DETAILED ACTION
The present application, filed on or after March 16, 2013, is being examined under the first inventor to file provisions of the AIA .
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.
Status of the Claims
Claims 1-22 are pending. Claims 4 and 13-22 are withdrawn. Claims 1-3 and 5-12 are under consideration in this action.
Change in Examiner
The examiner for your application in the USPTO has changed. Examiner Monica Shin can be reached at 571-272-7138.
Election/Restrictions
Applicant’s election without traverse of Group I (claims 1-12) and with traverse for the following species in the reply filed on January 21, 2026 is acknowledged:
Polysaccharide: apple fibers
Wt.% for the conductive hydrogel: 7.7 wt.% of polysaccharide (i.e., the range of 10-30 wt.% of polysaccharide)
Filler: activated carbon black
Crosslinker: citric acid
Polymer: polyvinyl alcohol
Applicant's election with traverse of the above species in the reply filed on January 21, 2026 is acknowledged. Upon further reconsideration, the species of the polysaccharide, filler, crosslinker, and polymer are withdrawn. However, the species election for the range of wt.% of polysaccharide is maintained. The traversal is on the ground(s) that the above species would not be separately classified, and each category of alleged species above may be easily searched together with no undue burden. This is not found persuasive because the structure and mode of action would be different based on the amount of polysaccharide present in the hydrogel, and the species have different issues regarding patentability as discussed further below. The requirement is still deemed proper and is therefore made FINAL.
Claims 4 and 13-22 are withdrawn from further consideration pursuant to 37 CFR 1.142(b) as being drawn to a nonelected invention and species, there being no allowable generic or linking claim. Election was made without traverse with regards to the invention and with traverse with regards to the species in the reply filed on January 21, 2026.
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 1-12 are 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.
Claims 1, 3, 5, 7, and 9 each recite a weight percentage range for various components of the conductive hydrogel, but do not recite what the percentages are based on. In light of the Specification, it is unclear what the percentages are based off of (e.g., based on the total composition, based on particular component(s) of the composition, etc.). Discussed below are the inconsistencies causing indefiniteness in more detail regarding each particular amounts and ranges.
Specifically regarding the percentage of the polysaccharide (claims 1 and 3), first, it is noted that claim 1 allows for the maximum amount being 100 wt.% of polysaccharide. However, as noted in the instant Specification, hydrogels are three-dimensional networks of hydrophilic polymer cross-linked with varying quantities of water (P.G. Pub., para.0003). Thus, the hydrogel cannot be entirely made up of polysaccharide because at the very least, water is a required component. Furthermore, the Examples shown in Table 1 have the polysaccharide + PVA totally 100 wt.%. However, the Examples disclose that borax (crosslinker) was added to prepare the mixture, and in several of the samples in Table 1 that further include a filler, the amount of polysaccharide + PVA + filler exceed 100 wt.% (P.G. Pub., para.0048; Table 1).
Based on the various sample hydrogels made in Table 1, it appears that the claimed ranges of weight percentage of the polysaccharide is not based on the total hydrogel, but rather, based off of the total polymeric components (in the case of the sample in Table 1, polysaccharide + PVA). Thus, for the purposes of examination below, the weight % ranges recited for the polysaccharide components will be interpreted as the weight percent based on the total polymeric components. Relatedly, the weight % range recited for the additional polymer (e.g., PVA) as recited in claim 9 will also be interpreted as the weight percent based on the total polymeric components, consistent with the samples shown in Table 1.
Specifically regarding the amount of filler (claim 5), the Specification first notes that the range of 1 wt.% to 5 wt.% of filler is relative to polysaccharide (P.G. Pub., para.0008). However, in the examples in the Specification, the 1-5 wt.% of the fillers are relative to PVA solid content (P.G. Pub., para.0048; Table 1).
Specifically regarding the amount of crosslinker (claim 7), the Specification appears to note that the amount of 2 wt.% to about 15 wt.% of crosslinker is relative to polysaccharide content (P.G. Pub., para.0008, 0031).
Claims 2, 6, 8, and 10-12 are subsequently rejected as they incorporate at least one of the limitations discussed above and do not remedy the issues discussed above.
Further regarding claim 12, the claim recites the property “wherein the conductive hydrogel exhibits a storage modulus of 15 kPa to 60 kPa over a plurality of alternating low-high shear strain cycles.” The boundaries of this property are unclear because the claim does not provide a discernable boundary on what provides this characteristic to the hydrogel. In particular, the claim merely recites a property without provide any indication about how the property is provided. While it may be known in the art of various ways to provide for a certain storage modulus, to a hydrogel, it is unclear which of those ways are encompassed by the claim (e.g., is it due to the addition of some unrecited component, is it due to adjust of the weight percentage of the components explicitly encompassed by claim 12, etc.) Thus, one of ordinary skill in the art would not be able to draw a clear boundary between what is and is not covered by the claim.
Claim Rejections - 35 USC § 102
The following is a quotation of the appropriate paragraphs of 35 U.S.C. 102 that form the basis for the rejections under this section made in this Office action:
A person shall be entitled to a patent unless –
(a)(1) the claimed invention was patented, described in a printed publication, or in public use, on sale, or otherwise available to the public before the effective filing date of the claimed invention.
Claims 1-3, 5, and 9-11 are rejected under 35 U.S.C. 102(a)(1) as being anticipated by Zhao et al. (Zhao) (ACS Appl. Mater. Interfaces; published 2021).
With regards to Claims 1-3 and 9-11, Zhao discloses multi-functional conductive composite hydrogels fabricated by a simple one-pot method based on poly(vinyl alcohol) (PVA), sodium alginate (reading on polysaccharide), and tannic acid, using borax as a cross-linker (PBST hydrogel). The obtained hydrogel exhibited pH- and sugar-responsiveness, high stretchability, and fast self-healing performance with healing efficiency as high as 93.56% without any external stimulus (abstract). The conductivity of the PBST hydrogel was 2.69 S/m (26.9 mS/cm) (p.11350, col.2, 3.6. Electrical Performance of the PBST Hydrogel).
With regards to the amount of sodium alginate (polysaccharide) in the PBST hydrogel, Zhao discloses that in preparing the PBST hydrogels, sodium alginate was added to a PVA solution (8 wt.%) to form a uniform mixture. After that, tannic acid was introduced into the mixture, and the mixture was adjusted to a pH of 8 with sodium hydroxide. Finally, the desired dosage of borax (0.1 M) was added to obtain the PBST composite hydrogels (labeled as PBSnTy, with x and y representing the amount (%) of sodium alginate and tannic acid added, respectively (p.11346, col.1, 2.2. Preparation of PBST Hydrogels). Zhao discloses a PBS1.5T0.4 (herein abbreviated as PBST), which has a content of sodium alginate of 1.5% (p.11347, col.1, para.2 to col.2, para.1). Thus, sodium alginate makes up about 16 wt.% based on the total polymeric components (sodium alginate + PVA), and the PVA makes up about 84 wt.% based on the total polymeric components (sodium alginate + PVA).
With regards to the stretchability, the instant Specification defines “stretchability” as the length of the conductive hydrogel after stretching divided by the length of the conductive hydrogel prior to stretching, multiplied by 100 to obtain a percentage (P.G. Pub., para.0026). In the present case, Zhao’s Fig. 2(c) shows pictures of manual stretching of the PBST hydrogel (p.11347). The starting length was 1 cm, and the final length after stretching was 30 cm. Thus, the stretchability is 3000%.
With regards to Claim 5, as discussed above the PBST hydrogels comprise tannic acid. Tannic acid is a plant-derived polyphenolic substance containing abundant catechol groups, and it has been widely utilized as a good adhesive material. The obtained hydrogel showed a repeatable self-adhesive ability owing to the presence of tannic acid in the hydrogel network (p.11345, col.1, para.2 to col.2, para.1). Thus, tannic acid reads on a filler.
With regards to the amount of tannic acid (filler), as discussed above, in PBS1.5T0.4, the amount of tannic acid in the PBST hydrogel is 0.4% (p.11347, col.2, para.1). Thus, the amount of filler is about 5 wt.% relative to the PVA solid content.
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 1-3, 5, and 7-11 are rejected under 35 U.S.C. 103 as being unpatentable over Zhao et al. (Zhao) (ACS Appl. Mater. Interfaces; published 2021).
The teachings of Zhao as they apply to Claims 1-3, 5, and 9-11 are set forth above and incorporated herein. Additional relevant teachings of Zhao are set forth herein below.
With regards to Claims 7 and 8, Zhao discloses using borax as a crosslinker (abstract). Zhao discloses that in preparing the PBST hydrogels, sodium alginate was added to a PVA solution (8 wt.%) to form a uniform mixture. After that, tannic acid was introduced into the mixture, and the mixture was adjusted to a pH of 8 with sodium hydroxide. Finally, the desired dosage of borax (0.1 M) was added to obtain the PBST composite hydrogels (p.11346, col.1, 2.2. Preparation of PBST Hydrogels). Zhao discloses a PBS1.5T0.4 (herein abbreviated as PBST), which has a content of sodium alginate of 1.5% (p.11347, col.1, para.2 to col.2, para.1).
With regards to the amount of crosslinker in the hydrogel, it would have been obvious to one of ordinary skill in the art before the effective filing date of the invention to engage in routine experimentation to determine optimal or workable ranges that produce expected results. In the present case, knowing the concentration of borax used as the crosslinker, its function as a crosslinker, and Zhao’s desired mechanical properties of the hydrogel, one of ordinary skill in the art would have found it prima facie obvious and would have been motivated before the effective filing date to engage in routine experimentation to determine the optimal or workable amount of crosslinker based on art recognized factors and parameters, such as the desired mechanical properties of the resulting hydrogel. Where the general conditions of a claim are disclosed in the prior art, it is not inventive to discover the optimum or workable ranges by routine experimentation. In re Aller, 220 F. 2d 454, 105 USPQ 233 (CCPA 1955).
Therefore, the claimed invention, as a whole, would have been prima facie obvious to one of ordinary skill in the art before the effective filing date of the instant invention, because the teachings of the prior art reference is fairly suggestive of the claimed invention.
Claim 12 is rejected under 35 U.S.C. 103 as being unpatentable over Zhao et al. (Zhao) (ACS Appl. Mater. Interfaces; published 2021) as applied to Claims 1-3, 5, and 7-11 set forth above, further in view of Yu et al. (Yu) (US 2017/0292008 A1; published Oct. 12, 2017).
The teachings of Zhao as they apply to Claims 1-3, 5, and 7-11 are set forth above and incorporated herein. Additional relevant teachings of Zhao are set forth herein below.
Zhao notes that their work broadens the avenue for the design and preparation of biocompatible polymer-based hydrogels to promote the application of hydrogel sensors with comfortable wearing feel and high sensitivity (abstract).
Hydrogels have emerged as candidates for the fabrication of flexible sensors because of their soft property, flexibility, and satisfactory stretchability. Flexible wearable sensors based on hydrogels would not work when they are damaged by external factors, thus shortening their service life. Therefore, flexible wearable hydrogel sensors should possess a self-healing ability, especially the rapid stimulus-free self-healing property and high healing efficiency (p.11344, col.1, para.2).
Hydrogel constructed by borate ester bonds exhibited the rapid self-healing behavior and high healing efficiency, and the mechanical strength of the corresponding healed hydrogel could be well-recovered. The hydrogels exhibited outstanding dimensional stability, mechanical properties ,and flexibility, and a rapid self-healing ability (p.11344, col.2, para.1).
Additionally, conductivity, mechanical property, and biocompatibility of the hydrogel sensor were also issues of concern. Sodium alginate, a natural and cheap polysaccharide, has drawn great attention because of its good biocompatibility and biodegradability, resulting in wide applications in chemical, biological, pharmaceutical, and food product fields. In addition to good biocompatibility, sodium alginate can also act as a polyelectrolyte to impart the hydrogel with good conductivity.
Zhao does not appear to explicitly disclose wherein the conductive hydrogel exhibits a storage modulus as recited in Claim 12. Yu is relied upon for this disclosure. The teachings of Yu are set forth herein below.
Yu discloses self-healing conductive network compositions, e.g., hydrogels (abstract; para.0002, 0012). Yu discloses that self-healing materials with conductive properties have attracted growing interest in both academia and industry due to their potential applications in a broad range of technologies, such as self-heling electronics, medical devices, artificial skins, and soft robotics. For practical applications, these materials should demonstrate good conductivity and repeatable mechanical and electrical self-healing properties at room temperature as well as decent mechanical strength and flexibility, to mee the requirements for fabrication of flexible devices (para.0003).
Yu discloses that their networks are useful for various applications such as self-healing electronics, artificial skins, soft robotics, and biomimetic protheses (para.0008).
The networks can be characterized of a dynamic storage modulus of at least 10 Kpa, at least 15 Kpa, or at least 20 Kpa, as measured using rheological experiments performed by a rheometer in a frequency sweep mode (para.0040).
One of ordinary skill in the art would have found it prima facie obvious before the effective filing date of the instant invention to combine the teachings of Zhao and Yu and modify the hydrogel to arrive at a dynamic storage modulus as disclosed by Yu. One of ordinary skill in the art would have been motivated to do so in order to obtain the benefit of providing a hydrogel having elastic recovery known to be suitable for various biomedical purposes. One of ordinary skill in the art would have had a reasonable expectation of success in doing so as both Zhao and Yu are directed to self-healing conductive hydrogels, and Yu discloses dynamic storage modulus values that are known and suitable for such materials and biomedical applications.
Therefore, the claimed invention, as a whole, would have been prima facie obvious to one of ordinary skill in the art before the effective filing date of the instant invention, because the combined teachings of the prior art references is fairly suggestive of the claimed invention.
Claim 6 is rejected under 35 U.S.C. 103 as being unpatentable over Zhao et al. (Zhao) (ACS Appl. Mater. Interfaces; published 2021) as applied to Claims 1-3, 5, and 7-11 set forth above, further in view of Kim et al. (Kim) (Nanotechnology; published 2015).
The teachings of Zhao as they apply to Claims 1-3, 5, and 7-11 are set forth above and incorporated herein.
Zhao does not appear to explicitly disclose wherein the filler is as recited in Claim 6. Kim is relied upon for this disclosure. The teachings of Kim are set forth herein below.
Kim discloses graphene oxide/alginate composite hydrogels for enhanced adsorption of hydrophobic compounds. The composite hydrogels embedding reduced graphene oxide (rGO) can be very useful in applications related to drug delivery, waste treatment, and biosensing (title; abstract). Carbon-based nanomaterials (e.g., graphene oxides) have been extensively utilized to fabricate new types of materials for application in various areas, including sensors, electronics, and biomaterials (p.1, col.1).
Reduced graphed oxide is hydrophobic and shows improved interactions with hydrophobic molecules. Materials that have a strong affinity toward hydrophobic aromatic compounds are typically desirable for various application, including removal of hazardous organic compounds and delivery of hydrophobic drugs (p.1, col.2, para.2 to p.2, col.1, para.1).
Kim is directed to fabricating alginate hydrogels embedding rGO flakes for adsorption of hydrophobic molecules with a high capacity (p.2, col.1, para.3).
As discussed above, Zhao discloses the inclusion of tannic acid, which provides the adhesive properties for the hydrogel. One of ordinary skill in the art would have found it prima facie obvious before the effective filing date of the instant invention to combine the teachings of Zhao and Kim and include rGO in addition to, or in lieu of, Zhao’s tannic acid. One of ordinary skill in the art would have been motivated to do so in order to customize the functionalities of the resulting hydrogel based on the desired function of the hydrogel. For example, Kim discloses that the inclusion of rGO into alginate hydrogels imparted the hydrogel with the ability to adsorb hydrophobic molecules with a high capacity, thus allowing for its use to delivery hydrophobic drugs. One of ordinary skill in the art would have had a reasonable expectation of success in doing so as both Zhao and Kim are directed to alginate hydrogels that may be used for biomedical purposes, e.g., biosensing and drug delivery, and Kim discloses that rGO may be incorporated into alginate hydrogels.
With regards to the amount of the rGO, as discussed above, Zhao discloses the amount of tannic acid in the PBST hydrogel is 0.4% (p.11347, col.2, para.1). Thus, the amount of filler is about 5 wt.% relative to the PVA solid content. In the case of using rGO in lieu of, or in addition to, the tannic acid, it would have been obvious to one of ordinary skill in the art before the effective filing date of the instant invention to engage in routine experimentation to determine optimal or workable ranges that produce expected results. In particular, one of ordinary skill in the art would have found it prima facie obvious and would have been motivated to start with the art disclosed amount of tannic acid disclosed by Zhao and engage in routine experimentation to have similar amounts of rGO and/or adjust the amount based on art recognized factors, such as the purpose of the hydrogel (e.g., drug delivery) and the desired and required adsorption need or drug loading need. Where the general conditions of a claim are disclosed in the prior art, it is not inventive to discover the optimum or workable ranges by routine experimentation. In re Aller, 220 F. 2d 454, 105 USPQ 233 (CCPA 1955).
Therefore, the claimed invention, as a whole, would have been prima facie obvious to one of ordinary skill in the art before the effective filing date of the instant invention, because the combined teachings of the prior art references is fairly suggestive of the claimed invention.
Conclusion
Claims 1-3 and 5-12 are rejected. No claims are allowed.
Any inquiry concerning this communication or earlier communications from the examiner should be directed to MONICA A. SHIN whose telephone number is (571)272-7138. The examiner can normally be reached Monday-Friday (9:00AM-5:00PM EST).
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/MONICA A SHIN/Primary Examiner, Art Unit 1616
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