Toxicological and Immunological Evaluation of MXene Quantum Dots for Nanomedicine Applications

MXene quantum dots (MQDs) represent an emerging class of two-dimensional nanomaterials with unique physicochemical and biological properties relevant to nanomedicine. The synthesis and surface engineering of MQDs critically influence their size, composition, optical behavior, and subsequent biological interactions; thus, understanding these parameters is essential for rational material design. This review discusses current synthetic approaches and links them to biological outcomes including systemic compatibility, immune responses, biodegradation, and clearance. Available evidence suggests that properly engineered MQDs exhibit minimal acute toxicity, good hemocompatibility, and controlled degradation kinetics, supporting short-term biological persistence rather than chronic accumulation. Moreover, MQDs show context-dependent immunomodulatory effects such as regulation of T-cell activity and immune balance within tumor microenvironments. Mechanism-driven safety assessment beyond classical cytotoxicity is therefore required. By integrating material engineering, toxicological, and immunological insights, this review aims to delineate critical safety determinants and practical considerations for advancing MQDs toward reliable and clinically compliant nanomedicine applications.