COF-Zincon dual signal amplification: A sensitive real-time electrochemical sensor for Zn2+ detection towards anxiety disorder diagnosis

Background In recent years, abnormal total zinc levels in serum have emerged as a robust indicator of anxiety disorder. However, measuring total zinc level requires sophisticated instrumentation and specialized personnel. Therefore, if the specific association between Zn 2+ in serum and anxiety disorder can be elucidated, it is promising to develop rapid and convenient diagnostic methods for anxiety disorder. In the field of Zn 2+ detection, Electrochemical detection has been investigated as a means to quantify Zn 2+ with precision, rapidity and cost-effectiveness. Nevertheless, most current electrochemical systems lack specificity. Results In this study, the relationship between anxiety disorder and serum Zn 2+ level was first elucidated, with research finding indicating that anxiety in mice correlated with a marked decline in serum Zn 2+ level. Subsequently, a sensitive and specific electrochemical sensor was developed to detect Zn 2+ with outstanding detection performance for the diagnosis of anxiety disorder. In this sensor, covalent organic framework material (COF Tp-Th ) was utilized to load a substantial amount of gold nanoparticles (AuNPs) via Au–N bonds to obtain COF Tp-Th -AuNPs material. AuNPs can enhance electrode catalysis and conductivity and served as a platform for subsequent material integration. Furthermore, a large quantity of Zincon reagent for specific recognition and detection of Zn 2+ was loaded onto the AuNPs through Au–S and Au–N bonds to improve electrode specificity, resulting in the construction of the target electrode modified material of COF Tp-Th -AuNPs-Zincon. Significance Long-range ordered COF Tp-Th can adsorb Zn 2+ through its rich tetradentate coordination ONNO chelation sites formed by Tp and Th, representing the primary signal amplification. Simultaneously, the abundant Zincon in COF Tp-Th -AuNPs-Zincon material with high affinity for the specific recognition and detection of Zn 2+ contributed to secondary signal amplification. This approach leads to a significant improvement in the detection performance of Zn 2+ and holds promise for providing robust support for the diagnosis and monitoring of anxiety disorder.