Process “slimming” sword for universal organophosphorus pesticide detection: Development and validation of a single-probe-Cas12a integrated strategy

Given the irreversible neurotoxicity and high detection rates of chlorpyrifos (CPF) in agricultural products, developing sensitive and efficient sensors for CPF is highly urgent. Herein, we constructed a novel Locked-Activator-Cas12a (LAC) strategy with process “slimming” capability. It is predicated on a DNA activator that possesses two states acting as a crucial intermediary. The biosensor's efficacy is further enhanced by the copious generation of activators induced by the target, ensuring the unimpeded progression of the entire reaction, thereby facilitating precise and reliable CPF detection in complex matrices. Furthermore, we used bioinformatics resources, including AutodockVina, to explore the molecular interaction mechanism of CPF in binding to its aptamers through molecular docking simulations. Employing a two-step detection workflow, this approach is straightforward and readily scalable for detecting other organophosphorus pesticides by substituting the aptamer sequences. It is envisioned that these biosensors can be applied as a strategy robustness tool in agricultural samples, ultimately contributing to enhanced human health and well-being.