Real-Time Polarimetry of Hyperpolarized <sup>13</sup>C Nuclear Spins Using an Atomic Magnetometer
K. Mouloudakis, Sven Bodenstedt, Marc Azagra, Morgan W. Mitchell, Irene Marco‐Rius, Michael C. D. Tayler
Abstract
We introduce a method for nondestructive quantification of nuclear spin polarization, of relevance to hyperpolarized spin tracers widely used in magnetic resonance from spectroscopy to in vivo imaging. In a bias field of around 30 nT we use a high-sensitivity miniaturized 87 Rb-vapor magnetometer to measure the field generated by the sample, as it is driven by a windowed dynamical decoupling pulse sequence that both maximizes the nuclear spin lifetime and modulates the polarization for easy detection. We demonstrate the procedure applied to a 0.08 M hyperpolarized [1– 13 C]-pyruvate solution produced by dissolution dynamic nuclear polarization, measuring polarization repeatedly during natural decay at Earth’s field. Application to real-time and continuous quality monitoring of hyperpolarized substances is discussed.