Carbon Dots in Breast Cancer Theranostics: Structure–Property Relationships, Mechanisms, and Translational Insights

Abstract

Carbon dots (C‐dots) are an emerging class of carbon‐based nanomaterials that combine exceptional optical properties, tuneable surface chemistry, and biocompatibility, making them promising platforms for cancer theranostics. In breast cancer management, C‐dots have been investigated for integrated diagnostic and therapeutic functions, including fluorescence imaging, targeted drug delivery, photodynamic therapy (PDT), and photothermal therapy (PTT). This review summarises recent advances in C‐dot synthesis methods—covering both top‐down and bottom‐up strategies—with emphasis on how synthesis parameters and surface engineering influence optical performance, targeting specificity, and therapeutic efficacy. The structure–property relationships of C‐dots are critically examined in the context of breast cancer models, highlighting the roles of particle size, doping, functionalisation, and charge in modulating biodistribution and treatment outcomes. Mechanistic insights into C‐dot‐mediated PDT, PTT, and drug delivery are provided, alongside discussion of in vitro and in vivo evaluations. The challenges of long‐term toxicity assessment, large‐scale synthesis, and clinical translation are analysed, and future research opportunities are proposed, including stimuli‐responsive systems, hybrid nanostructures, and manufacturing pathways compliant with good manufacturing practice (GMP). By focusing on materials design principles and their biological implications, this review aims to guide the rational development of next‐generation C‐dots for effective and safe breast cancer theranostics.