Spacer Matters: All-Peptide-Based Ligand for Promoting Interfacial Proteolysis and Plasmonic Coupling

Spacer Matters: All-Peptide-Based Ligand for Promoting Interfacial Proteolysis and Plasmonic Coupling

Nano Letters

10.1021/acs.nanolett.2c03052

http://dx.doi.org/10.1021/acs.nanolett.2c03052

Zhicheng Jin, Chuxuan Ling, Yi Li, Jiajing Zhou, Ke Li, Wonjun Yim, Justin Yeung, Yu-Ci Chang, Tengyu He, Yong Cheng, Pavla Fajtová, Maurice Retout, Anthony J O’Donoghue, Jesse V. Jokerst

Mechanical Engineering, General Materials Science, General Chemistry, Condensed Matter Physics, Bioengineering

08 November 2022

Jin, Z., Ling, C., Li, Y., Zhou, J., Li, K., Yim, W., Yeung, J., Chang, Y.-C., He, T., Cheng, Y., Fajtová, P., Retout, M., O’Donoghue, A. J., & Jokerst, J. V. (2022). Spacer Matters: All-Peptide-Based Ligand for Promoting Interfacial Proteolysis and Plasmonic Coupling. Nano Letters, 22(22), 8932–8940. https://doi.org/10.1021/acs.nanolett.2c03052

Plasmonic coupling via nanoparticle assembly is a popular signal-generation method in bioanalytical sensors. Here, we customized an all-peptide-based ligand that carries an anchoring group, polyproline spacer, biomolecular recognition, and zwitterionic domains for functionalizing gold nanoparticles (AuNPs) as a colorimetric enzyme sensor. Our results underscore the importance of the polyproline module, which enables the SARS-CoV-2 main protease (Mpro) to recognize the peptidic ligand on nanosurfaces for subsequent plasmonic coupling via Coulombic interactions. AuNP aggregation is favored by the lowered surface potential due to enzymatic unveiling of the zwitterionic module. Therefore, this system provides a naked-eye measure for Mpro. No proteolysis occurs on AuNPs modified with a control ligand lacking a spacer domain. Overall, this all-peptide-based ligand does not require complex molecular conjugations and hence offers a simple and promising route for plasmonic sensing other proteases.

Publisher Copyright

There was no specific funding for the research done

This document is the Accepted Manuscript version of a Published Work that appeared in final form in Nano Letters, copyright © American Chemical Society after peer review and technical editing by the publisher. To access the final edited and published work see doi.org/10.1021/acs.nanolett.2c03052

https://oar.a-star.edu.sg/communities-collections/articles/19368

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