Recent developments in colorimetric immunoassays using nanozymes and plasmonic nanoparticles

Abstract

Enzyme-linked immunosorbent assay (ELISA) is a popular detection technique for the screening and diagnosis of diseases. The sensitivity of ELISA can be increased by the incorporation of nanoparticles. Through this article, we discuss the utilization of nanoparticles in ELISA. Nanoparticles possess an intrinsic biological peroxidase-like activity which allows it to act as an enzyme mimic for the development of an improved analysis method. Different nanoparticles (gold nanoparticles, silver nanoparticles, etc.) carry different peroxidase-mimic characteristics. Besides this, nanoparticles can also perform as a colorimetric substrate in ELISA where it gives a more prominent color change compared to the commonly used colorimetric substrate TMB. This article also focuses on the mechanisms behind this color change including aggregation, in situ nanoparticle growth, seeding, and etching.

Keywords:

• ELISA
• nanoparticles
• enzyme
• enzyme-mimic
• colorimetric
• localized surface plasmon resonance

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

The authors would like to acknowledge partly the financial support for the project given by Brunei Research Council of Negara Brunei Darussalam through Grant# BRC-10.