Rationally Designed Ionically Conductive Metal‐Organic Frameworks for Ultrasensitive Methamphetamine Analogs Sensor

Abstract Achieving convenient, sensitive, low‐cost, and non‐contact detection of trace addictive drugs is a challenging problem. Herein, a novel ionically conductive metal‐organic framework (IC‐MOFs) is designed through a controlled interface assembly strategy. The active metal anions are incorporated into the layered MOFs with a porous structure, forming charge carriers that served as effective adsorption/binding sites for N‐methylphenethylamine (MPEA), a crucial simulator of addictive drugs. The in situ integrated Zn₃(HHTP)₂‐MOF sensor device designed in this study demonstrated real‐time detection of sub‐ppb level MPEA at room temperature, with an exceptionally low theoretical detection limit of 20 ppt. The overall sensing performance of this sensor surpassed all previously reported chemical sensors for detecting methamphetamine. The Zn₃(HHTP)₂‐MOF sensor exhibited outstanding selectivity, rapid response time (ca. 5 s), excellent long‐term stability, amenable miniaturization, and device consistency. The device successfully passed dual 85 test (500 h at 85 °C and 85% of humidity), which is rarely report previously. Density functional theoretical calculations (DFT) and spectral characterization confirmed that the prominent selectivity of Zn₃(HHTP)₂‐MOF toward MPEA is attributed to the strong binding ability. The general and straightforward strategy provides brand‐new route to exploiting smart sensors for drug prevention and surveillance.