Quantum dot-based POCT systems: From multiplexed detection to cross-domain applications

Quantum dots (QDs) are positioned to revolutionize point-of-care testing (POCT), with their exceptional brightness, photostability, and multiplexing capabilities being leveraged to enable real-time, in-situ detection with practical utility. In this review, recent advances in QD-based sensing are systematically summarized, with emphasis placed on how precise control over synthesis and surface functionalization across key material families (e.g., chalcogenide QDs) has facilitated the development of a versatile analytical toolkit. Diverse transduction mechanisms, including fluorescence, colorimetric, electrochemiluminescence, photoelectrochemical, and chemiresistive sensing, are explored, and their deployment across biomedical diagnostics, environmental surveillance, and food safety is highlighted. Moving beyond a mere summary of progress, this review focuses on addressing the critical challenges that currently hinder the practical translation of QD-based sensing technologies. Key issues include the biotoxicity of heavy-metal-containing QDs, their limitation in complex sample matrices, performance gaps in emerging “green” QDs, and hurdles in device integration and data analysis. A coordinated strategy is therefore proposed, centered on greenification, intellectualization, and integration. It is envisioned that through advances in biocompatible materials, integration with portable platforms such as microfluidics and smartphones, and the incorporation of machine learning for intelligent signal processing, QDs will be propelled from laboratory tools into foundational, democratized technologies for next-generation POCT. The strategic framework presented here provides a clear roadmap to guide future research and translation efforts in QD-POCT.