As an excellent fluorescent nanomaterial, carbon quantum dots (CQDs) have the properties of small molecular weight, small particle size, high fluorescence stability, no optical flicker, wide excitation spectrum, continuous, long adjustable emission wavelength, good biocompatibility and low toxicity. At present, it has been widely used in biological detection, in vivo and in vitro imaging, drug delivery and diagnostic drugs. This review presents a broad overview of recent progress in synthesis, optical properties, and biomedical applications of CQDs. The synthesis methods of CQDs are first introduced, followed by an extensive discussion of its purification, surface functionalization methods and stability. Furthermore, the optical properties of CQDs are presented, with an emphasis on photoluminescence mechanism and the relationship between synthesis conditions and optical properties. This review's much focus is given to the biomedical applications of CQDs, including detection, imaging (in vivo and in vitro imaging) and drug delivery (targeted therapy, photodynamic and photothermal therapy, and immunological and gene therapy). Finally, we cover the key issues and future prospects/advances that CQDs still have to deal with in the biomedical sector as well as possible solutions.

碳量子点(CQDs)作为一种优良的荧光纳米材料，具有分子量小、粒径小、荧光稳定性高、无光学闪烁、激发光谱宽、连续、发射波长长可调、生物相容性好、毒性低等特点。目前已广泛应用于生物检测，体内外成像、药物输送和诊断药物。本综述全面概述了 CQD 在合成、光学特性和生物医学应用方面的最新进展。首先介绍了 CQD 的合成方法，然后对其纯化、表面功能化方法和稳定性进行了广泛讨论。此外，还介绍了 CQD 的光学特性，重点介绍了光致发光机制以及合成条件与光学特性之间的关系。这篇综述的重点是 CQD 的生物医学应用，包括检测、成像（体内和体外成像）和药物输送（靶向治疗、光动力和光热治疗以及免疫和基因治疗）。最后，我们介绍了 CQD 在生物医学领域仍然需要处理的关键问题和未来前景/进展以及可能的解决方案。