Anti-interference detection of antibiotic resistance genes via tetrahedral DNA framework-velcro capturing...

Methicillin-resistant Staphylococcus aureus (MRSA) is rapidly spreading worldwide. Concurrently, numerous antibiotic resistance genes (ARGs) have escaped into complex natural environments, particularly in water environment. Among these, mecA is one of the most prevalent ARGs identified in MRSA. Consequently, the development of robust analytical methods for detecting ARGs is critically important. This study effectively designed and constructed a tetrahedral DNA framework array termed "Velcro". By initiating the catalytic hairpin assembly (CHA) of the target loop through mecA, the "stickiness" of Velcro is stimulated, enabling efficient capture of, the composite of hydrogen-bonded organic frameworks (HOFs) with aggregation-induced electrochemiluminescence (AIECL) activity and co-reaction accelerator Ti₃C₂ MXene (TCM). Concurrently, the stable DNA framework can effectively withstand various environmental interferences, including bacterial invasion and enzymatic degradation, thereby enabling the sensitive detection and analysis of antibiotic resistance genes in complex environments. The linear range of the proposed ECL Biosensor for ARGs (mecA) detection was 0.01 pM to 10 nM, with a detection limit of 2.3 fM. This research proposes a novel approach for tracing this new type of genetic contamination and holds significant reference value for the scientific application of antibiotics.