Nanodiamond as a New Hyperpolarizing Agent and Its C-13 MRS

作者：Dutta Prasanta; Martinez Gary V; Gillies Robert J^*

来源：Journal of Physical Chemistry Letters, 2014, 5(3): 597-600.

DOI：10.1021/jz402659t

In this work, we have hyperpolarized carbonaceous nanoparticles (D approximate to 10 nm), that is, "nanodiamonds", with 1.1% C-13 (natural abundance) using dynamic nuclear polarization (DNP). The polarization buildup curve showed a signal enhancement with relative intensity up to 4700 at 1.4 K and 100 mW microwave power. C-13 magnetic resonance spectra (MRS) were obtained from the sample at 7 T, and the signal decayed with a T, of 55 +/- 3s. Notably, polarization was possible in the absence of added radical, consistent with previous results showing endogenous unpaired electrons in natural nanodiamonds. These likely contribute to the shorter T-1's compared to those of highly pure diamond. Despite the relatively short T-1, these observations suggest that natural nanodiamonds may be useful for in vivo applications.

• 出版日期2014-2-6