Russian Journal of Applied Chemistry, 2014, Vol. 87, No. 1, pp. 6975.
Pleiades Publishing, Ltd., 2014.
Original English Text S. Taranejoo, M. Moghri, 2014, published in Zhurnal Prikladnoi Khimii, 2014, Vol. 87, No. 1, pp. 7480.
OF ELECTROCHEMICAL INDUSTRY
Development of a Novel Electrochemical Biosensor
Based on Catalytic Properties
of Adenosine Deaminase Immobilized
on Graphene Oxide/Carboxymethyl Chitosan/Multi-W
Carbon Nanotube Platform
and M. Moghri
Chemical Engineering Department, Monash University, Clayton Campus, Melbourne, Australia
Medical Nanotechnology and Tissue Engineering Research Center,
Shahid Beheshti University of Medical Sciences, Tehran, 1985717443 Iran
Islamic Azad University, Kashan Branch, Kashan, Iran
Received January 22, 2014
Abstract—A new type of biosensor was designed based on Adenosine deaminase (ADA) immobilized on gra-
phene oxide (GO)/carboxymethyl chitosan (CMC)/multi-wall carbon nanotube (MWCNT) platform nanostructure,
fabricated and successfully applied (utilized) in Adenosine detection. Square wave voltammetry was used to study
the biosensor catalytic activity. Morphological analysis of the nanostructure was performed by AFM and SEM
methods. The results provided here proved that utilizing GO/CMC/MWCNT leads to effective immobilization
of ADA which was conﬁ rmed by the long term stability of the biosensor during examined intervals. The im-
mobilized ADA activity was examined and the kinetic parameters (K
) were found to be 47.5 M and
5.8 M min
respectively. Furthermore, benznidazole was introduced as a potent ADA inhibitor using virtual
screening. Outstanding inhibition characteristics of benznidazole was observed against ADA. ADA inhibition by
benznidazole was non-competitive with the inhibition constant of 0.42 M. Such an interesting template with
an easy preparation process with low cost can provide a novel matrix for developing biosensors and biocatalysts
based on enzyme immobilization.
Adenosine deaminase (ADA) is a zinc metalloenzyme
involved in purine metabolism and is responsible for the
hydrolysis of Adenosine and Adenosine analogues to
inosine. ADA is essential to the purine metabolic pathway
with an isoelectric point at pH 4.85 . In general, there
are some limitations in application of enzymes such as
structure instability and short operational lifetimes .
High activity of ADA is associated with AIDS, leukemia,
stresses and Parkinson . Alternatively, ADA substrate,
Adenosine, not only exhibits anti-inﬂammatory proper-
ties, but also its extracellular form is helpful against
excessive excitatory amino acid-mediated stimulation.
Furthermore, since some of the drugs used for cancer
chemotherapy are also ADA substrates, inhibition of
this enzyme could be beneﬁ cial to the treatment process.
The evaluation of ADA activity is usually performed
by chromatography and spectroscopic based methods
[4–5]. However, since the absorption bands of substrate
overlap with the absorption bands of products or some
of the inhibitors and slow temporal resolution of HPLC
The text was submitted by author in English.