DNAsn

DNAsn is an acronym for DNA-based nanosensor, a class of nanoscale devices that use DNA as the primary sensing scaffold and transduction medium. In typical designs, DNAsns rely on DNA aptamers or DNAzymes to recognize a specific target, or on DNA origami scaffolds to arrange functional elements with nanometer precision. Target binding or catalytic activity induces a conformational change or strand-displacement reaction that translates molecular recognition into a measurable signal, such as fluorescence, electrochemical current, or a color change.

Construction and operation: A DNAsn comprises a recognition module (for example, an aptamer or DNAzyme), a transduction module (fluorophores, quantum dots, or electrode surfaces), and a DNA scaffold that organizes these components. Readout mechanisms commonly exploit changes in fluorescence resonance energy transfer, signal quenching, or redox activity. Some designs incorporate amplification motifs to lower detection limits, enhancing sensitivity in complex samples.

Applications and variants: DNAsns have potential applications in medical diagnostics, environmental monitoring, and basic research. Variants include fluorescent DNAsns for real-time imaging, electrochemical DNAsns for point-of-care testing, and multiplexed versions capable of detecting several targets simultaneously. They can be adapted to detect ions, small molecules, proteins, or nucleic acids.

Limitations and outlook: Challenges include ensuring stability in physiological conditions, minimizing non-specific interactions, and reducing production costs. Ongoing work focuses on device integration, robustness in real-world samples, and regulatory validation to enable broader deployment.