In situ formation of boronic acid-based covalent organic frameworks for specific and ultra-sensitive electrochemical assay of glycosylated amyloid-beta proteins

Talanta. 2024 Dec 19:285:127435. doi: 10.1016/j.talanta.2024.127435. Online ahead of print.

Abstract

Alzheimer's disease (AD) significantly impacts the well-being of older people around the world. However, the accurate detection of glycosylated amyloid-beta (Aβ) proteins, which serve as important biomarkers for AD, remains challenging due to their extremely low levels. To address these issues, we proposed a method for fabricating a flexible and stable sensor platform based on an innovative boronic acid-based covalent organic framework COF-B(OH)2. After in situ formation on carbon cloth (CC) by facile interfacial perturbation, this CC-based COF substrate could further serve as an electrochemical platform for detecting glycosylated-Aβ16 via molecular interactions. The substrate offers abundant molecular recognition sites, a large specific surface area, and excellent electrical conductivity. Furthermore, poly(thymine)-templated copper nanoparticles (CuNPs) linked to the aptamer of glycosylated-Aβ16 were employed as electrochemical probes, providing an amplified signal. The proposed assay for the detection of glycosylated-Aβ16 proteins demonstrated a wide detection range of 5-1800 pg/mL, with an ultralow detection limit of 0.32 pg/mL and high stability. This research offers novel insights into the developing electrochemical biosensors for analyzing glycosylated protein, leveraging advanced COF-B(OH)2 materials.

Keywords: Boronic acid-based COF; Copper nanoparticles; Electrochemical sensor; Glycosylated amyloid-beta peptides.