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Revealing Minor pH Changes of Mitochondria by a Highly Sensitive Molecular Fluorescent Probe
Jie Yuan1, Rong Peng1, Dan Cheng1
1State Key Laboratory of Chemo/Biosensing and Chemometrics, College of Chemistry and Chemical Engineering, Hunan University, Changsha, 410082, P. R. China.
Abstract:
Mitochondrial pH is an important factor associated with cellular metabolism and pathological states. Thus, sensitively monitoring its minor change was essential. However, it was challengeable due to the lack of suitable probes. Here, a mitochondria-targeted probe (NIR-OH-1) was synthesized. Based on the protonation/deprotonation of the hydroxy group and the assistance of carboxyl group on NIR-OH-1 molecular structure, a dramatic NIR activated signal was generated for sensing pH. Probe NIR-OH-1 displayed a good photo-stability and reversibility and could detect pH change without interference by other biologically active species. Importantly, NIR-OH-1 had an appropriate pKa value (7.77) and tiny acid-base transition range, which was allowed to map the small pH changes of cellular mitochondrial. Moreover, NIR-OH-1 was also successfully applied in real-time monitoring mitochondrial pH-related pathological events in living cells under different stimulation, demonstrating the prospect of its clinical application in accurate mitochondrial pH detection under related physiological and pathological conditions.
Insights
Researchers developed a novel mitochondria-targeted probe (NIR-OH-1) for sensitive detection of mitochondrial pH changes. This probe enables real-time monitoring of cellular metabolism and related pathological conditions.
Area of Science:
- Biochemistry
- Cell Biology
- Medical Diagnostics
Background:
- Mitochondrial pH is crucial for cellular metabolism and disease states.
- Accurate monitoring of mitochondrial pH is essential but challenging due to a lack of suitable probes.
- Existing methods lack the sensitivity and specificity required for real-time cellular analysis.
Purpose of the Study:
- To synthesize and characterize a novel mitochondria-targeted near-infrared (NIR) fluorescent probe for sensitive pH sensing.
- To evaluate the probe's performance in detecting subtle pH variations within cellular mitochondria.
- To demonstrate the probe's utility in real-time monitoring of mitochondrial pH during pathological events in living cells.
Main Methods:
- Synthesis of a mitochondria-targeted probe (NIR-OH-1) utilizing hydroxy and carboxyl groups for pH-dependent NIR signal generation.
- Characterization of the probe's photophysical properties, including photo-stability, reversibility, and pKa value (7.77).
- Application of the probe in living cells to monitor mitochondrial pH changes under various stimuli and pathological conditions.
Main Results:
- The synthesized probe NIR-OH-1 exhibited excellent photo-stability and reversibility.
- NIR-OH-1 demonstrated high sensitivity and specificity for detecting minor pH fluctuations in mitochondria without interference.
- The probe successfully mapped small mitochondrial pH changes and monitored pH-related pathological events in real-time within living cells.
Conclusions:
- The novel NIR-OH-1 probe provides a sensitive and reliable tool for accurate mitochondrial pH detection.
- Its ability to monitor pH dynamics in real-time offers significant potential for clinical applications in understanding and diagnosing pH-related diseases.
- This advancement facilitates deeper insights into cellular metabolism and pathological processes linked to mitochondrial pH alterations.
