Abstract
Electrochemical immuno-biosensors are one of the most promising approaches for accurate, rapid, and quantitative detection of protein biomarkers. The two-working electrode strip is employed for creating a self-supporting system, as a tool for self-validating the acquired results for added reliability. However, the realization of multiplex electrochemical point-of-care testing (ME-POCT) requires advancement in portable, rapid reading, easy-to-use, and low-cost multichannel potentiostat readers. The combined multiplex biosensor strips and multichannel readers allow for suppressing the possible complex matrix effect or ultra-sensitive detection of different protein biomarkers. Herein, a handheld binary-sensing (BiSense) bi-potentiostat was developed to perform electrochemical impedance spectroscopy (EIS)-based signal acquisition from a custom-designed dual-working-electrode immuno-biosensor. BiSense employs a commercially available microcontroller and out-of-shelf components, offering the cheapest yet accurate and reliable time-domain impedance analyzer. A specific electrical board design was developed and customized for impedance signal analysis of SARS-CoV-2 nucleocapsid (N)-protein biosensor in spiked samples and alpha variant clinical nasopharyngeal (NP) swab samples. BiSense showed limit-of-detection (LoD) down to 56 fg/mL for working electrode 1 (WE1) and 68 fg/mL for WE2 and reported with a dynamic detection range of 1 pg/mL to 10 ng/mL for detection of N-protein in spiked samples. The dual biosensing of N-protein in this work was used as a self-validation of the biosensor. The low-cost (∼USD$40) BiSense bi-potentiostat combined with the immuno-biosensors successfully detected COVID-19 infected patients in less than 10 min, with the BiSense reading period shorter than 1.5 min, demonstrating its potential for the realization of ME-POCTs for rapid and hand-held diagnosis of infections.
Keywords: Bi-potentiostat; Electrochemical biosensing; Point-of-care; Rapid tests; SARS-CoV-2.
【저자키워드】 SARS-CoV-2., point-of-care, electrochemical biosensing, Rapid tests, Bi-potentiostat, 【초록키워드】 SARS-CoV-2, Biomarkers, reliability, variant, Diagnosis, biosensor, Protein, point-of-care, infections, nasopharyngeal, Rapid, Alpha, multiplex, Quantitative, Analysis, components, complex, advancement, swab samples, SARS-CoV-2 nucleocapsid, N-protein, acquisition, shelf, electrode, matrix effect, was used, approach, reported, added, less, electrical, COVID-19 infected patient, creating, 【제목키워드】 platform, COVID-19 infected patient,