Table 2.

Summary of sample conditions and the optimized parameters of the DNP experiments.

Sample	Nanodiamonds	Microdiamonds	Pentacene-doped benzoic acid
Density of NV ${}^{-}$	$\mathrm{5.3}\times {\mathrm{10}}^{\mathrm{17}}$  cm ${}^{-\mathrm{3}}$ (3 ppm)	$\mathrm{8.9}\times {\mathrm{10}}^{\mathrm{17}}$  cm ${}^{-\mathrm{3}}$ (5 ppm)	–
Density of P1	$\mathrm{1.2}\times {\mathrm{10}}^{\mathrm{19}}$  cm ${}^{-\mathrm{3}}$ (70 ppm)	$\mathrm{4.6}\pm \mathrm{0.1}\times {\mathrm{10}}^{\mathrm{18}}$  cm ${}^{-\mathrm{3}}$ (26 ppm)	–
Density of pentacene	–	–	$\mathrm{2.6}\times {\mathrm{10}}^{\mathrm{18}}$  cm ${}^{-\mathrm{3}}$ (0.04 mol%)
Particle size	$\sim \mathrm{100}$  nm	$\sim \mathrm{500}$   $\mathrm{\mu }\mathrm{m}$	$<\mathrm{100}$   $\mathrm{\mu }\mathrm{m}$
$B_{\mathrm{sweep}}$ (mT)	(No DNP performed)	5	20
$t_{\mathrm{MW}}$ ( $\mathrm{\mu }\mathrm{s}$ )	(No DNP performed)	1250	30