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Updated: Jul 1, 2026
09:15
Light Enhanced Hydrofluoric Acid Passivation: A Sensitive Technique for Detecting Bulk Silicon Defects
Published on: January 4, 2016
Unlocking HClO detection via an AIE "off-on-off" fluorescent switch.
Zhixin Zhang1, Xiangyi Wang1, Xianchuan Zeng1
1School of Pharmacy, Xianning Medical College, Hubei University of Science and Technology, Xianning 437100, PR China.
Summary
A new probe, TPE-ML, detects hypochlorous acid (HClO), a reactive oxygen species (ROS), with high sensitivity. This probe enables visual monitoring and real-time imaging in cells, advancing ROS detection methods.
Area of Science:
- Chemical Sensing
- Biomedical Diagnostics
- Reactive Oxygen Species Research
Background:
- Hypochlorous acid (HClO) is a critical reactive oxygen species (ROS) implicated in physiological processes and disease.
- Dysregulation of intracellular HClO levels is linked to inflammatory conditions and cancer.
- Accurate detection of HClO is vital for understanding its role in health and disease.
Purpose of the Study:
- To develop a novel aggregation-induced emission (AIE) probe, TPE-ML, for sensitive and selective detection of hypochlorous acid (HClO).
- To investigate the probe's fluorescence switching mechanism, AIE characteristics, and quantitative analytical capabilities.
- To demonstrate the probe's utility in food matrices and for real-time imaging of HClO in living cells.
Main Methods:
- Synthesis and characterization of the TPE-ML AIE probe.
- Fluorescence spectroscopy to assess sensitivity, selectivity, and "off-on-off" switching behavior.
- Solvent-dependent studies to confirm AIE properties and oxidation-induced fluorescence quenching.
- Quantitative analysis in food samples using the standard addition method.
- Live-cell imaging of HClO in 4T1 cells.
Main Results:
- TPE-ML exhibits a significant Stokes shift (~170 nm) and a low limit of detection (1.37 μM) for HClO.
- The probe demonstrates strong AIE characteristics, with a 15-fold fluorescence increase in high water fractions.
- Selective oxidation by HClO leads to fluorescence quenching, enabling detection.
- Quantitative analysis in fruits and vegetables yielded high recovery rates (98.3%-107.8%).
- Real-time imaging of HClO in living cells was successfully achieved.
Conclusions:
- TPE-ML is a novel AIE probe with excellent sensitivity and selectivity for hypochlorous acid detection.
- The probe's unique "off-on-off" fluorescence switching and AIE properties offer a new sensing mechanism for ROS.
- TPE-ML shows significant potential for on-site visual monitoring, quantitative analysis in food, and biomedical imaging of HClO.
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