Two-dimensional nuclear magnetic resonance spectroscopy with a microfluidic diamond quantum sensor

Area of Science:

• Quantum Sensing
• Spectroscopy
• Microfluidics

Background:

• Nitrogen-vacancy (NV) centers in diamond offer sensitive, non-inductive detection for nuclear magnetic resonance (NMR) spectroscopy.
• Current diamond NMR sensors face challenges in spectral resolution and sensitivity for analyzing picoliter volumes.

Purpose of the Study:

• To enhance spectral resolution and concentration sensitivity for multidimensional NMR analysis of picoliter samples using diamond quantum sensors.
• To develop a microfluidic platform for spatially separating polarization and detection phases in NMR experiments.

Main Methods:

• Utilized a microfluidic platform to spatially separate polarization and detection phases.
• Employed diamond quantum sensors for in-line NMR detection of liquid analytes.
• Performed two-dimensional correlation spectroscopy on samples within a ~40-picoliter detection volume.

Main Results:

• Achieved a spectral resolution of 0.65 ± 0.05 Hz, a significant improvement over previous diamond NMR studies.
• Demonstrated successful two-dimensional correlation spectroscopy on liquid analytes in a microfluidic device.
• Validated the use of diamond quantum sensors as effective in-line microfluidic NMR detectors.

Conclusions:

• Spatially separating polarization and detection phases in a microfluidic platform significantly enhances NMR spectral resolution and sensitivity.
• Diamond quantum sensors are a viable technology for in-line microfluidic NMR detection.
• This approach paves the way for mass-limited chemical analysis and single-cell biology applications.