DETAILED ACTION
Response to Amendment
This is a final office action in response to a communication filed on March 11, 2026. Claims 1-3 and 6-14 are pending in the application.
Status of Objections and Rejections
All objections from the previous office action are maintained.
Claim Rejections - 35 USC § 103
The text of those sections of Title 35, U.S. Code not included in this action can be found in a prior Office action.
Claim(s) 1-3, 6, and 14 is/are rejected under 35 U.S.C. 103 as being unpatentable over Aburaya (US 2021/0208138) in view of Duan (US 11,185,836).
Regarding claim 1, Aburaya teaches a metal nanoparticle-magnetic particle complex ([Abstract]: a composite particle), comprising:
a core comprising a magnetic particle (¶41: the magnetic particles as a core);
a first shell comprising metal nanoparticles (¶46: gold particles) and formed on a surface of the core (¶78: mixing the modified magnetic particles and the modified gold particles via avidin-biotin interaction; Examiner notes here that it would result in the gold nanoparticles formed on the surface of the magnetic core particles); and
a second shell comprising response factors (¶116: the composite particle is modified with the first binding substance that can bind to the test substance) and formed on a surface of the first shell (Examiner notes here that the first binding substance that modifies the composite particle constitute the second shell formed on the first shell),
wherein the core further comprises the first linker compounds (¶86: the first organic substance of the modified magnetic particle),
wherein the metal nanoparticles of the first shell are metal nanoparticles (Au) conjugated with second linker compounds (¶86: the second organic substance of the modified gold particle),
wherein at least some of the second linker compounds of the first shell bind to the first linker compounds of the core (¶86: binding of the first organic substance of the modified magnetic particle and the second organic substance of the modified gold particle),
wherein the second shell further comprises the first linker compounds (¶98: the composite particle is modified with a first binding substance that bind to the test substance; ¶67: a binding substance of the first organic substance and the second organic substance corresponds to the above-mentioned organic substance),
wherein some of the first linker compounds of the second shell bind to some of the second linker compounds of the first shell,
wherein the response factors of the second shell are response factors conjugated with the second linker compounds (Examiner notes that the first linker compounds is functionalized the outer surface of the core, and the first shell is functionalized with the second linker compounds, both inner surface and the outer surface, and the second linker compounds at the inner surface of the first shell would conjugate with the first linker compounds of the core; thus, the first linker compounds of the second shell would necessarily bind to some of the second linker compounds of the first shell so that the second shell, i.e., the response factors, would conjugate with the second linker compounds), and
wherein at least some of the second linker compounds of the second shell bind to some of the first linker compounds of the second shell that do not bind to the second linker compounds of the first shell (since the second shell, i.e., the response factors, conjugated with the second linker compounds, which would be able to bind to some of the first linker compounds of the second shell, but not the second linker compounds of the first shell).
Aburaya does not explicitly disclose wherein a diameter of the magnetic particle is 2 µm to 50 µm, wherein the number of metal nanoparticles immobilized on the surface of one magnetic particle is about 1000-5000.
However, Duan teaches magnetic nanoparticles that can be introduced by polydopamine enabled conjugation chemistry for molecular separation and biosensing (pp. 12-13; Fig. 13). A magnetic chain structure made of a plurality of magnetic particles ([Abstract]), loaded with gold nanoparticles (AuNPs) (Fig. 9; col. 2, ll. 42-44). The magnetic chain structures may have applications in ultrasmall sensing devices, for loading metal nanocatalyst and applications in medical diagnostics (col. 11, ll. 34-53). The magnetic particle has a diameter in the range of about 20 nm to about 2 µm (col. 4, ll. 27-28), which overlaps the recited range. The gold nanoparticles may be of any suitable size and shape (col. 11, ll. 15-16). For purpose of illustration only, the gold nanoparticles may have a mean diameter in the range of about 10 nm to about 20 nm (col. 11, ll. 16-18). Thus, the size of the gold nanoparticle would be a result-effective variable for routine optimization to obtain desired performance. When the diameter of the magnetic particle is 1 µm and the diameter of the gold nanoparticle is 20 nm, the maximum loading numbers of the gold nanoparticles on each magnetic particle is around 10,000, which overlaps the recited range.
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have modified Aburaya by adjusting the diameter of the magnetic particle and adjusting the number of the loaded metal nanoparticles within the claimed ranges as suggested by Duan because they are suitable geometries for magnetic particles loaded with gold nanoparticles in the field of diagnostic sensing devices. In the case where the claimed ranges "overlap or lie inside ranges disclosed by the prior art" a prima facie case of obviousness exists. In re Wertheim, 541 F.2d 257, 191 USPQ 90 (CCPA 1976); In re Woodruff, 919 F.2d 1575, 16 USPQ2d 1934 (Fed. Cir. 1990). MPEP 2144.05(I). Similarly, a prima facie case of obviousness exists where the claimed ranges or amounts do not overlap with the prior art but are merely close. Titanium Metals Corp. of America v. Banner, 778 F.2d 775, 783, 227 USPQ 773, 779 (Fed. Cir. 1985). MPEP 2144.05(I). Further, since the gold nanoparticle as disclosed by Duan may be any suitable size, it renders the size of gold nanoparticle a result-effective variable and can be optimized through routine experimentation. MPEP 2144.05 (II)(B). Based on the different size of the gold nanoparticles, the loading number on each magnetic particles would also be varied and optimized through routine experimentation.
The preamble “for electrochemical biosensors” is deemed to be a statement with regard to the intended use and are not further limiting in so far as the structure of the product is concerned. In article claims, a claimed intended use must result in a structural difference between the claimed invention and the prior art in order to patentably distinguish the claimed invention from the prior art. MPEP § 2111.02(II). The apparatus as taught by modified Aburaya in view of Duan is identical to the presently claimed metal nanoparticle-magnetic particle complex and would therefore would have the ability to perform the use recited in the claim.
Regarding claim 2, Aburaya teaches wherein a diameter of the metal nanoparticles is 1 to 100 nm (¶50: 50 nm).
Regarding claim 3, Aburaya teaches wherein a metal of the metal nanoparticles comprises gold (¶46: gold particles).
Regarding claim 6, Aburaya teaches wherein the first linker compound comprises avidin (¶173: magnetic particles modified with avidin).
Regarding claim 14, Aburaya and Duan disclose all limitations of claim 1, including wherein a diameter of the magnetic particle is 2 µm to 5 µm (Duan, col. 9, ll. 20-21: using larger magnetic particles having a size of about 2 µm).
Response to Arguments
Applicant’s argument(s) has/have been considered but are unpersuasive.
Applicant argues Aburaya’s composite particle has difference in use and operating mechanism (Response, p. 5, para. 3), and the gold nanoparticle of Aburaya has a different function for “labeling” or “coloring” (p. 6, para. 2). This argument is unpersuasive because a recitation of the intended use of the claimed invention must result in a structural difference between the claimed invention and the prior art in order to patentably distinguish the claimed invention from the prior art. If the prior art structure is capable of performing the intended use, then it meets the claim.
Appellant’s arguments against Aburaya regarding the different numbers of metal nanoparticles bound to a single magnetic particle (p. 5, last para.) principally attack the references individually and, therefore, do not address adequately the rejection the Examiner presents in the record. See In re Keller, 642 F.2d 413, 426 (CCPA 1981) (“[O]ne cannot show non-obviousness by attacking references individually where, as here, the rejections are based on combinations of references.”), 425 (“[T]he test [for obviousness] is what the combined teachings of the references would have suggested to those of ordinary skill in the art.”); see also In re Merck & Co., 800 F.2d 1091, 1097 (Fed. Cir. 1986); and KSR Int’l Co. v. Teleflex Inc., 550 U.S. 398, 418 (2007) (“[T]he [obviousness] analysis need not seek out precise teachings directed to the specific subject matter of the challenged claim, for a court can take account of the inferences and creative steps that a person of ordinary skill in the art would employ.”).
Applicant argues that the combination of Aburaya and Duan is not obvious by a conclusive statement that “when a structure having a large amount of nanoparticles adhered to the surface of magnetic particles as disclosed in Duan is applied to Aburaya, the essential technical task of Aburaya, i.e., the rapid dispersibility (mobility), will be completely lost (p. 7, last para.). This argument is unpersuasive because Applicant does not provide any evidence to support its conclusion. There is no evidence that Duan “teaches away” this feature because both Aburaya and Duan are analogous art. Aburaya teaches a composite for an immunochromatography (Aburaya, ¶2), which can be used for detect influenza virus based on the binding between the labeled antibody and the antigen, i.e., for biosensing. Duan teaches core-shell magnetic particles, when loaded with metal nanocatalysts and surrounded by a cross-linked polymeric shell of a dopamine-based material (Duan, col. 3, ll. 36-50), tailored to potential applications such as biosensing (p. 13, Fig. 13). Thus, it would have been obvious to one of ordinary skill in the art to arrive the claimed subject matter of claim 1 by modifying Aburaya by adjusting the magnetic particle diameter and the loaded number of metal nanoparticles as taught by Duan.
Conclusion
THIS ACTION IS MADE FINAL. Applicant is reminded of the extension of time policy as set forth in 37 CFR 1.136(a).
A shortened statutory period for reply to this final action is set to expire THREE MONTHS from the mailing date of this action. In the event a first reply is filed within TWO MONTHS of the mailing date of this final action and the advisory action is not mailed until after the end of the THREE-MONTH shortened statutory period, then the shortened statutory period will expire on the date the advisory action is mailed, and any extension fee pursuant to 37 CFR 1.136(a) will be calculated from the mailing date of the advisory action. In no event, however, will the statutory period for reply expire later than SIX MONTHS from the mailing date of this final action.
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/C. SUN/Primary Examiner, Art Unit 1795