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 .
Claims 1-8 are pending as filed on 1/5/2023.
Claim Objections
Applicant is advised that should claim 7 be found allowable, claim 8 will be objected to under 37 CFR 1.75 as being a substantial duplicate thereof. When two claims in an application are duplicates or else are so close in content that they both cover the same thing, despite a slight difference in wording, it is proper after allowing one claim to object to the other as being a substantial duplicate of the allowed claim. See MPEP § 608.01(m).
In the present instance, because claim 4 requires a nanoparticle wherein a carrier encloses the hydrophobic substance, the average particle size of “the carrier” must be the same as the average particle size of the nanoparticle (wherein the carrier encloses the hydrophobic substance). Therefore, claims 7 and 8 are duplicates as they do not differ in scope.
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 1-8 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.
Claim 1 recites “A polysuccinimide derivative…” comprising first and second repeating units. The claim further recites that the polysuccinimide derivative is “under a pH of not greater than 6.” Similarly, claim 4 recites “a nanomaterial” comprising a plurality of nanoparticles “under a pH of not greater than 6.” A pH is a property of an aqueous solution, yet none of the claims recite an aqueous solution. It is therefore not clear whether the claims are limited to aqueous solutions of the recited materials, or, whether the recited pH is a capability (e.g., the recited polysuccinimide or the recited nanomaterial is capable of use in an aqueous solution having a pH of not greater than 6). For examination purposes, the claims have been interpreted according to the second interpretation above (i.e., a polysuccinimide/nanomaterial which is capable of being used in an aqueous solution having a pH not greater than 6).
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.
Claim(s) 1-8 is/are rejected under 35 U.S.C. 103 as being unpatentable over Linh (Biodegradable and pH-responsive Nanoparticles for the Controlled Release of Antibiotics to Infected Wounds; 2021 TwlChE Conference, January 6th 2022, pp 1-18; copy provided by Applicant, cited on IDS filed on 2/2/2023) in view of Sumerlin et al (US 2020/0352161).
As to claims 1-3, Linh discloses a polysuccinimide derivative (PAx) having structural units corresponding to instant formula I (subscripted “n-x”) and formula II (subscripted “x”), as shown in the image below copied from p 5:
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Wherein the second repeating unit (i.e., the AUA-functionalized repeating unit, which corresponds to instant second repeating unit when R1 is C10 straight chain alkyl, meeting instant claims 1 and 2) is present in an amount ranging from 5 to 25 mol% based on 100 mol% of the PSI (corresponding to instant first repeating unit), which falls within the presently claimed range of 1 to 90 mol% (and meets the range recited in claim 3).
As shown in Linh’s reaction on p 11, when the pH is raised above 7, hydrolysis of the succinimide units occurs, while at a pH of 5.0, the polymer is capable of forming a drug loaded nanoparticle (see p 8). Therefore, the polysuccinimide derivative disclosed by Linh is capable of being a component of an aqueous solution under a pH of not greater than 6 (e.g., 5.0), as required by claim 1. Additionally, a plurality of drug-loaded nanoparticles comprising AUA-functionalized PSI as a carrier enclosing a hydrophobic drug (the antibiotic Rifampicin) is capable of being a component of an aqueous solution under a pH of not greater than 6 (e.g., 5.0, see p 8), as required by claims 4-6. The nanoparticles are 100-200 nm (p 14), which falls within the range recited in claims 7-8.
Linh fails to teach the molecular weight of the polymer, and therefore fails to teach “x” and “y” value within a range from 5 to 1000, as presently recited.
Like Linh, Sumerlin discloses functionalizing PSI to form an amphiphilic pH-responsive polymer having hydrophobic (non-functionalized) PSI units and PSI units functionalized with primary amines (figure 1.2), wherein the amphiphilic PSI copolymers assemble into nanoparticles loaded with hydrophobic moieties which disassemble to release loaded components at elevated pH [0009]. Sumerlin teaches that the molecular weight can be about 1000 to 100,000 [0056]. Considering Sumerlin’s disclosure, one having ordinary skill in the art would have reasonably expected the molecular weight range taught by Sumerlin to be an effective range for a functionalized PSI in order to ensure formation of a nanoparticle loaded with a hydrophobic substance comprising the functionalized PSI as a carrier. It would have been obvious to the person having ordinary skill in the art, therefore, to have formed the functionalized PSI disclosed by Linh having any molecular weight within Sumerlin’s disclosed range of 1000 to 100,000, including a molecular weight corresponding to x and y values within the presently claimed range.
Citation of Pertinent Prior Art
In addition to Linh and Sumerlin cited above, the following are considered close prior art references:
Kim et al (Characterizations of Novel Poly(aspartic acid) Derivatives Conjugated with γ-Amino Butyric Acid (GABA) as the Bioactive Molecule, Bulletin of the Korean Chemical Society, vol. 30, no. 12, pp. 3025–3030, Dec. 2009).
Kim discloses poly(aspartic acid) derivatives conjugated with aminobutyric acid (GABA).
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Kim discloses a method of preparation which results in a final product that does not have any succinimide units corresponding to instant formula (I).
Xu et al (Amphiphilic Hexylamine Modified Polysuccinimide:Synthesis, Characterization, and Formation of Nanoparticles in Aqueous Medium, JOURNAL OF MACROMOLECULAR SCIENCE, Part A—Pure and Applied Chemistry, Vol. A40, No. 5, pp. 511–523, 2003).
Xu discloses hexylamine modified PSI:
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and the formation of nanoparticles therefrom (p 516). Xu further teaches applying the material in biodegradable drug delivery systems (p 521). Xu’s PSI unit subscripted “n-m” corresponds to instant unit (I). Xu’s PSI-HA polymer differs from the presently claimed polymer because the hexyl moiety does not have a carboxylic group, and therefore, the unit subscripted “m” does not correspond to instant unit (II).
Conclusion
Any inquiry concerning this communication or earlier communications from the examiner should be directed to RACHEL KAHN whose telephone number is (571)270-7346. The examiner can normally be reached Monday to Friday, 8-5.
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/RACHEL KAHN/ Primary Examiner, Art Unit 1766