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 with traverse of Group 2, claims 37, 39, and 44-55 in the reply filed on 10/03/2025 is acknowledged. The traversal is on the ground(s) that there would be no search burden between Groups 3 and 4. This is not found persuasive because the restriction is being treated under 35 U.S.C. 371 (unity of invention analysis) and not 35 U.S.C. 111(a) (independent and distinct analysis) (see MPEP 823). The groups of inventions do not relate to a single general inventive concept under PCT Rule 13.1 because, under PCT Rule 13.2, they lack the same or corresponding special technical features since the shared special technical feature do not make a contribution over the prior art in view of Norikane et al. (EP 1810746 B1; cited in the IDS filed 11/04/2022) as discussed in Requirement for Restriction filed 08/04/2025 (see pages 5-7). Additionally, as discussed below in the rejection of claim 37, the features of claim 37 are not special in view of Harvengt et al. (WO 2018219521 A1; cited in the IDS filed 08/27/2024) in view of Fu et al. (CN 1542429 A; see machine translation).
The requirement is still deemed proper and is therefore made FINAL.
Claims 24, 38, and 40-43 are withdrawn from further consideration pursuant to 37 CFR 1.142(b), as being drawn to a nonelected inventions, there being no allowable generic or linking claim. Applicant timely traversed the restriction (election) requirement in the reply filed on 10/03/2025.
Applicant’s election without traverse of the species of a method of manufacturing a liposomal adjuvant using a microfluidic device, i.e. claims 37, 39, and 44-54, in the reply filed on 10/03/2025 is acknowledged.
Claim 55 is withdrawn from further consideration pursuant to 37 CFR 1.142(b) as being drawn to a nonelected species, there being no allowable generic or linking claim. Election was made without traverse in the reply filed on 10/03/2025.
Drawings
Figure 2 should be designated by a legend such as --Prior Art-- because only that which is old is illustrated (specification, page 3, lines 1-2). See MPEP § 608.02(g). Corrected drawings in compliance with 37 CFR 1.121(d) are required in reply to the Office action to avoid abandonment of the application. The replacement sheet(s) should be labeled “Replacement Sheet” in the page header (as per 37 CFR 1.84(c)) so as not to obstruct any portion of the drawing figures. If the changes are not accepted by the examiner, the applicant will be notified and informed of any required corrective action in the next Office action. The objection to the drawings will not be held in abeyance.
Claim Objections
Claim 46 is objected to because of the following informalities: It is suggested to recite “the one first inlet channels” in lines 1-2 as “the one first inlet channel”. Appropriate correction is required.
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.
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 37, 39, and 44-52 are rejected under 35 U.S.C. 103 as being unpatentable over Harvengt et al. (WO 2018219521 A1; cited in the IDS filed 08/27/2024) in view of Fu et al. (CN 1542429 A; see machine translation).
Regarding claim 37, Harvengt teaches a method of manufacturing a liposomal adjuvant using a microfluidic device (page 5, lines 35-36; Fig. 1),
the microfluidic mixing device (Fig. 1; pages 7-10) comprising:
(i) a mixing chamber (Fig. 1; page 7, “mixing chamber”);
(ii) one first inlet channel (Fig. 1 and page 8, second paragraph, teaches at least one inlet for delivery of a first solution; page 9, fourth paragraph), which is into the mixing chamber (page 8, second paragraph);
(iii) two second inlet channels (Fig. 1 and page 8, third paragraph, teaches two inlets for delivery of a second solution; page 9, fourth paragraph), which are into the mixing chamber (page 8, third paragraph);
(iv) an outlet (Fig. 1 and page 8, last paragraph; page 9, fourth paragraph), which is from the mixing chamber (Fig. 1 and page 8, last paragraph);
wherein:
the one first inlet channel and two second inlet channels are disposed substantially symmetrically at a proximal end of the mixing chamber (Fig. 1 and page 9, fourth paragraph) and the outlet is at a distal end of the mixing chamber (Fig. 1 and page 9, fourth paragraph);
the method comprising:
(a) mixing in the device mixing chamber a first solution and a second solution, thereby obtaining a mixed material comprising the liposomal adjuvant (page 6, lines 1-2, teaches mixing in the device a first solution comprising a solvent, phosphatidylcholine lipid and a sterol, and a second solution comprising water and the saponin, therefore comprises a mixed material comprising a liposomal adjuvant; page 15 teaches mixing of the first and second solutions in the mixing chamber; page 16 teaches upon mixing of the first and second solutions, liposomes will form), the first solution being delivered into the mixing chamber by the one first inlet channel (page 8, second paragraph; page 9, fourth paragraph) and comprising a solvent and a lipid (page 6, lines 1-2, “solvent, phosphatidylcholine lipid and a sterol”), the second solution comprising water (page 6, lines 1-2) and being delivered into the mixing chamber by the two second inlet channels (page 8, third paragraph; page 9, fourth paragraph), the mixed material exiting the mixing chamber by the outlet (page 8, last paragraph teaches an outlet for recover of the mixed material, therefore mixed materials exits the mixing chamber by the outlet); and
(b) removing the solvent from the mixed material (page 6, line 3).
While Harvengt teaches the desire to facilitate adequate mixing (page 8, lines 13-14), Harvengt fails to teach: the mixing chamber comprising a baffle.
Fu teaches a microfluidic chemical analysis system device comprising a cross-flow-guiding micro static mixer (paragraph [0002]; Figs. 1-5). Fu teaches purpose of mixing is to reduce heterogeneity, for example for dilution, or to enhance the rate of chemical reactions, so it is very important to achieve fast and efficient mixing (paragraph [0004]). Fu teaches the device comprises a mixing chamber (Figs. 1-3, elements 6 and 7) and the mixing chamber includes baffles (Figs. 1-3, guide blocks 4, 4’, 5, 5’). Fu teaches the invention has the following beneficial effects: by arranging alternating guide blocks in the pipeline, shear flow and extension flow can be generated in the flow field, the interface area between different fluids is increased, the molecular diffusion effect is enhanced, and ultimately uniform mixing at the molecular level is achieved (paragraph [0013]).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have modified the mixing chamber of Harvengt to incorporate the teachings of microfluidic devices comprising a mixing chamber with baffles of Fu (Figs. 1-3; paragraph [0013]) to provide: the mixing chamber comprising a baffle. Doing so would have a reasonable expectation of successfully improving mixing as taught by Fu (paragraph [0013]).
Regarding claim 39, Harvengt further teaches the method of claim 37 further comprising: (c) mixing the liposomal adjuvant with an immunogen, or a polynucleotide encoding the immunogen (page 24, lines 1-3).
Regarding claim 44, Harvengt further teaches wherein the first inlet channel is from 0.1 mm to 0.7 mm wide (page 32, lines 27-28, teaches the inlets are 0.2 mm wide).
Regarding claim 45, Harvengt further teaches wherein the two second inlet channels fluid are each 0.025 mm to 0.3 mm wide (page 32, lines 27-28, teaches the inlets are 0.2 mm wide).
Regarding claim 46, Harvengt further teaches wherein each of the directions of flow from the one first inlet channels and the two second inlet channels into the mixing chamber are substantially parallel to the general direction of flow in the mixing chamber (page 8, lines 32-35).
Regarding claim 47, Harvengt further teaches wherein the mixing chamber has a length from 15 mm to 100 mm (page 9, lines 8-9 teaches the mixing chamber has a length of 1.5-5 cm, i.e. 15-50mm).
Regarding claim 48, Harvengt further teaches wherein the mixing chamber has a maximum width of from 0.8 mm to 2.2 mm (page 39, line 26 teaches the mixing chamber width is 2000um, i.e. 2mm).
Regarding claim 49, Harvengt further teaches wherein the mixing chamber has a minimum width of from 0.8 mm to 2.2 mm (page 39, line 26 teaches the mixing chamber width is 2000um, i.e. 2mm).
Regarding claim 50, Harvengt further teaches wherein the mixing chamber has a depth of from 0.1 mm to 2 mm (page 39, line 26 teaches the mixing chamber height is 400um, i.e. 0.4 mm).
Regarding claim 51, modified Harvengt fails to teach wherein the mixing chamber comprises at least two of the baffles; and the at least one of the baffles is present on each side of the mixing chamber between the proximal end and distal end of the mixing chamber.
Fu teaches a microfluidic chemical analysis system device comprising a cross-flow-guiding micro static mixer (paragraph [0002]; Figs. 1-5). Fu teaches purpose of mixing is to reduce heterogeneity, for example for dilution, or to enhance the rate of chemical reactions, so it is very important to achieve fast and efficient mixing (paragraph [0004]). Fu teaches the device comprises a mixing chamber (Figs. 1-3, elements 6 and 7) and the mixing chamber includes at least two baffles present on each side of the mixing chamber between two ends of the mixing chamber (Figs. 1-3, guide blocks 4, 4’, 5, 5’). Fu teaches the invention has the following beneficial effects: by arranging alternating guide blocks in the pipeline, shear flow and extension flow can be generated in the flow field, the interface area between different fluids is increased, the molecular diffusion effect is enhanced, and ultimately uniform mixing at the molecular level is achieved (paragraph [0013]).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have modified the mixing chamber of modified Harvengt to incorporate the teachings of microfluidic devices comprising a mixing chamber with baffles of Fu (Figs. 1-3; paragraph [0013]) to provide: wherein the mixing chamber comprises at least two of the baffles; and the at least one of the baffles is present on each side of the mixing chamber between the proximal end and distal end of the mixing chamber. Doing so would have a reasonable expectation of successfully improving mixing as taught by Fu (paragraph [0013]).
Regarding claim 52, modified Harvengt fails to teach wherein the mixing chamber comprises comprising 4 to 100 of the baffles.
Fu teaches a microfluidic chemical analysis system device comprising a cross-flow-guiding micro static mixer (paragraph [0002]; Figs. 1-5). Fu teaches purpose of mixing is to reduce heterogeneity, for example for dilution, or to enhance the rate of chemical reactions, so it is very important to achieve fast and efficient mixing (paragraph [0004]). Fu teaches the device comprises a mixing chamber (Figs. 1-3, elements 6 and 7) and the mixing chamber includes at least two baffles present on each side of the mixing chamber between two ends of the mixing chamber (Figs. 1-3, guide blocks 4, 4’, 5, 5’). Fu teaches the invention has the following beneficial effects: by arranging alternating guide blocks in the pipeline, shear flow and extension flow can be generated in the flow field, the interface area between different fluids is increased, the molecular diffusion effect is enhanced, and ultimately uniform mixing at the molecular level is achieved (paragraph [0013]). Fu teaches at least 4 baffles (Figs. 1-3).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have modified the mixing chamber of modified Harvengt to incorporate the teachings of microfluidic devices comprising a mixing chamber with at least 4 baffles of Fu (Figs. 1-3; paragraph [0013]) to provide: wherein the mixing chamber comprises comprising 4 to 100 of the baffles. Doing so would have a reasonable expectation of successfully improving mixing as taught by Fu (paragraph [0013]).
Claim 53 is rejected under 35 U.S.C. 103 as being unpatentable over Harvengt in view of Fu as applied to claim 37 above, and further in view of He et al. (CN105771765A; see machine translation).
Regarding claim 53, modified Harvengt fails to teach: wherein each baffle is 0.1 mm to 1 mm wide.
He teaches a microfluidic system comprising a micro-mixer (paragraph [0002]; Fig. 3), wherein micromixers are known to include passive micromixers that mainly use microchannels with complex geometric structures (such as adding baffles and opening grooves in microchannels) to form chaotic convection to increase the convection intensity of the fluid, thereby increasing the contact area of fluid mixing and improving the mixing efficiency (paragraph [0005]). He teaches a microfluidic system (Figs. 3-4) comprising a mixing chamber (3) with baffles (5). He teaches a channel width of 0.1-0.2mm (paragraph [0023) and the width L4 of the baffle is equal to the width of the channel, i.e. 0.1-0.2mm (paragraph [0025]).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have modified each baffle of modified Harvengt to incorporate the teachings of microfluidic systems with baffles having a width of 0.1-0.2mm of He (paragraphs [0023],[0025]) to provide wherein each baffle is 0.1 mm to 1 mm wide. Doing so would have a reasonable expectation of successfully providing for improved mixing efficiency as discussed by He (paragraph [0005]).
Additionally, since He teaches a width of a baffle of 0.1-0.2mm (paragraphs [0023],[0025]), which overlaps the claimed range of 0.1-1mm, it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have modified each baffle of modified Harvengt to incorporate the teachings of baffles having a width of 0.1-0.2mm of He (paragraphs [0023],[0025]) to provide: wherein each baffle is 0.1 mm to 1 mm wide. I.e., it would have been prima facia obvious to have selected the overlapping portion of the ranges from the taught range of He (paragraphs [0023],[0025]) (In re Wertheim, 541 F.2d 257, 191 USPQ 90 (CCPA 1976); see MPEP 2144.05 (I)).
Claim 54 is rejected under 35 U.S.C. 103 as being unpatentable over Harvengt in view of Fu as applied to claim 37 above, and further in view of Chen et al. (Chen et al., “Numerical and experimental investigation on micromixers with serpentine microchannels”, International Journal of Heat and Mass Transfer 98 (2016) 131–140) and Norikane et al. (EP 1810746 A1; cited in the IDS filed 11/04/2022).
Regarding claim 54, Harvengt further teaches wherein:
(i) the mixing chamber: (A) has 25 mm in length (page 9, line 9 and page 32, line 25 teach the length of the mixing chamber is 2.5 cm), (B) has a rectangular cross-section perpendicular to the length (page 9, lines 10-11), and (C) comprises a first side, a second side, a top wall, a bottom wall (page 9, lines 10-16 teaches the mixing chamber has rectangular cross-section, therefore has first and second sides and top and bottom walls), wherein:
the top wall and bottom wall are: parallel to each other, run the length of the mixing chamber (Fig. 1 and page 9, lines 10-16 teaches the mixing chamber has rectangular cross-section, therefore the top and bottom walls are parallel and run the length of the chamber) and spaced to provide the mixing chamber with a depth (Fig. 1 and page 9, lines 10-16 teaches the mixing chamber has rectangular cross-section, which has a depth);
the first side and second side are: parallel to each other, run the length of the mixing chamber (Fig. 1 and page 9, lines 10-16 teaches the mixing chamber has rectangular cross-section, therefore the first and second sides are parallel and run the length of the chamber);
(ii) the one first inlet channel: (A) is located about centrally at the proximal end of the mixing chamber (Fig. 1; page 32, lines 26-27), (B) has a rectangular cross-section (page 8, lines 15-16 and 29-31);
(iii) the two second inlet channels: (A) are identical in shape (page 8, lines 26-28), (B) are located at each of the parallel sides along the length on the proximal end of the mixing chamber (Fig. 1 and page 8, third paragraph and lines 32-35, teaches two inlets located at parallel sides along the length of the mixing chamber for delivery of a second solution; page 9, fourth paragraph), (C) each have rectangular cross-section (8, lines 15-16 and 29-31); and
each of the directions of flow from the one first inlet channels and the two second inlet channels into the mixing chamber are substantially parallel to the general direction of flow in the mixing chamber (page 8, lines 32-35).
Modified Harvengt fails to teach:
the mixing chamber comprising 12 of the baffles;
the top wall and the bottom wall are spaced to provide the mixing chamber with a depth of 0.5 mm; the first side and second side are spaced 1.6 mm apart;
six of the 12 baffles are located on the first side, six of the 12 baffles are located on the second side, the first baffle is located on the first side 4.4 mm from the proximal end of the mixing chamber, the second baffle is located on the second side 6.132 mm from the proximal end of the mixing chamber, each baffle on the first side is separated from the next baffle on the first side by 3.464 mm, each baffle on the second side is separated from the next baffle on the second side by 3.464 mm, each baffle is trapezium in shape and has a length of from 0.25 mm to 0.55 mm and a width of 0.5 mm;
(ii) the one first inlet channel: (C) has a width of 0.27 mm, (E) and has a depth of 0.5 mm;
(iii) the two second inlet channels (D) each have a width of 0.1 mm, and (E) each have a depth of 0.5 mm.
Harvengt teaches the mixing chamber having a cross-sectional area of 0.2-3.2 mm2 (e.g. 0.6-1.0 mm2), a long side, i.e. spacing between sides, of 1.4-3.2 mm (e.g. 1.6-2.4 mm), a short side, i.e. depth, of 0.1-1.2 mm (e.g. 0.32-0.48 mm) (page 9, lines 10-12).
Since Harvengt teaches a depth of 0.1-1.2mm and spacing between sides of 1.4-3.2mm (page 9, lines 10-12), which overlaps the claimed range of a depth of 0.5 mm and the first side and second side are spaced 1.6 mm apart, it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have modified the dimensions of the mixing chamber of modified Harvengt to incorporate the teachings of dimension ranges of the mixing chamber of Harvengt (page 9, lines 10-12) to provide: the top wall and the bottom wall are spaced to provide the mixing chamber with a depth of 0.5 mm; the first side and second side are spaced 1.6 mm apart. I.e., it would have been prima facia obvious to have selected the overlapping portion of the ranges from the taught range Harvengt (page 9, lines 10-12) (In re Wertheim, 541 F.2d 257, 191 USPQ 90 (CCPA 1976); see MPEP 2144.05 (I)).
Modified Harvengt fails to teach:
the mixing chamber comprising 12 of the baffles;
six of the 12 baffles are located on the first side, six of the 12 baffles are located on the second side, the first baffle is located on the first side 4.4 mm from the proximal end of the mixing chamber, the second baffle is located on the second side 6.132 mm from the proximal end of the mixing chamber, each baffle on the first side is separated from the next baffle on the first side by 3.464 mm, each baffle on the second side is separated from the next baffle on the second side by 3.464 mm, each baffle is trapezium in shape and has a length of from 0.25 mm to 0.55 mm and a width of 0.5 mm;
(ii) the one first inlet channel: (C) has a width of 0.27 mm, (E) and has a depth of 0.5 mm;
(iii) the two second inlet channels: (D) each have a width of 0.1 mm, and (E) each have a depth of 0.5 mm.
Harvengt teaches optimal operating conditions will depend on the precise configuration of the device and the desired characteristics of the product (page 15, lines 6-7). Harvengt teaches suitable ratio of flow rates between the first and second solutions (page 15, lines 8-24). Harvengt teaches the cross-sectional area of inlets is 0.02-0.32 mm2, such as 0.04-0.16 mm2 (page 8, lines 20-22). Harvengt teaches an inlet with a width of 0.2 mm and depth of 0.4 mm (page 8, lines 29-31).
MPEP 2144.05 (II)(B) holds that a particular parameter that is recognized as a result effective variable (“a variable that achieves a recognized result”) would be one, but not the only motivation for a person of ordinary skill in the art to experiment to reach another workable product or process. In the design and fabrication of microfluidic devices, the selection of optimal experimental conditions including structural geometry and dimensions affects fluidic transport parameters such as pressure and flow rate which in turn affect mixing characteristics of desired fluids in a mixing chamber (Harvengt, page 8, lines 29-31, discusses ranges of ratios of flow rates between the first and second solutions, which relate to the first and second inlet channels). Thus, the width and depths of the first and second inlet channels are a result effective variables.
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have modified the one first inlet channel and the two second inlet channels of modified Harvengt to incorporate the teachings of ranges of cross-sectional areas of inlets, suitable ratios of flow rates between the first and second solutions, and optimizing configuration of the device of Harvengt (page 8, lines 20-22; page 15, lines 6-24) to provide: (ii) the one first inlet channel: (C) has a width of 0.27 mm, (E) and has a depth of 0.5 mm; (iii) the two second inlet channels: (D) each have a width of 0.1 mm, and (E) each have a depth of 0.5 mm through routine experimentation (MPEP 2144.05 (II)). I.e., it would have been obvious to design and fabricate the inlet channels to modify the result-effective variables, i.e. width and depth, and arrive at the claimed dimensions through routine optimization of workable dimensions for microfluidic channels to optimize the flow rates for each inlet and the ratio of flow rates between the first and second inlet channels.
Modified Harvengt fails to teach:
the mixing chamber comprising 12 of the baffles;
six of the 12 baffles are located on the first side, six of the 12 baffles are located on the second side, the first baffle is located on the first side 4.4 mm from the proximal end of the mixing chamber, the second baffle is located on the second side 6.132 mm from the proximal end of the mixing chamber, each baffle on the first side is separated from the next baffle on the first side by 3.464 mm, each baffle on the second side is separated from the next baffle on the second side by 3.464 mm, each baffle is trapezium in shape and has a length of from 0.25 mm to 0.55 mm and a width of 0.5 mm.
Fu teaches a microfluidic chemical analysis system device comprising a cross-flow-guiding micro static mixer (paragraph [0002]; Figs. 1-5). Fu teaches purpose of mixing is to reduce heterogeneity, for example for dilution, or to enhance the rate of chemical reactions, so it is very important to achieve fast and efficient mixing (paragraph [0004]). Fu teaches the device comprises a mixing chamber (Figs. 1-3, elements 6 and 7) and the mixing chamber includes baffles (Figs. 1-3, guide blocks 4, 4’, 5, 5’). Fu teaches the mixing chamber comprising at least 12 baffles (Figs. 1-3), 6 of the at least 12 baffles are located on a first side and 6 of the 12 baffles are located on a second side of the mixing chamber (Figs. 1-3). Fu teaches the invention has the following beneficial effects: by arranging alternating guide blocks in the pipeline, shear flow and extension flow can be generated in the flow field, the interface area between different fluids is increased, the molecular diffusion effect is enhanced, and ultimately uniform mixing at the molecular level is achieved (paragraph [0013]).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have modified the mixing chamber of Harvengt to incorporate the teachings of microfluidic devices comprising a mixing chamber with baffles of Fu (Figs. 1-3; paragraph [0013]) to provide: the mixing chamber comprising 12 of the baffles; six of the 12 baffles are located on the first side, six of the 12 baffles are located on the second side. Doing so would have a reasonable expectation of successfully improving mixing as taught by Fu (paragraph [0013]).
Modified Harvengt fails to teach:
the first baffle is located on the first side 4.4 mm from the proximal end of the mixing chamber, the second baffle is located on the second side 6.132 mm from the proximal end of the mixing chamber, each baffle on the first side is separated from the next baffle on the first side by 3.464 mm, each baffle on the second side is separated from the next baffle on the second side by 3.464 mm, each baffle is trapezium in shape and has a length of from 0.25 mm to 0.55 mm and a width of 0.5 mm.
Chen teaches analysis of micromixers with serpentine microchannels (abstract). Chen structural designs of microchannels affect mixing performances (abstract). Chen teaches different types of wall protrusions on microfluidic mixings are known and geometric parameters have an effect on mixing performances (page 132, left column, first paragraph). Chen teaches a microfluidic device (Fig. 4a) where the structural design area for micromixers are located 4.7 mm from an end of a mixing channel (Fig. 1a).
Since Chen teaches a distance of 4.7 mm between an end and a micromixer structure (Fig. 4a) that is merely close to the claimed dimension of 4.4 mm, it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have modified the first baffle modified Harvengt to provide: the first baffle is located on the first side 4.4 mm from the proximal end of the mixing chamber. See MPEP 2144.05 (I). I.e., a prima facie case of obviousness exists where the claimed ranges or amounts do not overlap with the prior art but are merely close (Titanium Metals Corp. of Americav.Banner, 778 F.2d 775, 783, 227 USPQ 773, 779 (Fed. Cir. 1985)).
Modified Harvengt fails to teach:
the second baffle is located on the second side 6.132 mm from the proximal end of the mixing chamber, each baffle on the first side is separated from the next baffle on the first side by 3.464 mm, each baffle on the second side is separated from the next baffle on the second side by 3.464 mm, each baffle is trapezium in shape and has a length of from 0.25 mm to 0.55 mm and a width of 0.5 mm.
Harvengt teaches the mixing chamber should be of adequate length to allow for mixing to be substantially complete by the time liquid reaches the outlet (page 9, line 7-8). Harvengt teaches the mixing chamber has a length of 1-10 cm in length, especially 1.5-5cm (page 9, lines 8-9).
Chen teaches analysis of micromixers with serpentine microchannels (abstract). Chen structural designs of microchannels affect mixing performances (abstract). Chen teaches different types of wall protrusions on microfluidic mixings are known and geometric parameters have an effect on mixing performances (page 132, left column, first paragraph). Chen teaches experimentation of various shapes and sizes of structural areas of structures of a micromixer (section 3.2), which includes distances between structures, lengths of structures, and widths of structures (Fig. 4).
MPEP 2144.05 (II)(B) holds that a particular parameter that is recognized as a result effective variable (“a variable that achieves a recognized result”) would be one, but not the only motivation for a person of ordinary skill in the art to experiment to reach another workable product or process. In the design and fabrication of microfluidic devices, specifically mixing structures, the selection of optimal experimental conditions including structural geometry and dimensions affects fluidic transport parameters which in turn affect mixing performances of desired fluids in a mixing chamber (Chen, page 132, left column, first paragraph). Thus, the location of the baffles, separation distances between the baffles, and length and width of the baffles are a result effective variables.
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have modified the one first inlet channel and the two second inlet channels of modified Harvengt to incorporate the teachings of ranges of the length of the mixing chamber of Harvengt (page 9, lines 8-9) and the teachings of experimentation of various structural designs of micromixers of Chen (page 132, left column, first paragraph; section 3.2; Fig. 4) to provide: the second baffle is located on the second side 6.132 mm from the proximal end of the mixing chamber, each baffle on the first side is separated from the next baffle on the first side by 3.464 mm, each baffle on the second side is separated from the next baffle on the second side by 3.464 mm, each baffle has a length of from 0.25 mm to 0.55 mm and a width of 0.5 mm through routine experimentation (MPEP 2144.05 (II)). I.e., it would have been obvious to design and fabricate the baffles to have modified the result-effective variables, i.e. the location of the baffles, separation distances between the baffles, and length and width of the baffles, to arrive at the claimed invention through routine optimization of workable dimensions for baffles within microchannels to optimize the mixing performance within the mixing chamber to ensure adequate mixing of the solutions.
While Chen teaches different types of wall protrusions on microfluidic mixings are known and geometric parameters have an effect on mixing performances (page 132, left column, first paragraph), and shapes include rectangular, circular, and triangular structures (Fig. 4), modified Harvengt fails to teach: each baffle is trapezium in shape.
Norikane teaches a method using a microfluidic device (Figs. 1-2) comprising the inlets (10, 11), baffles (14), and a mixing chamber (12), comprising the following steps: (a) mixing in the device a first solution and a second solution comprising water (paragraph [0008] teaches merging plural types of fluid that are incompatible with each other; paragraph [0099] teaches surfactant is mixed with water). Norikane teaches the baffles (Fig. 1) are trapezium in shape (Fig. 1; paragraph [0018]).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have modified each baffle of modified Harvengt to incorporate the teachings of mixing structures being different shapes of Chen (Fig. 4) and trapezium baffles of Norikane (Fig. 1) to provide: each baffle is trapezium in shape. Doing so would have a reasonable expectation of successfully allowing for mixing of fluids within the chamber. Additionally, doing so would have been a mere change in shape of each baffle, where the trapezium shape would have been an obvious matter of choice in view of Chen and Norikane (MPEP 2144.04 (IV)(B); In reDailey, 357 F.2d 669, 149 USPQ 47 (CCPA 1966)).
Conclusion
The prior art made of record and not relied upon is considered pertinent to applicant's disclosure.
Xia et al. (CN 202199279 U; see machine translation).teaches a microfluidic mixing system (paragraph [0002]; Figs. 1-2). Xia teaches the mixing system comprises baffles (Figs. 1-2 and paragraph [0029], baffle structures 5), wherein the baffles are 60 um thick and 150 um (paragraph [0029]).
Hai et al., (Hai Le The et al., “Geometric effects on mixing performance in a novel passive micromixer with trapezoidal-zigzag channels“, 2015 J. Micromech. Microeng. 25 094004) teaches a passive micromixer including trapezoidal channels (abstract).
Haghighinia et al. (Haghighinia et al., “Fluid micro-mixing in a passive microchannel: Comparison of 2D and 3D numerical simulations”, International Journal of Heat and Mass Transfer 139 (2019) 907-916) teaches mixing in microchannels including barriers in micromixers (abstract). Haghighinia teaches a microfluidic device including two inlets (Fig. 2), a mixing channel (Fig. 2) including baffles (Fig. 2).
Gidde et al. (Gidde et al., “Evaluation of the mixing performance in a planar passive micromixer with circular and square mixing chamber”, Microsystem Technologies (2018) 24:2599–2610) teaches passive planar micromixers with mixing chambers (abstract; Fig. 1) including multiple inlets, an outlet, and baffles (Fig. 1).
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/HENRY H NGUYEN/Primary Examiner, Art Unit 1758