Optically hyperpolarized Nano-Diamond MRI at Room Temperature

Diamond nano-particles with surface functionalization nanoparticles for biomedical applications such as targeting, sub-cellular tracking, and non-toxic therapy [1]. The versatility of nano-diamond has motivated the development of new diamond-based imaging agents that will ‘light up’ under MRI to produce a bright field contrast image. Conventional Dynamic Nuclear Polarization mechanism which has been successfully demonstrated in diamond to hyperpolarize ¹³C nuclei, has to rely on high fields and cryogenic temperatures. Here we demonstrate a room temperature hyperpolarized nano-diamond ¹³C imaging with an enhancement of ~600 against 7T thermal polarization[2]. We were also able to achieve back ground suppression in magnetic resonance imaging with the ability of on demand controlling the sign of the hyperpolarization signal. Furthermore, combing both MRI and optical imaging of powder diamond, we present a new dual-modality nano-diamond imaging approach with orders of magnitude SNR enhancement.

[1] Cassidy, M. C., et al. "In vivo magnetic resonance imaging of hyperpolarized silicon particles." Nature nanotechnology 8.5 (2013): 363.
[2] Ajoy, Ashok, et al. "Orientation-independent room temperature optical 13C hyperpolarization in powdered diamond." Science Advances 4.5 (2018): eaar5492.