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 Claims
Applicant’s amendments to the claims, filed 03 October 2025, have been entered. Applicant’s remarks in reconsideration of the application, filed 03 October 2025, are acknowledged.
Claims 1-25 are in status “cancelled.” Claims 26, 39, 40, and 42 are in status “Currently amended.” Claims 27 – 38, 41, and 43 – 45 are in status “Original” or “Previously Presented.”
Response to Arguments
Applicant's arguments filed 03 October 2025 with regards to the rejection under 35 U.S.C. 103 have been fully considered but they are not persuasive.
Applicant’s amendments to claim 26 are aimed at narrowing the scope of the claim by further specifying the number of microfluidic channels in the device, the connections of channels to the inlets and outlets, and the position of the inlets and outlets on the device. Ultimately, however, these are changes that would be obvious to one of ordinary skill in the art.
With regards to applicant’s arguments that the amended claims specify a single microchannel per layer, MPEP 2144(II)(A) teaches that “omission of an element and its function is obvious of the function of the element is not desired.” Of most relevance is In re Larson, 340 F.2d 965, 144 USPQ 347 (CCPA 1965). If the additional fluid capacity of the multiple fluid channels taught by Borenstein is not desired, it would be obvious to omit them. Moreover, Borenstein itself allows for variations in the number of channels and connections; [0030] of Borenstein teaches that “each layer defines at least one flow chamber […] a “flow chamber” refers to any conduit for carrying fluid across a layer in the device. Flow chambers can generally be classified as […] flow channels….” This clearly encompasses an embodiment with one flow channel, even if the figures display an embodiment with multiple channels.
With regard to applicant’s arguments that the fluid channels first intersect with the primary channel 771 before connecting to inlet and outlet 772, this argument is not persuasive given the broadest reasonable interpretation of the claim language. The fluid channel is connected to the inlet and outlet through the primary channel, but the fluidic connection is still present and functional. The existence of an intermediary does not eliminate that connection. Moreover, the language of claim 26 is open (ie, “comprising”), and so does not exclude any other elements taught by the prior art.
With regards to applicant’s arguments that Borenstein does not explicitly disclose wherein the inlets and outlets are position on the top surface of the manifold, this is mere rearrangement of parts. According to MPEP 2144(VI)(C), rearrangement of parts within a device is not sufficient to distinguish a claimed invention from the prior art in cases where the rearrangement does not modify operation of the device or where the rearrangement is an obvious matter of design choice; see In re Japikse, 181 F.2d 1019, 86 USPQ 70 (CCPA 1950) and In re Kuhle, 526 F.2d 553, 188 USPQ 7 (CCPA 1975). Additionally, Hosic et al teaches inlets at the top of layers (see for instance, Figure 3).
In all the above examples, the specification of the instant application does not explicitly disclose any unexpected results occurring because of the amended limitations. A submission by the applicant of unexpected results or non-obvious motivations for the changes in structures would better support a case of patentability. In the interest of furthering prosecution, additional prior art references have been added in the conclusion section, with a brief description of how they may be considered in light of the amended claims.
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 26, 30-33, and 43-45 are rejected under 35 U.S.C. 103 as being unpatentable over Borenstein et al (US 20170349912 A1), cited on the IDS submitted 31 December 2021, in view of Hosic et al (US 20190083979 A1) and further in view of Yamakawa et al (US 20050148064 A1).
With regards to claim 26, Borenstein et al teaches;
The claimed “A microfluidic platform” has been read on the taught (Figure 1A, cell transduction stack 100; [0081] details the size of fluid channels 752, which are consistent with a microfluidic system);
The claimed “a top layer comprising a top inlet and a top outlet,” and “a horizontally aligned microchannel having two ends, wherein one end of the microchannel is connected to the top inlet and the other end of the microchannel is connected to the top outlet” has been read on the taught (Figure 7A, first substrate 704 with integrated manifold 716; Figure 7C shows ports 772 on manifold 716 which read on the inlet and outlet; [0083], “The integrated manifolds 716 are formed […] with a port 772 […] to which the fluidics shown in FIG. 7A can couple.”; [0078], “…the flow chambers in the first, second, and third substrates 704, 706, and 708 are formed from multiple parallel fluid channels 752…”; the flow chamber reads on a horizontally aligned microchannel.);
The claimed a “center layer,” a center layer “comprising a center inlet and a center outlet” and a layer comprising a “horizontally aligned microchannel having two ends, wherein one end of the microchannel is connected to the center inlet and the other end of the microchannel is connected to the center outlet” has been read on the taught (Figure 7A, second substrate 706 with integrated manifold 716; Figure 7C shows ports 772 which read on the inlet and outlet; [0083], “The integrated manifolds 716 are formed […] with a port 772 […] to which the fluidics shown in FIG. 7A can couple.”; [0078], “…the flow chambers in the first, second, and third substrates 704, 706, and 708 are formed from multiple parallel fluid channels 752…”; the flow chamber reads on a horizontally aligned microchannel.);
The claimed “a bottom layer comprising a bottom inlet and a bottom outlet” and a “horizontally aligned microchannel having two ends, wherein one end of the microchannel is connected to the bottom inlet and the other end of the microchannel is connected to the bottom outlet” has been read on the taught (Figure 7A, third substrate 708 with integrated manifold 716; Figure 7C shows ports 772 on manifold 716 which read on the inlet and outlet; [0083], “The integrated manifolds 716 are formed […] with a port 772 […] to which the fluidics shown in FIG. 7A can couple.”; [0078], “…the flow chambers in the first, second, and third substrates 704, 706, and 708 are formed from multiple parallel fluid channels 752…”; the flow chamber reads on a horizontally aligned microchannel.);
With regards to the limitation that each layer comprises “a single horizontally aligned microchannel,” Borenstein et al does not teach away from this embodiment. [0030] recites that “each layer defines at least one flow chamber […] a “flow chamber” refers to any conduit for carrying fluid across a layer in the device. Flow chambers can generally be classified as […] flow channels….” At least one reads on one. MPEP 2144(II)(A) teaches that “omission of an element and its function is obvious of the function of the element is not desired”; see In re Larson, 340 F.2d 965, 144 USPQ 347 (CCPA 1965). As the specification of the instant application does not disclose any unexpected result due to the number of microchannels, the limitations of “a single horizontally aligned microchannel” are not sufficient to distinguish the claimed invention over the prior art.
With regards to the limitation that each inlet and outlet is “located on the top surface” of its respective layer, this is mere rearrangement of parts. According to MPEP 2144(VI)(C), rearrangement of parts within a device is not sufficient to distinguish a claimed invention from the prior art in cases where the rearrangement does not modify operation of the device or where the rearrangement is an obvious matter of design choice; see In re Japikse, 181 F.2d 1019, 86 USPQ 70 (CCPA 1950) and In re Kuhle, 526 F.2d 553, 188 USPQ 7 (CCPA 1975). As the specification of the instant application does not disclose any unexpected results due to the position of the inlets and outlets, these limitations are not sufficient to distinguish the claimed invention over the prior art.
Borenstein et al additionally teaches;
The claimed “a first porous membrane between the top layer and the center layer” has been read on the taught (Figure 7A, first membrane 710; [0076], "The first substrate 704 is separated from the second substrate 706 by a first membrane 710.");
The claimed “a second porous membrane between the bottom layer and the center layer” has been read on the taught (Figure 7A, second membrane 712; [0076], "The second substrate 706 is separated from the third substrate 708 by a second membrane 712.");
However, Borenstein et al does not explicitly disclose the microfluidic platform comprising a plurality of center layers with each center layer of the plurality of center layers comprising a center inlet and a center outlet, a plurality of center porous membranes between each center layer of the plurality of center layers, a first electrode disposed on at least one of the top layer and the bottom layer, and a second electrode disposed on at least one of the top layer and bottom layer.
In the analogous art of microfluidic devices containing membranes, Hosic et al teaches the following:
The claimed “a top layer” has been read on (Figure 2B, first layer 230a; [0050], "The view depicts: […] a first layer 230a…”);
The claimed “a bottom layer” has been read on (Figure 2B, fifth layer 230e; [0050], “The view depicts: […] a fifth layer 230e…”);
The claimed “a plurality of center layers” has been read on the taught (Figure 2B, layers 230b-d; [0050], “The view depicts: […] a second layer 230b, […] a third layer 230c, […] a fourth layer 230d…”);
The claimed “each center layer of the plurality of center layers comprising a center inlet and a center outlet, each located on the top surface of each center layer” has been read on the taught (Figure 2C, plenums 225a-b; paragraph 0052, “The plenums 225a-b […] are configured to be in fluidic communication with the cavity in the fluidic device… The fluidic device 200 […] enables fluids […] to enter through the plenums, which can also be referred to as inlet plenums, travel through plenums to the member defining a cavity, with which plenums are in fluidic communication, pass through the cavity and into respective output plenums.”; See figure 3 which depicts inlets and outlets communicating through the tops of the various layers.);
The claimed “a plurality of center porous membranes between each center layer of the plurality of center layers” has been read on the taught (Figure 2B, porous membrane 255; Figure 2B shows membranes 255 positioned between layers 230b and 230c, and between layers 230c and 230d; [0050], “The view depicts: […] a fourth layer 230d, featuring […] a first and second member 210a-b, the first member 210a being directly coupled to the porous membrane 255 of the third layer 230c; […] a porous membrane 255 situated in between the second layer 230b and third layer 230c…”).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to combine the microfluidic system as taught by Borenstein et al with the plurality of center layers and center porous membranes as taught by Hosic et al, in order to allow for molecular traversal through the membranes which promotes physical interactions between different layers (Hosic et al, paragraph 0013, “In some embodiments, separate flow path layers may be configured to interact with one another through integration of a porous membrane, which is configured to promote physical interaction between the different layers, through, for example, molecular traversal through the membrane.”).
The system of Borenstein et al in view of Hosic et al fails to teach a first electrode disposed on at least one of the top layer and the bottom layer, and a second electrode disposed on at least one of the top layer and the bottom layer.
In the analogous art of microfluidic devices for separating molecules, Yamakawa et al teaches the following:
The claimed “a top layer” has been read on the taught (Figure 2a, upper substrate 120; [0028], “The substrate 102 includes an upper substrate 120…”);
The claimed “a bottom layer” has been read on the taught (Figure 2a, lower substrate 122; Paragraph 0028, “The substrate 102 includes […] a lower substrate 122…”);
The claimed “a first electrode disposed on at least one of the top layer and the bottom layer” has been read on the taught (Figure 3e, electrode 162; Figure 3e shows an electrode 162 positioned on the same side as channel 104. Per paragraph 0028, “The upper microfluidic channel 104 is formed in the upper substrate member 120…”);
The claimed “a second electrode disposed on at least one of the top layer and the bottom layer” has been read on the taught (Figure 3e, electrode 162; Figure 3e shows an electrode 162 positioned on the same side as channel 106. Per paragraph 0028, “…the lower microfluidic channel 106 is formed in the lower substrate 122.”).
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 microfluidic system of Borenstein et al in view of Hosic et al with the electrodes as taught by Yamakawa et al, in order to create an electric field for electrophoretic and dielectrophoretic trapping and/or control within the system (Yamakawa et al, paragraph 0035, “An electric field is used to create electrophoretic and dielectrophoretic trapping and/or control…”).
With regards to 30-33 and 43-45, the platform of claim 26 is obvious over Borenstein et al in view of Hosic et al and further in view of Yamakawa et al.
Borenstein et al in view of Hosic et al further in view of Yamakawa et al teaches each additional element of these claims, as outlined in the final rejection filed 03 July 2025, beginning on page 8.
Claims 27, 34-37 and 39 are rejected under 35 U.S.C. 103 as being unpatentable over Borenstein et al (US 20170349912 A1) in view of Hosic et al (US 20190083979 A1) and further in view of Yamakawa et al (US 20050148064 A1) as applied to claim 26 above, and further in view of Ayyub et al (US 20160231310 A1).
With regards to claim 27, 34-37 and 39, the platform of claim 26 is obvious over Borenstein et al in view of Hosic et al, and further in view of Yamakawa et al. These combined references do not explicitly disclose certain limitations of the aforementioned claims; however, these limitations are taught by Ayyub et al and the combination would have been obvious to one of ordinary skill in the art, as outlined in the final rejection filed 03 July 2025, beginning on page 12.
Claim 28 is rejected under 35 U.S.C. 103 as being unpatentable over Borenstein et al (US 20170349912 A1) in view of Hosic et al (US 20190083979 A1) in view of Yamakawa et al (US 20050148064 A1) in view of Ayyub et al (US 20160231310 A1) as applied to claim 27 above, and further in view of Susanto and Ubricht (Susanto H, Ulbricht M. Photografted Thin Polymer Hydrogel Layers on PES Ultrafiltration Membranes: Characterization, Stability, and Influence on Separation Performance. Langmuir. 2007; 23: 7818-7830).
With regards to claim 28, the platform of claim 27 is obvious over Borenstein et al in view of Hosic et al in view of Yamakawa et al and further in view of Ayyub et al. These combined references do not explicitly disclose certain limitations of the aforementioned claim. However, these limitations are taught by Susanto and Ubricht, and the combination would have been obvious to one of ordinary skill in the art, as outlined in the final rejection filed 03 July 2025, beginning on page 15.
Claim 29 is rejected under 35 U.S.C. 103 as being unpatentable over Borenstein et al (US 20170349912 A1) in view of Hosic et al (US 20190083979 A1) in view of Yamakawa et al (US 20050148064 A1) in view of Ayyub et al (US 20160231310 A1) as applied to claim 27 above, and further in view of Mitsuhashi (US 20180340945 A1).
With regards to claim 29, the platform of claim 27 is obvious over Borenstein et al in view of Hosic et al in view of Yamakawa et al and further in view of Ayyub et al. These combined references do not explicitly disclose certain limitations of the aforementioned claim. However, these limitations are taught by Mitsuhashi, and the combination would have been obvious to one of ordinary skill in the art, as outlined in the final rejection filed 03 July 2025, beginning on page 17.
Claim 38 is rejected under 35 U.S.C. 103 as being unpatentable over Borenstein et al in view of Hosic et al in view of Yamakawa et al in view of Ayyub et al as applied to claim 34 above, and further in view of Poon et al (Poon YF, Cao Y, Zhu Y, Judeh ZMA, Chan-Park MB. Addition of β-Malic Acid-Containing Poly(ethylene glycol) Dimethacrylate To Form Biodegradable and Biocompatible Hydrogels. Biomacromolecules. 2009; 10(8): 2043-2052).
With regards to claim 38, the platform of claim 27 is obvious over Borenstein et al in view of Hosic et al in view of Yamakawa et al and further in view of Ayyub et al. These combined references do not explicitly disclose certain limitations of the aforementioned claim. However, these limitations are taught by Poon et al, and the combination would have been obvious to one of ordinary skill in the art, as outlined in the final rejection filed 03 July 2025, beginning on page 18.
Claims 40-42 are rejected under 35 U.S.C. 103 as being unpatentable over Borenstein et al (US 20170349912 A1) in view of Hosic et al (US 20190083979 A1) in view of Yamakawa et al (US 20050148064 A1) as applied to claim 26 above, and further in view of Maksin et al (Maksin, D, Nastasović A, Milutinović-Nikolić A, Suručić L, Sandić Z, Hercigonja R, Onjia A. Equilibrium and kinetics study on hexavalent chromium adsorption onto diethylene triamine grafted glycidyl methacrylate based copolymers. Journal of Hazardous Materials. 2012; 209-210: 99-110) and Susanto and Ulbricht (Susanto H, Ulbricht M. Photografted Thin Polymer Hydrogel Layers on PES Ultrafiltration Membranes: Characterization, Stability, and Influence on Separation Performance. Langmuir. 2007; 23: 7818-7830).
With regards to claims 40 – 42, the platform of claim 26 is obvious over Borenstein et al in view of Hosic et al, and further in view of Yamakawa et al. These combined references do not explicitly disclose certain limitations of the aforementioned claims; however, these limitations are taught by Maksin et al and the combination would have been obvious to one of ordinary skill in the art, as outlined in the final rejection filed 03 July 2025, beginning on page 18.
Conclusion
The prior art made of record and not relied upon is considered pertinent to applicant's disclosure.
Culkin (US 5080770 A) teaches an apparatus for separating particles using an electric field (Abstract) with membranes interposed between channel layers (Figure 2), and with various configurations for directing fluid flow through channel layers (Column 7, line 55).
Karp et al (US 20030198130 A1) teaches a stacked microfluidic device with multiple inlet channels (Abstract) and which allows for a membrane to be interspersed between the layers (see [0038]).
Ichiki et al (US 20170234832 A1) teaches an electrophoresis device for use in separating extracellular vesicles, and may provide methods and motivations regarding separation of exosomes (Abstract).
Any inquiry concerning this communication or earlier communications from the examiner should be directed to ALISON CLAIRE GERHARD whose telephone number is (571)270-0945. The examiner can normally be reached M-F, 9:00 - 5:30pm EST.
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/ALISON CLAIRE GERHARD/ Examiner, Art Unit 1797 /LYLE ALEXANDER/ Supervisory Patent Examiner, Art Unit 1797