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Precise Spectral Overlap-Based Donor-Acceptor Pair for a Sensitive Traffic Light-Typed Bimodal Multiplexed Lateral
Sijie Liu1, Rui Shu1, Cong Zhao1
1College of Food Science and Engineering, Northwest A&F University, Yangling 712100, Shaanxi, China.
Insights
This study introduces a novel dual-response assay for detecting multiple targets in lateral flow immunoassays (LFIA). The new method enhances accuracy and sensitivity for detecting substances like ractopamine and clenbuterol.
Area of Science:
- Analytical Chemistry
- Biomedical Engineering
- Materials Science
Background:
- Multiplexed immunoassays, particularly lateral flow immunoassays (LFIA), are crucial for practical diagnostics.
- Current colorimetric-fluorescence bimodal LFIAs face challenges with indistinguishable targets and inefficient fluorescence quenching.
- Developing advanced LFIA platforms is essential for sensitive and accurate multi-analyte detection.
Purpose of the Study:
- To develop a precise spectral overlap-based donor-acceptor pair construction strategy for bimodal-type multiplexed LFIAs.
- To enhance the sensitivity and practicability of LFIA by overcoming limitations of existing methods.
- To propose a novel colorimetric-fluorescence dual-response assay for simultaneous detection of multiple analytes.
Main Methods:
- Designed a donor-acceptor pair by tuning nanocore size, nanoshell coating, and selecting distinct fluorescent donors.
- In situ coated Prussian blue nanoparticles (PBNPs) on gold nanoparticles (AuNPs) to create APNPs with tunable spectral properties.
- Integrated APNPs with competitive-type immunoreaction to develop a spatial separation traffic light-typed colorimetric-fluorescence dual-response assay (STCFD assay).
Main Results:
- The developed APNPs exhibited efficient fluorescence quenching, enhanced colloidal stability, and remarkable colorimetric intensity.
- The STCFD assay achieved high sensitivity with limits of detection of 0.013 ng mL⁻¹ for ractopamine and 0.152 ng mL⁻¹ for clenbuterol.
- The assay demonstrated superior performance due to the rational design of the spectral overlap-based donor-acceptor pair.
Conclusions:
- The proposed precise spectral overlap-based donor-acceptor pair construction strategy significantly improves LFIA performance.
- The STCFD assay offers a highly sensitive and practical solution for multiplexed detection.
- This work highlights the potential of rationally designed dual-response assays for point-of-care applications.
Abstract:
Bimodal-type multiplexed immunoassays with complementary mode-based correlation analysis are gaining increasing attention for enhancing the practicability of the lateral flow immunoassay (LFIA). Nonetheless, the restriction in visually indistinguishable multitargets induced by a single fluorescent color and difficulty in single acceptor ineffectual fluorescence quenching due to the various spectra of multiple different donors impede the further execution of colorimetric-fluorescence bimodal-type multiplexed LFIAs. Herein, the precise spectral overlap-based donor-acceptor pair construction strategy is proposed by regulating the size of the nanocore, coating it with an appropriate nanoshell, and selecting a suitable fluorescence donor with distinct colors. By in situ coating Prussian blue nanoparticles (PBNPs) on AuNPs with a tunable size and absorption spectrum, the resultant APNPs demonstrate efficient fluorescence quenching ability, higher colloidal stability, remarkable colorimetric intensity, and an enhanced antibody coupling efficiency, all of which facilitate highly sensitive bimodal-type LFIA analysis. Following integration with competitive-type immunoreaction, this precise spectral overlap-supported spatial separation traffic light-typed colorimetric-fluorescence dual-response assay (coined as the STCFD assay) with the limits of detection of 0.013 and 0.152 ng mL-1 for ractopamine and clenbuterol, respectively, was proposed. This work illustrates the superiority of the rational design of a precise spectral overlap-based donor-acceptor pair, hinting at the enormous potential of the STCFD assay in the point-of-care field.
