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 .
Election/Restrictions
Claims 37, 38, 41-43, and 49 are withdrawn from further consideration pursuant to 37 CFR 1.142(b) as being drawn to a nonelected Group 2, there being no allowable generic or linking claim. Election was made without traverse in the reply filed on 10/27/2025.
Status of the Claims
Claims 1-4, 8, 10, 12, 14, 19, 21, 22, 28, 33, and 35 are pending and examined herein.
Priority
This application, filed 02/23/2023, claims benefit of PRO 63/313,697, filed 02/24/2022. This benefit is acknowledged and the claims examined herein are treated as having an effective filing date of 02/24/2022.
Information Disclosure Statement
The Information Disclosure Statement filed 03/08/2024 is acknowledged and has been considered.
Claim Rejections - 35 USC § 112
The following is a quotation of 35 U.S.C. 112(b):
(b) CONCLUSION.—The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the inventor or a joint inventor regards as the invention.
The following is a quotation of 35 U.S.C. 112 (pre-AIA ), second paragraph:
The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the applicant regards as his invention.
Claims 1, 3, and 14 are rejected under 35 U.S.C. 112(b) or 35 U.S.C. 112 (pre-AIA ), second paragraph, as being indefinite for failing to particularly point out and distinctly claim the subject matter which the inventor or a joint inventor (or for applications subject to pre-AIA 35 U.S.C. 112, the applicant), regards as the invention.
Claim 1 recites “performing immunomagnetic enrichment to generate an electrochemical signal”. It is unclear how “performing immunomagnetic enrichment” is defined. The Specification states that “performing immunomagnetic enrichment comprises placing the microfluidic chip on a magnet” however, it is not clear how that generates an electrochemical signal, as recited in claim 1. For the purposes of compact prosecution, this will be considered to cover any step in a method using a magnet on the chip to affect the magnetic beads to facilitate enrichment in the assay; however, appropriate clarification is required.
Claim 3 recites “wherein the sample to DMBs ratio is about 10:1 to about 20:1”; however, It is unclear what components “the sample to DMBs ratio” refers to. In this case, does “the sample” refer to the number of samples, the concentration of the sample, the volume of the sample, or some other characteristic of the sample? Does “DMBs” refer to the number of different DMBs, the concentration of DMBs, the number of DMBs in the mixture, the volume of the DMBs, the volume of the liquid containing the DMBs, or some other characteristic? For purposes of compact prosecution, the sample to DMB ratio will be considered to be a ratio of the volume of liquid containing the beads to the liquid volume of the sample, consistent with an embodiment in the Specification (p. 74, lines 1-3); however, appropriate clarification is required.
Claim 14 is indefinite for depending on claim 13, which has been cancelled. For purposes of compact prosecution, claim 14 will be interpreted as being dependent on claim 1; however, appropriate correction is required.
Claim Rejections - 35 USC § 103
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.
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.
The factual inquiries for establishing a background for determining obviousness under 35 U.S.C. 103 are summarized as follows:
1. Determining the scope and contents of the prior art.
2. Ascertaining the differences between the prior art and the claims at issue.
3. Resolving the level of ordinary skill in the pertinent art.
4. Considering objective evidence present in the application indicating obviousness or nonobviousness.
This application currently names joint inventors. In considering patentability of the claims the examiner presumes that the subject matter of the various claims was commonly owned as of the effective filing date of the claimed invention(s) absent any evidence to the contrary. Applicant is advised of the obligation under 37 CFR 1.56 to point out the inventor and effective filing dates of each claim that was not commonly owned as of the effective filing date of the later invention in order for the examiner to consider the applicability of 35 U.S.C. 102(b)(2)(C) for any potential 35 U.S.C. 102(a)(2) prior art against the later invention.
Claims 1-4, 8, 10, 12, 19, 21-22, 28, 33, and 35 are rejected under 35 U.S.C. 103 as being unpatentable over Otieno et al., “On-line protein capture on magnetic beads for ultrasensitive microfluidic immunoassays of cancer biomarkers” Biosensors and Bioelectronics (published 10/08/2013, referred to herein as Otieno) in view of Li et al., “AC Electrothermal Flow-Enhanced, Label-Free Immunosensor for Rapid Electrochemical Sensing” Proceedings of the 15th Annual IEEE International Conference (published 09/27/2020, IDS dated 03/08/2024, referred to herein as Li) as evidenced by Krause et al., “Rapid Microfluidic Immunoassays of Cancer Biomarker Proteins Using Disposable Inkjet-Printed Gold Nanoparticle Arrays” ChemistryOPEN (published 08/2013, referred to herein as Krause) and Centi et al., “A disposable immunomagnetic electrochemical sensor based on functionalised magnetic beads and carbon-based screen-printed electrodes (SPCEs) for the detection of polychlorinated biphenyls (PCBs)” Analytica Chimica Acta (published 03/12/2005, referred to herein as Centi).
Regarding claim 1, Otieno teaches a microfluidic method for detecting a target protein (p. 269, col. 1, para. 4, lines 2-7) comprising contacting the sample with dual-labelled magnetic beads conjugated to a capture antibody and an HRP reporter enzyme in a microfluidic chip (p. 270, col. 1, para. 6, line 3 – col. 2, para. 1, line 1), mixing the sample and beads (p. 270, col. 2, para. 1, lines 1-5), performing immunomagnetic enrichment with a magnet (p. 271, col. 2, para. 2, lines 4-10), and detecting the target protein by measuring levels of the reporter (p. 272, col. 1, para. 1, lines 1-4).
Regarding claim 2, Otieno teaches that the capture antibody is monoclonal (p. 269, col. 2, para. 2, lines 13-15).
Regarding claim 3, Otieno teaches a sample to bead volume ratio of 5:40, or 1:8. However, it would have been prima facie obvious for one of ordinary skill in the art before the effective filing date of the claimed invention to perform routine optimization of the components in the claimed invention to make and use the claimed invention. As noted in In re Aller, 105 USPQ 233 at 235, more particularly, where the general conditions of a claim are disclosed in the prior art, it is not inventive to discover the optimum or workable ranges by routine experimentation. Routine optimization is not considered inventive and no evidence has been presented that arriving at the claimed sample to bead ratio was anything other than routine, that the properties of the ratio from the optimization has any unexpected properties, or that the results should be considered unexpected in any way as compared to the closest prior art. Optimization of parameters is a routine practice that would be obvious for the artisan to employ. See MPEP § 2144.05. The artisan would have had a reasonable expectation of success based on the cumulative disclosures of Krause et al., “Rapid Microfluidic Immunoassays of Cancer Biomarker Proteins Using Disposable Inkjet-Printed Gold Nanoparticle Arrays” ChemistryOPEN (published 08/2013, referred to herein as Krause) and Centi et al., “A disposable immunomagnetic electrochemical sensor based on functionalised magnetic beads and carbon-based screen-printed electrodes (SPCEs) for the detection of polychlorinated biphenyls (PCBs)” Analytica Chimica Acta (published 03/12/2005, referred to herein as Centi). Krause teaches an electrochemical microfluidic immunoassay for detecting an analyte using a sample to bead ratio of 1:12 (Krause supplemental material, p. S8, para. 2, lines 3-7) and Centi teaches an electrochemical microfluidic immunoassay for detecting an analyte using a sample to bead ratio of about 20:1 (Centi, p. 207, col. 2, para. 3, lines 1-2). An artisan would recognize that when doing immunodetection using beads in a sample, that the relative volumes of the beads and sample need to be optimized in order to maximize the number of beads that can bind to the target analyte within the analyte concentration range. As taught by Krause and Centi, the range of potential sample to bead ratios used in electrochemical microfluidic immunoassay is wide and needs to be optimized. An artisan would recognize that doing so increases the sensitivity of the assay based on the target analyte concentration range.
Regarding claim 4, Otieno teaches contacting the sample with the beads for 30 minutes, which is considered to be about 40 minutes (p. 270, col. 2, para. 1, lines 3-5).
Regarding claim 8, Otieno teaches using a syringe pump to load liquids into the chip (Figure 1, p. 270, col. 1, para. 6, lines 4-6, “injected”).
Regarding claim 10, Otieno teaches the reporter generates an electrochemical signal (p. 270, col. 2, para. 1, lines 17-19).
Regarding claim 12, Otieno teaches the use of horseradish peroxidase as a reporter (p. 270, col. 1, para. 4, lines 1-3), which is a chemiluminescent reporter as described in the instant Specification (p. 6, lines 1-3).
Regarding claim 19, Otieno teaches detecting amperometric current (p.270, col. 2, para. 1, lines 17-19).
Regarding claim 28, Otieno teaches a method that does not comprise centrifuging the sample (p. 270, col. 1, para. 6 – col. 2, para. 1).
Regarding claim 33, Otieno teaches that “The assay requires 30 minutes” (p. 273, col. 2, para. 3, lines 7-8).
Regarding claim 35, Otieno teaches using a sample volume of 5µl (p. 270, col. 1, para. 6, lines 6-7).
However, Otieno does not teach using AC electrothermal flow (ACEF) to mix the sample (claim 1) applied at 200kHz and 25 Vpp (claim 21) for about 5 minutes (claim 22).
Li teaches a method of target protein electrochemical detection in a chip using beads and ACEF for mixing sample and beads (p. 1, col. 2, para. 2, lines 1-3).
Regarding claim 1, Li teaches applying ACEF to mix the sample (p. 555, col. 2, para. 3, lines 1-7). Li teaches that “ACEF-induced mixing can significantly reduce the time for immunocomplex formation compared with incubation-based antigen-antibody binding while also resulting in a higher detection sensitivity due to electrochemical flow-induced removal of nonspecific species from the sensor surface.” (p. 558, col. 1, para. 3, lines 4-9).
Regarding claim 21, Li teaches ACEF applied as 200 kHz (p. 557, col. 1, para. 2, lines 1-6). Li teaches that the level of Vpp was optimized between 1-10 (Figure 6a. p. 557, col. 2, para. 1, lines 1-2). However, it would have been prima facie obvious for one of ordinary skill in the art before the effective filing date of the claimed invention to perform routine optimization of the Vpp level in the claimed invention to make and use the claimed invention. As noted in In re Aller, 105 USPQ 233 at 235, more particularly, where the general conditions of a claim are disclosed in the prior art, it is not inventive to discover the optimum or workable ranges by routine experimentation. Routine optimization is not considered inventive and no evidence has been presented that arriving at the claimed 25 Vpp was anything other than routine, that the properties of the 25 Vpp from the optimization has any unexpected properties, or that the results should be considered unexpected in any way as compared to the closest prior art. Optimization of parameters is a routine practice that would be obvious for the artisan to employ. See MPEP § 2144.05. The artisan would have had a reasonable expectation of success based on the cumulative disclosures of Li and Lu et al., “AC Electrokinetics of Physiological Fluids for
Biomedical Applications” Journal of Lab. Automation (published December 2015, referred to herein as Lu). As taught by Li, the value of Vpp should be optimized for the assay (p. 557, col. 2, para. 1, lines 1-2) and Lu teaches that up to 30 Vpp can be used to manipulate biological samples (p. 615, col. 1, para. 1, lines 1-3). Based on the cumulative teachings of Li and Lu, it would have been obvious to optimize the Vpp levels for the assay between 1 and 30 Vpp.
Regarding claim 22, Li teaches mixing the sample for 5 minutes using ACEF (p. 555, col. 2, para. 3, lines 1-6).
It would have been obvious to one of ordinary skill in the art to modify the method taught by Otieno by including the use of ACEF mixing taught by Li. An artisan would have been motived to make this modification because the use of ACEF increases the specificity and formation speed of antigen-antibody immunocomplexes in bead-based immunoassays, as taught by Li. An artisan would have a reasonable expectation of success because the methods taught by Otieno and Li both are directed toward the detection of a target protein using immobilized antibodies and antibody-conjugated beads in a sandwich-type method on a microfluidic chip. Li has shown that ACEF can be successfully incorporated into these types of assays.
Regarding claim 33, the combined teachings of Otieno and Li would result in a 5 minute mixing step and a 15 minute capture step (Otieno, p. 270, col. 2, para. 1, lines 13-17), which is less than 30 total minutes.
Claims 14 is rejected under 35 U.S.C. 103 as being unpatentable over Otieno in view of Li as applied to claim 1 above, and further in view of Hou et al., “A colorimetric and electrochemical immunosensor for point-of-care detection of enterovirus 71” Biosensors and Bioelectronics (published 07/14/2017, IDS dated 03/08/2024, referred to herein as Hou).
The teachings of Otieno in view of Li, as discussed above regarding claim 1, are incorporated herein.
Regarding claim 14, Otieno teaches a method comprising a bead conjugated to an antibody and HRP (p. 270, col. 1, para. 4, lines 1-3). In this case, the antibody is considered to be conjugated to HRP through conjugation to the bead.
However, Otieno in view of Li does not teach detecting a colorimetric signal.
Regarding claim 14, Hou teaches a method of protein detection using a magnetic bead conjugated to HRP and a detection antibody (Scheme 1, p. 187, col. 2, para. 3, lines 1-2). Hou teaches that these beads can be used to detect a colorimetric signal (p. 187, col. 1, para. 2, lines 5-13). Hou teaches that the colorimetric detection of the protein is convenient because it can be read without any instruments and enables easy point-of-care detection (p. 189, col. 1, para. 1, lines 5-11).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to modify the method taught by Otieno in view of Li by detecting the protein using colorimetric detection as taught by Hou. An artisan would have been motivated to make this modification because, as taught by Hou, colorimetric detection is convenient and enables point-of-care detection without instrumentation. An artisan would have had a reasonable expectation of success in making this modification because the methods taught by Otieno and Hou both use beads conjugated to the detection antibody and an HRP reporter which, as taught by Hou, can be used for both colorimetric and electrochemical detection.
Conclusion
No claims are allowable.
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/C.E./Examiner, Art Unit 1677
/BAO-THUY L NGUYEN/Supervisory Patent Examiner, Art Unit 1677