A dendrimer enhanced CRISPR/Cas12a performance for the evaluation of acidogenic capacity in cariogenic bacteria

Abstract Dental caries, a highly prevalent global health issue, is fundamentally driven by the acidogenic metabolism of cariogenic bacteria such as Streptococcus mutans . Conventional approaches for assessing acidogenic capacity remain limited by complex operational requirements and insufficient sensitivity for point‐of‐care use. Herein, we engineer a CRISPR/Cas12a‐powered dendritic DNA nanostructure via hybridization chain reaction to construct a highly efficient signal amplification system. The designed activator strands self‐assemble into dendritic nano‐assemblies that enable multivalent immobilization of Cas12a‐crRNA complexes through programmable base pairing, resulting in a confined microdomain with dramatically enhanced local enzyme density and accelerated trans‐cleavage kinetics. The CRISPR/Cas dendritic aggregate enables high‐density immobilization of Cas12a, resulting in increased local enzyme concentration and enhanced catalytic cleavage efficiency. By integrating this system with a smart pH‐responsive molecular release mechanism, we further develop a paper‐based origami biosensor (CDEOB) for the on‐site and equipment‐free quantification of acidogenic pathogens. The biosensor achieves an ultra‐low detection limit of 98.1 CFU/mL in saliva and demonstrates excellent reliability across 101 clinical samples without pre‐amplification. This work provides a novel functional nucleic acid material design strategy and a versatile biosensing platform, highlighting substantial potential for early diagnosis of dental caries and other infectious diseases at the point of care.