DETAILED ACTION
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and the fee set forth in 37 CFR 1.17(e) has been timely paid, the finality of the previous Office action has been withdrawn pursuant to 37 CFR 1.114.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 January 20 2026 has been entered.
Receipt of Arguments/Remarks filed on January 20 2026 is acknowledged. Claims 1-29 and 36-41 were/stand cancelled. Claims 30-35 are pending.
The examiner notes that support for the current amendment is found on page
40 of the instant specification.
Notice of Pre-AIA or AIA Status
The present application is being examined under the pre-AIA first to invent provisions.
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.
Claim Rejections - 35 USC § 103
The following is a quotation of pre-AIA 35 U.S.C. 103(a) which forms the basis for all obviousness rejections set forth in this Office action:
A patent may not be obtained though the invention is not identically disclosed or described as set forth in section 102 of this title, if the differences between the subject matter sought to be patented and the prior art are such that the subject matter as a whole would have been obvious at the time the invention was made to a person having ordinary skill in the art to which said subject matter pertains. Patentability shall not be negatived by the manner in which the invention was made.
The factual inquiries set forth in Graham v. John Deere Co., 383 U.S. 1, 148 USPQ 459 (1966), that are applied for establishing a background for determining obviousness under pre-AIA 35 U.S.C. 103(a) 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 under pre-AIA 35 U.S.C. 103(a), the examiner presumes that the subject matter of the various claims was commonly owned at the time any inventions covered therein were made absent any evidence to the contrary. Applicant is advised of the obligation under 37 CFR 1.56 to point out the inventor and invention dates of each claim that was not commonly owned at the time a later invention was made in order for the examiner to consider the applicability of pre-AIA 35 U.S.C. 103(c) and potential pre-AIA 35 U.S.C. 102(e), (f) or (g) prior art under pre-AIA 35 U.S.C. 103(a).
Claims 30-32 and 35 are rejected under pre-AIA 35 U.S.C. 103(a) as being unpatentable over Wang et al. (Langmuir, 2002, cited on PTO Form 1449) in view of Lee et al. (Langmuir, 2005, cited in the Office action mailed on November 17 2020), Canada et al. (USPGPUB No. 20050037058, cited in Office action mailed on May 30 2019), Schlenoff et al. (USPGPUB No. 20040149572, cited in the Office action mailed on November 16 2021) and Sinyagin (USPGPUB No. 20040015115, cited in the Office action mailed on 6/30/23).
Applicant Claims
The instant claims a method for synthesizing a functionalized, multilayer device for treatment of a wound, comprising: a) assembling alternating layers of polyelectrolytes on an elastomeric polymeric support to form a nanoscale polyelectrolyte multilayer in direct contact with said support; b) incubating said multilayer in a bulk solution of a silver salt; c) exposing said multilayer to a reducing agent in an aqueous solution to produce zerovalent silver nanoparticles under conditions such that said multilayer is loaded with from 0.05 to 1 µg/cm2 releasable zerovalent silver nanoparticles; and d) removing said multilayer from said support to provide a functionalized multilayer device, and e) packaging the multilayer device in a sterile package.
Determination of the Scope and Content of the Prior Art
(MPEP §2141.01)
Wang et al. is directed to polyelectrolyte multilayer nanoreactors for preparing silver nanoparticle composites: controlling metal concentration and nanoparticle size. PAH (poly(allylamine hydrochloride)/PAA (poly(acrylic acid)) based multilayers were assembled on polystyrene tissue-culture substrate, glass microscope slides or polished single-crystal silicon wafers. PAH and PAA aqueous solutions were adjusted to the desired pH and then PEM (polyelectrolyte multilayers) were formed by first immersing substrates into the PAH solution followed by PAA solution. The PEM films were immersed in silver acetate (5 mM nominally) for 30 h (i.e. incubated). The Ag(I)-containing PEMs were reduced in a hydrogen atmosphere for 30 h forming Ag(0) nanoparticles (page 3371, experimental section). Figure 2 shows a pH solution of 4.5, 3.5 and 2.5. Dry film thicknesses were about 94, 89, 90, 110 and 140 nm (page 3372, results). Concentrations of silver ranges from 4 to 8% as pH decrease from 4.5 to 2.5 (page 3373, left column, last paragraph). Nanoparticle volume fraction increase from 8 to 24% after five cycles at pH 2.5 (page 3374, right column, last paragraph).
Ascertainment of the Difference Between Scope the Prior Art and the Claims
(MPEP §2141.012)
While Wang et al. teaches reduction of the silver to produce zerovalent silver, Wang et al. does not teach reduction with a reducing agent in an aqueous system. However, this deficiency is cured by Lee et al.
Lee et al. is directed to antibacterial properties of Ag nanoparticle loaded multilayers and formation of magnetically directed antibacterial microparticles. Layer-by-layer assembly of polymers to form multilayer thin films is taught (page 9652, left column, first complete paragraph). It is taught that conversion of Ag ions to zerovalent Ag nanoparticles is needed to achieve sustained release of antibacterial silver from these multilayer thin film (page 9652, right column, first paragraph). Taught is forming film coatings of polyacrylic acid (PAA) and polyacrylamide (PAAm) were formed and crosslinked. The films were suspended in a 5 mM aqueous solution of Ag(Ac). After metal loading the rinsed particles were re-suspended in 1 mM DMAB (aq) to reduce Ag ions (9654).
While Wang et al. suggests concentrations of silver, Wang et al. does not specify a µg/cm2 amount. However, this deficiency is cured by Canada et al.
Canada et al. is directed to a method for producing a silver-containing wound care device. It is taught that the most desirable release rate of silver and zone of inhibition without overdosing the silver into the wound is less than 50 µg/cm2 of silver and most preferably less than about 10 µg/cm2 of silver over a 24 hours period (paragraph 0088). Canada et al. teaches a preferred embodiment wherein a silver-based antimicrobial finish is topically applied to a nonwoven fabric [0001]. The nonwoven fabric may have a fabric weight of between about 20 g/m2 and about 300 g/m2 [0035]. Canada also generically teaches that the metal compound is added in an amount from about 0.01% to about 60% by total weight of the particular treatment composition; preferably, the metal compound is present in an amount from about 0.01% to about 60% of the weight of the fabric (owf), preferably from about 0.05% to about 30% owf, more preferably from about 0.1% to about 10% owf, and most preferably from about 0.3% to about 3.0% owf [0041]. Canada expressly teaches an antimicrobial agent content of 1.7%, 2.2%, 18.1%, 5.1%, 18.4% owf in Examples 1-5 [0093].
While Wang et al. suggests forming the polyelectrolyte layers on a substrate, Wang et al. does not expressly teach an elastomeric support or removing the support. Wang et al. does not teach packaging in a sterile package. However, these deficiencies are cured by Schlenoff et al. and Sinyagin.
Schlenoff et al. is directed to a method of preparing free polyelectrolyte membranes. Taught is a method of preparing thin, continuous isolated polymer membranes and their use in medical wound dressing (paragraph 0002). PEMs must be fabricated on a support. If separation from the support is desired, it is advantageous to separate a membrane form its support in an efficient manner. Taught is a need for creating a polyelectrolyte membrane film which can be quickly and easily separated from the substrate without damaging the membrane or elements within the membranes, without destroying the substrates and without creating a waste stream of organic solvents (paragraph 0006). Taught is the use of a release membrane which frees the membrane from a substrate (paragraph 0042). Polyelectrolytes include polyacrylic acid as well as polyallylamines (paragraph 0048). Additives which can be incorporated into the polyelectrolyte multilayers include silver (paragraph 0059). The releasable membrane structure comprises a substrate that is flexible. Flexible substrates include polymeric and/or elastomeric material (paragraph 0062). It is taught that the polymer membranes are suitable for use as a medical dressing in which the free membrane, upon being released from the substrate, has several advantages such as flexibility, permeability to oxygen, water content, low toxicity and acts as a barrier against the flow of blood, other bodily fluids and pathogens (paragraph 0061).
Sinyagin is directed to a method for treating wound, dressing for use therewith and apparatus and system for fabricating dressing. It is taught that the wound dressing fabrication may be done on a support and packaged for stage before use. The package is sterile and hermetic (paragraph 0072).
Finding of Prima Facie Obviousness Rationale and Motivation
(MPEP §2142-2143)
It would have been obvious to one of ordinary skill in the art at the time of the instant invention to combine the teachings of Wang et al., Canada et al., Lee et al., Schlenoff et al. and Sinyagin and utilize an aqueous solution of DMAB to reduce the silver. One of ordinary skill in the art would have been motivated to utilize this type of reduction as zerovalent Ag nanoparticles are needed in order to achieve sustained release of antibacterial silver ions form polyelectrolyte multilayer films as taught by Lee et al. Since Wang et al. teaches reduction of Ag ions to zerovalent Ag nanoparticles, one skilled in the art would have been motivated to utilize any known method of reduction of Ag including chemical reduction. One skilled in the art would have a reasonable expectation of success as Wang et al. and Lee et al. are both directed to formation of polyelectrolyte multilayers with silver wherein both multilayers include polyacrylic acid.
It would have been obvious to one of ordinary skill in the art at the time of the instant invention to combine the teachings of Wang et al., Canada et al., Lee et al., Schlenoff et al. and Sinyagin and utilize a silver concentration of less than about 50 µg/cm2. One skilled in the art would have been motivated to start with an amount within the range taught by Canada et al. to be useful and not overdose the wound but provides inhibition as taught by Canada et al. and then adjust accordingly. Since the concentration can be manipulated by the pH as taught by Wang et al., one skilled in the art would have been motivated to manipulate the pH and corresponding the amount in order to achieve therapeutic amounts. Canda et al. teaches a weight of the support of between about 20 g/m2 and about 300 g/m2 which corresponds to 2000 µg/cm2 to 30,000 µg/cm2. The metal compound is present in an amount from about 0.01% to about 60% of the weight of the fabric. This corresponds to at the lowest end a metal loading amount of 0.2 µg/cm2 which falls within the scope claimed.
It would have been obvious to one of ordinary skill in the art at the time of the instant invention to combine the teachings of Wang et al., Canada et al., Lee et al., Schlenoff et al. and Sinyagin and utilize an elastomer substrate. One skilled in the art would have been motivated to utilize this substrate as polyelectrolyte layers need to be formed on a substrate. An elastomeric substrate is flexible as taught by Schlenoff et al. This flexibility aids in the release of the substrate from the membrane as taught by Schlenoff et al. One skilled in the art would have been motivated to remove the polyelectrolyte multilayer film from the substrate in order to form a free standing membrane as taught by Schlenoff et al. One skilled in the art would have a reasonable expectation of success as Schlenoff et al. teaches the formation of polyelectrolyte layers made of the same polymers as Wang et al. and suggests that silver can be included. Since Wang et al. suggests various different substrates can be utilized, it would have been obvious to try any known substrate for the formation of polyelectrolyte layers such as those taught in Schlenoff et al. Note: MPEP 2141 KSR International CO. v. Teleflex Inc. 82 USPQ 2d 1385 (Supreme Court 2007).
It would have been obvious to one of ordinary skill in the art at the time of the instant invention to combine the teachings of Wang et al., Canada et al., Lee et al., Schlenoff et al. and Sinyagin and package the free-standing membrane in a sterile package. One skilled in the art would have been motivated to package the free-standing membrane in a sterile package for storage as taught by Sinyagin. Since the membrane could be used as a medical dressing as taught by Schlenoff et al., it would have been obvious to utilize a sterile package to reduce contaminates in the membrane before use.
Claims 33-34 are rejected under pre-AIA 35 U.S.C. 103(a) as being unpatentable over Wang et al. in view of Lee et al., Canada et al., Park et al., Schlenoff et al. and Sinyagin as applied to claims 30-32 and 35 above and in further view of Grunlan et al. (Biomacromolecules, 2005, cited on PTO Form 1449).
Applicant Claims
The instant application claims the bulk solution comprises a silver nitrate and the silver nitrate solution is at least 5 mM.
Determination of the Scope and Content of the Prior Art
(MPEP §2141.01)
The teachings of Wang et al., Lee et al., Canada et al., and Park et al. are set forth above. Wang et al. exemplifies the same polyelectrolyte multilayer with silver acetate. The silver acetate concentration taught is 5 mM.
Ascertainment of the Difference Between Scope the Prior Art and the Claims
(MPEP §2141.012)
While Wang et al. teach incubating the multilayer in a bulk solution of silver salt, Wang et al. does not teach the silver is silver nitrate. However, this deficiency is cured by Grunlan et al.
Grunlan et al. is directed to antimicrobial behavior of polyelectrolyte multilayer films containing cetrimide and silver. Exemplified are polyelectrolyte multilayers made from Polyethyleneimine and polyacrylic acid with sodium nitrate (page 1150, materials section). Taught is the use of both cetrimide and silver to form films. It is taught by combining two antimicrobial agents a hybrid system is created that may provide both large scale bactericidal function on short time scales and extended release over longer time periods (page 1151, right column).
Finding of Prima Facie Obviousness Rationale and Motivation
(MPEP §2142-2143)
It would have been obvious to one of ordinary skill in the art at the time of the instant invention to combine the teachings of Wang et al., Lee et al., Canada et al., Park et al., Schlenoff et al., Sinyagin and Grunlan et al. and either replace the silver acetate of Wang et al. with silver nitrate or utilize silver nitrate in addition to the silver acetate of Wang et al. One of ordinary skill in the art would have been motivated to replace the silver acetate with silver nitrate as both are silver salts which are known to be utilized as the antimicrobial component of a polyelectrolyte multilayer film. Since the silver would react in the same way there is a reasonable expectation of success in utilizing either silver salt. Alternatively, it would have been obvious to one of ordinary skill in the art to utilize silver nitrate in addition to silver acetate to provide for a hybrid system that provides both large scale bactericidal function on a short time scale and extended release over longer time periods as taught by Grunlan et al. Furthermore, as a general principle it is prima facie obvious to combine two compositions each of which is taught by the prior art to be useful for the same purpose, in order to form a third composition to be used for the very same purpose, the idea of combining them flows logically from their having been individually taught in the prior art. See In re Kerkhoven, 626 F.2d 846, 850, 205 USPQ 1069, 1072 (CCPA 1980) MPEP 2144.06.
Regarding the claimed concentration, Wang et al. teaches the same concentration. Furthermore, the amount of a specific ingredient in a composition is clearly a result effective parameter that a person of ordinary skill in the art would routinely optimize. Optimization of parameters is a routine practice that would be obvious for a person of ordinary skill in the art to employ and reasonably would expect success. It would have been customary for an artisan of ordinary skill to determine the optimal amount of each ingredient to add in order to best achieve the desired results. One of ordinary skill in the art would manipulate the amount of silver depending on the desired antimicrobial effect. The amount of an active ingredient is a parameter that a person of ordinary skill in the art would routinely optimize based on the condition being treated, severity of the condition and desired dosing frequency, among other factors.
It would have been obvious to one of ordinary skill in the art at the time of the invention to engage in routine experimentation to determine optimal or workable ranges that produce expected results. 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).
Response to Arguments
Applicant's arguments filed January 20 2026 have been fully considered but they are not persuasive.
Applicants argue that (1) the claims have been amended to recite a range of loaded silver in the device. Canda et al. teaches the desirable release rate is less than 10 µg/cm2. The instant claims refer to a loaded amount which is 10 times less than the lowest range mentioned in Canada et al. for the release rate.
Regarding Applicants’ first argument, firstly, less than 10 µg/cm2 overlaps with the instant claims. Nonetheless, Canda et al. teaches a weight of the support of between about 20 g/m2 and about 300 g/m2 which corresponds to 2000 µg/cm2 to 30,000 µg/cm2. The metal compound is present in an amount from about 0.01% to about 60% of the weight of the fabric. This corresponds to at the lowest end a metal loading amount of 0.2 µg/cm2 which falls within the scope claimed. Thus, the examiner cannot agree that the cited prior art does not render the instantly claimed loading obvious.
Applicants argue that (2) the purpose of Wang is to develop PEMs that retain the silver nanoparticles. This is evidenced by the first sentence in the introduction of Wang which teaches that nanocomposites of inorganic nanoparticles embedded within a polymer matrix. Wang teaches that the reduction of silver cations to zerovalent Ag nanoparticles ca be repeatedly cycled to increase metal concentration in the film. Using this appropriate the volume fraction in the PEM can be increased.
Regarding Applicants’ second argument, a nanoparticle embedded within a polymer matrix is not interpreted as excluding release of the silver. Furthermore, as set forth before, Lee et al. teaches layer-by-layer assembly of polymers to form multilayer thin films is taught (i.e. PEM films). It is taught that conversion of Ag ions to zerovalent Ag nanoparticles is needed to achieve sustained release of antibacterial silver from these multilayer thin film (page 9652, right column, first paragraph). The teachings of Lee et al. would suggest that the zerovalent Ag nanoparticles in Wang are capable of being released. While Wang may teach how to increase the fraction of metal in the film, Wang expressly teaches that the PEM films can be formed with a range of concentrations (abstract, page 3371).
Applicants argue that (3) there is no reasonable expectation of success. None of the reference teach or suggest the amount of zerovalent silver nanoparticles that can or should be loaded. The release rates for silver are for Alphasan which is a zeolite of silver not the instantly claimed silver nanoparticles.
Regarding Applicants’ third argument, the examiner cannot agree that the cited prior art does not tech the same level of loading. As set forth above, Canada et al. clearly teaches a load level which overlaps the instant claims. The test for obviousness is not whether the features of a secondary reference may be bodily incorporated into the structure of the primary reference; nor is it that the claimed invention must be expressly suggested in any one or all of the references. Rather, the test is what the combined teachings of the references would have suggested to those of ordinary skill in the art. See In re Keller, 642 F.2d 413, 208 USPQ 871 (CCPA 1981).
While the product in Canada et al. is different than Wang and the instant claims, this reference still provides the state of the art with regards to concentrations of both loading silver and as well as releasing silver. Nothing has been presented to demonstrate the unexpectedness or criticality of the claimed loading level.
Conclusion
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/ABIGAIL VANHORN/Primary Examiner, Art Unit 1636