New Persistent Luminescence Nanoprobe Enables Rapid On-Site Hydrogen Peroxide Detection

A new persistent luminescence nanoparticle-based optical probe developed by researchers at Chengdu University and Hefei University of Technology provides a breakthrough solution for detecting hydrogen peroxide (H₂O₂) with high sensitivity and without autofluorescence interference. The technology, detailed in a study published in Food Quality and Safety (DOI: 10.1093/fqsafe/fyaf040), offers both instrument-based quantitative detection and direct naked-eye visualization capabilities, making it particularly valuable for rapid on-site monitoring in resource-limited environments.

Hydrogen peroxide serves as a critical disinfectant and oxidizing agent across multiple industries including food processing, pharmaceuticals, and consumer products. However, excessive residues present significant health and safety concerns, potentially degrading nutrients, damaging tissues, causing gastrointestinal irritation, and increasing cancer risk. Conventional detection methods such as electrochemical sensing, fluorescence probing, and enzyme-based assays often require specialized equipment, continuous excitation, or complex sample preparation, while background autofluorescence in food and biological samples frequently compromises signal clarity and accuracy.

The newly developed PLNPs@MnO₂ probe consists of near-infrared ZnGa₂O₄:Cr persistent luminescence nanoparticles uniformly coated with a manganese dioxide shell. In its initial state, the MnO₂ layer effectively quenches luminescence through interfacial electron transfer, creating a turned-off signal. When exposed to H₂O₂ in mildly acidic conditions, MnO₂ rapidly reduces to Mn²⁺, interrupting the quenching pathway and immediately restoring bright red persistent luminescence. This mechanism achieves a detection limit of 0.079 μmol/L, significantly more sensitive than many conventional fluorescence or electrochemical sensors.

The technology demonstrates exceptional performance characteristics including high selectivity against common ions, sugars, amino acids, and proteins, along with excellent reproducibility and batch stability. Testing in real-world applications including bottled water, milk, and contact lens solutions yielded recovery rates ranging from 90.56% to 109.73%, confirming reliability across diverse sample matrices. The restored red luminescence can be visually recognized under UV illumination, enabling detection on flat plates or paper substrates without requiring sophisticated instruments.

The innovation addresses long-standing limitations in optical sensing by eliminating autofluorescence interference, which has traditionally hampered detection accuracy in complex food and biological matrices. By utilizing persistent luminescence instead of conventional fluorescence, the method produces clean, high-contrast signals without requiring continuous excitation. This autofluorescence-free detection strategy offers practical advantages for food safety monitoring, environmental inspection, and biomedical assays, with potential future applications including integration into smart packaging, wearable chemical sensors, and real-time contamination alert systems. The original research is accessible at https://doi.org/10.1093/fqsafe/fyaf040.

This technological advancement represents a significant step forward in supporting safer processing environments and improved consumer product quality assurance. By simplifying and accelerating H₂O₂ detection, the platform addresses critical needs across multiple sectors where rapid, reliable monitoring is essential for public health protection and quality control. The ability to perform sensitive detection without laboratory equipment makes the technology particularly transformative for field applications and developing regions where access to analytical instrumentation is limited.