Time resolved determination of anomeric rates of glucose-6-phosphate: success and limitations of dissolution-DNP

Hyperpolarization of biological samples by dynamic dissolution nuclear polarization (dDNP) has opened new perspectives for the time resolved observation of fast chemical processes by NMR, offering unprecedented sensitivity and temporal resolution. Among these processes, anomerization (the interconversion between the α and β forms of carbohydrates) is a fundamental, yet often neglected phenomenon, with implications for enzyme specificity and metabolic regulation. In this work, we study the kinetics of glucose-6-phosphate (G6P) anomerization by hyperpolarized NMR, exploiting dDNP to follow its evolution under various experimental conditions. This study highlights the ability of hyperpolarized NMR to quantify subtle dynamic equilibria, test kinetic models, and extract reliable rate parameters. More generally, it illustrates how this approach can shed light on fundamental molecular processes, difficult to capture in real time by conventional NMR techniques.