A sandwich FRET biosensor for lysozyme detection based on peptide-functionalized gold nanoparticles and FAM-labeled aptamer

Meiqing Liu; Hongyuan Zhuang; Yun Zhang; Yanwei Jia

doi:10.1016/j.talanta.2024.126226

A sandwich FRET biosensor for lysozyme detection based on peptide-functionalized gold nanoparticles and FAM-labeled aptamer

Talanta. 2024 May 9:276:126226. doi: 10.1016/j.talanta.2024.126226. Online ahead of print.

Authors

Meiqing Liu¹, Hongyuan Zhuang², Yun Zhang³, Yanwei Jia⁴

Affiliations

¹ State Key Laboratory of Structural Chemistry, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, Fuzhou, 350002, China; Xiamen Key Laboratory of Rare Earth Photoelectric Functional Materials, Xiamen Institute of Rare Earth Materials, Haixi Institute, Chinese Academy of Sciences, Xiamen, 361021, China; State-Key Laboratory of Analog and Mixed-Signal VLSI, Institute of Microelectronics, University of Macau, 999078, Macau, China. Electronic address: liumq@fjirsm.ac.cn.
² School of Clinical Medicine, Fujian Medical University, Fuzhou, 350122, China; Department of Clinical Laboratory, Xiamen Children's Hospital (Children's Hospital of Fudan University Xiamen Branch), Xiamen, 361006, China.
³ State Key Laboratory of Structural Chemistry, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, Fuzhou, 350002, China; Xiamen Key Laboratory of Rare Earth Photoelectric Functional Materials, Xiamen Institute of Rare Earth Materials, Haixi Institute, Chinese Academy of Sciences, Xiamen, 361021, China. Electronic address: zhangy@fjirsm.ac.cn.
⁴ State-Key Laboratory of Analog and Mixed-Signal VLSI, Institute of Microelectronics, University of Macau, 999078, Macau, China; Faculty of Science and Technology - ECE, University of Macau, 999078, Macau, China; MoE Frontiers Science Center for Precision Oncology, University of Macau, 999078, Macau, China. Electronic address: yanweijia@um.edu.mo.

PMID: 38754187
DOI: 10.1016/j.talanta.2024.126226

Abstract

Lysozyme (LYZ) plays a crucial role in the body's immune defense system. Monitoring LYZ levels can provide valuable insights into the diagnosis and severity assessment of various diseases. Traditionally, antibody-based sandwich assays are employed for LYZ detection, but they are often time-consuming and operationally complicated. In this research, a novel sandwich FRET biosensor was developed, which enables rapid detection of LYZ based on peptide-functionalized gold nanoparticles (pAuNPs) and FAM-labeled aptamer (Apt-FAM). Initially, a mixture of Apt-FAM and pAuNPs resulted in partial quenching of the Apt-FAM fluorescence emission through an inner filter effect (IFE), with negligible energy transfer because of the electrostatic repulsion between the negatively charged pAuNPs and Apt-FAM. The introduction of LYZ into the mixture drove the specific binding of Apt-FAM and pAuNPs to LYZ, facilitating the formation of a pAuNPs-LYZ-aptamer sandwich structure. The formation of this complex drew the pAuNPs and Apt-FAM into close enough proximity to enable FRET to occur, which in turn effectively quenched the fluorescence emission of FAM. The decrease in FAM fluorescence intensity was correlated with the increasing concentration of LYZ. Thus, a sandwich FRET biosensor was successfully developed for LYZ detection with a linear detection range of 0-1.75 μM and a detection limit of 85 nM. Additionally, the biosensor allowed visual detection of LYZ in a 96-well microplate, with a rapid response time of just 15 s. This study introduces a innovative sandwich FRET biosensor that combines aptamer and peptide recognition elements, offering a fast and antibody-free method for protein detection.

Keywords: FAM-Labeled aptamer (Apt-FAM); FRET biosensor; Lysozyme (LYZ); Peptide-functionalized gold nanoparticles (pAuNPs); Sandwich assay.