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 .
Status of the Claims
Applicant’s submission filed 10 November 2025 has been entered. Claims 7-9, 12, 14-24, and 30 are pending. Claims 7-9, 12, 17-18, and 20-23 have been amended, while claims 13 and 26-29 have been cancelled without prejudice or disclaimer and claim 30 has been newly added. Therefore, prosecution on the merits continues for claims 7-9, 12, 14-24, and 30. All arguments have been fully considered with the status of each prior ground of rejection set forth below.
Status of Prior Rejections/Response to Arguments
RE: Rejection of claims 7-9, 12-24, and 26-29 under 35 USC 112(b)
The cancellation of claims 13 and 26-29 renders the rejection moot for those claims. For the remaining claims, Applicant has reverted the transitional phrase back to “comprising”, thus obviating the rejection of record.
Therefore, the rejection is withdrawn.
RE: Rejection of claims 7-9, 15-16, 19-20 under 35 USC 103 over Hayenga et al as evidenced by Furuta et al
Applicant has amended independent claim 7 to limit the microfluidic channel pattern to be selected from the group consisting of a circular spiral and an elliptical spiral, wherein the microfluidic channel has a cross-section that is about 0.5 mm to about 10 mm deep and about 0.5 mm to about 10 mm wide, thus obviating the rejection of record. It is also of note that Applicant’s amendments to independent claim 7 incorporates a limitation that was previously presented in claim 20, as well as narrows a limitation that had been previously presented within the independent claim.
Therefore, the rejection is withdrawn.
RE: Rejection of claims 7-9, 12, 15-16, and 19-21 under 35 USC 103 over Hayenga et al as evidenced by Furuta et al in view of Kuroda et al
Applicant has amended independent claim 7 to limit the microfluidic channel pattern to be selected from the group consisting of a circular spiral and an elliptical spiral, wherein the microfluidic channel has a cross-section that is about 0.5 mm to about 10 mm deep and about 0.5 mm to about 10 mm wide, thus obviating the rejection of record. It is also of note that Applicant’s amendments to independent claim 7 incorporates a limitation that was previously presented in claim 20, as well as narrows a limitation that had been previously presented within the independent claim.
Therefore, the rejection is withdrawn.
RE: Rejection of claims 7-9, 12, 15-17, and 19-24 under 35 USC 103 over Hayenga et al as evidenced by Furuta et al in view of Kuroda et al and Samborski et al
Applicant has amended independent claim 7 to limit the microfluidic channel pattern to be selected from the group consisting of a circular spiral and an elliptical spiral, wherein the microfluidic channel has a cross-section that is about 0.5 mm to about 10 mm deep and about 0.5 mm to about 10 mm wide, thus obviating the rejection of record. It is also of note that Applicant’s amendments to independent claim 7 incorporates a limitation that was previously presented in claim 20, as well as narrows a limitation that had been previously presented within the independent claim.
The Examiner also notes that Applicant did not specifically traverse the teachings of Samborski et al within the Remarks filed 10 November 2025.
Therefore, the rejection is withdrawn.
RE: Rejection of claims 7-9, 13-16, and 18-20 under 35 USC 103 over Hayenga et al as evidenced by Furuta et al in view of Dimov et al
The cancellation of claim 13 renders the rejection moot for that claim. For the remaining claims, Applicant has amended independent claim 7 to limit the microfluidic channel pattern to be selected from the group consisting of a circular spiral and an elliptical spiral, wherein the microfluidic channel has a cross-section that is about 0.5 mm to about 10 mm deep and about 0.5 mm to about 10 mm wide, thus obviating the rejection of record. It is also of note that Applicant’s amendments to independent claim 7 incorporates a limitation that was previously presented in claim 20, as well as narrows a limitation that had been previously presented within the independent claim.
The Examiner also notes that Applicant did not specifically traverse the teachings of Dimov et al within the Remarks filed 10 November 2025.
Therefore, the rejection is withdrawn.
RE: Rejection of claims 7-9, 13-16, 18-20, and 27 under 35 USC 103 over Hayenga et al as evidenced by Furuta et al in view of Dimov et al and Kuroda et al
The cancellation of claims 13 and 27 renders the rejection moot for those claim. For the remaining claims, Applicant has amended independent claim 7 to limit the microfluidic channel pattern to be selected from the group consisting of a circular spiral and an elliptical spiral, wherein the microfluidic channel has a cross-section that is about 0.5 mm to about 10 mm deep and about 0.5 mm to about 10 mm wide, thus obviating the rejection of record. It is also of note that Applicant’s amendments to independent claim 7 incorporates a limitation that was previously presented in claim 20, as well as narrows a limitation that had been previously presented within the independent claim.
Therefore, the rejection is withdrawn.
RE: Rejection of claims 7-9, 13-16, 18-20, and 26-29 under 35 USC 103 over Hayenga et al as evidenced by Furuta et al in view of Dimov et al and Kuroda et al
The cancellation of claims 13 and 26-29 renders the rejection moot for those claims. For the remaining claims, Applicant has amended independent claim 7 to limit the microfluidic channel pattern to be selected from the group consisting of a circular spiral and an elliptical spiral, wherein the microfluidic channel has a cross-section that is about 0.5 mm to about 10 mm deep and about 0.5 mm to about 10 mm wide, thus obviating the rejection of record. It is also of note that Applicant’s amendments to independent claim 7 incorporates a limitation that was previously presented in claim 20, as well as narrows a limitation that had been previously presented within the independent claim.
The Examiner also notes that Applicant did not specifically traverse the teachings of Dimov et al within the Remarks filed 10 November 2025.
Therefore, the rejection is withdrawn.
New Grounds of Rejection
Claim Interpretation
Applicant defines "substantial sedimentation" as corresponding to situation wherein at least
95% of the cells and other solid matter in the whole blood have settled, or are no longer suspended in the plasma serum, preferably at least 97%, more preferably at least 99% and most preferably at least 99.5%. See Paragraph [0024] of the Specification filed 25 February 2025.
Applicant has further defined “substantially devoid” to mean that none of the indicated substance is intentionally added to or present in the composition. See Paragraph [0023] of the Specification filed 25 February 2025.
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.
Claim 30 is 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.
Regarding claim 30: The instant claim recites the limitation “[t]he method of claim 7, further comprising a second purification step…”. As parent claim 7 does not specifically recite a first purification step, the ordinary artisan cannot readily determine the metes and bounds of the claim, thus rendering the scope of the claim indefinite. It is of note that this is an antecedent basis issue. See MPEP § 2173.05(e).
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 7, 9, 12, 15, 18-22, and 30 are rejected under 35 U.S.C. 103 as being unpatentable over Iriguchi (US 4424132 A) as evidenced by Furuta et al (TRANSFUSION, 2015, of record).
Iriguchi is considered prior art under 35 USC 102(a)(1) and 35 USC 102(a)(2). Furuta et al is considered prior art under 35 USC 102(a)(1).
Regarding claim 7: Iriguchi discloses an apparatus and method for separating blood components by means of sedimentation action due to gravitational force (Abstract).
As such, Iriguchi discloses a method of separating plasma from whole blood, wherein whole blood is introduced to a flat – or planar – microfluidic blood flow channel having a consistent depth of 0.5-10 mm and width of about 50 mm, allowed to sediment within the channel such that platelet-rich plasma is comprised within a first supernatant layer and blood corpuscles are comprised within a second sediment layer, and then removed via laminar flow to their respective exits (Columns 1-3, 5-8, 10-12; Examples 1, 4; Figures 1, 3).
Iriguchi further discloses that the microfluidic blood flow channel can also be situated as a spiral having a small pitch (Column 10).
Iriguchi does not disclose a planar spiral microfluidic blood flow channel having a cross-sectional width of about 0.5 mm to about 10 mm, as required by instant claim 7.
However, it would have been prima facie obvious to have modified the microfluidic device of Iriguchi such that the microfluidic blood flow channel is configured in a planar circular spiral pattern having a cross-sectional width of about 10 mm. One of ordinary skill in the art before the effective filing date of the invention would have recognized that the spiral microfluidic blood flow channel does not require the small pitch, as Iriguchi discloses that the separation efficiency of plasma from the whole blood is greatest when there is no inclination within the microfluidic channel (Table 5), and would have had a reasonable expectation of success given that Iriguchi reasonably suggests both the spiral and planar configurations of the microfluidic blood flow channel within embodiments of their invention. See MPEP § 2143(I)(G). Furthermore, the ordinary artisan would have been motivated to reduce the width of the microfluidic blood flow channel from about 50 mm to about 10 mm since the spiral configuration allows for a greater length of channel for sedimentation to occur while still maintaining the compact design, and would thus require a reduced channel width to maintain the optimal linear velocity of the blood flow (Columns 4-5, 10). See MPEP § 2143(I)(G) and 2144.05(II).
Consequently, Iriguchi renders obvious a method of separating plasma from whole blood, wherein whole blood is introduced to a planar microfluidic blood flow channel situated in a circular spiral pattern having a consistent depth of 0.5-10 mm and width of about 10 mm, allowed to sediment within the channel such that platelet-rich plasma is comprised within a first supernatant layer and blood corpuscles are comprised within a second sediment layer, and then removed via laminar flow to their respective exit ports. This therefore renders obvious the method of the instant claim.
Regarding claim 9: Following the discussion of claim 7, Iriguchi further discloses that the microfluidic blood flow channel is situated on a base (Columns 4-5, 9). This therefore reads on the method of the instant claim.
Regarding claims 12 and 21: Following the discussion of claim 7, Iriguchi further discloses that the microfluidic blood flow channel comprises an entry and exit that are fluidly connected to feed and discharge lines, respectively (claim 21) (Columns 5-8; Figures 1, 3). As the lines are tubes (Column 6), this therefore reads on the method of instant claim 12.
Regarding claims 15 and 30: Following the discussion of claim 7, Iriguchi further discloses a specific embodiment of the invention wherein, following the sedimentation of the whole blood via the microfluidic blood flow channel, the first supernatant layer comprising the platelet-rich plasma is introduced to an affinity-binding column to further purify the plasma of any remaining cells or waste (claim 30) (Columns 7-8; Figure 3). As this embodiment avoids the use of anything requiring centrifugal forces and membranous filtration devices, this therefore reads on the method of instant claim 15.
Regarding claim 18: Following the discussion of claim 7, Iriguchi further discloses that the time in which the blood is in the channel, and thereby in which substantial sedimentation is effected, is 15-60 minutes (Table 4). This therefore reads on the method of the instant claim. See MPEP § 2144.05(I).
Regarding claim 19: As aforementioned in the discussion of claim 7, Iriguchi discloses that the supernatant layer comprises platelet-rich plasma. As plasma inherently comprises bacterial – or prokaryotic – cells (Furuta et al, Figure 2), this therefore reads on the method of the instant claim.
Regarding claim 20: Following the discussion of claim 7, Iriguchi further discloses that the cross-section of the microfluidic blood channel is rectangular, or at the very least polygonal (Figures 1, 6). This therefore reads on the method of the instant claim.
Regarding claim 22: Following the discussion of claim 7, Iriguchi further discloses that pumps are utilized to remove the separated sedimentation layer from the supernatant layer (Columns 7-8, 10; Example 1; Figure 3).
Claims 7-9, 12, 14-16, 18-22, and 30 are rejected under 35 U.S.C. 103 as being unpatentable over Iriguchi (US 4424132 A) as evidenced by Furuta et al (TRANSFUSION, 2015, of record) in view of Dimov et al (US 2012/0276641 A1, of record).
The discussion of Iriguchi regarding claims 7 and 30 can be observed above and is relied upon
herein, the content of which is incorporated in its entirety. Iriguchi as evidenced by Furuta et al render obvious claims 7, 9, 12, 15, 18-22, and 30. Dimov et al is considered prior art under 35 USC 102(a)(1) and 35 USC 102(a)(2).
Regarding claims 8 and 14: As aforementioned in the discussion of claims 7 and 30 above, Iriguchi teaches a method of separating plasma from whole blood, wherein whole blood is introduced to a planar microfluidic blood flow channel situated in a circular spiral pattern having a consistent depth of 0.5-10 mm and width of about 10 mm, allowed to sediment within the channel such that platelet-rich plasma is comprised within a first supernatant layer and blood corpuscles are comprised within a second sediment layer, and removed via laminar flow to their respective exit ports, wherein the separated supernatant layer comprising the platelet-rich plasma is then introduced to an affinity-binding column to further purify the plasma of any remaining cells or waste.
Iriguchi does not disclose that the removed supernatant layer is high pure plasma serum, as required by instant claim 8.
Dimov et al, however, disclose a device for blood-plasma separation and plasma-based blood analysis (Abstract).
As such, Dimov et al disclose the separation of plasma from whole blood, wherein a sample of whole blood is administered to an inlet of a microfluidic device and allowed to gravitationally sediment such that the plasma separates from and is situated above the other blood components (Paragraph [0008]). Following separation, Dimov et al further disclose that the plasma is able to pass downstream where it subsequently undergoes an affinity binding assay (Paragraphs [0021], [0026]). Dimov et al disclose that this affinity binding assay includes the capturing of proteins, agents or antigens, and other molecules or compounds which are present within the plasma (Paragraph [0026]). Such other molecules include platelets, which are still suspended within the plasma following the sedimentation process (Paragraphs [0034], [0038], [0040]-[0042]). Once captured, the resulting assay may then be analyzed using a variety of techniques such as a luminescence response of the assay to excitation, or with different analytical techniques (Paragraph [0026]).
Dimov et al further disclose that the plasma extracted from the outlet of the microfluidic device is pure plasma (Paragraphs [0041], [0059]).
Therefore, it would have been prima facie obvious to modify the method of Iriguchi such that the collected supernatant layer is highly pure plasma serum. One of ordinary skill before the effective filing date of the invention would have been motivated to ensure that the collected plasma sample is free from any other blood components, including platelets, and would have had a reasonable expectation of success based on the combined disclosures of Iriguchi (Columns 7-8; Figure 3) and Dimov et al (Paragraphs [0034], [0040]-[0042]), especially given both are concerned with the sedimentation-dependent separation of plasma from whole blood. See MPEP § 2143(I)(G).
Consequently, Iriguchi as modified by Dimov et al render obvious a method of separating plasma from whole blood, wherein a portion of the removed supernatant layer is highly pure plasma serum (claim 8). As the supernatant layer is subject to a purification step that utilizes affinity binding to remove all extraneous blood components, and thereby undergoes an assay that involves the binding – or a reaction – between any remaining components in the plasma and the coated particles, this therefore renders obvious the method of instant claim 14.
Regarding claim 16: Following the discussion of claim 7, Iriguchi is silent to the addition of lysing chemicals to the initial whole blood sample or within the sedimentation process. The disclosure of Iriguchi is also silent to the presence of hemoglobin within the separated plasma.
Iriguchi does disclose the addition of anti-coagulants to the whole blood sample (Columns 3, 10).
Iriguchi does not disclose that the supernatant layer comprising the plasma is substantially devoid of anti-coagulants, as required by instant claim 16.
However, it would have been prima facie obvious for the highly pure plasma rendered obvious by Iriguchi as modified by Dimov et al to be substantially devoid of the anti-coagulants. One of ordinary skill before the effective filing date of the invention would have been motivated to ensure that the highly pure plasma is devoid of any soluble toxic, waste, or non-plasma substances (Iriguchi: Column 8), and would have had a reasonable expectation of success based on the combined disclosures of Iriguchi (Columns 7-8; Figure 3) and Dimov et al (Paragraphs [0034], [0040]-[0042]), especially given both are concerned with the sedimentation-dependent separation of plasma from whole blood. See MPEP § 2143(I)(G).
Consequently, Iriguchi as modified by Dimov et al render obvious a method of separating plasma from whole blood, wherein the highly pure plasma comprised within the separated supernatant layer is substantially devoid of lysing chemicals, anti-coagulants, and hemoglobin. This therefore renders obvious the method of the instant claim.
Claims 7, 9, 12, 15, 17-24, and 30 are rejected under 35 U.S.C. 103 as being unpatentable over Iriguchi (US 4424132 A) as evidenced by Furuta et al (TRANSFUSION, 2015, of record) in view of Samborski et al (Eng Life Sci, 2015, of record).
The discussion of Iriguchi regarding claims 7, 12, and 21 can be observed above and is relied upon herein, the content of which is incorporated in its entirety. Iriguchi as evidenced by Furuta et al render obvious claims 7, 9, 12, 15, 18-22, and 30. Samborski et al is considered prior art under 35 USC 102(a)(1).
Regarding claims 17 and 23-24: Following the discussion of claims 7, 12, and 21 above, Iriguchi further discloses the use of pumps to both feed the whole blood sample that has been buffered with plasma into the microfluidic blood flow channel, as well as remove the separated supernatant and sedimentation layers through their respective discharge lines (Columns 5-8, 10; Example 1; Figure 3).
Iriguchi fails to disclose the use of syringe pumps to remove the layers from the microfluidic channel, as required by instant claims 17 and 23.
Samborski et al, however, disclose a microfluidic system that uses sedimentation to extract plasma from undiluted blood and integrates execution of liquid assays on the extracted material (Abstract).
As such, Samborski et al disclose that the microfluidic system is comprised of a microfluidic and two syringe pumps, wherein whole blood is first deposited into an inlet of a channel comprised within the microfluidic via syringe pump and allowed to gravitationally sediment to the bottom of the channel (Page 334, 2.3 Experimental setup; Pages 334-335, 3.1 Optimization of separation). During the sedimentation process, plasma comprised within the whole blood – which remains situated above the other blood components that have settled to the bottom of the channel – slowly flows out of the chamber, drawn by capillary forces. At that time, the second syringe pump is turned on in withdrawal mode to create negative pressure, thereby drawing the plasma through the channel towards the outlet to be collected (Page 334, 2.3 Experimental setup; Page 336, 3.2 Generation of plasma-reagent segment; Figure 1).
Therefore, it would have been prima facie obvious to substitute the pumps of Iriguchi with the syringe pumps of Samborski et al, as doing so would have been a simple substitution of one pump for another. See MPEP § 2143(I)(B). One of ordinary skill in the art before the effective filing date of the invention would have recognized that the two pumps are functionally comparable, as they are both utilized to insert the whole blood sample to the microfluidic channel and withdraw the separated layers from the microfluidic channel, and thereby would have been able to substitute the pumps with predictable results.
Consequently, Iriguchi as modified by Samborski et al render obvious a method of separating plasma from whole blood, wherein the supernatant layer comprising the plasma is extracted from the microfluidic blood flow channel through the use of a syringe pump (claim 17). As the supernatant layer is simultaneously being eluted from the first syringe pump via the continuous stream of the whole blood sample buffered with plasma (claim 24) and the syringe pumps associated with the discharge lines, this therefore renders obvious the method of instant claim 23.
Conclusion
Applicant's amendment necessitated the new ground(s) of rejection presented in this Office action. Accordingly, THIS ACTION IS MADE FINAL. See MPEP § 706.07(a). Applicant is reminded of the extension of time policy as set forth in 37 CFR 1.136(a).
A shortened statutory period for reply to this final action is set to expire THREE MONTHS from the mailing date of this action. In the event a first reply is filed within TWO MONTHS of the mailing date of this final action and the advisory action is not mailed until after the end of the THREE-MONTH shortened statutory period, then the shortened statutory period will expire on the date the advisory action is mailed, and any nonprovisional extension fee (37 CFR 1.17(a)) pursuant to 37 CFR 1.136(a) will be calculated from the mailing date of the advisory action. In no event, however, will the statutory period for reply expire later than SIX MONTHS from the mailing date of this final action.
Any inquiry concerning this communication or earlier communications from the examiner should be directed to ALYSSA G WESTON whose telephone number is (571)272-0337. The examiner can normally be reached Monday-Thursday 8AM - 4PM (CT); Friday 8AM - 11AM (CT).
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If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Christopher Babic can be reached at (571) 272-8507. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
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/ALYSSA G WESTON/Examiner, Art Unit 1633
/CHRISTOPHER M BABIC/Supervisory Patent Examiner, Art Unit 1633