posted on 2023-11-24, 00:17authored byAl-mahmnur Alam, Timsy Uppal, Md Shariful Islam, Manoranjan Misra, Subhash C Verma
This study showcases the creation of a biosensor strip
designed
for the rapid, precise, and highly sensitive electrochemical detection
of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). These
biosensor strips were crafted by affixing a monoclonal antibody (mAb)
specific to SARS-CoV-2 onto the surface of a commercially screen-printed
carbon electrode (SPCE) modified with polyaniline-titania nanotubes
(PANi-TNT). The transportable sensing device was constructed by pairing
the mAb functionalized strip with a portable potentiostat wirelessly
connected to either a Windows or Android device. Fast and specific
conjugation between spike protein of SARS-CoV-2 and immobilized anti-SARS-CoV-2
triggered a change in the charge and electron mobility in the biosensing
layer of the strip to produce detectable current during chronoamperometric
scanning in the presence of a phosphate buffer solution (PBS). The
excellent sensitivity and specificity of the sensor toward SARS-CoV-2
were detected as analytical analysis demonstrated linearity in the
range of 80 to 200 copies/μL with a limit of detection of 25.59
copies/μL from the dose–response and standard fitted
curve. Through experimental validation, the sensor strip’s
ability to specifically detect SARS-CoV-2 was established, distinguishing
it from human coronavirus-OC43 (HCoV-OC43), HCoV-NL63, HCoV-229E,
and adenovirus. The results from these tests indicate that these strips
possess the potential for the future creation of dependable and easily
transportable point-of-care diagnostic devices, enabling swift, sensitive,
and precise detection of SARS-CoV-2 in the saliva or nasopharyngeal
fluid of individuals infected with the virus.