Quantum dots enable next-generation POCT: Advanced material strategies enable a new era of portable, multiplexed sensing

QDs, semiconductor nanocrystals known for their exceptional brightness, photostability, and size-tunable optical properties, are poised to revolutionize POCT by transforming it from traditional qualitative methods toward highly sensitive, multifunctional, and intelligent systems. Through precise control over their size, composition, surface chemistry, and nanocomposite architectures, the optoelectronic properties of QDs can be finely tailored. This enables a versatile analytical toolkit powering diverse sensing mechanisms ranging from fluorescence and colorimetric to electrochemiluminescence, photoelectrochemical, and chemiresistive sensing.

A team led by Professor Jiatao Zhang from the Beijing Institute of Technology in Beijing, China, recently summarized recent advances in QD-based POCT, with a focus on chalcogenide QDs. They establish a clear “Material-Mechanism-Application-Challenge-Strategy” framework in their review. It details how QD performance can be customized through strategies like elemental doping, core-shell structure, surface engineering, and composite formation with materials such as metal-organic frameworks and hydrogels. These approaches are designed to meet the specific demands of different sensing modes, such as the high quantum yield required for fluorescence sensing or the efficient charge separation needed for photoelectrochemical sensing.

The team published their review in Nano Research on April 10, 2026.

“The advantages of quantum dots extend far beyond their bright and stable emission,” said Associate Professor Jiajia Liu, a corresponding author of the review. “We can perform atomic-scale ‘tailoring’ to engineer the most sensitive probes. For instance, by doping foreign ions we create new emission centers, or by constructing core-shell structures we protect the core and enhance luminescence. This allows us to target specific biomarkers, environmental pollutants, or food safety hazards.”

The review demonstrates the broad application prospects of QD-POCT across several critical fields. In biomedical diagnostics, QD-based sensors have enabled ultrasensitive detection of glaucoma biomarkers, cancer-related antigens, cardiac injury markers, and even circulating tumor cells at the single-cell level. For environmental monitoring, they are used to detect heavy metal ions in water and hazardous gases (e.g., NO₂) in the air. In food safety, QD technology allows for rapid screening of pathogens (e.g., Salmonella), biotoxins (e.g., aflatoxin), and pesticide residues.

However, transitioning from proof-of-concept demonstrations to scalable and robust POCT platforms faces several key challenges. Professor Jiatao Zhang, another corresponding author, highlighted the main bottlenecks: “First, the inherent biotoxicity of conventional QDs containing heavy metal ions like cadmium or lead necessitates the development of reliable encapsulation strategies or a shift towards ‘green’ alternatives like carbon dots or silicon QDs. Second, the stability of QDs in complex real-world matrices like blood, and the challenge of seamlessly integrating them into low-cost, automated microfluidic platforms and smartphone readers to create true ‘sample-in-answer-out’ intelligent devices, are pressing issues that need to be solved.”

To this end, the research team proposes a forward-looking development path centered on “Greenification, Intellectualization, and Integration.” “Greenification” involves developing high-performance QDs composed of biocompatible elements. “Intellectualization” refers to incorporating machine learning algorithms to intelligently interpret the high-dimensional data generated from multiplexed assays. “Integration” focuses on the deep fusion of QD sensing materials with portable device platforms.

“By collaboratively addressing these challenges, QD technology is poised to transcend its role as a specialized laboratory tool,” concluded Associate Professor Jiajia Liu. “It will emerge as a foundational technology for next-generation point-of-care testing, advancing personalized medicine, safeguarding environmental health and food safety, and ultimately making sophisticated sensing capabilities accessible to all.”

Other contributors include Zhiying He, Jiayu Ma, and Xiangyu Song from Beijing Institute of Technology in Beijing, China; and Zhenfei Wu, Di Wu, Li Zhao from Beijing Institute of Technology in Zhuhai, China.

This work was supported by by the National Natural Science Foundation of China (Nos. 52272186, 22375020, and 52072035).

DOI Link:

https://doi.org/10.26599/NR.2026.94908412

About Nano Research

Nano Research is a peer-reviewed, open access, international and interdisciplinary research journal, sponsored by Tsinghua University and the Chinese Chemical Society, published by Tsinghua University Press on the platform SciOpen. It publishes original high-quality research and significant review articles on all aspects of nanoscience and nanotechnology, ranging from basic aspects of the science of nanoscale materials to practical applications of such materials. After 18 years of development, it has become one of the most influential academic journals in the nano field. Nano Research has published more than 1,000 papers every year from 2022, with its cumulative count surpassing 8,000 articles. In 2025 InCites Journal Citation Reports, its 2025 IF is 9.4 (8.3, 5 years), and it continues to be the Q1 area among the four subject classifications. Nano Research Award, established by Nano Research together with TUP and Springer Nature in 2013, and Nano Research Young Innovators (NR45) Awards, established by Nano Research in 2018, have become international academic awards with global influence.