Mitochondria-targeting biocompatible fluorescent BODIPY probes

Area of Science:

• Biochemistry
• Molecular Biology
• Medical Imaging

Background:

• Elevated mitochondrial membrane potential (MMP) is a hallmark of diseases like cancer and cardiovascular conditions.
• Accurate monitoring of MMP is vital for assessing mitochondrial function and disease progression.
• Development of sensitive fluorescent probes is crucial for effective mitochondrial imaging.

Purpose of the Study:

• To design, synthesize, and characterize novel BODIPY dyes (BODIPY-Mito-n) for mitochondria-targeted fluorescence imaging.
• To evaluate the photophysical properties, biocompatibility, and MMP sensitivity of these new probes.
• To identify lead compounds for advanced mitochondrial diagnostics.

Main Methods:

• Synthesis of six BODIPY-Mito-n analogues under mild conditions.
• Photophysical characterization including fluorescence quantum yields in aqueous environments.
• Biological evaluation of probe localization, biocompatibility (IC50), and MMP sensitivity using fluorescence microscopy.
• Assessment of mitochondrial targeting efficiency using Pearson's correlation coefficients (PCC).

Main Results:

• Synthesized BODIPY-Mito-n dyes exhibited high fluorescence quantum yields (0.59–0.72) at physiological pH.
• Incorporation of PEG chains enhanced probe biocompatibility (BODIPY-Mito-6, IC50 > 50 μM).
• All probes showed high MMP-sensitive mitochondrial localization (PCC 0.76–0.96).
• BODIPY-Mito-2 and BODIPY-Mito-6 demonstrated significant emission intensity decreases (62% and 75%) upon MMP depolarization.

Conclusions:

• The BODIPY-Mito-n series represents effective mitochondria-targeted fluorescent probes.
• BODIPY-Mito-6 offers superior MMP sensitivity and biocompatibility, indicating its potential for future mitochondrial imaging applications.
• These findings pave the way for developing advanced diagnostic tools for mitochondrial dysfunction.