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 .
Priority
Applicant’s claim for the benefit of a prior-filed application (PRO 63/181,714, filed 29 April 2021) under 35 U.S.C. 119(e) or under 35 U.S.C. 120, 121, 365(c), or 386(c) is acknowledged.
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and the fee set forth in 37 CFR 1.17(e) has been timely paid, the finality of the previous Office action has been withdrawn pursuant to 37 CFR 1.114.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 14 May 2026 has been entered.
Response to Amendments
Applicant’s amendments filed 14 May 2026 have been entered.
Claims 1-4 and 14 have been amended; Claims 5, 6, 12, and 13 have been canceled (Claims 22-28 were previously canceled); and new Claims 29-32 have been added. Claims 1-4, 7-11, 14-21, and 29-32 are pending.
Regarding the rejections of Claims 2 and 3 under 35 U.S.C. 112(b) or 35 U.S.C. 112 (pre-AIA ), second paragraph, as being indefinite, Applicant’s amendments to Claims 1-3 are sufficient; these rejections have been withdrawn.
Regarding the rejection of Claim 12 under 35 U.S.C. 112(d) or pre-AIA 35 U.S.C. 112, 4th paragraph, as being of improper dependent form, Applicant’s cancellation of Claim 12 renders the rejection moot; this rejection has been withdrawn.
Regarding the rejections of Claims 1-4 and 7-19 under 35 U.S.C. 103 as being unpatentable over CHEN et al. (Electrophoresis 2013, 34, 1877-1885) in view of O’GARA (US 2007/0215547 A1) and LAUBER et al. (US 2019/0126241 A1) and Claim(s) 20 and 21 as being unpatentable over CHEN et al. (Electrophoresis 2013, 34, 1877-1885) in view of O’GARA (US 2007/0215547 A1), LAUBER et al. (US 2019/0126241 A1), and LI et al. (Talanta 2020, 216, 120927), Applicant’s amendments are not sufficient to overcome the obviousness rejections.
Regarding the rejections of Claim(s) 5 and 6 under 35 U.S.C. 103 as being unpatentable over CHEN et al. (Electrophoresis 2013, 34, 1877-1885) in view of O’GARA (US 2007/0215547 A1) and LAUBER et al. (US 2019/0126241 A1) with evidentiary support from YU et al. (Talanta 2016, 161, 860-866), Applicant’s cancelations of Claims 5 and 6 have rendered the rejection moot and therefore, withdrawn.
Response to Arguments
Applicant’s arguments filed 14 May 2026 have been fully considered.
Regarding “Rejections under 35 U.S.C. § 103 are Traversed and/or Rendered Moot” (pg. 7-13), Applicant makes the following arguments:
With respect the rejections of Claims 1-4 and 7-19 under 35 U.S.C. 103 as being unpatentable over CHEN et al. (Electrophoresis 2013, 34, 1877-1885) in view of O’GARA (US 2007/0215547 A1) and further in view of LAUBER et al. (US 2019/0126241 A1) (pg. 7-13),
Applicant states as-amended Claim 1 now reciting “the zwitterionic polymer having a carbon backbone” and “the positively charged moiety and negatively charged moiety are linked to the carbon backbone of the zwitterionic polymer through the urea moiety” is not taught or suggested by CHEN (par. spanning pg. 7-8). Applicant argues the CHEN-disclosed monolithic sulfoalkylbetaine (DMMPPS)-based zwitterionic organic-silica hybrid “does not possess a polymer having a carbon backbone” and further does not comprise “one or more monomer residues that comprise a urea moiety, a positively charged moiety and a negatively charged moiety, wherein the positively charged moiety and negatively charged moiety are linked to the carbon backbone of the zwitterionic polymer through the urea moiety” (pg. 8, par. 1-par. spanning pg.8-9).
Further, Applicant argues O’GARA fails to remedy the deficiencies of CHEN and that the Office’s rejection based on the alleged equivalent substitution of O’GARA’s urea moiety in place of the amide moiety taught by CHEN (i.e., the methacrylamido group) is not an equivalent substation, i.e., “an amide moiety (-C(O)-NH-) and a urea moiety (-NH-C(O)-NH-) are structurally distinct functional groups with consequences for hydrogen bonding capacity, conformational rigidity, and intramolecular interactions”, such that one of ordinary skill “would not arbitrarily exchange one for the other with the requisite reasonable expectation of success” (pg. 9, par. 1).
Further, Applicant argues O’GARA discloses “substituents at the terminus of an alkoxysilane, which is not commensurate with the positively charged moiety and negatively charged moiety linked to the carbon backbone of the zwitterionic polymer through the urea moiety as recited” (par. spanning pg. 9-10). Even further, Applicant argues “there is no teaching in the cited art that would lead one to design a zwitterionic monomer in which the urea group serves as the linking group through which both the positively charged and negatively charged moieties are connected to the polymer's carbon backbone…To select urea from O'Gara's extensive list and apply it not as a terminal substituent (as O'Gara teaches) but as a structural bridge between a carbon backbone and zwitterionic charged moieties (as claim 1 as amended requires) would require application of impermissible hindsight” (par. spanning pg. 9-10).
Finally, Applicant disagrees with the alleged obviousness of utilizing LAUBER teaching the interchangeability of a particle and a monolith because the substitution of one known element for another would have yielded predictable results; Applicant notes that both CHEN and O’GARA explicitly teach away from the use of particles and highlight the benefits of using monoliths over particulates (pg. 10, par. 1).
Regarding the newly added Claims 29-32, Applicant argues the recited prior art fails to teach or make obvious the independent claim (pg. 10-13).
The Examiner respectfully disagrees.
Regarding (i), Applicant argues the CHEN-disclosed monolithic sulfoalkylbetaine (DMMPPS)-based zwitterionic organic-silica hybrid “does not possess a polymer having a carbon backbone” further arguing the “methacrylamido” group is part of the backbone. This is simply not true. When polymerized, DMMPPS or 3-dimethyl-3(N-methacrylamido)propyl) ammonium propane sulfonate (see figure below left), forms a polymer backbone through the methacrylate group as shown below (see FIG. 3A below right of KOTSUCHIBASHI et al., Polymers (Basel), 27 October 2016, 8(11), 380):
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The polymerization occurs via free-radical polymerization via the vinyl double bond of the methacrylamide group in DMMPPS. The side chain, i.e., amido propyl ammonium propane sulfonate, is not part of the backbone of the resultant polymer.
In response to Applicant's arguments against CHEN itself with respect to the lack of teaching of a urea moiety, one cannot show nonobviousness by attacking references individually where the rejections are based on combinations of references. See In re Keller, 642 F.2d 413, 208 USPQ 871 (CCPA 1981); In re Merck & Co., 800 F.2d 1091, 231 USPQ 375 (Fed. Cir. 1986). The rejection is based on the combination of CHEN, O’GARA, and LAUBER.
Regarding (ii), Applicant is arguing that urea and amide moieties are not interchangeable due to their different structures and effects and further argues the prior art fails to disclose or suggest such equivalence. The Examiner respectfully disagrees. Applicant provided sufficient recognition of equivalence between the urea and amide moieties. As stated in the previous Office action, references in the Specification to a urea moiety are all alternatively paired with the other listed moieties, especially amides, both useful as linkages for the zwitterionic polymer, i.e., the equivalency is recognized based on the functionalities of the cited moiety, not their chemical structures. As such, this equivalent substitution is indeed recognized by the Applicant and to argue otherwise that urea and amide moieties are not interchangeable would be arguing against Applicant’s own disclosure. While the MPEP does initially state that “In order to rely on equivalence as a rationale supporting an obviousness rejection, the equivalency must be recognized in the prior art, and cannot be based on applicant’s disclosure or the mere fact that the components at issue are functional or mechanical equivalents. In re Ruff, 256 F.2d 590, 118 USPQ 340 (CCPA 1958)”, the MPEP further indicates that “an applicant’s expressed recognition of an art-recognized or obvious equivalent may be used to refute an argument that such equivalency does not exist.); Smith v. Hayashi, 209 USPQ 754 (Bd. of Pat. Inter. 1980)” (MPEP 2144.06(II)). Even further, it is noted that an express suggestion to substitute one equivalent component or process for another is not necessary to render such substitution obvious. In re Fout, 675 F.2d 297, 213 USPQ 532 (CCPA 1982) (MPEP 2144.06(II)).
Regarding (iii), Applicant argues impermissible hindsight regarding urea as “a structural bridge between a carbon backbone and zwitterionic charged moieties” because O’GARA seemingly teaches urea as a terminal substituent. The Examiner respectfully disagrees. It is agreed that O’GARA teaches the use of urea at the terminus—however, O’GARA leaves open-ended whether the hybrid monoliths are further modified. As noted in p0022, the R6 groups of taught hybrid monoliths can be—among others—amides, urea, and other “functionalities”. One of ordinary skill in the art of chromatography understands that such a list provided by O’GARA is a description of a base chromatographic material from which further specific ligands (e.g., the claimed “positively charged moiety” and “negatively charged moiety”) can be functionalized. However, Applicant’s argument that the Office relied on impermissible hindsight is moot—the combination of CHEN and O’GARA makes obvious this limitation, i.e., CHEN teaches the linkage of a positively charged moiety and a negatively charged moiety through a amide structural bridge and O’GARA teaches the suitable substitution of urea for the amide link. Applicant is seemingly ignoring the substitution of the amide linkage taught by CHEN for the urea linkage taught by O’GARA. One cannot show nonobviousness by attacking references individually where the rejections are based on combinations of references. See In re Keller, 642 F.2d 413, 208 USPQ 871 (CCPA 1981); In re Merck & Co., 800 F.2d 1091, 231 USPQ 375 (Fed. Cir. 1986).
Regarding (iv), Applicant argues the prior art seemingly teaches away from particle-based stationary phases, citing CHEN (pg. 1878, left column, lines 2-4) and O’GARA (p0010-0011 and p0098). However, CHEN is merely describing an alternative to particulate packed columns, not necessarily requiring monolithic columns. For O’GARA, while it may seem that O’GARA is disparaging particulate beds versus monolithic columns, O’GARA recognizes a common issue with both types of stationary phases, i.e., “Nevertheless, prior art hybrid monoliths suffer from many of the same limitations caused by the presence of surface organic groups, as described above for hybrid particles” (p0015). The disclosure of O’GARA is indeed focused on addressing this issue present on the surface of the stationary phase and provides a solution that can be applied to both particulate and monolithic columns. While indeed particulate packed beds may experience such issues as higher pressure drop compared with monolithic columns, the claimed invention and the cited prior art disclosures are not concerned about the uses of such columns, rather the make-up and compositions of these columns are being considered for patentability.
Regarding (v), after careful search and consideration, new grounds of rejection have been provided for new Claims 29-32.
Finally, Applicant argues the rejections of Claims 20 and 21 should be withdrawn for the same reasons that Claim 1 is patentable over the prior art (pg. 13, par. 3). The Examiner respectfully disagrees; the obviousness rejection of Claim 1 has been maintained.
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.
Claim(s) 1-4, 7-11, and 13-19 is/are rejected under 35 U.S.C. 103 as being unpatentable over CHEN et al. (Electrophoresis 2013, 34, 1877-1885) in view of O’GARA (US 2007/0215547 A1) and further in view of LAUBER et al. (US 2019/0126241 A1).
Regarding Claim 1, CHEN discloses a sulfoalkylbetaine-based zwitterionic organic-silica hybrid monolith (§1, pg. 1878, par. 3). Said monolith is prepared as a column with vinyltrimethoxysilane (VTMS), and tetramethoxysilane (TMOS) first forming the bulk of the silica monolith and the addition of 3-dimethyl-3(N-methacrylamido)propyl) ammonium propane sulfonate (DMMPPS) as the zwitterionic polymer (§2.2, pg. 1879) (i.e., [a] chromatographic material comprising (a) a bulk material and (b) a zwitterionic polymer covalently linked to a surface of the bulk material, the zwitterionic polymer comprising one or more residues that comprise…, a positively charged moiety and a negatively charged moiety; see FIG. 1 for structure of DMMPPS—the positively charged moiety is shown as the quaternary ammonium group separated from the amide linkage by C3 and the negatively charged moiety is shown as the sulfonate group separated from the quaternary group by another C3; §3.6, par. 1).
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CHEN fails to explicitly disclose (1) the one or more monomer residues comprise a urea moiety, (2) the positively charged moiety and negatively charged moiety are linked to the carbon backbone of the zwitterionic polymer through the urea moiety, or (3) the zwitterionic polymer has a specific surface coverage on the bulk material of from 0.5 µmol/m2 to 40 µmol/m2.
O’GARA discloses the preparation of hybrid polymeric monoliths for use in liquid chromatography (p0002, p0017). O’GARA further discloses that the polymer binding ligands, which include one or more moieties including amide and urea (p0022, p0097, Claim 7), on the monoliths have certain surface concentrations, e.g., “between about 1.0 and about 3.4 µmol/m2” (p0023), which reads upon the claimed range of from 0.5 µmol/m2 to 40 µmol/m2. Advantageously, such polymeric surface concentrations reduce or eliminate reduced retention times and peak compression and thereby negate the need for high backpressures during chromatography (p0016). (Such issues are similarly recognized by CHEN; see §1, par. spanning pg. 1877-1878; §3.1, pg. 1880). Thus, one of ordinary skill in the art prior to the effective filing date of the claimed invention would have found it obvious to provide a specific surface coverage of at least 0.5 µmol/m2 as taught by O’GARA for the zwitterionic polymers on bulk material taught by CHEN.
Further, as noted, O’GARA teaches that the one or more moieties includes amide and urea (i.e., one or more monomer residues that comprise a urea moiety; p0022, p0097, Claim 7). Thus, prior to the effective filing date of the claimed invention, one of ordinary skill in the art would have found it obvious to substitute a urea moiety as taught by O’GARA as a functional group in place of an amide moiety as taught by CHEN because such an equivalent substitution is disclosed in the prior art and is acknowledged by the Applicant in their disclosure to have no differential effect, i.e., the substitution of one known element for another would have yielded predictable results (MPEP §2143(I)B). An express suggestion to substitute one equivalent component or process for another is not necessary to render such substitution obvious. In re Fout, 675 F.2d 297, 213 USPQ 532 (CCPA 1982) (MPEP 2144.06(II)). Furthermore, because O’GARA teaches such a substitution to be obvious, the limitation “the positively charged moiety and negatively charged moiety are linked to the carbon backbone of the zwitterionic polymer through the urea moiety” is necessarily met when considering the CHEN-disclosed zwitterionic polymer having the positively and negatively charged moieties separated by the amide linkage group.
Modified CHEN is deficient in disclosing the chromatographic material/bulk material comprises a particle.
LAUBER discloses high purity chromatographic material (HPCM) comprising a chromatographic core material that is a hybrid inorganic-organic material (p0007). The HPCM is in the form of a particle, monolith, or a superficially porous particle or monolith (i.e., wherein the chromatographic material/bulk material comprises a particle; p0059). Thus, the suitability of preparing a chromatographic material as a particulate or as a monolith is known in the art. The claim would have been obvious to one of ordinary skill in the art prior to the effective filing date of the claimed invention because the substitution of one known element for another, e.g., the particulate material disclosed by LAUBER as the bulk for the chromatographic material made obvious by modified CHEN, would have yielded predictable results (MPEP §2143(I)B).
Regarding Claims 2-4, modified CHEN makes obvious the chromatographic material of Claim 1. As noted earlier, CHEN teaches the linkage of a positively charged moiety and a negatively charged moiety through an amide structural bridge (see FIG. 1 for the structure of DMMPPS—the positively charged moiety is the quaternary ammonium group separated from the amide linkage by C3 and the negatively charged moiety is the sulfonate group separated from the quaternary group by another C3; §3.6, par. 1; i.e., the positively charged moiety is a quaternary ammonium moiety (Claim 3); the negatively charged moiety is a… sulfonate moiety (Claim 3); the zwitterionic polymer comprises a residue of amonomer that comprises a sulfobetaine moiety (Claim 4)) and O’GARA teaches the suitable substitution of urea for the amide link (i.e., wherein the urea moiety is a C1-C12 alkyl urea group (Claim 2)).
Regarding Claim 7, modified CHEN makes obvious the chromatographic material of Claim 1. As noted, CHEN discloses a TMOS/VTMS organic-silica monolith which provides organosilane residues for linking to the zwitterionic polymer (i.e., wherein the zwitterionic polymer is covalently linked to the surface of the bulk material through a residue of an organosilane monomer; §2.2, pg. 1879; FIG. 1).
The limitation “that is able to participate in radical polymerization” is directed toward an optional property of the claimed organosilane monomer. Claim scope is not limited by claim language that suggests or makes optional but does not limit a claim to a particular structure. Because the prior art, singly or in combination, teaches all claimed structural language, the “adapted to” or “adapted for” clause in question is optional and does not limit the claim. The clause expresses the intended use of the claimed structural element and thereby, does not further limit the claim (MPEP §2111.04). However, even if positively recited, the organosilane monomer disclosed by CHEN is indeed capable and does provide for radical polymerization.
Regarding Claims 8 and 9, modified CHEN makes obvious the chromatographic material of Claim 1. CHEN further discloses vinlytrimethoxysilane (i.e., wherein the zwitterionic polymer is covalently linked to the surface of the bulk material through a residue of an alkenyl-functionalized organosilane monomer; wherein the alkenyl-functionalized organosilane monomer is selected from… vinyltrimethoxy silane; §2.2, pg. 1879).
Regarding Claim 10, modified CHEN makes obvious the chromatographic material of Claim 1. LAUBER further discloses the high purity chromatographic material (HPCM) comprising the chromatographic core material is in the form of a superficially porous particle (i.e., wherein the bulk material is a porous or a superficially porous material; p0059).
Regarding Claim 11, modified CHEN makes obvious the chromatographic material of Claim 10. LAUBER further discloses the average pore diameter of the HPCM ranges from 110 to 500 Å (p0066), which reads upon the claimed surface pore size ranging from 45 to 3000 Å.
Regarding Claim 13, modified CHEN makes obvious the chromatographic material of Claim 1. As noted earlier, LAUBER further discloses the HPCM is in the form of a particle, monolith, or a superficially porous particle or monolith (i.e., wherein the bulk material is a particulate material; p0059).
Regarding Claim 14, modified CHEN makes obvious the chromatographic material of Claim 13. LAUBER further discloses the particulate material has an average particle size of about 0.3-100 µm (p0067), which reads upon the claimed range of a particle size ranging from 0.3 to 100 µm.
Regarding Claim 15, modified CHEN makes obvious the chromatographic material of Claim 1. The instant limitation requiring that “the chromatographic material is stable over pH ranging from 2 to 11” is directed toward properties inherent to the claimed chromatographic material. The claiming of a new use, new function or unknown property which is inherently present in the prior art does not necessarily make the claim patentable (In re Best, 562 F.2d 1252, 1254, 195 USPQ 430, 433 (CCPA 1977)). Modified CHEN makes obvious all limitations of the claimed chromatographic material of Claim 1; any claimed properties derived from such limitations are necessarily present.
Regarding Claims 16-18, modified CHEN makes obvious the chromatographic material of Claim 1. As noted above, CHEN discloses an organic-silica hybrid (i.e., wherein the bulk material comprises an inorganic material, a hybrid inorganic-organic material, an organic polymeric material, or a combination thereof; §2.2, pg. 1879) comprising TMOS and VTMS (i.e., wherein the bulk material comprises an inorganic-hybrid material that comprises a network of (a) silicon atoms having four silicon-oxygen bonds and (b) silicon atoms having one or more silicon-oxygen bonds and one or more silicon-carbon bonds; wherein the bulk material comprises a substituted or unsubstituted alkylene, alkenylene, alkynylene, or arylene moiety bridging two or more silicon atoms; FIG. 1).
Regarding Claim 19, modified CHEN makes obvious the chromatographic material of Claim 1. As noted above, CHEN discloses an organic-silica hybrid comprising TMOS and VTMS formed by condensation reaction (i.e., wherein the bulk material is formed by hydrolytically condensing (a) one or more silane compounds of the formula SiZ1Z2Z3Z4…; §2.2, pg. 1879; FIG. 1).
Claim(s) 20 and 21 is/are rejected under 35 U.S.C. 103 as being unpatentable over CHEN et al. (Electrophoresis 2013, 34, 1877-1885) in view of O’GARA (US 2007/0215547 A1) and further in view of LAUBER et al. (US 2019/0126241 A1), as applied to Claim 1 above, and further in view of LI et al. (Talanta 2020, 216, 120927).
Regarding Claims 20 and 21, modified CHEN makes obvious the chromatographic material of Claim 1. Modified CHEN is deficient in disclosing the zwitterionic polymer further comprises weak cation exchange groups or weak anion exchange groups or that the weak cation exchange groups comprise carboxyl groups and the weak anion exchange groups comprise primary, secondary or tertiary amine groups.
LI discloses zwitterionic stationary phases for HILIC and specifically a weak cation and weak anion zwitterionic polymer (i.e., the zwitterionic polymer further comprises weak cation exchange groups or weak anion exchange groups; §1, pg. 2, par. 3). The stationary phase G-Diol-Cys presents a carboxylate group and a primary amine group (i.e., the weak cation exchange groups comprise carboxyl groups and the weak anion exchange groups comprise primary, secondary or tertiary amine groups; abstract; see FIG. 1). This zwitterionic phase with weak cation and anion groups advantageously offers higher flexibility for controlling surface charge especially compared with zwitterionic polymers offering strong cation and anion groups, e.g., sulfonic and quaternary ammonium groups (§1, pg. 2, par. 3). Thus, prior to the effective filing date of the claimed invention, one of ordinary skill in the art would have found it obvious to provide weak cation exchange groups and weak anion exchange groups, including carboxyl groups and primary, secondary, or tertiary amine groups as disclosed by LI for the chromatographic material of modified CHEN.
Claim(s) 29-32 is/are rejected under 35 U.S.C. 103 as being unpatentable over CHEN et al. (Electrophoresis 2013, 34, 1877-1885) in view of BIEHL et al. (Polymers, 2018, 10, 91).
Regarding Claim 29, CHEN discloses a sulfoalkylbetaine-based zwitterionic organic-silica hybrid monolith (§1, pg. 1878, par. 3). Said monolith is prepared as a column with vinyltrimethoxysilane (VTMS), and tetramethoxysilane (TMOS) first forming the bulk of the silica monolith (i.e., [a] chromatographic material comprising (a) a bulk) and the addition of 3-dimethyl-3(N-methacrylamido)propyl) ammonium propane sulfonate (DMMPPS) as the zwitterionic polymer (i.e., a zwitterionic polymer covalently linked to a surface of the bulk material… the zwitterionic polymer having a carbon backbone and comprising one or more monomer residues that comprise an amide moiety, a positively charged moiety, and a negatively charged moiety; §2.2, pg. 1879) (see FIG. 1 for structure of DMMPPS—the positively charged moiety is shown as the quaternary ammonium group separated from the amide linkage by C3 and the negatively charged moiety is shown as the sulfonate group separated from the quaternary group by another C3; §3.6, par. 1).
CHEN fails to explicitly disclose the zwitterionic polymer is covalently linked to a surface of the bulk material via a methacryloxy moiety or an acryloxy moiety present at the surface of the bulk material.
BIEHL discloses the covalent attachment of zwitterionic polymers to a polymeric shell comprising SiO2 (abstract). Briefly, the covalent grafting requires the initial functionalization of the SiO2 surface with initiators for polymerization, e.g., through the use of methacryloxy propyl trimethoxysilane (MPS) (§4, par. 2-3). The nature of the problem to be solved, i.e., the attachment of a zwitterionic polymer to a silica surface as taught by CHEN, would have led one of ordinary skill in the art to combine the elements as claimed by known methods, i.e., the initial functionalization of the silica surface with a methacryloxy group as taught by BIEHL, with no change in their respective, individual functions, and the combination would have yielded nothing more than predictable results (MPEP §2143(I)A).
Regarding Claims 30-32, modified CHEN makes obvious the chromatographic material of Claim 29. As noted earlier, CHEN teaches the linkage of a positively charged moiety and a negatively charged moiety through an amide structural bridge (see FIG. 1 for the structure of DMMPPS—the positively charged moiety is the quaternary ammonium group separated from the amide linkage by C3 and the negatively charged moiety is the sulfonate group separated from the quaternary group by another C3; §3.6, par. 1; i.e., the positively charged moiety and the negatively chargd moiety are linked to the carbon backbone of the zwitterionic polymer through the amide moiety (Claim 30); the positively charged moiety is a quaternary ammonium moiety (Claim 31); the negatively charged moiety is a… sulfonate moiety (Claim 31); the zwitterionic polymer comprises a residue of a monomer that comprises a sulfobetaine moiety (Claim 32)).
Conclusion
The prior art made of record and not relied upon is considered pertinent to applicant's disclosure:
LAUBER et al. (US 2020/0332028 A1), a high purity chromatographic material includes labeling moieties covalently bonded to the stationary phase through a secondary amine, urea, or amide linkage (p0200).
Any inquiry concerning this communication or earlier communications from the examiner should be directed to RYAN B HUANG whose telephone number is (571)270-0327. The examiner can normally be reached 9 am-5 pm EST.
Examiner interviews are available via telephone, in-person, and video conferencing using a USPTO supplied web-based collaboration tool. To schedule an interview, applicant is encouraged to use the USPTO Automated Interview Request (AIR) at http://www.uspto.gov/interviewpractice.
If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, In Suk Bullock can be reached at (571)272-5954. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
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/Ryan B Huang/Primary Examiner, Art Unit 1772
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