Ex Parte Harding et al

Patent Trial and Appeal Board

Dec 7, 2015

12179446 (P.T.A.B. Dec. 7, 2015)

UNITED STA TES p A TENT AND TRADEMARK OFFICE
APPLICATION NO. FILING DATE
12/179,446 07/24/2008
57381 7590
Larson & Anderson, LLC
P.O. BOX 4928
DILLON, CO 80435
12/08/2015
FIRST NAMED INVENTOR
Ian Harding
UNITED STATES DEPARTMENT OF COMMERCE
United States Patent and Trademark Office
Address: COMMISSIONER FOR PATENTS
P.O. Box 1450
Alexandria, Virginia 22313-1450
www .uspto.gov
ATTORNEY DOCKET NO. CONFIRMATION NO.
AGAM.P-059 8146
EXAMINER
DINH,BACHT
ART UNIT PAPER NUMBER
1756
MAILDATE DELIVERY MODE
12/08/2015 PAPER
Please find below and/or attached an Office communication concerning this application or proceeding.
The time period for reply, if any, is set in the attached communication.
PTOL-90A (Rev. 04/07)
UNITED STATES PATENT AND TRADEMARK OFFICE
BEFORE THE PATENT TRIAL AND APPEAL BOARD
Ex parte IAN HARDING, SRIDHAR IYENGAR,
and RICHARD WILLIAMS 1
Appeal2014-001057
Application 12/179 ,446
Technology Center 1700
Before CHUNG K. PAK, ROMULO H. DELMENDO, and
CHRISTOPHER M. KAISER, Administrative Patent Judges.
PAK, Administrative Patent Judge.
DECISION ON APPEAL
This is a decision on an appeal under 35 U.S.C. § 134(a) from the
Examiner's decision2 finally rejecting claims 1-24, which are all of the claims
pending in the above-identified application. A hearing was held on November 4,
2015. 3 We have jurisdiction under 35 U.S.C. § 6(b ).
We AFFIRM.
The subject matter on appeal is directed to "an apparatus and method for
electrochemical detection of an analyte in a sample" which are said to utilize "a
1 The real party in interest is said to be AgaMatrix, Inc. Appeal Brief filed January
18, 2012 ("App. Br.") at 1.
2 Final Action entered May 9, 2012 ("Final Act.") at 1-7 and the Examiner's
Answer entered September 4, 2013 ("Ans.") at 3.
3 A written transcript of the hearing will be entered into the record in due course.
Appeal2014-001057
Application 12/179,446
specific binding relationship between the analyte and at least one reagent provided
in the apparatus as a means for detecting the analyte." Spec. 1, 11. 5-7. According
to pages 4-5 of the Specification:
(a) "analyte" refers to a material of interest that may be present
in a sample. Analytes that are detectable in the present invention are
those that can be associated in a specific-binding interaction with at
least one other reagent to that they can participate in a sandwich,
competition or displacement assay configuration as described herein.
Examples of analytes include antigens or haptens such as peptides (for
example hormones), proteins (for example, enzymes), drugs,
pesticides, microorganisms, antibodies, and nucleic acids that can
participate in sequence specific hybridization reactions with a
complementary sequence[.]
(b) "analyte-specific enzyme component" or reagent refers to a
reagent that includes both an analyte-binding portion and a redox
enzyme portion. An analyte-specific enzyme component is suitably
used as a mobile reagent.
( d) the term "redox enzyme" refers to an enzyme that oxidizes
or reduces a substrate. Such enzyme may generally be known as
oxidases, peroxidases, reductases, or dehydrogenases. Env;mes such
as glucose oxidase, and various peroxidases are commonly used in the
analytical devices ....
( e) the term "redox substrate" refers to a compound or
combination of compounds that interact with the redox enzyme to
produce a chemical potential gradient, in some cases, the
enzyme substrate may directly produce a redox active species
sufficient to create the chemical potential gradient. In others, a
secondary compound may be needed. For example, in the case of
glucose oxidase, the interaction with glucose to produce
gluconolactone and reduced enzyme produces the chemical potential
gradient when the reduced enzyme is oxidized by a mediator
compound, which is the actual redox active species in the chemical,
potential gradient. Thus, in this case the "redox substrate" is the
combination of the substrate compound glucose and the
mediator compound.
2
Appeal2014-001057
Application 12/179,446
Details of the appealed subject matter are recited in illustrative claims 1 and
15, 4 which are reproduced below from the Claims Appendix of the Appeal Brief:
1. A method for determining an analyte in a sample, comprising
the steps of:
(a) introducing the sample to a test cell comprising first and
second electrodes, a mobile test reagent comprising a redox enzyme
portion, and reagents that interact with the mobile test reagent and/or
the analyte, such that the mobile test reagent has a first distribution
relative to the electrodes when analyte is present in the sample and a
second distribution relative to the electrodes when analyte is not
present sample, one of said first and second distributions being
asymmetric with respect to a line between the electrodes,
and the other of the first and second distributions being symmetric or
less asymmetric with respect to the line between the electrodes,
(b) supplying a redox substrate for the redox enzyme in the test
cell, said redox substrate being acted upon by the redox enzyme to
produce a chemical potential gradient between the first and second
electrodes, wherein the magnitude of the chemical potential gradient
is determined by the distribution of the mobile test reagent and thus on
the presence of analyte, and
( c) detecting the chemical potential gradient between the first
and second electrodes to determine analyte in the sample, wherein the
formation and detection of the chemical potential gradient are
performed without application of an external potential or current.
15. An apparatus for determining an analyte in a sample
compnsmg
a test strip comprising first and second electrodes disposed to
contact a test cell for receiving sample, said test strip further a mobile
test reagent comprising a redox enzyme portion, and reagents that
interact with the mobile test reagent and/or the analyte, such that the
mobile test reagent has a first distribution relative to the electrodes
4 Appellants focus on the patentability of independent claims 1 and 15 and then
rely on their arguments drawn to independent claims 1 and 15 to support the
patentability of the remaining claims, namely dependent claims 2-14 and 16-24.
App. Br. 3-7. Therefore, for purposes of this appeal, we limit our discussion to
claims 1and15. 37 C.F.R. § 41.37(c)(l)(iv) (2012).
3
Appeal2014-001057
Application 12/179,446
when analyte is present in the sample and a second distribution
relative to the electrodes when analyte is not present sample, one of
said first and second distributions being asymmetric with respect to a
line between the electrodes, and the other of the first and second
distributions being symmetric or less asymmetric with respect to the
line between the electrodes, and
a circuit for detecting the symmetric or asymmetric distribution
of the mobile test reagent in the test cell in the absence of an applied
external potential or current, and
means for communicating the detected distribution to a user.
App. Br. 9-10 (emphasis added).
The Examiner has maintained the following grounds of rejection:
1. Claims 1--4, 7-10, 13-18, 20-21, and 23-24 under 35 U.S.C. §103(a)
as unpatentable over the combined teachings of Gao 5 and Willner; 6
2. Claims 5-6, 11-12, and 22 under 35U.S.C.§103(a) as unpatentable
over the combined teachings of Gao, Willner, and Cozzette; 7 and
3. Claim 19 under 35 U.S.C. §103(a) as unpatentable over the combined
teachings of Gao, \Villner, and Paek. 8 Final i\ .. ct. 2-7 and Ans. 4-9.
DISCUSSION
Upon consideration of the evidence on this record in light of the arguments
and responses advanced by Appellants and the Examiner, we find no reversible
error in the Examiner's determination that the applied prior art would have
5 US 2006/0160100 Al published in the name of Gao et al. on July 20, 2006
("Gao").
6 US 2004/0245101 Al published in the name of Willner et al. on December 9,
2004 ("Willner").
7 US 2002/0090738 Al published in the name of Cozzette et al. on July 11, 2002
("Cozzette").
8 US 6,478,938 Bl issued in the name of Paek et al. on November 2, 2002
("Paek").
4
Appeal2014-001057
Application 12/179,446
rendered the subject matter recited in claims 1-24 obvious to one of ordinary skill
in the art within the meaning of 35 U.S.C. § 103(a). Accordingly, we sustain the
Examiner's§ 103(a) rejections of the above claims for the reasons set forth in the
Final Action and the Answer. We add the following primarily for emphasis.
The dispositive question raised by Appellants and the Examiner in this case
1s: Has the Examiner erred in determining that the collective teachings of Gao and
Willner would have suggested a step of "detecting the chemical potential gradient
between the first and second electrodes to determine analyte in the sample, wherein
the formation and detection of the chemical potential gradient are performed
without application of an external potential or current" as recited in method claim 1
and "a circuit for detecting the symmetric or asymetric distribution of the mobile
test reagent in the test cell in the absence of an applied external potential or
current" as recited in apparatus claim 15? Compare Final Act. 2-5 and 8-11 and
Ans. 4-7 and 9-16, with App. Br. 3-7. On this record, we answer this question in
the negative.
As recognized by both the Examiner and Appellants, the Specification, at
pages 5-6, paragraph (f), describes the term "chemical potential gradient" recited
in claims 1 and 15 as follows:
[T]he term "chemical potential gradient" refers to a concentration
gradient of a redox active species. It will be appreciated that more
rigorously, the potential gradient arises from a gradient in the ratio of
reduced to oxidized species between the electrodes, however, the idea
of a concentration gradient of one species is more easily visualized
and is therefore used here. When such a gradient is present between
two electrodes, a potential difference is detectable if the circuit is
opened, and a current will flow until the gradient dissipates when the
circuit is closed. It will be appreciated that the chemical potential
gradient is transient in the devices of the invention, and that the
distribution of the redox active species will even out over time when
new redox species stops being created. The term "chemical potential
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Appeal2014-001057
Application 12/179,446
gradient" as used herein refers only to this transient gradient that
arises from the asymmetry of the distribution of redox enzyme and not
to any potential gradient that arises from the application of a potential
difference or current flow between the electrodes.
According to page 5, paragraphs ( e) and ( f), of the Specification, this chemical
potential gradient is said to be produced by interacting a compound or compounds
referred to as "redox substrate" (e.g., glucose) with a redox enzyme (e.g., glucose
oxidase) that oxidizes or reduces the redox substrate. In other words, the express
language of claims 1 and 15, including the recited term "chemical potential
gradient" as defined in the Specification, excludes the application of an external
potential or current in forming and detecting a concentration gradient of a redox
active species and in detecting the symmetric or asymmetric distribution of the
mobile test reagent in the test cell.
Here, the Examiner has found, and Appellants do not dispute, that Gao
teaches a method and an apparatus for determining an analyte in a sample, which
comprises
[introducing] in the presence of the [ redox] substrate, the enzyme 50
[having antibody 48 (a mobile test reagent)], that are concentrated
near the surface of the working electrode 10, [which] undergo redox
reaction ("enzyme 50 will catalyze the reduction of [ redox] substrate
80, thereby oxidized" [0059] ... to yield product 82); thus, creating a
concentration gradient of reduced substrate product 82 or redox
active species between the working electrode 10 and the reference
electrode 6 with the working electrode 10 having higher concentration
of reduced substrate produce 82 or redox active species than the
reference electrode due to the concentration of enzyme at the working
electrode surface. Moreover, Gao discloses the oxidized enzymes
undergo further redox reaction with the redox centre 64 [0059], with
the oxidized enzymes being reduced by the redox centre 64 near the
surface of the working electrode than the reference electrode,
which ... also [constitutes] the concentration gradient of a redox active
species ... .
6
Appeal2014-001057
Application 12/179,446
Compare, e.g., Ans. 10-11 (bracketed portion from Ans. 4-5) with App. Br. 3-7
and Reply Br. 1-6 (emphasis original). The Examiner has also found, and
Appellants do not dispute, that Gao' s disclosure relating to the detection of the
symmetric or asymmetric distribution of the mobile test reagent in the test cell
implies using some sort of a circuit for such detection. Compare Ans. 6 and 14,
with App. Br. 3-7 and Reply Br. 1-6.
As acknowledged by the Examiner, Gao discloses performing the detection
and the formation of a concentration of redox active species with the application of
an external potential or current, rather than without the application of an external
potential or current as required by claim 1 and discloses a circuit for detecting the
symmetric or asymmetric distribution of the mobile test reagent in a test cell in the
presence of an applied external potential or current, rather than in the absence of an
applied external potential or current as required by claim 15. Ans. 6 and 12.
However, the Examiner has correctly found that Willner discloses that the
detection and formation of a concentration of redox active species can be
conducted without the application of an external potential or current in the context
of determining the concentration of an analyte in a test sample. See Ans. 6 and 12-
13, together with Willneri-fi-f 18, 19, 21-25, 33, 34, and 60. In particular, the
Examiner has evinced that:
Gao and Willner disclose the same enzyme 50 (glucose oxidase,
paragraph [0049] of Gao and paragraph [0033] of Willner), the same
substrate (glucose, paragraph [0057] of Gao and paragraph [0033] of
Willner) and the same redox mediator [or centre] ( quinone or
ferrocene, paragraph [0053] of Gao and paragraph [0034] of Willner)
[to produce redox active species9]. Willner [also] discloses against
9 Appellants indicate that the creation of a concentration of redox active species
during a redox reaction without the application of an external potential or current
7
Appeal2014-001057
Application 12/179,446
applying external voltage [(external potential or current)] to two
electrodes in order to deduce the electron transfer reactions or redox
reactions (figure 1, [0018]) because of inaccuracies due to the
presence of interfering agents in the test samples, such as the
biocatalyzed oxidation of glucose is interfere[ d] by ascorbic acid or
uric acid as contaminants of the analyte [0019] ....
See Ans. 12-13, together with Willner,-r,-r 18, 19, 21-25, 33, 34, 57, and 60.
Appellants do not question the Examiner's official notice that blood, serum, saliva,
and urine used as samples in Gao "are known to include glucose['] as well as
ascorbic acid or uric acid[,]" which, according to Willner, are interfering
contaminants for the redox reactions. Compare Ans. 13 with App. Br. 3-7 and
Reply Br. 1-6. In addition, as correctly explained by the Examiner, "[the circuit
for] the detection of the symmetric or asymmetric distribution of the mobile test
reagent in the test cell [recited in claim 15] is simply [a circuit for] the detection of
[the symmetric or asymmetric distribution of the mobile test reagent based on the]
current generated by the transferring of electrons during redox reaction[ s] between
the enzyme, substrate and redox mediator, which is disclosed by both Gao and
Willner[,]" with Willner disclosing the use of such circuit without the application
of an external potential or current. See Ans. 14-15 and Willner i1i1 57 and 60.
Thus, a preponderance of the evidence supports the Examiner's determination that
there is an apparent reason or suggestion for combining the features taught by Gao
and Willner to arrive at the subject matter recited in claims 1 and 15.
Accordingly, we find that Appellants have not identified any reversible error
in the Examiner's §103(a) rejections.
taught by Willner causes or constitutes the "transient chemical potential gradient"
included in claims 1 and 15. Spec. 5-6, i1 (f).
8
Appeal2014-001057
Application 12/179,446
ORDER
In view of the foregoing, the decision of the Examiner to reject claims 1-24
under 35U.S.C.§103(a) is AFFIRMED.
No time period for taking any subsequent action in connection with this
appeal may be extended under 3 7 C.F .R. § 1.13 6( a)( 1 )(iv).
AFFIRMED
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