Protein-Ligand Interaction Analyses with Nuclear Magnetic Resonance Spectroscopy Enhanced by Dissolution Triplet...

Area of Science:

• Biochemistry
• Analytical Chemistry
• Spectroscopy

Background:

• Solution-state nuclear magnetic resonance (NMR) spectroscopy is crucial for analyzing biomolecular interactions.
• Low sensitivity remains a significant limitation in traditional NMR methods.
• Enhanced sensitivity is needed for detailed studies of protein-ligand binding.

Purpose of the Study:

• To improve the sensitivity of solution-state carbon-13 (¹³C) NMR for observing intermolecular interactions.
• To develop a hyperpolarization technique for enhanced NMR analysis at room temperature.
• To apply the enhanced NMR method for pharmaceutical applications.

Main Methods:

• Utilized dynamic nuclear polarization (DNP) with photoexcited triplet electrons to hyperpolarize ¹³C-salicylic acid and benzoic acid eutectic crystals.
• Achieved a ¹³C nuclear polarization of 0.72 ± 0.07% after sample dissolution.
• Observed the binding of human serum albumin (HSA) to ¹³C-salicylate with significantly enhanced sensitivity.

Main Results:

• Demonstrated a sensitivity enhancement of several hundred times for protein-ligand interaction studies.
• Successfully observed intermolecular interactions under mild, room-temperature conditions.
• Applied the method to pharmaceutical NMR, detecting competitive drug binding via chemical shift changes.

Conclusions:

• Hyperpolarized ¹³C NMR significantly boosts sensitivity for biomolecular interaction analysis.
• The technique offers a powerful, enhanced tool for pharmaceutical drug discovery and development.
• This method provides a sensitive platform for studying molecular binding events in biological systems.