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Published on: January 11, 2019
Highly selective excited state intramolecular proton transfer (ESIPT)-based superoxide probing
Dhiraj P Murale1, Hwajin Kim, Wan Sung Choi
1Molecular Logic Gate Laboratory, Department of Chemistry, Korea Advanced Institute of Science and Technology (KAIST), 373-1 Guseong-dong, Yuseong-gu, Daejeon, 305-701, Republic of Korea.
Organic Letters
|July 27, 2013
Summary
Two new fluorescent probes detect superoxide selectively using an excited state intramolecular proton transfer mechanism. This method offers a significant 60-fold increase in signal intensity for enhanced detection capabilities.
Area of Science:
- Chemistry
- Biochemistry
- Analytical Chemistry
Background:
- Superoxide is a key reactive oxygen species involved in various biological processes.
- Accurate detection of superoxide is crucial for understanding oxidative stress and related diseases.
- Existing detection methods may lack selectivity or sensitivity.
Purpose of the Study:
- To develop novel fluorescent probes for selective superoxide detection.
- To utilize the excited state intramolecular proton transfer (ESIPT) mechanism for enhanced signal generation.
- To achieve ratiometric and highly sensitive superoxide detection.
Main Methods:
- Synthesis of two novel fluorescent probe conjugates based on 2-(benzothiazol-2-yl)-phenol (HBT).
- Investigation of the probes' photophysical properties and response to superoxide.
- Application of the excited state intramolecular proton transfer (ESIPT) mechanism for signal amplification.
Main Results:
- The novel HBT-based probes demonstrated selective detection of superoxide.
- A significant 60-fold increase in fluorescence intensity was observed upon superoxide interaction.
- The probes exhibited ratiometric sensing capabilities, allowing for more accurate quantification.
Conclusions:
- The developed fluorescent probes offer a sensitive and selective method for superoxide detection.
- The ESIPT mechanism effectively enhances the fluorescence signal, improving detection limits.
- These probes hold potential for applications in biological and chemical research involving reactive oxygen species.
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