Functional Zonation Strategy of Heterodimer Nanozyme for Multiple Chemiluminescence Imaging Immunoassay

Abstract

Although nanozymes with intrinsic enzyme-like characteristics have aroused great interest in the biosensing field, the challenge is to keep high enzyme-like activity of the nanozyme after the modification of biomolecules onto nanozymes. Herein, a functional zonation strategy of a heterodimer nanozyme was proposed to tackle the challenge and further construct a multiple chemiluminescence (CL) imaging immunoassay. Here Fe 3 O 4 -Au as a heterodimer nanozyme model was divided into two zones, in which Fe 3 O 4 nanoparticles (NPs) were regarded as a nanozyme zone and AuNPs were defined as an antibody immobilization zone. A signal amplification probe (Fe 3 O 4 -Au-Ab 2 ) was prepared by modifying the secondary antibody (Ab 2 ) on AuNPs of the Fe 3 O 4 -Au heterodimer owing to the Au−S bond. The exposed Fe 3 O 4 of the Fe 3 O 4 -Au-Ab 2 probe shows very high peroxidase-like activity and can efficiently catalyze H 2 O 2 -luminol to produce strong CL imaging signals for multiple antigens detection. Using chicken interleukin-4 (ChIL-4) and chicken gamma interferon (ChIFN-γ) as models, the proposed CL imaging immunoassay shows wide linear ranges (0.005−0.10 ng/mL for both ChIL-4 and ChIFN-γ) and low detection limits (0.58 pg/mL for ChIL-4, 0.47 pg/mL for ChIFN-γ) with the characteristics of high sensitivity, high specificity, and good stability. This work provides a promising functional zonation concept for nanozymes to construct new types of nanozyme probes for immunoassay of multiple biomolecules.

Rational Integration of Nanozyme Probe and Smartphone Device for On‐Site Analysis

“…Subsequently, enzymatic substrate and luminescent substrate are added to trigger the light emission which can be imaged by cameras. [61,62] Although the used natural enzymes possess powerful signal amplification capability, their structural instability and high cost remain a challenge. Thanks to the high stability and low cost, as well as good catalytic ability, nanozymes show the potential as a satisfactory substitute for natural enzymes in CLIA.…”

In Situ Electrospinning MOF-Derived Highly Dispersed α-Cobalt Confined in Nitrogen-Doped Carbon Nanofibers Nanozyme for Biomolecule Monitoring

“…The rapid and accurate detection of biomolecules is crucial to diagnose, track, and prevent varieties of diseases. − Recently, the colorimetric assay has received considerable attention for detecting different biological molecules owing to its easy operation, high efficiency, and “naked eye” visual detection. − It is worth mentioning that nanozymes have been widely studied as substitutes for natural enzymes in colorimetric assays, which can be attributed to the high enzyme-like activity, easy preparation, and strong stability in extreme conditions of nanozymes. − However, developing nanozymes with highly dispersed active sites and high enzyme-mimicking catalytic activities as well as robust structures for colorimetric biosensing diverse biomolecules still remains a substantial challenge. Metal–organic frameworks (MOFs) are porous organic–inorganic coordination materials with a large number of active sites that have been utilized as nanozymes in the fields of biotherapy, antibacterial, biosensors, and pollutant degradation. , Recently, Co nanoparticles derived from MOF with excellent enzyme-like activities have attracted considerable attention in many fields .…”

Accelerating the Phosphatase-like Activity of Uio-66-NH2 by Catalytically Inactive Metal Ions and Its Application for Improved Fluorescence Detection of Cardiac Troponin I

“…Compared with natural enzymes, nanozymes possess impressive characteristics such as high stability, low cost, ability to be recycled, and ease of making multifunctional . Recently, nanozymes have attracted increasing interest in the field of immunoassay since they have the potential to replace natural enzymes as enzyme labels to establish various immunoassays. − Although nanozymes can mimic the catalysis of natural enzymes, nanozymes exhibit much lower catalytic activities than natural enzymes. Obviously, this is a major challenge for nanozymes, which limits the sensitivities of the nanozyme-based immunoassays.…”