SABRE Acethydrazide as a Co-Substrate Agent for Quantitative Analysis of Submicromolar N-Heterocyclic Compounds Using
Quy Son Luu1, Quynh Thi Nguyen2, Seokki Yun2
1Hanyang Institute for Precision Therapeutics, Department of Bionano Technology, Center for Bionano Intelligence Education and Research, Hanyang University, Ansan 15588, South Korea.
Analytical Chemistry
|January 12, 2026
Summary
Acethydrazide (ACH) enhances Signal Amplification by Reversible Exchange (SABRE) hyperpolarization, enabling detection of N-heterocycles at submicromolar levels. This breakthrough improves sensitivity for NMR applications.
Area of Science:
- Nuclear Magnetic Resonance (NMR) Spectroscopy
- Hyperpolarization Techniques
- Catalysis
Background:
- Signal Amplification by Reversible Exchange (SABRE) hyperpolarization enhances NMR signals.
- Current SABRE methods face sensitivity limitations for detecting analytes at micromolar or lower concentrations.
Purpose of the Study:
- To introduce acethydrazide (ACH) as a novel co-substrate to improve SABRE hyperpolarization efficiency.
- To enable the detection of aromatic N-heterocycles at submicromolar concentrations using SABRE.
Main Methods:
- Utilized acethydrazide (ACH) as a co-substrate in SABRE hyperpolarization.
- Employed non-hydrogenative parahydrogen-induced polarization (nhPHIP) experiments.
- Performed density functional theory (DFT) calculations to elucidate catalyst stabilization.
Main Results:
- ACH significantly enhances SABRE hyperpolarization efficiency by stabilizing iridium catalysts.
- Achieved detection of aromatic N-heterocycles at submicromolar concentrations (below 1.0 μM) in a single scan.
- Demonstrated a 422-fold enhancement factor and 2.52 au signal-to-noise ratio for nicotinamide at 0.75 μM.
Conclusions:
- Acethydrazide (ACH) is a novel co-substrate that overcomes sensitivity limitations in SABRE hyperpolarization.
- The improved SABRE method with ACH expands potential applications in biological and industrial settings.
- Detection of analytes at micromolar concentrations is now feasible, broadening NMR's utility.
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