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 . Claims included in prosecution are claims 1-8.
Response to Restriction Requirement
Applicant's election with traverse of Group I in the reply filed on 4/13/26 is acknowledged. The traversal is on the ground(s) that the prior art cited to show that claim 1 does not constitute a special technical feature that makes contribution over said art is silent with respect to Applicant’s latest amendment, filed 4/13/26.
As a threshold matter, in view of Applicant’s amendment, Group II, encompassing claims 4-5, has been rejoined and is examined on merits.
With respect to Applicant’s traversal, this is not found persuasive because while Li, the initially cited prior art, does not explicitly disclose the retroactively included limitation, it did satisfy the limitations of claim 1 as originally claimed. However, for the purposes of compact prosecution, the Examiner submits that the technical feature of claim 1 is not a special technical feature as it does not make a contribution over the prior art in view of Johnson et al. (US 2020/0123297, Apr. 23, 2020) (hereinafter Johnson) as evidenced by Zhao et al. (Bull. Korean Chem. Soc. 2012, Vol. 33, No. 5) (hereinafter Zhao) as recited in the 103 rejection below.
As such, the requirement is still deemed proper and is therefore made FINAL.
Claims 9-11 are withdrawn from further consideration pursuant to 37 CFR 1.142(b), as being drawn to a nonelected group, there being no allowable generic or linking claim.
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.
1. Claim(s) 1-6 and 8 is/are rejected under 35 U.S.C. 103 as being unpatentable over Johnson et al. (US 2020/0123297, Apr. 23, 2020) (hereinafter Johnson) as evidenced by Zhao et al. (Bull. Korean Chem. Soc. 2012, Vol. 33, No. 5) (hereinafter Zhao).
Johnson discloses bottlebrush polymers copolymers, which can self-assemble into structures of desired morphology (Abstract). Bottlebrush polymers (also referred to a polymer brushes) are macromolecules comprising polymeric sidechains attached to a linear polymeric backbone. Bottlebrush polymers are types of branched or graft polymer, and have unique properties due to their highly branched structure. The high molecular weight and high sidechain grating density typical of bottlebrush polymers can allow these macromolecules to self-assemble into well-defined structures with large domain sizes. Bottlebrush copolymers are bottlebrush polymers comprising two or more different polymeric sidechains (i.e., two or more sidechains of different polymeric composition). These copolymers can be block copolymers (¶ [0003]). Of the various methods for BBCP synthesis, graft through ring-opening metathesis polymerization (ROMP) of norbornene-functionalized macromonomers (MMs) has proven to be particularly effective (¶ [0005]). In particular, in bottlebrush polymers with dissimilar sidechains, the microdomain period scales with the length of the sidechains instead of the overall backbone length. Ultrasmall patterns can therefore be fabricated from a high molecular weight bottlebrush polymer, and the desired pitch of the patterns can be controlled by tuning the sidechain length, thus making possible well-ordered self-assembled thin film nanostructures with diverse applications (¶ [0007]). “Block copolymers" are copolymers comprising homopolymer subunits (i.e., "blocks") covalently linked together. The blocks of a block copolymer are separated into distinct domains. A "diblock bottlebrush copolymer" is a block copolymer comprising two distinct homopolymer domains. A "triblock bottlebrush copolymer" is a block copolymer comprising three distinct homopolymer domains. A diblock bottle brush copolymer can be an "ABC diblock bottlebrush copolymer," defined as a copolymer comprising three blocks (Block A, Block B, and Block C), each of which is a distinct homopolymer domain with a different monomeric subunit (i.e., triblock) (¶ [0110]). In certain embodiments, the bottlebrush polymers comprise 1 to 4000 repeating backbone units, inclusive (¶ [0151]). The described bottlebrush polymer may self-assemble to form any type of nanostructure and have a spherical, lamellar, cylindrical, ellipsoidal, polyhedral, or gyroid shape (satisfies nanoparticle of claim 1) (¶ [0388]). In certain embodiments, A is polyethylene glycol (PEG), polyglycolic acid (PGA), polylactic acid (PLA), or poly(lactic-co-glycolic acid) (PLGA) (¶ [0428]). In certain embodiments, B is polyethylene glycol (PEG), polyglycolic acid (PGA), polylactic acid (PLA), or poly(lactic-co-glycolic acid) (PLGA) (¶ [0430]). Any two polymeric sidechains of Blocks A and B may be of the same or different length, or of the same or different molecular weight (¶ [0470]. The polymeric sidechains of Block A, and Block B of the diblock bottlebrush copolymer may comprise any polymer (¶ [0473]). Suitable polymers include polyethylene glycol (PEG), polyglycolic acid (PGA), polylactic acid (PLA), or poly(lactic-co-glycolic acid) (PLGA) (¶ [0474-0475]). The polymeric sidechains of Blocks A and B may be of any molecular weight. In certain embodiments, the polymeric sidechains of Blocks A and B each independently have a number average molecular weight of about 50 to about 10000 Da (satisfies claim 5) (¶ [0481]). In certain embodiments, no more than two of A, B, C, or D is the same polymer (¶ [0491]). In certain embodiments, each block of the copolymer comprises repeating units of the backbone linked to at least two different polymeric sidechains (¶ [0482]). In certain embodiments, A, B, C, or D is a polyester selected from the group consisting of polyglycolic acid (PGA), polylactic acid (PLA), poly(lactic-co-glycolic acid) (PLGA). In certain embodiments, A, B, C, or D is polylactic acid (PLA). (¶ [0531]). Diblock bottlebrush copolymers described herein may comprise one or more additional blocks to form a triblock bottlebrush copolymer in the case of one additional block (¶ [0594]). In certain embodiments, the method of preparing a bottlebrush polymer comprises one or more ROMP steps. Ring-opening metathesis polymerization (ROMP) is an olefin metathesis strategy for chain growth polymerization that utilizes ring strain of cyclic olefins such as norbornene to drive the polymerization reaction. For olefin metathesis polymerization, the one or more reactive moieties on the macromonomers are olefins. For ROMP reactions, the one or more reactive moieties are cyclic olefins such as norbornene (¶ [0600]). In general, a macromonomer is a polymer comprising a reactive group that allows it to act as a monomer in a polymerization reaction. In certain embodiments, the macromonomer contains two polymeric sidechains. Macromonomers function as monomers in polymerization reactions and, after polymerization, are the repeating units in the larger diblock bottlebrush copolymer (¶ [0615]). In order to effect a polymerization reaction to form a bottlebrush polymer or diblock bottlebrush copolymer described herein, macromonomers are reacted in the presence of a polymerization initiator. In certain embodiments, when polymerization reaction is an olefin metathesis polymerization reaction (e.g. ROMP), the polymerization initiator is a catalyst or promoter of olefin metathesis such as a Grubbs catalyst (¶ [0620]). The bottle self-assembly of the bottlebrush polymers and copolymers can provide useful materials such as drug delivery systems and therapeutic vehicles (satisfies claim 8) (¶ [0623]).
The prior art is not anticipatory insofar as this combination must be selected from different lists/locations in the reference. It would have been obvious, however, to have made an nanoparticle comprising a comprising shape persistent amphiphilic bottlebrush block copolymer (BBCP), as instantly claimed, since all the claimed elements were known in the prior art and one skilled in the art could have combined the elements as claimed by known methods with no change in their respective functions, and the combination yielded nothing more than predictable results to one of ordinary skill in the art. See MPEP § 2143 (I)(A).
Regarding claim 1 reciting interfacial asymmetric bottle brush polyalkylene oxide polymers, as discussed above, Johnson discloses wherein the bottlebrush block copolymer may be a diblock copolymer wherein Block A may be polylactic acid (PLA) and Block B may be polyethylene glycol (PEG) or a triblock copolymer wherein Block A may be polyethylene glycol (PEG), Block B may be polyethylene glycol (PEG), and Block C may be polylactic acid (PLA). Johnson further discloses wherein each block of the copolymer comprises is linked to at least two different polymeric sidechains and that any two polymeric sidechains may be of different length. As such, it would be reasonable for one of ordinary skill in the art to conclude that the interfacial polyalkylene oxide polymers of Johnson would be asymmetric since it may comprise different polymeric sidechains with different lengths.
Regarding claim 1 reciting wherein the shape-persistent amphiphilic BBCP comprises distinct sequential block regions comprising hydrophobic polymers and hydrophilic polymers, as discussed above, Johnson discloses wherein the bottlebrush block copolymer may be a diblock copolymer wherein Block A may be polylactic acid (PLA) and Block B may be polyethylene glycol (PEG) or a triblock copolymer wherein Block A may be polyethylene glycol (PEG), Block B may be polyethylene glycol (PEG), and Block C may be polylactic acid (PLA). As evidenced by Zhao, PEG is hydrophilic and PLA is hydrophobic (Pg. 1641). As such, the BBCP of Johnson comprises said claimed sequential regions comprising hydrophobic polymers and hydrophilic polymers.
Regarding claim 3, "[E]ven though product-by-process claims are limited by and defined by the process, determination of patentability is based on the product itself. The patentability of a product does not depend on its method of production. If the product in the product-by-process claim is the same as or obvious from a product of the prior art, the claim is unpatentable even though the prior product was made by a different process." "The Patent Office bears a lesser burden of proof in making out a case of prima facie obviousness for product-by-process claims because of their peculiar nature" than when a product is claimed in the conventional fashion. Once the examiner provides a rationale tending to show that the claimed product appears to be the same or similar to that of the prior art, although produced by a different process, the burden shifts to applicant to come forward with evidence establishing an nonobvious difference between the claimed product and the prior art product. See MPEP § 2113. Therefore, the method of making the composition/product of the instant claims does not distinguish the compositions from that of the prior art.
However, purely arguendo, if this were not the case, as discussed above, the method of preparing the bottlebrush polymer of Johnson comprises ring-opening metathesis polymerization (ROMP) utilizing cyclic olefins such as norbornene where the macromonomer (i.e., copolymer individual polymers) are reacted with the norbornene. Johnson further discloses that when polymerization reaction is an olefin metathesis polymerization reaction (e.g. ROMP), the polymerization initiator is a catalyst or promoter of olefin metathesis such as a Grubbs catalyst. Additionally, macromonomers function as monomers in polymerization reactions and, after polymerization, are the repeating units in the larger diblock bottlebrush copolymer. As such, suitable macromonomers include PEG and PLA. Therefore, Johnson’s process of synthesizing the BBCOP satisfies the instantly recited limitation.
Regarding claim 4, as discussed above, Johnson discloses wherein the bottlebrush block copolymer may be a triblock BBCP and wherein Block A may be polyethylene glycol (PEG), Block B may be polyethylene glycol (PEG), and Block C may be polylactic acid (PLA). Johnson further discloses that any two polymeric sidechains of Blocks A and B may be of different length, or of different molecular weight. Regarding the recitation “to control brush width and symmetry”, this is merely a recitation of the intended use of the claimed PEG block sidechains. Since the BBCP of Johnson is substantially the same as the claimed composition, comprising substantially the same polymers and PEG block side chains, namely the fact that they may be of different length, or of different molecular weight, one would reasonably conclude that the PEG block side chains of Johnson would be suitable “to control brush width and symmetry”, whether the prior art discloses such use or not.
Regarding the molecular weights recited in instant claim 5, in the case where the claimed ranges "overlap or lie inside ranges disclosed by the prior art" a prima facie case of obviousness exists. See MPEP 2144.05(I). As discussed above, suitable polymers for the polymeric sidechains of Johnson’s BBCP include polyethylene glycol (PEG), polyglycolic acid (PGA), polylactic acid (PLA), or poly(lactic-co-glycolic acid) (PLGA) wherein each sidechain may independently have a number average molecular weight of about 50 to about 10000 Da. Accordingly, because the ranges recited in the instant claims overlap with the range disclosed by Johnson, the range disclosed by Johnson meets the instantly recited limitations.
Regarding claim 6, Johnson discloses wherein the bottlebrush block copolymer may be a diblock copolymer wherein Block A may be polylactic acid (PLA) and Block B may be polyethylene glycol (PEG) or a triblock copolymer wherein Block A may be polyethylene glycol (PEG), Block B may be polyethylene glycol (PEG), and Block C may be polylactic acid (PLA). Johnson further discloses wherein each block of the copolymer comprises is linked to at least two different polymeric sidechains and that any two polymeric sidechains may be of different length, or of different molecular weight. As such, it would be reasonable for one of ordinary skill in the art to conclude that the BBCB of Johnson comprises asymmetric terminal polymers and side chains since it may comprise different polymeric sidechains with different lengths or molecular weights.
2. Claim(s) 7 is/are rejected under 35 U.S.C. 103 as being unpatentable over Johnson et al. (US 2020/0123297, Apr. 23, 2020) (hereinafter Johnson) in view of Zhao et al. (Bull. Korean Chem. Soc. 2012, Vol. 33, No. 5) (hereinafter Zhao).
The teachings of Johnson are discussed above.
Johnson differs from the instant claims insofar as not disclosing the recited hydrophilic to hydrophobic block backbone length ratio.
However, Zhao discloses that It is well known that amphiphilic block copolymers consisting of a hydrophilic PEG block and a hydrophobic PLA block can form micelles. In an aqueous system, the hydrophobic blocks aggregate to form the core and the hydrophilic blocks constitute the outer shell to minimize the free energy. The concentration of surfactants in the bulk at which micelles start forming is defined as CMC, which is considered as an important characteristic of a surfactant (Pg. 1641). For triblock copolymer, the longer PLA lengths are the lower CMC values are. It is because the longer hydrophobic blocks in the micellar core would rearrange to find their lower energy formation. The CMC values of multiblock copolymers are dependent on the relative length of the hydrophilic PEG and hydrophobic PLA; the CMC values decrease with increasing the PLA block length and increase with increasing the PEG blocks (Pg. 1642).
Accordingly, 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. See MPEP 2144.05(II)(A). As discussed above, the hydrophilic PEG and hydrophobic PLA block length affects the CMC value of the resulting micelle, which makes amounts/ratios thereof a result effective variable, since lengths/ratios directly impact the CMC value of the resulting micelle. Accordingly, it would have taken no more than the relative skills of one of ordinary skill in the art through routine experimentation to have arrived at the claimed hydrophilic to hydrophobic block backbone length ratio of 70/10, 60/20, or 40/40 to yield the desired CMC value of the resulting nanoparticle.
Conclusion
Claims 1-8 are rejected.
Claims 9-11 are withdrawn.
No claims are allowed.
Any inquiry concerning this communication or earlier communications from the examiner should be directed to Abdulrahman Abbas whose telephone number is (571)270-0878. The examiner can normally be reached M-F: 8:30 - 5:30.
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/A.A./Examiner, Art Unit 1612
/LEZAH ROBERTS/Primary Examiner, Art Unit 1612
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