DOI: 10.1002/cplu.201200051
Fast and Sensitive Colorimetric Detection of H2O2 and Glucose: A Strategy
Based on Polyoxometalate Clusters
Sen Liu,[a] Jingqi Tian,[a, b] Lei Wang,[a] Yingwei Zhang,[a] Yonglan Luo,[a] Haiyan Li,[a] Abdullah M. Asiri,[c, d]
Abdulrahman O. Al-Youbi,[c, d] and Xuping Sun*[a, c, d]
Natural enzymes have been intensively studied for a long time
and play central roles in biochemistry.[1,2] Natural enzymes as
biological catalysts possess remarkable advantages such as
high substrate specificities and high efficiency under mild con-
ditions and have significant practical applications in medicine,
the chemical industry, food processing, and agriculture. Un-
fortunately, natural enzymes are proteins and inherently bear
some serious disadvantages, such as easy denaturation by en-
vironmental changes, digestion by proteases, as well as time-
consuming and expensive preparation and purification.[3]
Therefore, much effort has been put into developing artificial
enzyme mimics.[2,4–8]
particles[25] have also been applied by our research group in
this assay. All of the above-mentioned nano/microstructure-
based systems, however, suffer from drawbacks, such as rela-
tively long reaction times and relatively high detection limit. It
pushes us to explore new peroxidase mimetics capable of fast
and sensitive detection of H2O2 and glucose.
Polyoxometalates (POMs) are nanometer-sized metal oxide
cluster compounds, which have attracted considerable atten-
tion in the fields of catalysis, medicine, surface science, and
materials science owing to their nanosize and tunable acid/
base, redox, magnetic, catalytic, and photochemical proper-
ties.[26,27] It is well-documented that POMs can catalyze H2O2-
based epoxidation and oxidation of organic substrates by O2
and H2O2 by multistep electron-transfer processes.[28–30] Given
the general concept used in colorimetric detection of H2O2 lies
in the fact that H2O2 oxidizes peroxidase substrate 3,3’,5,5’-tet-
ramethylbenzidine (TMB) in the presence of catalysts to pro-
duce a blue color. It is rational to believe that POMs can be
used as effective inorganic molecular catalysts for the oxida-
tion of TMB using H2O2. Thus, a novel colorimetric detection
system for H2O2 and glucose was subsequently developed. It is
common knowledge that reactions take place at the surface of
catalysts, rather than in the bulk of the catalyst. Small-sized
catalysts have a higher surface-to-volume ratio and hence are
superior to bigger catalysts in terms of catalytic performance.
Given POMs molecular clusters are much smaller in size than
other nano/microstrcutures-based peroxidase mimetics,
a faster reaction kinetics (shorter detection time) and a lower
detection limit may be achieved with such systems based on
POMs. To the best of our knowledge, however, such a concept
has never been proven before.
The accurate determination of H2O2 is of great practical im-
portance in many fields such as food, pharmaceutical, clinical,
industrial and environment protection.[9] It is also important for
minimizing diabetic complications to maintain blood glucose
concentrations within the normal physiological range for con-
trol of diabetes mellitus. Peroxidase has great potential for
practical application and can be used as a diagnostic kit for
H2O2 and glucose.[10] From the point view of artificial enzyme,
it is highly desired to develop peroxidase mimetics for practical
applications. Indeed, several compounds, including hemin,[11]
hematin, hemoglobin, cyclodextrin, and porphyrin, and
a wealth of nanostructures, such as Prussian blue nanoparti-
cles, nanostructured FeS,[12] V2O5 nanowires,[13] bimetallic alloy
nanoparticles,[14] positively-charged gold nanoparticles,[15] Fe3O4
nanoparticles,[16,20] polymer-coated CeO2 nanoparticles,[17]
carbon dots,[18] single-wall carbon nanotubes,[19] and graphene
oxide (GO),[10] have been used as peroxidase-like catalysts for
colorimetric detection of H2O2 and (or) glucose.[21] More recent-
ly, carboxyl-functionalized mesoporous polymers,[22] iron-substi-
tuted SBA-15 microparticles,[23] and photoluminescent carbon
nitride dots,[24] and iron(III)-based coordination polymer nano-
Herein, we demonstrates the proof-of-concept of using sili-
cotungstic acid (H4SiW12O40, denoted as HSiW), a typical POMs
with the size about 1.1 nm[31] as a peroxidase mimetic to cata-
lyze H2O2-based oxidation of various peroxidase substrates in-
cluding TMB, 2,2’-azino-bis(3-ethylbenzothiazoline-6-sulfonic
acid; ABTS), and o-phenylenediamine (OPD) to produce col-
ored solutions. We further demonstrates a simple, fast, sensi-
tive, and selective colorimetric assay to detect H2O2, with the
linear range and detection limit estimated to be from 1 to
20 mm and 0.4 mm, respectively. The application of this colori-
metric assay to glucose detection both in buffer solution and
diluted serum was also demonstrated successfully. This glucose
sensor exhibits excellent performance with a linear range from
1 to 10 mm and detection limit at about 0.5 mm.
[a] Dr. S. Liu, J. Tian, L. Wang, Y. Zhang, Y. Luo, H. Li, Prof. X. Sun
State Key Lab of Electroanalytical Chemistry
Changchun Institute of Applied Chemistry
Chinese Academy of Sciences, Changchun 130022, Jilin (P. R. China)
Fax: (+86)431-85262065
[b] J. Tian
Graduate School of the Chinese Academy of Sciences
Beijing 100039 (P. R. China)
[c] A. M. Asiri, A. O. Al-Youbi, Prof. X. Sun
Chemistry Department, Faculty of Science
King Abdulaziz University, Jeddah 21589 (Saudi Arabia)
[d] A. M. Asiri, A. O. Al-Youbi, Prof. X. Sun
We present proof-of-concept to demonstrate the feasibility
of using HSiW as a model system for colorimetric detection of
H2O2. Figure 1 shows the photographs of solutions of TMB,
TMB+H2O2, TMB+HSiW+H2O2, TMB+HSiW, and HSiW in
Center of Excellence for Advanced Materials Research
King Abdulaziz University, Jeddah 21589 (Saudi Arabia)
Supporting information for this article is available on the WWW under
ChemPlusChem 2012, 00, 1 – 4
ꢀ 2012 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
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