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 .
Election/Restrictions
Applicant’s election without traverse of group (1-12) in the reply filed on 4/24/2026 is acknowledged.
Information Disclosure Statement
The information disclosure statement (IDS) submitted on 7/25/2023 and 3/4/2026 are in compliance with the provisions of 37 CFR 1.97. Accordingly, the information disclosure statement is being considered by the examiner.
Claim Status
Claims 1-14 are pending with claims 1-12 being examined and claims 13-14 are withdrawn.
Claim Objections
Claim 8 is objected to because of the following informalities: claim 8 reads “the channels” should read as “the plurality of channels” in line 2. Appropriate correction is required.
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 3 and 8 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 3 recites the limitation "wherein a length of a channel cross-section of the inflow part in the second direction is formed to be smaller than a length of a channel cross-section of the area where the lift force acts in the second direction" in lines 1-5. The limitation is unclear as to how the length is determined. Specifically, the Applicant is comparing the “cross-section of the inflow part in the second direction” to the “cross-section of the area where the lift force acts in the second direction”. However, the “lift force” separates the particles in the fluid in the first direction, and the “action of flow in the channel” separates the particles in the second direction. Thus, it is unclear as to how the length is determined with respect to the lift force acting on the second direction when claim 1 teaches that the second direction is dependent upon the flow through the channel. For purpose of prosecution, the Examiner interprets that any part along the channel where particles separate in the second direction reads on the “length of a channel cross-section of the area where the lift force acts in the second direction”.
Claim 8 recites the limitation “wherein the channels are formed in the inflow part within a range of 0.1 to 0.9 in a height direction, which is calculated from a center of the area where the lift force acts in the microchannel in the height direction” in lines 1-5. The limitation is unclear because the Applicant does not specify the unit of measurement. Thus, it is unclear as to what the height would be. In the instant specification the channel height is 100 μm (Instant specification; para [45]), therefore the range in the height direction of 0.1 to 0.9 is interpreted to be in “mm”.
Claim Rejections - 35 USC § 102
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 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 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.
Claim(s) 1-7 and 11-12 are rejected under 35 U.S.C. 102(a)(1) as being anticipated by Han et al (US 20150238963 A1; hereinafter “Han”; already of record on IDS filed 7/25/2023).
Regarding claim 1, Han teaches a microfluidic device comprising:
a microchannel (Han; para [94]; micro-fluidic device 900 that includes a curvilinear microchannel) configured to separate particles contained in a fluid at least in a first direction according to a size of the particles by an action of lift force and separate the particles in a second direction by an action of flow in a channel cross-section (Han; para [30, 65, 75, 94]; At certain flow rates, the larger particle can focus along the inner wall influenced by both Dean flow and inertial lift, while the smaller particles tend to get trapped in the vortex center at the outer side); and
an inflow part configured to allow the fluid to flow into an area where the lift force acts, the inflow part being provided at an upstream from the area where the lift force acts in the microchannel (Han; Fig. 9A; para [94]; introducing the mixture into at least one inlet (not shown) of a micro-fluidic device 900…a flow rate that isolates particles along portions of the cross-section of the microchannel based on particle size, wherein larger particles 970 flow along the radially inner side 910 of the microchannel to a first (inner) outlet 950 and smaller particles 980 flow along other portions of the microchannel to at least one other (outer) outlet 960, thereby size separating the particles from the mixture), wherein
a length of a channel cross-section of the inflow part in the first direction is formed to be smaller than a length of a channel cross-section of the area where the lift force acts in the first direction (Han; Fig. 9A; para [26, 169]; all the microfluidic channels used in these experiments were designed to be 8-loops single-inlet two-outlet spiral with radius increasing from 8 mm 24 mm to provide sufficient length for the particle migration). The Examiner notes that the Applicant does not specify the where along the channel of the inflow part the cross-section is taken. Therefore, Han teaches the claimed limitation as Han teaches the requires radius/length of the channel to increases in order for the Dean vortices to be generated in the curvilinear microchannel (Han; para [169]).
Regarding claim 2, Han teaches the microfluidic device according to claim 1, wherein the inflow part is provided to allow the fluid to flow in the same direction as a flow direction of the fluid in the area where the lift force acts (Han; Fig. 9A; para [94]).
Regarding claim 3, Han teaches the microfluidic device according to claim 1, wherein a length of a channel cross-section of the inflow part in the second direction is formed to be smaller than a length of a channel cross-section of the area where the lift force acts in the second direction (Han; Fig. 9A; para [26, 169]; all the microfluidic channels used in these experiments were designed to be 8-loops single-inlet two-outlet spiral with radius increasing from 8 mm 24 mm to provide sufficient length for the particle migration). The Examiner notes that the Applicant does not specify the where along the channel of the inflow part the cross-section is taken. Therefore, Han teaches the claimed limitation as Han teaches the requires radius/length of the channel to increases in order for the Dean vortices to be generated in the curvilinear microchannel (Han; para [169]). The length of the channel increases overall, thus increasing in both the “first direction” and “the second direction”.
Regarding claim 4, Han teaches the microfluidic device according to claim 3, wherein a shape of the channel cross-section in the inflow part is formed to be a same shape as a shape of the channel cross-section in the area where the lift force acts (Han; Fig. 9A; para [14, 15, 94]; a curvilinear microchannel having a trapezoidal cross section). The Applicant does not specify where along the inflow part or the area where the lift force acts that the cross-section is taken. Thus, the Examiner interprets that the shape of the channel cross-section in the inflow part and the shape of the channel cross-section in the area where the lift force acts is the same as seen in the cross-section A-A and B-B.
Regarding claim 5, Han teaches the microfluidic device according to claim 1, wherein the inflow part is formed such that a channel cross-sectional area on a side where the fluid flows is larger than a channel cross-sectional area on a side where the fluid flows into the area where the lift force acts (Han; Fig. 9A; para [30, 65, 75, 94]). The Examiner notes that the Applicant does not specify the where along the channel of the inflow part the cross-section is taken. Therefore, Han teaches the claimed limitation as seen in Fig. 9A. Specifically, the inflow part has a larger cross-section comparted to the outer outlet which is the channel where the smaller particles separated by the lift force are removed.
Regarding claim 6, Han teaches the microfluidic device according to claim 1, wherein the inflow part is formed such that the channel cross-sectional area on the side where the fluid flows into the area where the lift force acts is equal to or less than 90% of the channel cross-sectional area in the area where the lift force acts (Han; Fig. 9A; para [26, 169]; all the microfluidic channels used in these experiments were designed to be 8-loops single-inlet two-outlet spiral with radius increasing from 8 mm 24 mm to provide sufficient length for the particle migration). The Examiner notes that the Applicant does not specify the where along the channel or the inflow part the cross-section is taken. Therefore, Han teaches the claimed limitation as Han teaches the requires radius/length of the channel to increases in order for the Dean vortices to be generated in the curvilinear microchannel (Han; para [169]). Han teaches the channel length increasing, thus there is a portion of the channel and the inflow part where the cross-section of both areas is equal to or less than 90% of one another.
Regarding claim 7, Han teaches the microfluidic device according to claim 1, wherein the inflow part is formed with a plurality of channels, which are arranged in a vertical direction, and allows the fluid to flow from each of the channels into the area where the lift force acts (Han; para [79]; the micro-fluidic device includes a single inlet, 2 inlets, 3 inlets, 4 inlets, 5 inlets, 6 inlets, 7 inlets, 8 inlets, 9 inlets, or 10 or more inlets). The examiner notes that the “vertical arrangement” would be met based on the orientation of the microfluidic device.
Regarding claim 11, Han teaches the microfluidic device according to claim 1, wherein the microchannel receives an inflow of a fluid that contains cells having various sizes, separates the cells contained in the fluid in the first direction by the action of the lift force, and separates the cells in the second direction by the action of the flow in the channel cross-section (Han; para [30, 65, 75, 94]; At certain flow rates, the larger particle can focus along the inner wall influenced by both Dean flow and inertial lift, while the smaller particles tend to get trapped in the vortex center at the outer side…a flow rate that isolates particles along portions of the cross-section of the microchannel based on particle size, wherein larger particles 970 flow along the radially inner side 910 of the microchannel to a first (inner) outlet 950 and smaller particles 980 flow along other portions of the microchannel to at least one other (outer) outlet 960, thereby size separating the particles from the mixture).
Regarding claim 12, Han teaches the microfluidic device according to claim 1, wherein the microchannel receives an inflow of a fluid that contains nucleated cells and non-nucleated cells contained in blood, separates the nucleated cells from the non-nucleated cells contained in the fluid in the first direction by the action of the lift force, and separates the nucleated cells from the non-nucleated cells in the second direction by the action of the flow in the channel cross-section (Han; para [203]; Han describes separating WBC and platelets).
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 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.
Claim 8 is rejected under 35 U.S.C. 103 as being unpatentable over Han.
Regarding claim 8, Han teaches the microfluidic device according to claim 7, wherein the channels are formed in the inflow part within a range of 0.1 to 0.9 in a height direction, which is calculated from a center of the area where the lift force acts in the microchannel in the height direction (Han; para [87]). The Examiner notes that the channels would be within the range of one another depending on the orientation of the inlets. The claimed range overlaps or falls within the prior art range; in cases where the claimed range overlaps or falls within the prior art range, a prima facie case of obviousness of the range exists. It would have been obvious to one having ordinary skill in the art to have selected the height in the range of range of 0.1 to 0.9mm that corresponds to the claimed range. See MPEP 2144.05(I).
Claims 9-10 are rejected under 35 U.S.C. 103 as being unpatentable over Han in view of Byun US 20230152301 A1; hereinafter “Byun”; priority filed on 12/6/2021).
Regarding claim 9, Han teaches the microfluidic device according to claim 1, with the microchannel.
Han does not teach wherein the microchannel includes a helical partial channel, and in the helical partial channel, large size particles congregate inward in a helix, and small size particles congregate outward in the helix by the action of the flow in the channel cross-section.
However, Byun teaches an analogous art of a spiral microfluidic device (Byun; Abstract) comprising a microchannel (Byun; para [27]; a two-loop spiral microchannel (130) having a rectangular cross-section in which the radially inner portion and the outer portion are uniform in height and the width of the upper part is equal to the width of the base) includes a helical partial channel, and in the helical partial channel (Byun; para [28]; FIG. 1(b) also describes optical images of single and multi-helical biochips for high-throughput isolation of CTCs from lysed blood and possible downstream techniques for functional characterization of isolated CTCs using helical biochips), large size particles congregate inward in a helix, and small size particles congregate outward in the helix by the action of the flow in the channel cross-section (Byun; para [34]; As a result, in the channel outlet region, larger particles are concentrated and aligned near the inner wall, while smaller particles occupying a lateral position near the outer wall can be properly achieved). It would have been obvious to one of having ordinary skill in the art before the effective filing date of the claimed microchannel to be in the shape of the helical partial channel, since it has been held that a mere change in shape of an element is generally recognized as being within the level of ordinary skill in the art when the change in shape is not significant to the function of the combination, MPEP 2144.04 (IV)(B). Further, one would have been motivated to select the shape of helical for the purpose of CTC separation.
Regarding claim 10, modified Han teaches the microfluidic device according to claim 9, wherein the microchannel separates the particles such that the large size particles are brought closer to a channel wall by the action of the lift force (Han; para [30, 65, 75, 94]; At certain flow rates, the larger particle can focus along the inner wall influenced by both Dean flow and inertial lift, while the smaller particles tend to get trapped in the vortex center at the outer side).
Conclusion
Any inquiry concerning this communication or earlier communications from the examiner should be directed to Austin Q Le whose telephone number is (571)272-7556. The examiner can normally be reached Monday - Friday 9am - 5pm.
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/A.Q.L./Examiner, Art Unit 1796
/MATTHEW D KRCHA/Primary Examiner, Art Unit 1796
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