-fluors (consisting of gold nanoparticles) bound to a N protein antibody conjugated to biotin that binds the antigen (page 1566, column 2, 3rd full paragraph; Supp Fig. 39).
Regarding claim 2, Gupta teaches that the first binding partner is biotin and the second binding partner is streptavidin (page 1557, column 2, 4th paragraph).
Regarding claim 5, Gupta teaches a housing that supports the membrane (“cassette”, page 1564, column 2, 1st full paragraph).
Regarding claim 16, Gupta teaches that both AuNPs and plasmonic fluors were functionalized with streptavidin, and biotinylated bovine serum albumin (BSA) was used as a capture ligand. LFA strips were then subjected to different known concentrations of streptavidin-conjugated AuNPs and plasmonic fluors for 20 min (Supplementary Fig. 5). Gupta teaches that the nanolabels flow along the nitrocellulose membrane by capillary force and get captured by the capture ligand, leading to the accumulation of nanoparticles at the test spot (page 1557, column 2, 2nd full paragraph). Gupta teaches that accumulation of sufficient number of nanolabels converts the colour at the test site to red, indicating a positive result and the presence of the target analyte (page 1557, column 2, 2nd full paragraph). The average greyscale intensity of the colorimetric signal at the test site with AuNPs and the fluorescence signal with plasmonic fluors monotonically increased with the concentration of the nanolabels (page 1557, column 2, 2nd full paragraph). In one embodiment, Gupta teaches that 1 µl IL-6 detection antibody-conjugated AuNPs and 1 µl anti-sheep IgG-conjugated AuNPs for test and control spot, respectively, were mixed with 98 µl of different concentrations of human IL-6 standard solutions (64 fg ml−1 to 5 ng ml−1) in 96-well plates to allow the binding of the analyte with the detection antibody-conjugated nanolabels (page 1566, column 1, 2nd full paragraph). Gupta also teaches that LFA strips in duplicates were then exposed to the sample and standard solutions for 20 min (page 1566, column 1, 2nd full paragraph).
Claim Rejections - 35 USC § 103
The following is a quotation of 35 U.S.C. 103 which forms the basis for all obviousness rejections set forth in this Office action:
A patent for a claimed invention may not be obtained, notwithstanding that the claimed invention is not identically disclosed as set forth in section 102, if the differences between the claimed invention and the prior art are such that the claimed invention as a whole would have been obvious before the effective filing date of the claimed invention to a person having ordinary skill in the art to which the claimed invention pertains. Patentability shall not be negated by the manner in which the invention was made.
Claims 3, 4, and 13 are rejected under 35 U.S.C. 103 as being unpatentable over Gupta as applied to claim 1 above, and further in view of Pronovost et al. (US 6,656,744 B2), (herein referred to as Pronovost).
The teachings of Gupta are incorporated herein.
Gupta teaches all the limitations of claim 1 as well as a labeled second antibody diffusively bound in a reagent zone on the immunoassay device, but does not teach that this labeled second antibody specifically binds to the antigen.
Regarding claims 3 and 4, Pronovost teaches one-step lateral flow assays wherein an analyte is applied to a test strip in a sample zone and detected in a capture zone, the invention provides means for improving the speed and accuracy of such assays (column 1, lines 10-14). Pronovost also teaches that the test strip has a sample-receiving zone, an optional labeling zone, and a capture zone. Pronovost teaches that the zones are constructed separately and placed into liquid communication; the capture or detection zone is abutted to an absorbent which enhances the flow of sample through the strip (column 4, lines 33-37). Pronovost teaches that the sample-receiving zone contains a first anti-analyte coupled to a member of an alternative specific binding pair, m1. The labelling zone contains a second anti-analyte coupled to the label where L denotes the detectable label; the capture zone contains the counterpart to m1, which is denoted m2. When analyte flows through the test strip, it picks up anti-analyte/m1 from the sample-receiving zone and labeled anti-analyte from the labeling zone and travels as a sandwich complex to the capture zone (column 7, lines 36-50). Pronovost also teaches that the sample can flow through a label pad which contains lyophilized predyed label complex containing antibody coupled to HRP (column 13, lines 20-25).
It would have been obvious to a person having ordinary skill in the art before the effective filing date to modify the immunoassay device of Gupta to use a labeled second antibody that specifically binds to the antigen, as taught by Pronovost, as a matter of simple substitution. Pronovost and Gupta both teach lateral flow immunoassay devices for rapid quantification of an analyte using label-bound antibodies. While Gupta uses plasmonically active antibody-conjugated fluorescent nanoparticles to achieve visualization and quantification of analyte, Pronovost uses a more conventional method using a labeled second antibody for a sandwich assay that is well known in the art, and one of ordinary skill could have substituted the method and the results would have been predictable.
A skilled artisan would have been motivated to make these modifications to the immunoassay device taught by Gupta because using the second antibody labeled using an enzyme such as HRP is more cost efficient and protocols for use are more well documented than using the plasmonically active antibody-conjugated fluorescent gold nanorods as taught by Gupta. One of ordinary skill would have a reasonable expectation of success making these modifications because use of an enzyme labeled second antibody that specifically binds to the antigen is a practice that is well-understood, routine and conventional in the field, and such antibodies and enzyme labels are commercially available.
Regarding claim 13, Pronovost teaches a method comprising applying the sample to the sample-receiving zone, allowing the sample to proceed through the labeling zone, if present, to the capture zone and assessing the capture zone for the presence, absence or amount of label in the capture zone. The analyte complexed or coupled to the label, or a labeled competitor of the analyte, is typically captured in a detection bar in the capture zone (column 2, lines 51-62).
Claims 6, 7, and 17 are rejected under 35 U.S.C. 103 as being unpatentable over Gupta as applied to claims 1, 2, 5 and 16 above, and further in view of O’Connor, T. P. (2015). ”SNAP assay technology”. Topics in companion animal medicine, 30(4), 132-138, (herein referred to as O’Connor).
The teachings of Gupta are incorporated herein.
Regarding claims 6, 7, and 17, Gupta teaches all the limitations of claims 5 and 16, but does not teach where the housing comprises a container comprising a liquid wash reagent and a container comprising a liquid substrate reagent comprising a substrate for the label. Gupta also does not teach the method steps of washing the reactive zone by adding the wash reagent to the membrane, and adding the substrate to the reactive zone.
However, O’Connor teaches the lateral flow immunoassay SNAP device which contains reagents needed to conduct the steps associated with the ELISA in-clinic with minimal hands-on time (page 132, column 1, 1st paragraph). O’Connor teaches a method and device where an enzyme-labeled conjugate (an antibody or antigen covalently attached to the enzyme horseradish peroxidase (HRPO)) is mixed with serum, plasma, or whole blood in a tube and added to the sample well of the SNAP device (page 132, column 2, 1st full paragraph). The sample-conjugate mixture then flows through the matrix, interacts with test and control spots deposited on the matrix, and reaches the activation circle in approximately 30-60 seconds (page 132, column 2, 1st full paragraph). O’Connor teaches that the device is then activated (by depressing or “snapping” the activator), which results in the release of wash buffer and substrate solution from reagent reservoirs contained within the device. Positive results are visualized by the formation of colored reaction products (page 132, column 2, 1st full paragraph; Fig. 2). More specifically, O’Connor teaches that activation of the SNAP device initiates additional steps in the ELISA procedure as described below: (1) Separate wash buffer and substrate solution reservoirs are punctured; wicks are forced into contact with the matrix and direct the flow of wash buffer and substrate solution to the matrix (page 133, column 2, 1st full paragraph).
It would have been obvious to a person having ordinary skill in the art before the effective filing date to modify the immunoassay device and method of Gupta to use housing comprising a container with a liquid wash reagent and a container comprising a liquid substrate reagent and performing a wash and substrate addition step, as taught by O’Connor, as a matter of combining known elements according to known methods to yield predictable results. Both Gupta and O’Connor teach lateral flow immunoassay device and methods using an antibody to bind and detect an antigen. Incorporating O’Connor’s wash buffer and substrate solution reagent reservoirs contained within the device would yield the predictable result of a wash and signal development step for the immunoassay without the user having to manually add the reagents.
A skilled artisan would have been motivated to make these modifications to the immunoassay device taught by Gupta because O’Connor teaches that the modification allows for timed, automatic, and sequential flow of sample, conjugate, and wash, substrate reagents in a simple easy-to-use device that can be run in clinic. Additionally, O’Connor teaches that a wash step removes sample debris and unreacted conjugate are efficiently removed from the matrix, which results in a clean white background so that false-positive results due to nonspecific reactions are almost nonexistent and weak-positive results can be easily detected (page 135, column 1, 2nd full paragraph). One of ordinary skill would have a reasonable expectation of success making these modifications because both Gupta and O’Connor are in the same field of lateral flow immunoassay devices and methods, O’Connor’s housing with reservoirs is generic and has been validated, and the use of wash and substrate steps/reagents with regard to lateral flow immunoassay devices is a practice that is well-understood, routine and conventional in the field.
Claims 8-12 are rejected under 35 U.S.C. 103 as being unpatentable over Gupta, Pronovost, and O’Connor in view of Zuk et al. (U.S. Patent No. 4208479).
In addition to the details of Gupta, Pronovost, and O’Connor discussed above, O’Connor also teaches a kit used to perform point-of-care lateral flow immunoassays s to measure antigens in a sample.
While Gupta, Pronovost, and O’Connor makes obvious the immunoassay device of claim 1 as discussed above, they do not recite all the reagents together in a kit.
However, Zuk et al. teaches the convenience and accuracy enhancement associated with combining all necessary reagents for an assay together in a kit (column 22, lines 20-68).
Therefore, it would have been obvious to one of ordinary skill in the art to assemble together the reagents (antibodies, binding partners, particles, labels, housing, liquid wash and substrate reservoirs, etc.) in the form of a kit, in order to create a reagent kit for a lateral flow immunoassay device for determining the presence of an antigen in a sample. A skilled artisan would have been motivated to combine all necessary reagents for a lateral flow immunoassay device for determining the presence of an antigen in a sample together in a kit, because kits are well known as being convenient and economical. A person of ordinary skill would have had a reasonable expectation of success in in assembling the reagents of the patented claims into kits as taught by Zuk because the creation and use of kits is a practice that is well-understood, routine and conventional in the field.
Claims 14 and 15 are rejected under 35 U.S.C. 103 as being unpatentable over Gupta in view of Pronovost as applied to claims 3, 4, and 13 above, and further in view of O’Connor.
The teachings of Gupta in view of Pronovost are incorporated herein.
Regarding claims 14 and 15, Gupta in view of Pronovost recites all of the limitations of claims 3, 4, and 13 of the instant application, but does not teach that the immunoassay device has a housing supporting the membrane and comprising a container comprising a wash reagent and a container comprising a substrate of the label, wherein the method comprises (i) washing the reactive zone by adding the wash reagent to the membrane, and (2) adding the substrate to the reactive zone.
However, as discussed above, O’Connor teaches the lateral flow immunoassay SNAP device and method of determining the presence or amount antigens or antibodies. Specifically, O’Connor teaches that activation of the SNAP device initiates additional steps in the ELISA procedure as described below: (1) Separate wash buffer and substrate solution reservoirs are punctured; wicks are forced into contact with the matrix and direct the flow of wash buffer and substrate solution to the matrix (page 133, column 2, 1st full paragraph).
It would have been obvious to a person having ordinary skill in the art before the effective filing date to modify the method of determining the presence or amount of an antigen in a liquid sample of Gupta in view of Pronovost to use housing comprising a container with a liquid wash reagent and a container comprising a liquid substrate reagent and performing a wash and substrate addition step, as taught by O’Connor, as a matter of combining known elements according to known methods to yield predictable results. Both Gupta, Pronovost, and O’Connor teach lateral flow immunoassay device using a labeled antibody to bind and detect an antigen in a liquid sample. Incorporating O’Connor’s wash buffer and substrate solution reagent reservoirs contained within the device, and performing a wash and substrate addition step, would yield the predictable result of a wash and signal development step for the immunoassay without the user having to manually add the reagents.
A skilled artisan would have been motivated to make these modifications to the immunoassay device taught by Gupta in view of Pronovost because O’Connor teaches that the modification allows for timed, automatic, and sequential flow of sample, conjugate, and wash, substrate reagents in a simple easy-to-use device that can be run in clinic. Additionally, a wash step removes sample debris and unreacted conjugate are efficiently removed from the matrix, which results in a clean white background so that false-positive results due to nonspecific reactions are almost nonexistent and weak-positive results can be easily detected (page 135, column 1, 2nd full paragraph). One of ordinary skill would have a reasonable expectation of success making these modifications because both Gupta, Pronovost, and O’Connor are in the same field of lateral flow immunoassay devices using labeled detection, O’Connor’s housing with reservoirs is generic and has been validated, and the use of wash and substrate steps/reagents with regard to lateral flow immunoassay devices is a practice that is well-understood, routine and conventional in the field.
Conclusion
The prior art made of record and not relied upon is considered pertinent to applicant's disclosure. Eisinger et al. (US 4,943,522 A) teaches a method and apparatus for conducting specific binding pair assays, such as immunoassays, using a porous membrane capable of non-bibulous lateral flow is used as assay substrate; a member of the binding pair is affixed in an indicator zone defined in the substrate; the sample is applied at a position distant from the indicator zone and permitted to flow laterally through the zone; any analyte in the sample is complexed by the affixed specific binding member, and detected (abstract).
For all the reasons discussed above, claims 1-17 are rejected and therefore no claims are allowed.
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/ALEXANDER J. HOFFMAN/ Examiner, Art Unit 1677
/BAO-THUY L NGUYEN/ Supervisory Patent Examiner, Art Unit 1677 July 27, 2026
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