Development of Nanobody-Displayed Whole-Cell Biosensors for the Colorimetric Detection of SARS-CoV‑2

• Published in: ACS applied materials & interfaces Vol. 15; no. 31; pp. 37184 - 37192
• Main Authors: He, Yawen, Xu, Zhiyuan, Kasputis, Tom, Zhao, Xue, Ibañez, Itati, Pavan, Florencia, Bok, Marina, Malito, Juan Pablo, Parreno, Viviana, Yuan, Lijuan, Wright, R. Clay, Chen, Juhong
• Format: Journal Article
• Language: English
• Published: United States American Chemical Society 09.08.2023
• Subjects: Biological and Medical Applications of Materials and Interfaces; biosensors; blood serum; Colorimetry; COVID-19 - diagnosis; detection limit; enzymatic reactions; genetically engineered microorganisms; Gold; Horseradish Peroxidase; human health; Humans; Metal Nanoparticles; nanogold; peroxidase; Saccharomyces cerevisiae; SARS-CoV-2; Severe acute respiratory syndrome coronavirus 2; Spike Glycoprotein, Coronavirus; virion; yeasts; colorimetric detection; SARS-CoV-2; nanobody; gold nanoparticle; whole-cell biosensor; engineered yeast
• ISSN: 1944-8244; 1944-8252; 1944-8252
• DOI: 10.1021/acsami.3c05900

The accurate and effective detection of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is essential to preventing the spread of infectious diseases and ensuring human health. Herein, a nanobody-displayed whole-cell biosensor was developed for colorimetric detection of SARS-CoV-2 spike proteins. Serving as bioreceptors, yeast surfaces were genetically engineered to display SARS-CoV-2 binding of llama-derived single-domain antibodies (nanobodies) with high capture efficiency, facilitating the concentration and purification of SARS-CoV-2. Gold nanoparticles (AuNPs) employed as signal transductions were functionalized with horseradish peroxidase (HRP) and anti-SARS monoclonal antibodies to enhance the detection sensitivity. In the presence of SARS-CoV-2 spike proteins, the sandwiched binding will be formed by linking engineered yeast, SARS-CoV-2 spike proteins, and reporter AuNPs. The colorimetric signal was generated by the enzymatic reaction of HRP and its corresponding colorimetric substrate/chromogen system. At the optimal conditions, the developed whole-cell biosensor enables the sensitive detection of SARS-CoV-2 spike proteins in a linear range from 0.01 to 1 μg/mL with a limit of detection (LOD) of 0.037 μg/mL (about 4 × 108 virion particles/mL). Furthermore, the whole-cell biosensor was demonstrated to detect the spike protein of different SARS-CoV-2 variants in human serum, providing new possibilities for the detection of future SARS-CoV-2 variants.