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Joint Event
November 29-30, 2019 | Frankfurt, Germany
28th International Conference on 3rd International Conference on
Diabetes and Endocrinology Diabetes and Metabolism &
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9 CONGRESS
DIABETES
2019
DIABETES
Journal of Endocrine Disorders & Surgery | Volume 3
Electrochemical PANI / cellulose / WO3 sensor to detect acetone derivatives in the
breath of patients with diabetes mellitus
Velia Osuna, Rocío B. Domínguez and Alfredo Márquez-Lucero
CIMAV-CONACYT México
The concentration of acetone derivatives in human breath
was reported within 300–900 ppbv for healthy subjects
and 1800 ppbv for diabetic subjects [4, 5]. This is why acetone
derivatives are proposed as biomarkers present in human
breath for clinical analysis of diseases such as Diabetes
Mellitus (DM). Chemical sensors based on semiconductor
metallic oxides (SMO) have emerged as an active research
area. In those sensors, the surface is modify by adsorption
of gas species and space charge effects, affecting their
conductivity. When SMO sensor is exposed to reducing
conditions, the adsorbed oxygen is removed by reaction with
the reducing gas and the reinjection of electrons reduces SMO
resistance. Since acetone acts as a reducing gas, detection by
sensors such as ZnO [7], In2O3 [8], and SnO2 [9] has been
previously studied but among SMO materials WO3 has been
proposed as the most
suitable material for acetone sensing [10]. WO3 is a ᶯ-type
semiconductor with a band gap between 2.6 and 3.0 eV
[11]. Adsorbed oxygen species on WO3 causes the transfer
of electrons from WO3 conduction band to form O2− and
O− species. The interaction of a reducing gas, such as acetone
with the chemisorbed oxygen, releases an electron to the
conductance band of WO3, which decrease its resistance.
In order to improve the WO3 sensitivity, doping with carbon
sources such as glucose and cotton has been reported
as an effective strategy to reduce the band gap value,
improvingWO3 semiconductive characteristics [12]. In this
work, a nanocomposite of PANI and WO3 doped with carbon
derived from cellulose (C–WO3) was proposed for acetone
detection at room temperature. The sensor was fabricated
with two silver electrodes over an inert substrate with the
PANI/C–WO3 composite deposed in between. Sensibility of
the device was evaluated by EIS at room temperature.
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