Ex Parte Di Carlo et al

Patent Trial and Appeal Board

Dec 17, 2018

13988282 (P.T.A.B. Dec. 17, 2018)

UNITED STA TES p A TENT AND TRADEMARK OFFICE
APPLICATION NO. FILING DATE FIRST NAMED INVENTOR
13/988,282 05/17/2013 Dino Di Carlo
23410 7590 12/18/2018
Vista IP Law Group LLP
100 Spectrum Center Drive
Suite 900
IRVINE, CA 92618
UNITED STATES DEPARTMENT OF COMMERCE
United States Patent and Trademark Office
Address: COMMISSIONER FOR PATENTS
P.O. Box 1450
Alexandria, Virginia 22313-1450
www .uspto.gov
ATTORNEY DOCKET NO. CONFIRMATION NO.
2011-038-2US 1039
EXAMINER
WHITE, DENNIS MICHAEL
ART UNIT PAPER NUMBER
1798
MAIL DATE DELIVERY MODE
12/18/2018 PAPER
Please find below and/or attached an Office communication concerning this application or proceeding.
The time period for reply, if any, is set in the attached communication.
PTOL-90A (Rev. 04/07)
UNITED STATES PATENT AND TRADEMARK OFFICE
BEFORE THE PATENT TRIAL AND APPEAL BOARD
Ex parte DINO DI CARLO AND WONHEE LEE
Appeal2017-000312
Application 13/988,282
Technology Center 1700
Before BEYERL YA. FRANKLIN, MICHAEL G. McMANUS, and
JANEE. INGLESE, Administrative Patent Judges.
INGLESE, Administrative Patent Judge.
DECISION ON APPEAL
Appellants 1 request our review under 35 U.S.C. § 134(a) of the
Examiner's decision to reject claims 1-16 and 18-21. We have jurisdiction
over this appeal under 35 U.S.C. § 6(b).
We AFFIRM.
STATEMENT OF THE CASE
Appellants claim a particle focusing system (independent claim 1 ), a
particle analyzing system (independent claim 2), and a method of focusing
particles in a fluid into a substantially axially aligned and ordered particle
stream (independent claim 16). Claim 1 illustrates the subject matter on
1 Appellants identify the Regents of the University of California as the real
party in interest. Appeal Brief filed March 28, 2016 ("App. Br."), 2.
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appeal and is reproduced below with contested language italicized:
1. A particle focusing system, comprising:
a substrate;
an inlet disposed in the substrate and coupled to a source
of fluid having particles having a diameter greater than 1 µm
suspended therein;
an inertial focusing microchannel disposed in the
substrate and connected to the inlet, the inertial focusing
microchannel consisting essentially of a pair of side walls
separated by a width w1, wherein one of the side walls of the
pair includes at least one expansion extending outwardly and
having a width w2 and wherein w2>w1 and further wherein the
at least one expansion returns to a width w1 at a downstream
point in the inertial focusing microchannel; and
a pressure/flow source configured to drive a particle-
containing fluid through the inertial focusing microchannel; and
wherein fluid is flowed through the inertial focusing
microchannel by the pressure/flow source at a flow rate such
that the channel Reynolds number, Rc=pUmw1!µ, is larger than
1, wherein the fluid has density p, maximum velocity Um, and
viscosityµ.
App. Br. 16 ( Claims Appendix) ( emphasis added).
The Examiner sets forth the rejection of claims 1-16 and 18-21 under
35 U.S.C. § 103(a) as unpatentable over Crenshaw et al. (US 2009/0142846
Al, published June 4, 2009) in the Final Office Action entered October 30,
2015 ("Final Act."), and maintains the rejection in the Examiner's Answer
entered August 2, 2016 ("Ans.").
DISCUSSION
Upon consideration of the evidence relied upon in this appeal and
each of Appellants' timely contentions2, we affirm the Examiner's rejection
2 We do not consider any new argument Appellants raise in the Reply Brief
that could have been raised in the Appeal Brief. 37 C.F.R. § 4I.37(c)(l)(iv);
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of claims 1-16 and 18-21 under 35 U.S.C. § 103(a) for the reasons set forth
in the Final Action, the Answer, and below.
We review appealed rejections for reversible error based on the
arguments and evidence Appellants provide for each ground of rejection
Appellants contest. 37 C.F.R. § 4I.37(c)(l)(iv); Ex parte Frye, 94 USPQ2d
1072, 1075 (BPAI 2010) (precedential) (cited with approval in In re Jung,
637 F.3d 1356, 1365 (Fed. Cir. 2011) (explaining that even if the examiner
had failed to make a prima facie case, "it has long been the Board's practice
to require an applicant to identify the alleged error in the examiner's
rejections")).
For purposes of this appeal, we address separately argued claims, and
the remaining claims stand or fall with the argued claims, consistent with 3 7
C.F.R. § 4I.37(c)(l)(iv).
Claims 1, 3-5, 9, 12, 15, and 16
Appellants present arguments directed to independent claims 1 and
16, which Appellants argue together, and Appellants do not provide
arguments as to the separate patentability of claims 3-5, 9, 12, and 15. App.
Br. 6-11. We accordingly select claim 1 as representative, and decide the
appeal as to claims 1, 3-5, 9, 12, 15, and 16 based on claim 1 alone. 37
C.F.R. § 4I.37(c)(l)(iv).
Appellants do not dispute the Examiner's finding that Crenshaw
discloses a particle focusing system comprising a substrate, an inlet disposed
in the substrate, an inertial focusing microchannel disposed in the substrate
37 C.F.R. § 41.41 (b )(2) (arguments raised for the first time in the Reply
Brief that could have been raised in the Appeal Brief will not be considered
by the Board unless good cause is shown).
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and connected to the inlet, and a pressure/flow source. Compare Final Act.
3-5, with App. Br. 6-11. Rather, Appellants present the arguments
discussed below, which we determine are unpersuasive of reversible error in
the Examiner's rejection, for reasons that follow.
Appellants argue that Crenshaw does not disclose a system that "uses
a fluid that contains ... suspended particles having a diameter greater than 1
µm." App. Br. 7. Appellants contend that the "core teachings" of Crenshaw
are directed to a microfluidic device that relies on dispersion or diffusion-
based manipulation of "chemical reagents," which Appellants assert are
molecules, rather than particles. Id. Appellants argue that although the
applications of Crenshaw' s system described in the reference include
"clinical diagnostics for neo-natal care e.g., (blood enzyme diagnostics with
microliter samples)," Crenshaw does not "talk[] about actual red blood cells
(RBCs) or other cells being delivered or flowed within the microfluidic
device." App. Br. 8. Appellants further contend that although Crenshaw
also discloses that the system described in the reference can be used for cell-
based assays and flow cytometry applications, Crenshaw "does not then
further state that cells are run through the device as part of the assay." Id.
Appellants assert that "reagents could be flowed through the device to
control dispersion or mix reagents and then exposed to cells subsequently"
or "[c]ells could be immobile within the microfluidic device and may not be
carried within the fluid." Id.
Crenshaw discloses a system for controlling the dispersion of reagents
within fluid streams that flow through microfluidic channels in a
microfluidic chip. ,r,r 2, 7, 13. Crenshaw discloses that "[a]s used herein,
the term 'reagent' generally means any flowable composition or chemistry."
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,r 144. Crenshaw, therefore, does not limit the "reagents" described in the
reference to molecules, as Appellants assert. Furthermore, one of ordinary
skill in the art would have understood at the time of Appellants' invention
that flow cytometry and cell-based assays are used to detect and measure
physical and chemical characteristics of whole cells.
Thus, although Crenshaw's disclosure that the system described in the
reference can be used for cell-based assays and flow cytometry applications
may have suggested to one of ordinary skill in the art that cells are not "run
through" the device as Appellants assert, this disclosure nonetheless also
would have suggested use of fluid streams containing whole cells in
Crenshaw's system to conduct cell-bases assays and flow cytometry
analyses. KSR Int'! Co. v. Teleflex Inc., 550 U.S. 398,418 (2007) ([A]n
obviousness analysis "need not seek out precise teachings directed to the
specific subject matter of the challenged claim, for [an examiner] can take
account of the inferences and creative steps that a person of ordinary skill in
the art would employ."); see also In re Preda, 401 F.2d 825, 826 (CCPA
1968) ("[I]t is proper to take into account not only specific teachings of the
reference but also the inferences which one skilled in the art would
reasonably be expected to draw therefrom.").
Appellants do not dispute the Examiner's finding that red blood cells
have a diameter of 6-8 µm. Compare Final Act. 4, with App. Br. 6-11.
Thus, contrary to Appellants' arguments, Crenshaw's broad definition of
"reagent" as "any flowable composition or chemistry," coupled with
Crenshaw's disclosure that the system can be used for cell-based assays and
flow cytometry applications, would have suggested use of whole cell
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reagents in Crenshaw's system, corresponding to particles having a diameter
greater than 1 µm as recited in claim 1.
Appellants argue that Crenshaw does not disclose or teach flowing a
fluid through an inertial focusing microchannel at a flow rate such that the
channel Reynolds number (Re pUmwilµ) is greater than 1. App. Br. 8.
Appellants contend that "because the device in Crenshaw [] uses diffusion or
dispersion based movement of reagents, it operates at much lower flow
velocities and Reynolds number." Id. Appellants argue that paragraph 125
of Crenshaw discloses a device that includes an expansion channel and an
upstream channel that measures 25 µm wide and 15 µm deep. Id. at 8-10.
Appellants contend that Crenshaw discloses the flow rate of fluid through
this channel was 20 nl/min, which Appellants assert would result in a
Reynolds number of 0.02 "given ... the fact that the solutions being
delivered are aqueous-based." Id. Appellants further argue that "Crenshaw
[] specifically teaches that low Reynolds numbers are necessary so that
changes in concentration of reagents is driven only by diffusion and not any
other process or mechanism." App. Br. 9.
As discussed above, Crenshaw discloses controlling the dispersion of
reagents within fluid streams that flow through channels in a microfluidic
chip. ,r,r 2, 7, 13. Crenshaw explains that a high surface area to volume ratio
in microfluidic channels is "an unavoidable consequence of the
miniaturization of microfluidics," and indicates that due to this high surface
area to volume ratio, adsorption of reagents to channel walls creates
problematic "dispersion artifacts" that do not occur in "more conventional
approaches." ,r,r 2, 401, 402. Crenshaw discloses using large channel
diameters to reduce the ratio of channel surface area to fluid volume, which
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Crenshaw explains, decreases the amount of reagent adsorption at the
channel wall per unit volume. ,r,r 402, 403, 406. Crenshaw emphasizes that
the surface area of all channels exposed to reagents should be "kept
minimal" by using "larger diameters/shorter lengths wherever possible." ,r
407.
Crenshaw describes a microfluidic chip design in which fluid streams
containing reagents flow through a mixing channel followed by a controlled
dispersion element or expansion channel having a cross-sectional area
between approximately 10 to 1000 times the cross-sectional area of the
mixing channel. ,r,r 7, 8; Figs. 55, 56A. Crenshaw discloses driving the
fluid streams with pumps, and indicates that the pumps "are capable of
producing flow rates permitting flow grading between about O and 500
nl/min." ,r,r 11, 152.
One of ordinary skill in the art seeking to develop a microfluidic chip
as disclosed in Crenshaw would have adjusted the flow rate of fluid through
the mixing channel and dispersion element in the chip to a desired level
within the range of O and 500 nl/min disclosed in Crenshaw. One of
ordinary skill in the art also would have adjusted the diameter of both the
mixing and expansion channels in the chip to achieve a cross-sectional area
of the channels (within the range of an expansion channel cross-sectional
area 10 to 1000 times greater than the cross-sectional area of the mixing
channel) that would decrease, to a desired extent, the adsorption of reagents
to the channel walls.
The Reynolds number of the inertial focusing microchannel recited in
claim 1 is determined, in part, by the flow rate and side wall width w1.
Therefore, when adjusting the flow rate, and the mixing and expansion
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channel widths in Crenshaw's chip, one of ordinary skill in the art also
would have adjusted the channel Reynolds number. Consequently, when
seeking to control the adsorption of reagents to the walls of the channels in
Crenshaw' s chip by adjusting the channel widths, one of ordinary skill in the
art would have arrived at a suitable channel Reynolds number, such as that
recited in claim 1, through nothing more than routine experimentation. In re
Applied Materials, Inc., 692 F.3d 1289, 1297 (Fed. Cir. 2012) ("A
recognition in the prior art that a property [ or a result] is affected by the
variable is sufficient to find the variable result-effective."); In re Boesch,
617 F.2d 272, 276 (CCPA 1980) ("[D]iscovery of an optimum value of a
result effective variable in a known process is ordinarily within the skill of
the art.").
Although Appellants argue that Crenshaw explicitly discloses that
"low" Reynolds numbers are necessary so that changes in concentration of
reagents are driven only by diffusion and not by any other process or
mechanism, we find no disclosure in Crenshaw explaining what is meant,
quantitatively, by "low" Reynolds numbers, and Appellants do not direct us
to any such disclosure. App. Br. 9. Nor do we find any other evidence on
this appeal record establishing that one of ordinary skill in the art would
have interpreted the "low" Reynolds numbers discussed in Crenshaw to
mean a channel Reynolds number greater than 1 as recited in claim 1.
Although Appellants also argue that dimensions of the upstream
channel and flow rate described in paragraph 125 of Crenshaw would result
in a Reynolds number of 0.02, Crenshaw's disclosures are not limited to the
channel dimensions (25 µm wide and 15 µm deep) and flow rate (20 nl/min)
set forth in paragraph 125. Rather, as discussed above, Crenshaw broadly
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discloses that the pumps in Crenshaw' s system "are capable of producing
flow rates permitting flow grading between about O and 500 nl/min."
Crenshaw further discloses that channels in microfluidic chips typically have
cross-sectional dimensions of about 1 µm to about 500 µm, and discloses
that the cross-sectional area of the expansion channel should be
approximately 10 to 1000 times the cross-sectional area of the mixing
channel. ,r,r 8, 140. Accordingly, Crenshaw's disclosures as a whole would
have suggested a channel Reynolds number much greater than 0.02, such as
a channel Reynolds number larger than 1, as recited in claim 1. Applied
Materials, 692 F.3d at 1298 ("A reference must be considered for everything
that it teaches, not simply the described invention or a preferred
embodiment.").
Although Appellants assert that Crenshaw "seems to indicate that the
flow rate range of O to 500 nl/min is what the pumps are capable of; not the
flow rate that is actually run through the device," this distinction lacks a
meaningful difference in the context of this appeal. Crenshaw' s disclosure
that the pumps are capable of a flow rate of O to 500 nl/min would have
suggested use of any flow rate within this range to one of ordinary skill in
the art at the time of Appellants' invention.
Because Appellants do not provide any evidence establishing the
criticality of the channel Reynolds number range recited in claim 1 (App. Br.
6-11 ), Appellants' arguments are unpersuasive of reversible error. In re
Woodruff, 919 F.2d 1575, 1578 (Fed. Cir. 1990) (indicating that in cases in
which the difference between the claimed invention and the prior art is some
range or other variable within the claims, the applicant must show that the
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particular range is critical, generally by showing that the claimed range
achieves unexpected results relative to the prior art range.).
Appellants argue that their invention is directed to a system and
method for particle focusing, and does not concern creating reagent
gradients in a microfluidic device as disclosed in Crenshaw. App. Br. 11.
Appellants contend that "expander/reducer zones are used [in Crenshaw] as
a sort of filter to filter out high-frequency fluid gradients," and a "person
having ordinary skill in the art, however, would not look to utilize
expander/reducer zones ( which address reagent concentration gradients) for
focusing of particles in a fluid as the two problems are entirely unrelated to
one another." Id.
It is well established that "[i]n determining whether the subject matter
of a patent claim is obvious, neither the particular motivation nor the avowed
purpose of the patentee controls." KSR Int'! Co. v. Teleflex Inc., 550 U.S.
398, 419 (2007). Accordingly, regardless of whether one of ordinary skill in
the art would have utilized expander/reducer zones for focusing particles in a
fluid based on Crenshaw's disclosures, one of ordinary skill in the art
nonetheless would have adjusted the widths of mixing and expansion
channels in a microfluidic chip as disclosed in Crenshaw to control
dispersion artifacts caused by adsorption of reagents to channel walls in the
chip.
We accordingly sustain the Examiner's rejection of claims 1, 3-5, 9,
12, 15, and 16 under 35 U.S.C. § 103(a).
Claim 2
Independent claim 2 recites a particle analyzing system that
comprises, in part, an inertial focusing microchannel and a particle analyzer
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disposed adjacent a distal end of the inertial focusing microchannel and
configured to analyze particles in the distal end of the inertial focusing
microchannel.
Appellants argue that although Crenshaw discloses an analysis
channel including an analysis region in which confocal optics are used to
measure signals from fluid streams containing reagents, "[t]here is nothing
to suggest that the confocal optics can be used to analyze discrete particles
as opposed to a reacted fluid streamline that continuously flows through the
device." Reply Br. 4; see also App. Br. 11.
We find no definition or limiting description of a "particle analyzer"
in Appellants' Specification, and Appellants do not direct us to any such
disclosure. We therefore interpret this phrase according to its plain and
ordinary meaning as a device that performs any type of examination of
particles in order to understand their nature or determine their essential
features. 3 In re ICON Health and Fitness, Inc., 496 F.3d 1374, 1379 (Fed.
Cir. 2007) (During prosecution of patent applications, "the PTO must give
claims their broadest reasonable construction consistent with the
specification .... Therefore, we look to the specification to see if it provides
a definition for claim terms, but otherwise apply a broad interpretation.").
One of ordinary skill in the art would have understood that confocal
optics as disclosed in Crenshaw could be used to image or examine particles
to understand their nature, 4 and Appellants do not provide any evidence to
support their implicit assertion to the contrary. It is well-established that
3 See, e.g., https://www.merriam-webster.com/ dictionary /analysis.
4 See, e.g., https ://www .microscopyu.com/techniques/ confocal/introductory-
confocal-concepts.
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unsupported attorney arguments cannot take the place of evidence necessary
to resolve a disputed question of fact. Icon Health & Fitness, Inc. v. Strava,
Inc., 849 F.3d 1034, 1043 (Fed. Cir. 2017) ("[a]ttomey argument is not
evidence" and cannot rebut other admitted evidence). Accordingly, the
"particle analyzer" recited in claim 2 does not exclude confocal optics as
disclosed in Crenshaw.
We accordingly sustain the Examiner's rejection of claim 2 under 35
U.S.C. § 103(a).
Claims 6 and 11
Claim 6 depends (indirectly) from claim 1 and recites that the first
expansion and the second expansion have different shapes. Claim 11
depends (indirectly) from claim 1 and recites that at least two of the
expansions have different shapes.
Appellants argue that Crenshaw does not disclose first and second
expansions with different shapes. App. Br. 11.
As discussed above, Crenshaw discloses including an expansion
channel (second expansion) in the microfluidic chip described in the
reference. ,r,r 7, 8; Fig. 7 A. Crenshaw also discloses "placing small
outpockets along the wall of the microfluidic channel," and Crenshaw
explains that "[ o ]utpockets can be considered as small expansion channels
placed in series." ,r 121; Fig. 7B. Although Crenshaw may not explicitly
disclose an embodiment of Crenshaw's microfluidic chip that includes both
outpockets and an expansion channel, one of ordinary skill in the art
nonetheless would have understood that both types of expansions could be
included in Crenshaw's chip to decrease the amount of reagent adsorbed to
channel walls to a desired extent. KSR, 550 U.S. at 417 (quoting Sakraida v.
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Ag Pro, Inc., 425 U.S. 273, 282 (1976) ("[W]hen a patent 'simply arranges
old elements with each performing the same function it had been known to
perform' and yields no more than one would expect from such an
arrangement, the combination is obvious.").
Accordingly, contrary to Appellants' arguments, because Crenshaw
explicitly discloses that the outpockets (first expansion) have a "small" size
relative to the expansion channels (second expansion), Crenshaw would
have suggested first and second expansions having different shapes, as
recited in claims 6 and 11, to one of ordinary skill in the art at the time of
Appellants' invention.
We accordingly sustain the Examiner's rejection of claims 6 and 11
under 35 U.S.C. § 103(a).
Claims 8 and 21
Claim 8 depends (indirectly) from claim 1 and recites, in part, that the
first expansion(s) are axially shorter than the second expansion(s). Claim 21
depends (indirectly) from independent claim 16 and recites, in part, that the
first expansion(s) are axially shorter than the second expansion(s).
Appellants argue that "Crenshaw [] does not disclose having first and
second sections of [a] microchannel with a first section having expansion( s)
that are axially shorter than expansion(s) in the second section." App. Br.
11-12. Appellants also argue that the Examiner's rejection of claim 21
"lacks any foundation or basis." App. Br. 11.
As discussed above, however, Crenshaw would have suggested
including both outpockets and an expansion channel in Crenshaw's
microfluidic chip to decreases the amount of reagent adsorbed to channel
walls to a desired extent. As also discussed above, Crenshaw explicitly
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discloses that the outpockets have a "small" size relative to the expansion
channel (first expansion). Crenshaw further illustrates outpockets having
dimensions that are smaller than the corresponding dimensions of an
expansion channel, including a shorter axial length. Compare Fig. 7 A, with
Fig. 7B.
Thus, contrary to Appellants' arguments, Crenshaw would have
suggested a first expansion ( outpocket) that is axially shorter than a second
expansion ( expansion channel) as recited in claims 8 and 21.
We accordingly sustain the Examiner's rejection of claims 8 and 21
under 35 U.S.C. § 103(a).
Claim 7
Claim 7 depends (indirectly) from claim 1 and recites that each
expansion has a shape selected from the group consisting of trapezoidal,
triangular, rounded, and rectangular.
Citing to paragraph 413 of Crenshaw, the Examiner finds that
Crenshaw discloses an expansion channel having a square cross-section.
Final Act. 6.
Appellants argue that although paragraph 413 of Crenshaw discloses a
detection area that can be circular, elongated, oval, or rectangular, the
"detection area" is a small area located inside the analysis channel, and "is
not the shape of the analysis channel." App. Br. 12.
In response to Appellants' arguments, the Examiner finds in the
Answer that Figure 56B of Crenshaw illustrates square cross-section B-B of
analysis channel AC ( an expansion channel), which "reads on" the
rectangular cross-section recited in claim 7. Ans. 4--5. Supporting the
Examiner's position, Crenshaw discloses that cross-section B-B of analysis
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channel AC (an expansion channel as shown in Figure 56A) illustrated in
Figure 56B has a height approximately equal to its width. ,r 412. Crenshaw
thus indicates that analysis channel AC has a square shape, which is a
rectangle, as recited in claim 7.
We accordingly sustain the Examiner's rejection of claim 7 under 35
U.S.C. § 103(a).
Claim 10
Claim 10 depends (indirectly) from claim 1 and recites that at least
two expansions are axially separated from respective next expansions by
different axial distances.
Appellants argue that Figures 7 A and 7B of Crenshaw do not disclose
"at least two expansion regions that are separated from the next expansion
regions by different axial distances" because Figure 7 A illustrates a single
expansion and Figure 7B illustrates a plurality of outpockets that are
separated by the same axial distance. App. Br. 12.
As discussed above, however, Crenshaw discloses that minimizing the
surface area of all channels exposed to reagents decreases the degree to
which reagents adsorb to the channel walls. Crenshaw further discloses that
one way to minimize the channel surface area is by "making channels as
short as practicable." ,r 407. Thus, by disclosing that the channel length
affects the degree to which reagents adsorb to the channel walls, Crenshaw
recognizes that channel length is a result-effective variable. In re Applied
Materials, 692 F.3d at 1297.
Therefore, although Crenshaw does not explicitly disclose two
expansions axially separated from respective next expansions by different
axial distances, one of ordinary skill in the art nonetheless would have
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adjusted the length of the channels in Crenshaw's system-including the
length of the channels between individual expansions (axial distance
between expansions }-to decrease, to a desired extent, the degree to which
reagents adsorb to the channel walls. In so doing, one of ordinary skill in the
art would have arrived at optimal lengths for the channels in Crenshaw' s
system, including the length of the channels between the expansions, such as
channel lengths in which two expansions are axially separated from
respective next expansions by different axial distances, as recited in claim
10, through nothing more than routine experimentation. Boesch, 617 F .2d at
276 (CCPA 1980).
Because Appellants do not argue, much less establish, the criticality of
the relative axial separation distances recited in claim 10 (App. Br. 12), we
sustain the Examiner's rejection of claim 10 under 35 U.S.C. § 103(a).
Woodruff, 919 F.2d at 1578.
Claim 13
Claim 13 depends from claim 1 and recites that the inertial focusing
microchannel has a substantially rectangular cross-section having a height
and a width, and a ratio of height to width is approximately 5:4 to 4:1.
Appellants argue that paragraph 413 of Crenshaw, relied on by the
Examiner in rejecting claim 13, discusses the embodiment illustrated in
Figure 56B of Crenshaw, which illustrates square-shaped channels, rather
than channels shaped as recited in claim 13. App. Br. 13. Appellants assert
that paragraph 412 of Crenshaw "discloses how the height and width should
be equal to one another for a ratio of 1: 1." Id. Appellants contend that
although Crenshaw discloses different shapes for detection area, such as
circular, elongated, oval, or rectangular, the "detection area" refers to the
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small, center region of the analysis channel where detection occurs, rather
than the cross-sectional shape of the channel itself. Id.
We note initially that the "inertial focusing microchannel" recited in
claim 1 consists essentially of a pair of side walls separated by a width w1,
where one of the side walls includes at least one expansion extending
outwardly and having a width w2, so that w2>w1. Claim 1 recites that the at
least one expansion returns to a width w1 at a downstream point in the
inertial focusing microchannel. Thus, the "inertial focusing microchannel"
recited in claim 1 includes at least one section having relatively larger width
w2 ( expansion section) positioned between two sections that each have
relatively smaller widths w1. Because claim 13 recites that the inertial
focusing microchannel has a substantially rectangular cross-section having a
height and a width, and a ratio of height to width is approximately 5:4 to 4:1,
claim 13 requires only a single section of the microchannel to have the
recited height to width ratio ("a ratio of height to width'), such as the
expansion section.
As the Examiner correctly finds (Ans. 5), Crenshaw discloses that
"[ e ]xpansion channels can be shaped and sized for introducing a desired
amount of dispersion over a predetermined spatial frequency." ,r 119.
Crenshaw further discloses that "the expansion channels can also be made
narrow and deep for increasing the rate of mix via lateral diffusion in the
expansion channel." ,r 124. Thus, by disclosing that the shape of the
expansion channels affects the amount of dispersion, and the mix rate, of
reagents in the expansion channels, Crenshaw recognizes that the expansion
channel shape is a result-effective variable. Applied Materials, 692 F.3d at
1297.
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Therefore, one of ordinary skill in the art would have adjusted the
shape of the expansion channels in Crenshaw's system to achieve a desired
degree of reagent dispersion, and a desired reagent mix rate, in the
expansion channels. In so doing, one of ordinary skill in the art would have
arrived, through routine experimentation, at an optimum height to width
ratio for the expansion channels, such as a height to width of approximately
5 :4 to 4: 1, as recited in claim 13, through nothing more than routine
experimentation. Boesch, 617 F.2d at 276 (CCPA 1980).
Because Appellants do not argue, much less establish, the criticality of
the height to width ratio recited in claim 13 (App. Br. 13), we sustain the
Examiner's rejection of claim 13 under 35 U.S.C. § 103(a).
Claim 14
Claim 14 depends from claim 1 and recites that the system further
comprise "a downstream expanding region having a side wall, wherein the
side wall has a stepped surface."
Appellants argue that the "stepped surface" recited in claim 14 "refers
to multiple steps which can be seen in FIGS. 1 lC and 1 lD of the
Application." App. Br. 13. Appellants contend that Crenshaw "does not
disclose this feature." Id.
Appellants' Specification indicates that the system of Appellants'
invention may include an expanding region having a side wall that may have
a curved or stepped surface. ,r 8. Appellants' Specification also indicates
that "[e]xpansions with steps (Fig. 1 lC and Fig. 1 lD) reduce wall-particle
interactions and result in narrower and more focused particle streams." ,r 81.
Appellants' Figure 11 C appears to illustrate an expansion with a single step,
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Application 13/988,282
while Appellants' Figure 1 lD appears to illustrate an expansion with
multiple steps. We find no further discussion of steps in Appellants'
Specification.
Consistent with these disclosures in Appellants' Specification, and
with Appellants' Figures 1 lC and 1 lD, we interpret "a stepped surface"
recited in claim 14 to be a surface that includes one or more steps. ICON,
496 F.3d at 1379. Therefore, contrary to Appellants' arguments, "a stepped
surface" as recited in claim 14 does not refer only to multiple steps, but also
refers to a single step. Thus, claim 14 does not exclude an expansion
channel as illustrated in Figure 56A of Crenshaw that has a side wall
including a single step. We accordingly sustain the Examiner's rejection of
claim 14 under 35 U.S.C. § 103(a).
Claims 18, 19, and20
Although Appellants present separate arguments for each of claims
18, 19, and 20, Appellants' arguments for these claims are not substantively
distinct from the arguments Appellants provide for claim 1. App. Br. 13-14.
Because we are unpersuaded of reversible error in the Examiner's rejection
of claim 1 for the reasons discussed above, Appellants' position as to these
claims is also unpersuasive of reversible error. We accordingly sustain the
Examiner's rejection of claims 18, 19, and 20 under 35 U.S.C.
§ 103(a).
DECISION
We affirm the Examiner's rejection of claims 1-16 and 18-21 under
35 U.S.C. § 103(a).
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Application 13/988,282
No time period for taking any subsequent action in connection with
this appeal may be extended under 37 C.F.R. § 1.136(a).
AFFIRMED
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