A selective turn-on fluorescent sensor for imaging copper in living cells

Area of Science:

• Chemical Biology
• Molecular Imaging
• Biochemistry

Background:

• Copper ions (Cu+) play critical roles in biological processes.
• Accurate detection of intracellular Cu+ is essential for understanding cellular functions.
• Existing sensors often lack selectivity or sensitivity for Cu+.

Purpose of the Study:

• To synthesize and characterize Coppersensor-1 (CS1), a novel fluorescent probe.
• To evaluate CS1's efficacy for selective and sensitive detection of intracellular Cu+.
• To demonstrate CS1's application in live-cell imaging of copper ions.

Main Methods:

• Synthesis of a BODIPY-based fluorescent sensor (CS1) with a thioether-rich receptor.
• Spectroscopic analysis to determine CS1's response to various metal ions.
• Confocal microscopy to assess CS1's membrane permeability and intracellular imaging capabilities.

Main Results:

• CS1 exhibits high selectivity and sensitivity for Cu+ over other metal ions, including Cu2+.
• The sensor demonstrates a 10-fold turn-on fluorescence response upon binding Cu+.
• CS1 is membrane-permeable and successfully monitors intracellular Cu+ levels in living cells.

Conclusions:

• CS1 is a novel, water-soluble, turn-on fluorescent sensor for intracellular Cu+.
• The BODIPY-based probe offers visible excitation/emission and high selectivity.
• CS1 provides a valuable tool for real-time monitoring of copper ions in biological systems.