Nanotechnology of carbon dots with their hybrids for biomedical applications: A review

In recent years, carbon-based nanomaterials (CBNs) have been widely used across various fields due to the benefit of optimizing their physicochemical properties via composite formation with diverse materials, leveraging their unique structures and properties. Among the different CBNs, carbon dots (CDs) have garnered increased attention owing to their exceptional optical properties, good biocompatibility, non-toxicity, and safety. In biomedicine, CDs have made significant contributions, particularly in disease diagnosis, treatment, and antibacterial applications. However, with the evolving challenges in medicine, CDs alone may not be sufficient for biomedical applications. To address this, researchers have enhanced the biomedical potential of CDs through their hybridization with other substances, forming complex structures. In this review, we will focus on the hybridization of CDs in combination with various types of substances. We aim to investigate the optimized properties of hybridized CD mixtures and compare their applications in biomedical fields with the singular use of CDs before hybridization, especially the exploration of carbon-dot hybrids (CDHs) in disease treatment. We summarize the advantages and challenges of CDHs in the biomedical field and discuss the potential of CDs in the future development of clinical medicine.