Preparation, Characterization and Application of Optical Switch Probes

Area of Science:

• Molecular probes
• Biophysics
• Organic chemistry

Background:

• Optical switches are emerging molecular probes for biological applications.
• Nitrospirobenzopyran (NitroBIPS) molecules exhibit optically-driven reversible state transitions.
• These transitions are crucial for imaging and manipulating protein interactions.

Purpose of the Study:

• To detail the synthesis and characterization of NitroBIPS molecular switches.
• To describe methods for manipulating protein interactions using NitroBIPS.
• To demonstrate NitroBIPS imaging within living cells.

Main Methods:

• Synthesis and spectroscopic characterization of NitroBIPS and its conjugates.
• Utilizing optically-driven transitions between spiro (SP) and merocyanine (MC) states.
• Employing digital optical lock-in detection for fluorescence signal isolation.
• Investigating dipolar interactions on proteins and cellular imaging.

Main Results:

• NitroBIPS molecules undergo efficient, rapid, and reversible optical switching between SP and MC states.
• The merocyanine (MC) state exhibits fluorescence, serving as a readout for the switch's state.
• Optical perturbations generate distinct MC-fluorescence waveforms isolatable via lock-in detection.
• Successful manipulation of protein dipolar interactions and imaging of MC-state in living cells.

Conclusions:

• NitroBIPS represent a versatile class of molecular probes for advanced biological research.
• Their optical switching and fluorescence properties facilitate high-contrast imaging and protein interaction studies.
• The described protocols enable the application of NitroBIPS in cellular environments and for probing protein dynamics.