Design and Characterization of Hyperpolarized 15 N-BBCP as a H 2 O 2 -Sensing Probe.

Hydrogen peroxide (H 2 O 2 ) is a type of reactive oxygen species that regulates essential biological processes. Despite the central role of H 2 O 2 in pathophysiological states, available molecular probes for assessing H 2 O 2 in vivo are still limited. This work develops hyperpolarized 15 N-boronobenzyl-4-cyanopyridinium ( 15 N-BBCP) as a rationally designed molecular probe for detecting H 2 O 2 . The 15 N-BBCP demonstrated favorable physicochemical and biochemical properties for H 2 O 2 detection and dynamic nuclear polarization, allowing noninvasive detection of H 2 O 2 . In particular, 15 N-BBCP and the products possessed long spin-lattice relaxation times and spectrally resolvable 15 N chemical shift differences. The performance of hyperpolarized 15 N-BBCP was demonstrated both in vitro and in vivo with time-resolved 15 N-MRS. This study highlights a promising approach to designing a reaction-based 15 N-labeled molecular imaging agent for detecting oxidative stress in vivo.