Advancing Biosensing and Imaging with DNA-Templated Metal Nanoclusters: Synthesis, Applications, and Future Challenges—A Review

Metal nanoclusters (MNCs) are emerging as a novel class of luminescent nanomaterials with unique properties, bridging the gap between individual atoms and nanoparticles. Among these, DNA-templated MNCs have gained significant attention due to the synergistic combination of MNCs’ properties (such as exceptional resistance to photostability, size-tunable emission, and excellent optical characteristics) with the inherent advantages of DNA, including programmability, functional modification, molecular recognition, biocompatibility, and water solubility. The programmability and biocompatibility of DNA offer precise control over the size, shape, and composition of MNCs, leading to tunable optical, electrical, and magnetic properties. This review delves into the complex relationship between DNA sequence, structure, and the resulting MNC properties. By adjusting parameters such as DNA sequence, length, and conformation, the size, morphology, and composition of the corresponding MNCs can be fine-tuned, enabling insights into how DNA structure influences the optical, electrical, and magnetic properties of MNCs. Finally, this review highlights the remarkable versatility and latest advancements of DNA-templated MNCs, particularly in biosensing and imaging, and explores their future potential to revolutionize biomedical applications.