Hydrogen-Bonded Organic Framework Nanozyme with Multi-Enzyme Activity for Chemiluminescence Sensing of Acetylcholinesterase and Screening Its Inhibitors

Strong and persistent chemiluminescence (CL) is essential for enhancing the detection accuracy and reproducibility of CL-based analytical methods. In this study, we explored the synergistic effects of amino groups present on the surface of hydrogen-bonded organic framework (HOF-PyTTA, where PyTTA is denoted as 4,4′,4″,4‴-(pyrene-1,3,6,8-tetrayl)tetraaniline) materials and N-(4-aminobutyl-N-ethylisoluminol) (ABEI) for reducing gold nanoparticles (AuNPs) on the surface of HOFs. Additionally, we utilized the substantial specific surface area and abundant amino groups of HOFs to sequester Co²⁺ ions, resulting in the synthesis of HAACo material. The resulting HAACo exhibited remarkable peroxidase, oxidase, and catalase mimetic activities, enabling the luminol-H₂O₂ chemiluminescence system to maintain a glow-type CL phenomenon for more than 1 h. Subsequently, we developed a CL point-of-care testing (POCT) sensor that integrated the CL characteristics of HAACo with smartphone technology and 3D printing for the determination of acetylcholinesterase (AChE) activity in serum samples, as well as the screening for AChE inhibitors. The sensor demonstrated a linear detection range for AChE activity from 0.001 to 40 mU mL^–1, with a detection limit of 0.00057 mU mL^–1. The calculated IC₅₀ for the AChE inhibitor tacrine was found to be 21.9 nmol L^–1, indicating good selectivity and stability of the sensor. This work not only expands the applications of glow-type CL in biosensing but also enriches the utilization of HOF materials in analytical chemistry, paving the way for the development of multifunctional HOF-based materials for future applications.