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 .
Response to Amendment
The Amendment filed 10/21/2025 has been entered. Claims 1-6 and 9-22 remain pending in the application. Claims 12-19 are withdrawn. New grounds of rejections necessitated by amendments are discussed below.
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 1-6, 9-11, and 20-22 are rejected under 35 U.S.C. 103 as being unpatentable over Che et al. (Che et al. “Biophysical isolation and identification of circulating tumor cells” Lab Chip, 2017, 17, 1452) in view of Takakura et al. (WO 2015151226 A1, see machine translation), and Pierzchalski et al. (Pierzchalski et al. “Label-free single cell analysis with a chip-based impedance flow cytometer ” Proc. of SPIE Vol. 7568 75681B-2 (2010)).
Regarding claim 1, Che teaches a system (Fig. 1) for isolating and enumerating cells or particles from a fluid (interpreted as an intended use, see MPEP 2114; abstract) comprising:
a microfluidic chip (Figs. 1B, 1C, “Vortex HT”) for isolating the cells or particles (interpreted as an intended use, see MPEP 2114; abstract; page 1453, last paragraph - page 1554, first paragraph teaches the Vortex Chip, i.e. Vortex HT, “isolates large CTCs”) comprising:
a substrate (Fig. 1B); and
at least one microfluidic channel (Figs. 1B-1D, microchannels between “inlets” and “HT outlet”) disposed in the substrate between an inlet (“Inlets”) and an outlet (“HT outlet”) and having a length (Fig. 1C), the microfluidic channel comprising at least one expansion region (Fig. 1D) disposed along the length of the microfluidic channel (Fig. 1C), the microfluidic channel being configured to generate a vortex within the at least one expansion region in response to fluid flowing through the microfluidic channel (interpreted as an intended use, see MPEP 2114; p 1455, col 1, first paragraph teaches vortices in Fig. 1D).
Che further discloses a deformability cytometric (DC) chip, as a detection chip, fluidically connected to the microfluidic chip (Fig 1B) to characterize biophysical properties of circulating tumor cells (CTC) (abstract); the coupling of vortex CTC enrichment and downstream technologies may prove useful for linking to other platforms for alternative modes of single-cell analyses (p 1459, col 1, first full paragraph); and deformability cytometry and impedance-based detection are used for CTC detection as alternatives to immunofluorescence (p 1458, col 2, last paragraph).
Che fails to teach:
an impedance chip fluidly connected to the microfluidic chip, the impedance chip comprising:
an electrode region for enumerating the cells or particles, the electrode region comprising:
a first electrode;
a second electrode; and
a channel through which the cells or particles flow along a path of travel, the channel decreasing in size between the first electrode and the second electrode to form a channel restriction, the channel restriction configured to have a size greater than the cells or particles, the first electrode being separated from the second electrode along the path of travel, the first and electrode and second electrode measuring a decrease in base current as a cell or particle passes through the channel restriction;
a voltage source for producing current, the voltage source configured to apply an alternating current to the cells or particles; and
an inertial focusing region, the inertial focusing region being directly upstream of the electrode region, wherein the inertial focusing region comprises a second microfluidic channel through which the cells or particles pass;
wherein the second microfluidic channel has a cross-sectional area that is defined by a width and a height of the second microfluidic channel, wherein at least one of the width or the height is no more than 40 um.
Takakura teaches a separation channel and particle detector (abstract) comprising an impedance chip (Fig. 1) comprising an electrode region (Fig. 1, region of elements 1, 5, 6) comprising a first electrode (5), second electrode (6), and a channel (Fig. 1 shows a channel including elements 5, 1, and 6) decreasing in size between the first electrode and the second electrode to form a channel restriction (Fig. 1 shows a channel restriction, pore 1, which is a decrease in size of the overall channel between the electrodes 5 and 6), the channel configured to have a size greater than cells or particles (Fig. 1), the first electrode being separated from the second electrode along the path of travel (Fig. 1). Takakura teaches that decreases or increases in pulse-like signal of current is possible (page 7, last paragraph — page 8, first paragraph). Takakura teaches that the number of particles can be measured by counting current pulses generated when particles pass through pores (page 8, last paragraph). Takakura teaches a voltage source (Fig. 1, voltage source 3) capable of producing current and capable of applying an alternating current to the cells or particles (page 8, first paragraph teaches that alternating current impedance is measured, which implies the voltage source is capable of producing an alternating current for measurement). Takakura teaches the channel and detector allows for particles to be measured non-destructively and with high sensitivity (abstract).
Pierzchalski is in the analogous art of impedance detection of cellular responses in micro-environments (abstract) and discloses a method where an impedance chip (Fig. 2) has a sample comprising cells (p. 3, fourth full paragraph) and an alternating current is applied to the sample (p. 4, first full paragraph). Pierzchalski teaches the impedance chip comprising an electrode region (Fig. 2, electrodes) for enumerating cells or particles (p. 4, section 3 teaches that as a particle passes through the electrodes, a change in electric field is recorded, thus the electrodes is capable of enumerating cells or particles; Fig. 11), the electrode region comprising: a first electrode (Fig. 2, interpreted as one of the electrode pairs, e.g. the excitation electrode of the left electrode pair on the top left side of Fig. 2); a second electrode (Fig. 2, interpreted as one of the electrode pairs, e.g. the excitation electrode of the right electrode pair on the top right side of Fig. 2); and a channel (Fig. 2) through which cells or particles flow along a path of travel (Fig. 2), the electrodes capable of measuring a decrease in base current as a cell or particle passes through the channel restriction (p. 4, section 3 teaches that as a particle passes through the electrodes, a change in electric field is recorded; Fig. 2, “impedance measurement”). Pierzchalski teaches for impedance analysis, multiple different frequencies can be simultaneously measured (p. 4, first full paragraph) which provide information on different properties of the cell (Fig 4). At higher frequencies, there is sufficient resolution to distinguish between viable cells, necrotic cells, and apoptotic cells (Figs 8A-B). This allows for identification and discrimination of cell subpopulations without any labels (p 9, second full paragraph). Combining impedance flow cytometry with other cell analysis systems could provide unequivocal identification of sub-populations and enable more reliable cell characterization (p 9, fifth paragraph).
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 system of Che to incorporate the teachings of an impedance chip comprising an electrode region with a channel restriction between two electrodes along a path of travel, measuring alternating current impedance, and measuring the number of particles of Takakura (Fig. 1; page 8, first paragraph; page 8, last paragraph), the teachings of analyzing impedance of cells flowing through a channel using electrodes (Pierzchalski, Fig. 2; p. 4, section 3) and combining impedance flow cytometry with other cell analysis systems of Pierzchalski (p 9, fifth paragraph), and the teachings of linking platforms for alternative modes of cell analyses and impedance based detection of cells of Che (p 1459, col 1, first full paragraph; p 1458, col 2, last paragraph) to provide: an impedance chip fluidly connected to the microfluidic chip, the impedance chip comprising: an electrode region for enumerating the cells or particles, the electrode region comprising: a first electrode; a second electrode; and a channel through which the cells or particles flow along a path of travel, the channel decreasing in size between the first electrode and the second electrode to form a channel restriction, the channel restriction configured to have a size greater than the cells or particles, the first electrode being separated from the second electrode along the path of travel, the first electrode and second electrode measuring a decrease in base current as a cell or particle passes through the channel restriction; and a voltage source for producing current, the voltage source configured to apply an alternating current to the cells or particles. Doing so would have a reasonable expectation of successfully improving analysis of particles by allowing for counting of particles with high sensitivity as taught by Takakura (abstract) and allowing for more reliable cell characterization (Pierzchalski, p 9, fifth paragraph). Additionally, one of ordinary skill in the art would have been motivated to modify the system of Che to incorporate the impedance chip, electrode region, and voltage source of Takakura to arrive at the claimed invention since Pierzchalski discusses that combining impedance flow cytometry with other cell analysis systems, e.g. a cell counting system, could provide unequivocal identification of sub-populations and enable more reliable cell characterization (p 9, fifth paragraph).
Furthermore, the claimed limitations are obvious because all of the claimed elements were known in the prior art and one skilled in the art could have combined the elements (i.e. a system comprising a microfluidic chip and impedance chip, where the impedance chip comprises an electrode region as claimed) by known methods with no change in their respective functions (i.e. isolating and counting cells), and the combinations yielded nothing more than predictable results (i.e. adding an impedance chip as claimed to Che’s system would yield nothing more than the obvious and predictable result of allowing for counting of particles with high sensitivity and enabling more reliable cell characterization). See MPEP 2143(A).
While Che teaches a region with channels to first inertially focus and direct cells towards one side of the device and then focus cells to a single stream in which they may be oriented towards a center of a channel prior to a DC junction (page 1455, left column, first full paragraph), modified Che fails to teach the impedance chip comprising: an inertial focusing region, the inertial focusing region being directly upstream of the electrode region, wherein the inertial focusing region comprises a second microfluidic channel through which the cells or particles pass; wherein the second microfluidic channel has a cross-sectional area that is defined by a width and a height of the second microfluidic channel, wherein at least one of the width or the height is no more than 40 um.
Takakura teaches a separation channel and particle detector (abstract) comprising an impedance chip (Fig. 1) comprising an electrode region (Fig. 1, region of elements 1, 5, 6). Takakura teaches the impedance chip comprises an inertial focusing region (Fig. 1, region to the left of, i.e. upstream, of element 5, wherein the region is structurally capable of “inertial focusing”), the inertial focusing region being directly upstream of the electrode region (Fig. 1, region to the left of and upstream of element 5 is interpreted as directly upstream of the region of elements 1, 5, 6).
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 impedance chip of modified Che to incorporate the teachings of an impedance chip comprising an electrode region and inertial focusing region of Takakura (Fig. 1) and the teachings of a region with channels to first inertially focus and direct cells towards one side of the device and then focus cells to a single stream in which they may be oriented towards a center of a channel prior to a DC junction of Che (page 1455, left column, first full paragraph), to provide: the impedance chip comprising: an inertial focusing region, the inertial focusing region being directly upstream of the electrode region, wherein the inertial focusing region comprises a second microfluidic channel through which the cells or particles pass; wherein the second microfluidic channel has a cross-sectional area that is defined by a width and a height of the second microfluidic channel. Doing so would have a reasonable expectation of successfully improving analysis of particles by allowing for improved focusing or orientation of particles within a stream (Che, page 1455, left column, first full paragraph) and improved counting of particles with high sensitivity (Takakura, abstract).
Furthermore, the claimed limitations are obvious because all of the claimed elements were known in the prior art and one skilled in the art could have combined the elements (i.e. a system comprising a microfluidic chip and impedance chip, where the impedance chip comprises an electrode region and inertial focusing region as claimed) by known methods with no change in their respective functions (i.e. isolating and counting cells), and the combinations yielded nothing more than predictable results (i.e. adding the inertial focusing region as claimed to modified Che’s system would yield nothing more than the obvious and predictable result of allowing for focusing of cells in a stream and counting of particles with high sensitivity and enabling more reliable cell characterization). See MPEP 2143(A).
Modified Che fails to teach: the second microfluidic channel wherein at least one of the width or the height is no more than 40 um.
Toner teaches systems for focusing particles within a moving fluid into one or more localized stream lines with inertial forces (abstract). Toner teaches high cell viability and throughput are critical for flow cytometry and inertial self-ordering has clear advantages for flow cytometry, including a single stream input, reduction of multiple cells in an interrogation spot, and angular orientation of nonspherical particles for uniform scatter profiles (column 44, lines 12-19). Toner teaches channels for a focused stream can have a width of less than or equal to 50 micrometers, 20 micrometers, and/or 10 micrometers (column 3, lines 41-46).
Since Toner teaches an inertial focusing channel with a width range of less than or equal 50, 20 and/or 10 um (column 3, lines 41-46), which overlaps the claimed range of no more than 40 um, 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 second channel of modified Che to provide the second microfluidic channel wherein at least one of the width or the height is no more than 40 um with a reasonable expectation of successfully improving focusing of cells for analysis (Toner, column 44, lines 12-19). I.e., it would have been prima facia obvious to have selected the overlapping portion of the range (i.e. no more than 40 um) from the taught range of less than or equal to 50, 20 and/or 10 um (Toner, column 3, lines 41-46) (In re Wertheim, 541 F.2d 257, 191 USPQ 90 (CCPA 1976); see MPEP 2144.05 (I)).
Regarding claim 2, Che further teaches the system as set forth in claim 1 comprising a switch (p 1454, col 2, last paragraph, “Device operation and workflow” - p 1455, col 1, first full paragraph teaches opening or closing outlets, which implies a structure that operates as a switch for opening or closing) between a DC region and the microfluidic chip (Figs. 1B-1C shows “HT outlet” between the Vortex DC and DC regions).
Modified Che fails to teach the switch between the impedance chip and the microfluidic chip.
Che teaches device operation and workflow (p 1454-1455, section “Device operation and workflow”) where specific outlets are closed or opened to guide cells to specific regions, to allow waste to pass, and to flush cells to a collection vessel (p 1454-1455, section “Device operation and workflow”). Che teaches waste passes through the HT outlet during cell capture, and enriched cells pass through an initial biasing inertial focuser and a final alignment inertial focuser to arrive centered at the DC junction from one side and then out the 2 DC outlets during cell release (Fig. 1 caption). Che teaches the coupling of vortex CTC enrichment and downstream technologies may prove useful for linking to other platforms for alternative modes of single-cell analyses (p 1459, col 1, first full paragraph).
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 switch of modified Che to incorporate the teachings of opening and closing outlets to guide fluids or cells to desired regions of Che (p 1454-1455, section “Device operation and workflow”; Fig. 1 caption) to provide the switch between the impedance chip and the microfluidic chip. Doing so would have a reasonable expectation of successfully improving control of cells or fluids to desired regions downstream of the microfluidic chip, such as towards or away from the impedance chip.
Regarding claim 3, modified Che further teaches wherein the switch selectively directs material discharged from the microfluidic chip (1) to a waste vessel or (2) to the impedance chip (interpreted as an intended use of the claimed switch, see MPEP 2114; Che, p 1454-1455, section “Device operation and workflow” teaches specific outlets are closed or opened to guide cells to specific regions, to allow waste to pass, and to flush cells to a collection vessel, and Fig. 1 teaches waste passes through the HT outlet during cell capture; thus, the structure for opening/closing the outlets, i.e. switch, is capable of selectively directing material from the microfluidic chip to a waste vessel or the impedance chip at a later time).
Regarding claim 4, Che further teaches wherein the substrate is a rigid substrate (Fig. 1B; note that the instant specification, paragraph [00129] describes “rigid” as being resistant to deformation under pressure of fluid flow; therefore, since Che’s Fig. 1B shows fluid flow through the substrate, it is implied that the substrate is rigid or resistant to deformation under pressure of fluid flow since the fluidic structures are not deforming during use).
Regarding claim 5, Che further teaches wherein the microfluidic chip is disposed within a cartridge (Fig. 1B shows the Vortex HT disposed within a cartridge).
Modified Che fails to explicitly teach: the impedance chip is within the cartridge.
Che teaches a DC chip disposed within the cartridge (Fig. 1B shows “DC” is integrated within the cartridge). Che teaches coupling of vortex CTC enrichment and downstream technologies may prove useful for linking to other platforms for alternative modes of single-cell analyses (p 1459, col 1, first full paragraph).
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 impedance chip of modified Che to incorporate the teachings of a second chip or region disposed within a cartridge of Che (Fig. 1B) and the teachings of linking other platforms downstream of Che (p 1459, col 1, first full paragraph) to provide the impedance chip is within the cartridge. Doing so would have a reasonable expectation of successfully integrating the impedance chip with the microfluidic chip within the same device, i.e. cartridge, to improve coupling of platforms for improved cell analysis as discussed by Che (p 1459, col 1, first full paragraph).
Regarding claim 6, Che further teaches wherein the cartridge (Fig. 1B) is removably connectable to a biopsy system for isolating and enumerating the cells or particles from the fluid (interpreted as a functional limitation and intended use of the claimed cartridge, see MPEP 2114; note that the “biopsy system” is not positively claim structurally; Fig. 1B shows the cartridge comprising inlets and outlets which are structurally capable of being removably connectable to a biopsy system at a later time).
Regarding claim 9, modified Che further teaches wherein the impedance chip is free of facing electrodes (see above claim 1, the modification includes the impedance chip of Takakura; Takakura, Figs. 1 and 9 teach a coplanar electrode arrangement free of facing electrodes).
Regarding claim 10, modified Che further teaches wherein the cells or particles from the fluid are circulating tumor cells having a size of 10 to 30 um (Che, abstract; Fig. 3 teaches CTCs in the range of 10-30 um; note that “cell or particles” are not positively recited structurally), the channel restriction being configured to have a size greater than the circulating tumor cells (see above claim 1, the modification includes the impedance chip of Takakura; Takakura, Fig. 1 shows the channel restriction, i.e. pore 1, having a size greater than a particle).
If it is determined that modified Che fails to explicitly teach the channel restriction being configured to have a size greater than the circulating tumor cells, Takakura teaches a channel restriction being configured to have a size greater than a particle (Fig. 1 shows the channel restriction, i.e. pore 1, having a size greater than a particle). Takakura teaches that the number of particles can be measured by counting current pulses generated when particles pass through pores (page 8, last paragraph). Takakura teaches the channel and detector allows for particles to be measured non-destructively and with high sensitivity (abstract).
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 channel restriction of modified Che to incorporate the teachings of a channel restriction having a size greater than a particle of Takakura (Fig. 1) to provide the channel restriction being configured to have a size greater than the circulating tumor cells. Doing so would have a reasonable expectation of successfully allowing a particle to be analyzed to pass through the channel restriction and allowing for circulating tumor cells to be measured non-destructively and with high sensitivity (Takakura, abstract; page 8, last paragraph).
Regarding claim 11, modified Che fails to explicitly teach wherein the channel restriction is configured to have a size of 40 um.
Che teaches cell or particle sizes of larger than 15 um (abstract), such as CTCs between 10-30 um and a channel of a vortex region being 70 um deep and 40 um wide (p 1454, column 1, last paragraph).
Takakura teaches particles size can range from 1nm to 1mm (page 3, first paragraph). Takakura teaches a channel restriction being configured to have a size greater than a particle (Fig. 1 shows the channel restriction, i.e. pore 1, having a size greater than a particle).
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 channel restriction of modified Che to incorporate the teachings of particle sizes and channel region sizes of Che (abstract; p 1454, column 1, last paragraph) and the teachings of particle sizes and a channel restriction being larger than a particle of Takakura (Fig. 1; page 3, first paragraph) to provide wherein the channel restriction is configured to have a size of 40 um. Doing so would have a reasonable expectation of successfully allowing a particle to be analyzed to pass through the channel restriction and allowing for particles to be measured non-destructively and with high sensitivity (Takakura, abstract; page 8, last paragraph). Additionally, one of ordinary skill in the art would have arrived at the claimed dimension through routine experimentation (see MPEP 2144.05 (II)) to optimize the size of the channel restriction to be larger than the cell or particles as shown by Takakura (Fig. 1) and Pierzchalski (Fig. 2).
Regarding claim 20, modified Che fails to teach: wherein at least one of the width or the height of the second microfluidic channel is 40 um.
Toner teaches systems for focusing particles within a moving fluid into one or more localized stream lines with inertial forces (abstract). Toner teaches high cell viability and throughput are critical for flow cytometry and inertial self-ordering has clear advantages for flow cytometry, including a single stream input, reduction of multiple cells in an interrogation spot, and angular orientation of nonspherical particles for uniform scatter profiles (column 44, lines 12-19). Toner teaches channels for a focused stream can have a width of less than or equal to 50 micrometers, 20 micrometers, and/or 10 micrometers (column 3, lines 41-46).
Since Toner teaches an inertial focusing channel with a width range of less than or equal 50 um (column 3, lines 41-46), which overlaps the claimed dimension of 40 um, 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 second channel of modified Che to provide wherein at least one of the width or the height of the second microfluidic channel is 40 um with a reasonable expectation of successfully improving focusing of cells for analysis (Toner, column 44, lines 12-19). I.e., it would have been prima facia obvious to have selected the overlapping portion of the range (i.e. 40 um) from the taught range of less than or equal to 50 um (Toner, column 3, lines 41-46) (In re Wertheim, 541 F.2d 257, 191 USPQ 90 (CCPA 1976); see MPEP 2144.05 (I)).
Regarding claim 21, modified Che fails to teach: wherein the height of the second microfluidic channel is no more than 70 um and the width of the second microfluidic channel is no more than 40 um.
Toner teaches systems for focusing particles within a moving fluid into one or more localized stream lines with inertial forces (abstract). Toner teaches high cell viability and throughput are critical for flow cytometry and inertial self-ordering has clear advantages for flow cytometry, including a single stream input, reduction of multiple cells in an interrogation spot, and angular orientation of nonspherical particles for uniform scatter profiles (column 44, lines 12-19). Toner teaches channels for a focused stream can have a width of less than or equal to 50 micrometers, 20 micrometers, and/or 10 micrometers (column 3, lines 41-46). Toner teaches an embodiment where the channel has a rectangular cross-section with an aspect ratio of 1 to 1 (column 16, lines 11-14). Toner teaches an embodiment where the rectangular cross-section has an aspect ratio of between 0.3 and 0.8 and/or 1 to 2 (column 4, lines 31-35).
Since Toner teaches an inertial focusing channel with a width range of less than or equal 50 um (column 3, lines 41-46), which overlaps the claimed dimension of a height that is no more than 70 um and a width that is no more than 40 um, 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 second channel of modified Che to provide wherein the height of the second microfluidic channel is no more than 70 um and the width of the second microfluidic channel is no more than 40 um with a reasonable expectation of successfully improving focusing of cells for analysis (Toner, column 44, lines 12-19). I.e., it would have been prima facia obvious to have selected the overlapping portion of the range from the taught range of less than or equal to 50 um (Toner, column 3, lines 41-46) (In re Wertheim, 541 F.2d 257, 191 USPQ 90 (CCPA 1976); see MPEP 2144.05 (I)).
Regarding claim 22, modified Che fails to teach: wherein the height of the second microfluidic channel is 70 um and the width of the second microfluidic channel is 40 um.
Toner teaches systems for focusing particles within a moving fluid into one or more localized stream lines with inertial forces (abstract). Toner teaches high cell viability and throughput are critical for flow cytometry and inertial self-ordering has clear advantages for flow cytometry, including a single stream input, reduction of multiple cells in an interrogation spot, and angular orientation of nonspherical particles for uniform scatter profiles (column 44, lines 12-19). Toner teaches channels for a focused stream can have a width of less than or equal to 80 micrometers, 50 micrometers, 20 micrometers, and/or 10 micrometers (column 3, lines 41-46). Toner teaches an embodiment where the rectangular cross-section has an aspect ratio of between 0.3 and 0.8 and/or 1 to 2 (column 4, lines 31-35).
Since Toner teaches an inertial focusing channel with a width range of less than or equal 80 um (column 3, lines 41-46) and aspect ratios between the dimensions of a rectangular cross-section of the channel of between 0.3 and 0.8 and/or 1 to 2 (column 4, lines 31-35), which overlaps the claimed dimension of the height and the width, 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 second channel of modified Che to provide wherein the height of the second microfluidic channel is 70 um and the width of the second microfluidic channel is 40 um with a reasonable expectation of successfully improving focusing of cells for analysis (Toner, column 44, lines 12-19). I.e., it would have been prima facia obvious to have selected the overlapping dimensions from the taught ranges of channel width and height based on the range of aspect ratios (Toner, column 3, lines 41-46 and column 4, lines 31-35) (In re Wertheim, 541 F.2d 257, 191 USPQ 90 (CCPA 1976); see MPEP 2144.05 (I)).
Claims 1-6, 9-11, and 20-22 are rejected under 35 U.S.C. 103 as being unpatentable over Di Carlo et al. (WO 2015200857 A1) in view of Takakura et al. (WO 2015151226 A1, see machine translation), in view of Toner et al. (US 8807879 B2).
Regarding claim 1, Di Carlo teaches a system (Fig. 3) for isolating and enumerating cells or particles from a fluid (interpreted as an intended use, see MPEP 2114; paragraph [0016] teaches the system counts cells from a fluid) comprising:
a microfluidic chip (Fig. 3A and paragraphs [0029],[0032] teaches purification device 12, which is a microfluidic chip) for isolating cells or particles (interpreted as an intended use, see MPEP 2114; paragraph [0032] teaches the purification device traps cells, i.e. isolates cells or particles) comprising:
a substrate (Fig 3A and paragraph [0028] interpreted as the substrate of purification device 12); and
at least one microfluidic channel disposed in the substrate (Fig. 3A, microfluidic channels 16 in purification device 16) between an inlet (18) and an outlet (26) and having a length (Fig. 3A), the microfluidic channel comprising at least one expansion region disposed along the length of the microfluidic channel (expansion regions 28), the microfluidic channel being configured to generate a vortex within the at least one expansion region in response to fluid flowing through the microfluidic channel (interpreted as an intended use, see MPEP 2114; Fig. 1D and paragraphs [0029], [0051] teach vortices are created within expansion regions 28 via fluid flowing through the microfluidic channels 16); and
an impedance unit (Fig. 3A shows a cell analysis device 14 comprising an impedance measurement circuitry 68, electrodes 66, and an outlet channel downstream of outlet 26 of the purification device 12) fluidly connected to the microfluidic chip (Fig. 3A shows the channel downstream of outlet 26 is fluidly connected to the purification device 12), the impedance unit comprising:
an electrode region (Fig. 3B, region of elements 66) for enumerating the cells or particles (interpreted as an intended use of the electrode region, see MPEP 2114; paragraph [0044] teaches the electrodes are for counting cells), the electrode region comprising:
a first electrode (Fig. 3B, one of electrodes 66b);
a second electrode (Fig. 3B, another one of electrodes 66b); and
the first electrode being separated from the second electrode along the path of travel (Fig. 3B shows one of electrode 66b downstream of another electrode 66b); and
a voltage source (Fig. 3B, function or signal generator 70) for producing current (interpreted as an intended use; paragraph [0044] teaches the function or signal generator applies an AC signal), the voltage source configured to apply an alternating current to the cells or particles (interpreted as functional limitation; Fig. 3B and paragraph [0044] teaches the function or signal generator applies an AC signal to electrodes, therefore applying AC signal to cells or particles within the channel).
Di Carlo fails to teach: the impedance unit is an impedance chip; the electrode region comprising: a channel through which the cells or particles flow along a path of travel, the channel decreasing in size between the first electrode and the second electrode to form a channel restriction, the channel restriction configured to have a size greater than the cells or particles, the first electrode and second electrode measuring a decrease in base current as a cell or particle passes through the channel restriction; and the impedance chip comprising an inertial focusing region, the inertial focusing region being directly upstream of the electrode region, wherein the inertial focusing region comprises a second microfluidic channel through which the cells or particles pass; wherein the second microfluidic channel has a cross-sectional area that is defined by a width and a height of the second microfluidic channel, wherein at least one of the width or the height is no more than 40 um.
Di Carlo teaches the purification device 12 is a microfluidic device, which can release trapped cells that travel to a separate cell analysis device 14 (paragraph [0032]). Di Carlo teaches an embodiment wherein trapped cells are released to be subject to further analysis (Fig. 1B; paragraph [0030]).
Takakura teaches a separation channel and particle detector (abstract) comprising an impedance chip (Fig. 1) comprising an electrode region (Fig. 1, region of elements 1, 5, 6) comprising a first electrode (5), second electrode (6), and a channel (Fig. 1 shows a channel including elements 5, 1, and 6) decreasing in size between the first electrode and the second electrode to form a channel restriction (Fig. 1 shows a channel restriction, pore 1, which is a decrease in size of the overall channel between the electrodes 5 and 6), the channel configured to have a size greater than cells or particles (Fig. 1), the first electrode being separated from the second electrode along the path of travel (Fig. 1). Takakura teaches that decreases or increases in pulse-like signal of current is possible (page 7, last paragraph — page 8, first paragraph). Takakura teaches that the number of particles can be measured by counting current pulses generated when particles pass through pores (page 8, last paragraph). Takakura teaches a voltage source (Fig. 1, voltage source 3) capable of producing current and capable of applying an alternating current to the cells or particles (page 8, first paragraph teaches that alternating current impedance is measured, which implies the voltage source is capable of producing an alternating current for measurement). Takakura teaches the channel and detector allows for particles to be measured non-destructively and with high sensitivity (abstract).
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 system and electrode region of Di Carlo to incorporate the teachings of an impedance chip comprising an electrode region with a channel restriction between two electrodes along a path of travel, measuring alternating current impedance, and measuring the number of particles of Takakura (Fig. 1; page 8, first paragraph; page 8, last paragraph) and the teachings of a system that releases cells from the microfluidic chip to a separate cell analysis device of Di Carlo (paragraphs [0030],[0032]; Fig. 1B), to provide: the impedance unit as an impedance chip; the electrode region comprising: a channel through which the cells or particles flow along a path of travel, the channel decreasing in size between the first electrode and the second electrode to form a channel restriction, the channel restriction configured to have a size greater than the cells or particles, the first electrode and second electrode measuring a decrease in base current as a cell or particle passes through the channel restriction. Doing so would have a reasonable expectation of successfully improving analysis of particles by allowing for counting of particles with high sensitivity as taught by Takakura (abstract).
Furthermore, the claimed limitations are obvious because all of the claimed elements were known in the prior art and one skilled in the art could have combined the elements (i.e. a system comprising a microfluidic chip and impedance chip, where the impedance chip comprises an electrode region as claimed) by known methods with no change in their respective functions (i.e. isolating and counting cells via electrodes), and the combinations yielded nothing more than predictable results (i.e. adding an impedance chip as claimed to Di Carlo’s system would yield nothing more than the obvious and predictable result of allowing for counting of particles with high sensitivity and enabling more reliable cell characterization downstream of the microfluidic chip). See MPEP 2143(A).
While Di Carlo teaches microchannels act as focusing microchannels (paragraph [0028]), modified Di Carlo fails to teach: the impedance chip comprising an inertial focusing region, the inertial focusing region being directly upstream of the electrode region, wherein the inertial focusing region comprises a second microfluidic channel through which the cells or particles pass; wherein the second microfluidic channel has a cross-sectional area that is defined by a width and a height of the second microfluidic channel, wherein at least one of the width or the height is no more than 40 um.
Takakura teaches a separation channel and particle detector (abstract) comprising an impedance chip (Fig. 1) comprising an electrode region (Fig. 1, region of elements 1, 5, 6). Takakura teaches the impedance chip comprises an inertial focusing region (Fig. 1, region to the left of, i.e. upstream, of element 5, wherein the region is structurally capable of “inertial focusing”), the inertial focusing region being directly upstream of the electrode region (Fig. 1, region to the left of and upstream of element 5 is interpreted as directly upstream of the region of elements 1, 5, 6).
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 impedance of modified Di Carlo to incorporate the teachings of an impedance chip comprising an electrode region and inertial focusing region of Takakura (Fig. 1) and the teachings of focusing microchannels of Di Carlo (paragraph [0028]) to provide: the impedance chip comprising an inertial focusing region, the inertial focusing region being directly upstream of the electrode region, wherein the inertial focusing region comprises a second microfluidic channel through which the cells or particles pass; wherein the second microfluidic channel has a cross-sectional area that is defined by a width and a height of the second microfluidic channel. Doing so would have a reasonable expectation of successfully improving focusing and analysis of particles by allowing for counting of particles with high sensitivity as taught by Takakura (abstract).
Furthermore, the claimed limitations are obvious because all of the claimed elements were known in the prior art and one skilled in the art could have combined the elements (i.e. a system comprising a microfluidic chip and impedance chip, where the impedance chip comprises an electrode region and inertial focusing region as claimed) by known methods with no change in their respective functions (i.e. isolating and counting cells), and the combinations yielded nothing more than predictable results (i.e. adding the inertial focusing region as claimed to modified Di Carlo’s system would yield nothing more than the obvious and predictable result of allowing for focusing and counting of particles with high sensitivity and enabling more reliable cell characterization). See MPEP 2143(A).
Modified Di Carlo fails to teach: the second microfluidic channel wherein at least one of the width or the height is no more than 40 um.
Di Carlo teaches focusing microchannels, wherein the channels have a height, in the out of plane direction, within the range of 40-80 um and a width less than 40 um and an aspect ratio defined by the ratio of height to width of > 1.5 (paragraph [0028]).
Since Di Carlo teaches a focusing microchannel with a width less than 40 um, which overlaps the claimed range of no more than 40 um, 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 second channel of modified Di Carlo to provide the second microfluidic channel wherein at least one of the width or the height is no more than 40 um. I.e., it would have been prima facia obvious to have selected the overlapping portion of the range (i.e. no more than 40 um) from the taught range of a width less than 40 um (Di Carlo, paragraph [0028]) (In re Wertheim, 541 F.2d 257, 191 USPQ 90 (CCPA 1976); see MPEP 2144.05 (I)).
Regarding claim 2, modified Di Carlo fails to teach the system as set forth in claim 1 comprising a switch between the impedance chip and the microfluidic chip.
Di Carlo teaches the purification device 12 is a microfluidic device, which can release trapped cells that travel to a separate cell analysis device 14 (paragraph [0032]). Di Carlo teaches an embodiment wherein trapped cells are released to be subject to further analysis (Fig. 1B; paragraph [0030]). Di Carlo teaches a valve, i.e. switch, may be used to direct cells to downstream processing (paragraph [0030]). Di Carlo teaches an embodiment wherein cells can be released in a side chamber and then released outside the chip afterwards for downstream applications, wherein such processes would be enabled by the integration of valves into the device (paragraph [0052]). Di Carlo teaches an embodiment wherein the outlet of the purification device may be coupled to a valve than can be actuated to return concentrated cells back into the system to trap more cells (paragraph [0056]).
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 system of Di Carlo to incorporate the teachings of integrating a valve in the device, such as downstream of the microfluidic chip and prior to further analysis of Di Carlo (paragraphs [0030],[0052],[0056]) to provide: the system as set forth in claim 1 comprising a switch between the impedance chip and the microfluidic chip. Doing so would have a reasonable expectation of successfully improving control of cells or fluids to desired regions downstream of the microfluidic chip, such as towards or away from the impedance chip.
Regarding claim 3, modified Di Carlo fails to teach: wherein the switch selectively directs material discharged from the microfluidic chip (1) to a waste vessel or (2) to the impedance chip.
Di Carlo teaches the purification device 12 is a microfluidic device, which can release trapped cells that travel to a separate cell analysis device 14 (paragraph [0032]). Di Carlo teaches an embodiment wherein trapped cells are released to be subject to further analysis (Fig. 1B; paragraph [0030]). Di Carlo teaches a valve, i.e. switch, may be used to direct cells to waste or downstream processing (paragraph [0030]). Di Carlo teaches an embodiment wherein cells can be released in a side chamber and then released outside the chip afterwards for downstream applications, wherein such processes would be enabled by the integration of valves into the device (paragraph [0052]). Di Carlo teaches an embodiment wherein the outlet of the purification device may be coupled to a valve than can be actuated to return concentrated cells back into the system to trap more cells (paragraph [0056]). Di Carlo teaches downstream paths include further analysis and waste (Fig. 1B).
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 system of Di Carlo to incorporate the teachings of integrating a valve in the device, such as downstream of the microfluidic chip and prior to further analysis of Di Carlo (paragraphs [0030],[0052],[0056]) and the teachings of a valve to direct cells to waste or downstream processing of Di Carlo (paragraph [0030]) to provide: wherein the switch selectively directs material discharged from the microfluidic chip (1) to a waste vessel or (2) to the impedance chip.. Doing so would have a reasonable expectation of successfully improving control of cells or fluids to desired regions downstream of the microfluidic chip, such as towards or away from the impedance chip or a waste vessel.
Regarding claim 4, modified Di Carlo fails to explicitly teach wherein the substrate is a rigid substrate.
Di Carlo teaches the substrate can be made of substrate materials, such as glass and rigid plastics such as COC, PC, and COP (paragraph [0028]).
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 substrate of modified Di Carlo to incorporate the teachings of known rigid materials for a substrate of Di Carlo (paragraph [0028]) to provide wherein the substrate is a rigid substrate. Doing so would have a reasonable expectation of successfully allowing for manufacturing of the microfluidic device.
Additionally, since Di Carlo teaches a need to select materials for manufacturing the microfluidic device (paragraph [0028] making the microfluidic device with substrate materials, therefore there is a need to select proper materials for manufacturing the microfluidic device), and Di Carlo provides a finite number of identified predictable solutions for materials for the substrate of the microfluidic device (paragraph [0028]), it would have been obvious to one of ordinary skill in the art to have modified the substrate of modified Di Carlo to incorporate the teachings of known rigid materials for a substrate of Di Carlo (paragraph [0028]) to provide wherein the substrate is a rigid substrate. Doing so would have a reasonable expectation of successfully allowing for manufacturing of the microfluidic device. See MPEP 2143(I).
Regarding claim 5, modified Di Carlo fails to explicitly teach wherein the microfluidic chip and impedance chip are disposed within a cartridge.
Di Carlo teaches that the purification device 12 and/or cell analysis device 14 are implemented in a microfluidic platform or multiple microfluidic platforms that are integrated together (paragraph [0032]), wherein integrated platforms together are interpreted as a cartridge. Di Carlo teaches an embodiment (Fig. 4) wherein the purification device and cell analysis device are integrated into a single system (paragraph [0045]; Fig. 4) to provide for devices in a closed system to be fully automated to enable adoption into a clinical setting (paragrap