An Electrochemical Immunosensor Based on Carboxylated Graphene/SPCE for IgG-SARS-CoV-2 Nucleocapsid Determination.
Luciana de Souza FreireCamila Macena RuzoBárbara Batista SalgadoAriamna María Dip GandarillaYonny Romaguera BarcelayAna P M TavaresMaria Goreti Ferreira SalesIsabelle Bezerra CordeiroJaila Dias Borges LalwaniRobert Saraiva MatosHenrique Duarte da Fonseca FilhoSpartaco Astolfi-FilhoȘtefan ŢăluPritesh Jaychand LalwaniWalter Ricardo BritoPublished in: Biosensors (2022)
The COVID-19 pandemic has emphasized the importance and urgent need for rapid and accurate diagnostic tests for detecting and screening this infection. Our proposal was to develop a biosensor based on an ELISA immunoassay for monitoring antibodies against SARS-CoV-2 in human serum samples. The nucleocapsid protein (N protein) from SARS-CoV-2 was employed as a specific receptor for the detection of SARS-CoV-2 nucleocapsid immunoglobulin G. N protein was immobilized on the surface of a screen-printed carbon electrode (SPCE) modified with carboxylated graphene (CG). The percentage of IgG-SARS-CoV-2 nucleocapsid present was quantified using a secondary antibody labeled with horseradish peroxidase (HRP) (anti-IgG-HRP) catalyzed using 3,3',5,5'-tetramethylbenzidine (TMB) mediator by chronoamperometry. A linear response was obtained in the range of 1:1000-1:200 v/v in phosphate buffer solution (PBS), and the detection limit calculated was 1:4947 v / v . The chronoamperometric method showed electrical signals directly proportional to antibody concentrations due to antigen-antibody (Ag-Ab) specific and stable binding reaction.
Keyphrases
- sars cov
- respiratory syndrome coronavirus
- label free
- loop mediated isothermal amplification
- sensitive detection
- binding protein
- coronavirus disease
- protein protein
- room temperature
- gold nanoparticles
- walled carbon nanotubes
- quantum dots
- transcription factor
- carbon nanotubes
- high throughput
- dna binding
- mass spectrometry
- highly efficient
- liquid chromatography