Dual-Function Janus Nanozymes for Performance Evaluation and Application in a Surrogate Virus Neutralization Test...

Area of Science:

• Nanotechnology
• Biomedical Engineering
• Materials Science

Background:

• Nanozymes offer advantages over natural enzymes in biosensing due to stability, cost, and performance.
• Comparing nanozyme performance is challenging due to dependencies on shape, size, and surface functionalization.

Purpose of the Study:

• To develop a method for fabricating nanozymes with identical physicochemical properties but varying compositions for quantitative performance comparison.
• To identify the optimal nanozyme for biosensing applications.
• To apply the optimized nanozyme in detecting neutralizing antibodies against SARS-CoV-2.

Main Methods:

• Fabrication of double-layered Janus nanozymes with a catalytic layer and a gold quantification layer.
• Quantitative comparison of nanozymatic activities using kinetic parameters.
• Application of the best-performing nanozyme in a surrogate virus neutralization test for SARS-CoV-2 antibodies.

Main Results:

• Synthesized Janus nanozymes allowed the first quantitative comparison of nanozymatic activities.
• The iridium-gold (Ir-Au) nanozyme demonstrated the highest catalytic performance.
• The Ir-Au nanozyme-based assay detected SARS-CoV-2 neutralizing antibodies with a limit of detection of 2 pg/mL and showed selectivity for MERS-CoV.

Conclusions:

• The developed Janus nanozymes enable quantitative nanozyme activity comparisons.
• The Ir-Au nanozyme is a highly effective catalyst for biosensing applications.
• This approach offers a cost-effective, rapid, and sensitive diagnostic tool for viral neutralizing antibody detection.