Nitric oxide (NO) plays major roles in various physiological
processes,
such as neurotransmission, vasodilation, blood pressure monitoring,
and immune response. Precise regulation of NO concentration in our
body can be measured as a potential biomarker for numerous diseases
such as hypertension, diabetes, Parkinson’s disease, ischemia,
and rheumatoid arthritis. In this report, an electrochemical NO sensor
was fabricated using a nanocomposite material consisting of Pt and
TiO2 nanoparticles (Pt-TiO2 NPs). Pt and TiO2 nanoparticles were synthesized using the sol–gel method.
NO sensing measurements were carried out using a Pt-TiO2 NPs-modified glassy carbon (GC) electrode after adding various concentrations
of NO. The nanoparticles-modified GC electrode demonstrated high sensitivity
(∼7.81 μA mM–1cm–2) in a wide linear detection range (∼10 nM to 17.79 mM). The
sensor exhibited a very low detection limit (∼2.47 nM), high
stability, and excellent selectivity toward NO. NO detection using
a Pt-TiO2 NPs-deposited screen-printed carbon electrode
was also studied in detail. Such a highly sensitive and selective
sensor has been employed for noninvasive NO detection in human saliva.