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 .
Continued Examination Under 37 CFR 1.114
A request for continued examination under 37 CFR 1.114, including the fee set forth in 37 CFR 1.17(e), was filed in this application after final rejection. Since this application is eligible for continued examination under 37 CFR 1.114, and the fee set forth in 37 CFR 1.17(e) has been timely paid, the finality of the previous Office action has been withdrawn pursuant to 37 CFR 1.114. Applicant's submission filed on 02/06/2026 has been entered.
Claim Objections
Claim 9 is objected to because of the following informalities:
Claim 9, line 6: “fluidly” should be replaced with –fluidically–;
Claim 9, line 12: “advance” should be replaced with “advancement”;
Claim 9, line 15: –the– should be inserted before “intra-abdominal”.
Appropriate correction is required.
Claim Rejections - 35 USC § 112
The following is a quotation of 35 U.S.C. 112(b):
(b) CONCLUSION.—The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the inventor or a joint inventor regards as the invention.
The following is a quotation of 35 U.S.C. 112 (pre-AIA ), second paragraph:
The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the applicant regards as his invention.
Claims 9, 12, 13, and 20-22 rejected under 35 U.S.C. 112(b) or 35 U.S.C. 112 (pre-AIA ), second paragraph, as being indefinite for failing to particularly point out and distinctly claim the subject matter which the inventor or a joint inventor (or for applications subject to pre-AIA 35 U.S.C. 112, the applicant), regards as the invention.
Claim 9 recites “a location of an interface between the fluid and the gas” in lines 7-8 and “a stabilized, pressure-dependent interface position between the fluid and the gas” in lines 12-13. It is unclear if the location of lines 7-8 and the position of lines 12-13 are the same as, related to, or different from each other. The differences in language suggest that they are different. However, the specification does not create a distinction between the limitations, which suggests that they are the same.
Claims 12, 13, and 20-22 are rejected by virtue of their dependence from claim 9.
Claim 21 recites “the microfluidic device”. Claim 22 recites “the microfluid device”. There are insufficient antecedent bases for these limitations in the claim. For the purposes of examination, the recitations will be interpreted to be “the microfluidic pressure sensor”.
Claim Rejections - 35 USC § 103
In the event the determination of the status of the application as subject to AIA 35 U.S.C. 102 and 103 (or as subject to pre-AIA 35 U.S.C. 102 and 103) is incorrect, any correction of the statutory basis (i.e., changing from AIA to pre-AIA ) for the rejection will not be considered a new ground of rejection if the prior art relied upon, and the rationale supporting the rejection, would be the same under either status.
The following is a quotation of 35 U.S.C. 103 which forms the basis for all obviousness rejections set forth in this Office action:
A patent for a claimed invention may not be obtained, notwithstanding that the claimed invention is not identically disclosed as set forth in section 102, if the differences between the claimed invention and the prior art are such that the claimed invention as a whole would have been obvious before the effective filing date of the claimed invention to a person having ordinary skill in the art to which the claimed invention pertains. Patentability shall not be negated by the manner in which the invention was made.
The factual inquiries for establishing a background for determining obviousness under 35 U.S.C. 103 are summarized as follows:
1. Determining the scope and contents of the prior art.
2. Ascertaining the differences between the prior art and the claims at issue.
3. Resolving the level of ordinary skill in the pertinent art.
4. Considering objective evidence present in the application indicating obviousness or nonobviousness.
This application currently names joint inventors. In considering patentability of the claims the examiner presumes that the subject matter of the various claims was commonly owned as of the effective filing date of the claimed invention(s) absent any evidence to the contrary. Applicant is advised of the obligation under 37 CFR 1.56 to point out the inventor and effective filing dates of each claim that was not commonly owned as of the effective filing date of the later invention in order for the examiner to consider the applicability of 35 U.S.C. 102(b)(2)(C) for any potential 35 U.S.C. 102(a)(2) prior art against the later invention.
Claims 9 and 13 are rejected under 35 U.S.C. 103 as being unpatentable over US 2016/0007851 A1 (Araci) (previously cited) in view of US 2010/0222802 A1 (Gillespie, Jr.) (previously cited) and US 2019/0231236 A1 (Heikenfeld)
With regards to claim 9, Araci teaches a method, comprising: inserting a microfluidic pressure sensor into an organ (¶ [0025] and Claim 22 disclose implanting the sensor into an organ, including a bladder), the microfluidic pressure sensor comprising a fluid and a gas predisposed in an internal cavity of the microfluidic pressure sensor (Fig. 1 and ¶ [0028] depict the a microfluidic channel 112 connected to a reservoir 114, the microfluidic channel open to aqueous intraocular liquid); and measuring bodily pressure based on a location of fluid within an internal cavity (¶¶ [0028]-[0029], [0032] disclose measuring intraocular pressure based on a location of the gas-fluid interface 116).
The above embodiment is silent with regards to whether the microfluidic pressure sensor comprising a fluid and a gas predisposed and sealed within the microfluidic pressure sensor, the microfluidic pressure sensor comprising a deformable reservoir and a channel fluidly connected to the reservoir, wherein an external pressure applied to the deformable reservoir causes the fluid to advance toward the channel, wherein, upon reduction of external pressure, the fluid retreats towards the reservoir.
In a related embodiment, Araci teaches a microfluidic pressure sensor comprising a fluid and a gas predisposed and sealed in the microfluidic pressure sensor (Fig. 9 and ¶ [0035] disclosed a fluid filled reservoir 930 connected to a small cross section channel 940 for detecting changes in intraocular pressure, wherein changes in pressure cause shifts of fluid volume and movement of the liquid-air interface; Fig. 9 depict the fluid and gas being sealed within the IOP sensor 910), the microfluidic pressure sensor comprising a deformable reservoir and a channel fluidly connected to the reservoir (Fig. 9 and ¶ [0035] discloses a flexible thin membrane 920 covering a fluid filled reservoir 930 connected to a small cross section channel 940, wherein the flexible thin membrane 920 makes the reservoir 930 deformable), wherein an external pressure applied to the deformable reservoir causes the fluid to advance toward the channel (Fig. 9 and ¶ [0035]), wherein, upon reduction of external pressure, the fluid retreats towards the reservoir(The Examiner asserts that the IOP sensor 910 of Fig. 9 and ¶ [0035] is sized and shaped such that reduction of the external pressure would cause the fluid to retreat towards the reservoir and enabling repeatable positioning of the interface. Also see analogous ¶ [0028] which indicates that increasing and decreasing the pressure causes a shift of the fluid interface towards opposite directions). It would have been obvious for one of ordinary skill in the art before the effective filing date of the claimed invention to have substituted the microfluidic pressure sensor of Fig. 1 of Araci with the embodiment shown in Fig. 9 of Araci. Because both elements are capable of being used as pressure sensors, it would have been the simple substitution of one known equivalent element for another to obtain predictable results.
The above combination is silent with regards to measuring, using ultrasonic imaging, bodily pressure based on a location of an interface between the fluid and the gas within the internal cavity.
In a related embodiment, Araci teaches measuring, using ultrasonic imaging, bodily pressure based on a location of an interface between the fluid and the gas within the channel (¶¶ [0010], [0051] discloses pressure sensing using an ultrasound imaging device for detection of the gas liquid interface through the skin tissue). It would have been obvious for one of ordinary skill in the art before the effective filing date of the claimed invention to have substituted the imaging system of the above combination with the ultrasound imaging device as taught by Araci. Because both elements are capable of being used for imaging a gas-fluid interface, it would have been the simple substitution of one known equivalent element for another to obtain predictable results. Additionally or alternatively, the motivation would have been to allow interrogation of the pressure device through skin tissue (¶ [0010] of Araci).
Although Araci teaches monitoring organs (¶ [0025] disclose implanting the sensor into a variety of organs), the above combination is silent regarding whether the microfluidic pressure sensor is inserted into an abdominal cavity via a minimally invasive injection needle so as to monitor an intra-abdominal pressure.
In the same field of endeavor of implantable pressure sensors, Gillespie, Jr. teaches or suggest a pressure sensor is inserted into an abdominal cavity (¶ [0153] discloses implanting a pressure sensing device into an abdominal cavity) via a minimally invasive injection needle (Fig. 9, 9A and ¶¶ [0170]-[0171] depict inserting a implant via a needle, wherein the needle and components are sized to be minimally invasive) so as to monitor an intra-abdominal pressure (the Examiner notes that a pressure sensor inserted into an abdominal cavity necessarily monitors pressure within the abdominal cavity). It would have been obvious for one of ordinary skill in the art before the effective filing date of the claimed invention to have modified the above combination of Araci to incorporate that the pressure sensor is inserted into an abdominal cavity via a minimally invasive injection needle so as to monitor an intra-abdominal pressure as taught by Gillespie, Jr. The motivation would have been to acquire pressure sensors readings relevant to the abdomen, thereby providing a more complete diagnostic analysis of the patient.
The above combination is silent regarding whether the channel is hydrophobic, the hydrophobic microchannel resists pressure-driven advance of the fluid to stabilize the interface between the fluid and the gas, wherein the hydrophobicity allows for fluid to retreat due to capillary action, thereby enabling repeatable positioning of the interface.
In the same field of transporting fluids within a channel, Heikenfeld teaches a hydrophobic channel, wherein the hydrophobic microchannel resists pressure-driven advance of the fluid to stabilize the interface between the fluid and the gas, wherein the hydrophobicity allows for fluid to retreat due to capillary action, thereby enabling repeatable positioning of the interface (Figs.11A-11C and ¶¶ [0054]-[0055] depict a channel 1140 with a hydrophobic coating which causes a convex meniscus to form. The Examiner notes that the hydrophobicity necessarily results in a stabilized meniscus and/or interface capable of repeatedly advancing and retreating within the channel–see at least ¶ [0023] of the Applicant’s published application). It would have been obvious for one of ordinary skill in the art before the effective filing date of the claimed invention to have modified the channel of the above combination to incorporate that it is hydrophobic as taught by Heikenfeld. The motivation would have been to prevent the fluid from sticking to the walls, which improves movement of the liquid-air interface in response to pressure changes. Additionally or alternatively, it would have been the simple substitution of one known equivalent element for forming the channels with another to obtain predictable results.
With regards to claim 13, the above combination teaches or suggests measuring the intra-abdominal pressure based on the location of the interface between the fluid and the gas within the channel further comprises: converting the measured location of the interface between the fluid and the gas in the hydrophobic channel of the sensor to a pressure measurement based on a correlation function that characterizes previously measured pressures and fluid levels (¶ [0029] of Araci discloses intra-ocular pressure readout based on the liquid-air/gas interface position; ¶ [0032] of Araci and Fig. 4 depict a calibration curve obtained by previous measurements for pressure calculation) .
Claim 12 is rejected under 35 U.S.C. 103 as being unpatentable over Araci in view of Gillespie, Jr. and Heikenfeld, as applied to claim 9 above, and further in view of US 2019/0254633 A1 (Anderson) (previously cited).
With regards to claim 12, the above combination teaches or suggests identifying the location of the interface between the fluid and the gas within the internal cavity of the sensor (¶¶ [0010], [0029], [0035] of Araci depict identifying the location of the liquid-air interface), the sensor being in an abdominal cavity (see the above rejection of claim 9 regarding the combination in view of Gillespie, Jr.)
Although the above combination teaches or suggests the use of an ultrasound imaging device to identify the position of the gas liquid interface (¶¶ [0010], [0051] of Araci), the above combination is silent with regards to directing an ultrasound probe at the body; displaying, based on the image data, the microfluidic pressure sensor in the abdominal cavity.
In a system relevant to the problem of imaging an element using ultrasound, Anderson teaches directing an ultrasound probe at the body (Abstract and ¶ [0004] depicts an ultrasound transducer used for imaging a body cavity); displaying, based on the ultrasonic imaging, the bodily cavity (Abstract and ¶ [0004] depicts generating a sonographic image of the body cavity and fluids in the body cavity). It would have been obvious for one of ordinary skill in the art before the effective filing date of the claimed invention to have modified the ultrasound imaging of the liquid-air interface of the above combination, based on the teachings of Anderson, to incorporate directing an ultrasound probe at the abdominal cavity; displaying, based on the image data, the microfluidic pressure sensor in the abdominal cavity. The motivation would have been to provide the necessary hardware and images for identifying the liquid-air interface.
Claims 20-22 are rejected under 35 U.S.C. 103 as being unpatentable over Araci in view of Gillespie, Jr. and Heikenfeld, as applied to claim 9 above, and further in view of US 10,684,184 B2 (Wade) and US 2020/0305741 (Gunn).
With regards to claim 20, the above combination teaches or suggests inserting the microfluidic pressure sensor into the abdominal cavity (¶ [0153] of Gillespie Jr. discloses implanting a pressure sensing device into an abdominal cavity).
The above combination is silent regarding injecting the fluid into the deformable reservoir.
In a system relevant to the problem of making a pressure sensor, Wade teaches injecting fluid into deformable reservoir (Col. 16, line 65 to Col. 17, line 20 and Fig. 16 depict a sidewall 65 and/or other portions of the pressure sensor assembly being formed of a pierceable material and/or including a septum 62 formed of a pierceable material that facilitates receiving a needle of a syringe 64 configured to provide a gel or liquid material to the cavity 52 to form the force transmitting member 20, wherein the pierceable material may re-seal on its own once the needle or syringe is removed). It would have been obvious for one of ordinary skill in the art before the effective filing date of the claimed invention to have modified the pressure sensor of the above combination to incorporate injecting the fluid into the deformable reservoir using a re-sealable pierceable material as taught by Wade. It would have been the simple substitution of one known equivalent method for filling the reservoir for another to obtain predictable results.
The above combination is silent regarding whether the injection is performed before inserting the microfluidic pressure sensor into the body
In a system relevant to the problem of making a pressure sensor, Gunn teaches filling a reservoir before inserting the microfluidic pressure sensor into the body (¶ [0158] discloses filling a depression with a pressure-transmitting gel prior to insertion into the eye). It would have been obvious for one of ordinary skill in the art before the effective filing date of the claimed invention to have modified the pressure sensor of the above combination to incorporate filling the reservoir before inserting the pressure sensor into the eye as taught by Gunn. The motivation would have been to improve the ease of manufacturing the pressure sensor by doing it outside the body. Additionally or alternatively, it would have been the simple substitution of one known method for producing a pressure sensor with another to obtain predictable results.
With regards to claim 21, the above combination teaches or suggests the injecting further comprises puncturing a hole into the microfluidic device to insert the fluid (Col. 16, line 65 to Col. 17, line 20 and Fig. 16 of Wade depict puncturing the pierceable material using a needle).
With regards to claim 22, the above combination teaches or suggests the microfluid device self-seals the hole created when the fluid is injected into the deformable reservoir (Col. 16, line 65 to Col. 17, line 20 and Fig. 16 of Wade depict the pierceable material may re-seal on its own once the needle or syringe is removed).
Response to Arguments
Claim Objections
There are new claim objections necessitated by the claim amendments filed 02/06/2026.
Claim Rejections – 35 U.S.C. §112
There are new grounds of claim rejections under 35 U.S.C. §112(b) necessitated by the claim amendments filed 02/06/2026.
Claim Rejections – 35 U.S.C. §103
There are new grounds of rejections necessitated by the claim amendments filed 02/06/2026. To the extent that the Applicant’s arguments are applicable to the current prior art rejections, the Examiner makes the following comments.
Applicant's arguments filed 02/06/2026 have been fully considered but they are not persuasive.
Applicant asserts that the proposed combination relies on impermissible hindsight because Araci teaches away from using hydrophobic microchannels because paragraph [0042] indicates that hydrophobic channel surfaces cause capillary pressure drops that introduce nonlinear behavior in the pressure response, and, in order to eliminate this nonlinear behavior, the channel surfaces should be rendered hydrophilic.
This argument is not persuasive.
MPEP 2145 (X)(D)(1) indicates “A known or obvious composition does not become patentable simply because it has been described as somewhat inferior to some other product for the same use… The court held the claims would have been obvious over the prior art because the reference taught epoxy resin based material was useful for the inventor’s purpose, applicant did not distinguish the claimed epoxy from the prior art epoxy, and applicant asserted no discovery beyond what was known to the art”.
Paragraphs [0038]-[0042] of Araci discuss the sensitivity of the system. Specifically, ¶¶ [0041], [0042] and Fig. 10 depict a circuit of the sensor which considers capillary effects (Δ
P
c
a
p
f
w
and Δ
P
c
a
p
f
w
) of the sensor in relation to its sensitivity. ¶ [0042] teaches that the embodiment of Fig. 10 considers the nonlinear behavior of the capillary effects and indicates the behavior as a diode in the circuit diagram. ¶ [0042] further notes the nonlinear behavior of capillary effects may be eliminated by rendering the channel surfaces hydrophilic. The Examiner notes that the hydrophilic channel surfaces amounts to another embodiment which does not include the non-linear capillary effects denoted by a diode.
Araci merely describes two alternatives for modeling the pressure sensing capabilities of the device, wherein the embodiment with hydrophilic channels may be modeled in a different manner because it does not have non-linear capillary effects. There is no indication within Araci that disparages the use of the hydrophobic channels. Instead, Araci considers the non-linear effects of the hydrophobic channels by modeling the effect as diodes in the circuit diagram of Page 10. Additionally, the above combination of Araci in view of Heikenfeld teaches or suggests a hydrophobic channel which is useful for the applicant’s purpose, applicant did not distinguish the claimed hydrophobic channel from that of the combination of Araci in view of Heikenfeld, and applicant asserted no discovery beyond what was known to the art.
Applicant asserts that Araci and Truckai do not teach the missing functional limitations of “resisting pressure-driven fluid advance using hydrophobicity to stabilize an interface position” or “enabling repeatable positioning of the interface via capillary-driven retreat upon pressure reduction”.
This argument is moot because of the new grounds of rejection is made in view of Heikenfeld. Specifically, Heikenfeld teaches, in Figs.11A-11C and ¶¶ [0054]-[0055], a channel 1140 with a hydrophobic coating which causes a convex meniscus to form, wherein the interface may move forward and backward. Additionally or alternatively, the Examiner notes that the modification of the channels to include hydrophobicity as taught by Heikenfeld necessarily results in a stabilized meniscus and/or interface capable of repeatedly advancing and retreating within the channel–see at least ¶ [0023] of the Applicant’s published application. There is no teaching or suggestion within the specification that the resistance to pressure-driven fluid advancement and the repeatable positioning stems from other structural features.
Applicant asserts that the proposed combination relies on impermissible hindsight because one would need to:
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Applicant’s arguments regarding (1) and (2) are not persuasive for the reasons listed above. Specifically, Araci does not teach away from the use of hydrophobic channels.
Applicant’s arguments regarding (3) and (4) are not persuasive because the above combination in view of Heikenfeld teaches or suggests the limitations. Additionally, in response to applicant's argument that the examiner's conclusion of obviousness is based upon improper hindsight reasoning, it must be recognized that any judgment on obviousness is in a sense necessarily a reconstruction based upon hindsight reasoning. But so long as it takes into account only knowledge which was within the level of ordinary skill at the time the claimed invention was made, and does not include knowledge gleaned only from the applicant's disclosure, such a reconstruction is proper. See In re McLaughlin, 443 F.2d 1392, 170 USPQ 209 (CCPA 1971). In this case, it would have been obvious for one of ordinary skill in the art before the effective filing date of the claimed invention to have modified the channel of the above combination to incorporate that it is hydrophobic as taught by Heikenfeld. The motivation would have been to prevent the fluid from sticking to the walls, which improves movement of the liquid-air interface in response to pressure changes. Additionally or alternatively, it would have been the simple substitution of one known equivalent element for forming the channels with another to obtain predictable results. Additionally or alternatively, the Examiner notes that the modification of the channels to include hydrophobicity as taught by Heikenfeld necessarily results in a stabilized meniscus and/or interface capable of repeatedly advancing and retreating within the channel–see at least ¶ [0023] of the Applicant’s published application. There is no teaching or suggestion within the specification that the resistance to pressure-driven fluid advancement and the repeatable positioning stems from other structural features.
Conclusion
Any inquiry concerning this communication or earlier communications from the examiner should be directed to SAMUEL C KIM whose telephone number is (571)272-8637. The examiner can normally be reached M-F 8:00 AM - 5:00 PM EST.
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/S.C.K./Examiner, Art Unit 3791
/JACQUELINE CHENG/Supervisory Patent Examiner, Art Unit 3791