Quantum measurement enables single biomarker sensitivity in flow cytometry.

Area of Science:

• Quantum Optics
• Biophysics
• Analytical Chemistry

Background:

• Flow cytometry is crucial for analyzing cell populations.
• Current methods often lack single-molecule sensitivity for fluorophores.
• Quantum properties offer new avenues for enhanced detection.

Purpose of the Study:

• To develop an unambiguous experimental method for single-fluorophore sensitivity in flow cytometry.
• To utilize quantum measurements for detecting individual biomarkers.
• To enable precise calibration of flow cytometry measurements.

Main Methods:

• Employing quantum measurement based on the second-order coherence function.
• Utilizing single-photon emitters and their quantum properties.
• Analyzing optical signals from individual biomarkers in a flow cytometer.

Main Results:

• Achieved unambiguous single-fluorophore sensitivity in flow cytometry.
• Demonstrated detection of individual biomarkers using quantum coherence.
• Established a 'photons-to-moles' calibration for the measurement modality.

Conclusions:

• Quantum properties of single-photon emitters enable unprecedented sensitivity in flow cytometry.
• This method allows for rapid detection, enumeration, and sorting of single fluorophores.
• Provides a foundation for advanced biomarker quantification and analysis.