A Robust Au−C≡C Functionalized Surface: Toward Real‐Time Mapping and Accurate Quantification of Fe²⁺ in the Brains of Live AD Mouse Models

Abstract

Described here is that Au-C≡C bonds showed the highest stability under biological conditions, with abundant thiols, and the best electrochemical performance compared to Au-S and Au-Se bonds. The new finding was also confirmed by theorical calculations. Based on this finding, a specific molecule for recognition of Fe²⁺ was designed and synthesized, and used to create a selective and accurate electrochemical sensor for the quantification of Fe²⁺ . The present ratiometric strategy demonstrates high spatial resolution for real-time tracking of Fe²⁺ in a dynamic range of 0.2-120 μM. Finally, a microelectrode array with good biocompatibility was applied in imaging and biosensing of Fe²⁺ in the different regions of live mouse brains. Using this tool, it was discovered that the uptake of extracellular Fe²⁺ into the cortex and striatum was largely mediated by cyclic adenosine monophosphate (cAMP) through the CREB-related pathway in the brain of a mouse with Alzheimer's disease.