Flipper dendrimers

Area of Science:

• Biophysics
• Supramolecular Chemistry
• Cell Biology

Background:

• Fluorescent flipper probes are used to image forces in cell membranes.
• Existing probes suffer from phototoxicity, limiting their application.
• Significant performance improvements have been lacking since their initial design.

Purpose of the Study:

• To develop improved fluorescent probes that address the phototoxicity issue.
• To enhance fluorescence intensity and maintain responsiveness to membrane tension.
• To enable longer-term monitoring of cellular processes.

Main Methods:

• Introduction of flipper dendrimers, large peptide dendrimers inspired by inverted cones.
• Engineering probe integration into the cellular environment using supramolecular chemistry.
• Modulating fluorescence lifetime and membrane targeting via peptide dendrimers and hydrophobic interfacers.

Main Results:

• Flipper dendrimers exhibit significantly stronger fluorescence in cells compared to existing probes.
• Imaging can be performed at approximately one order of magnitude lower laser power.
• Reduced phototoxicity allows for extended monitoring of biological dynamics.
• Demonstrated control over probe orientation, distribution, and internalization.

Conclusions:

• Flipper dendrimers represent a breakthrough in fluorescent probe technology by minimizing phototoxicity.
• This supramolecular chemistry approach enhances probe performance by optimizing environmental integration.
• The strategy is broadly applicable for improving other molecular probes.