Engineering DNA-Nanozyme Interfaces for Rapid Detection of Dental Bacteria

Engineering biological interfaces represents a powerful means to improve the performance of biosensors. Here, we developed a DNA-engineered nanozyme interface for rapid and sensitive detection of dental bacteria. We employed DNA aptamer as both molecular recognition keys and adhesive substrates to functionalize the nanozyme. Utilizing different immobilization strategies and DNA designs, a range of DNA nanoscale biointerfaces were constructed to modulate enzymatic and biological properties of the nanozyme systems. These functional biointerfaces improved the accessibility of bacteria to the nanozyme surface, providing large signal change range at optimal DNA probe density. The DNA-functionalized nanozymes demonstrate a rapid, label-free, and highly sensitive direct colorimetric detection of Streptococcus mutans, with a detection limit of 12 CFU mL^-1, as well as excellent discrimination from other dental bacteria. We demonstrate the use of this biological nanointerface for identifying dental bacteria in salivary samples, showing its potential in clinical prevention and diagnosis of dental diseases.