MRSA is an antibiotic resistant bacterium that poses a significant threat to the environment and human health due to its bioaccumulation and potential widespread contamination. The prompt and accurate identification of MRSA is essential for enhancing environmental monitoring and clinical management. Here, we develop a triple-helix molecular switch (THMS) fluorescent aptasensor for the determination of MRSA using Klenow fragment (KF)-assisted target recycling and Ribonuclease H (Rnase H)-powered DNA walker cascade amplification. In this method, the target opens the THMS by specifically binding ...