Yao_2026_Analyst__

Organophosphorus pesticides (OPs) pose serious risks to food safety and environmental health, but their rapid, sensitive detection is difficult. We developed TB-TD-COF, an urchin-like covalent organic framework, for acetylcholinesterase (AChE)-based electrochemical sensing. Synthesized via one-step room-temperature imine condensation, its thiophene-rich structure enhances electron transfer, and its microsphere morphology aids AChE immobilization and analyte transport. The TB-TD-AChE biosensor detects methyl parathion across a wide linear range (10(-10)-10(-6) g mL(-1)) with a low detection limit (2.13 x 10(-13) g mL(-1)), plus good reproducibility, stability, and performance in river water samples.