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Dynamic nuclear polarization (DNP) transfers the large polarization of unpaired electrons to nuclei and thus significantly enhances the signal strength in nuclear magnetic resonance (NMR) spectroscopy. High frequency/field (140 GHz/5 T) DNP has been implemented in solid state NMR experiments using a nitroxide radical as the paramagnetic polarizing agent in a water:glycerol frozen solution. The ¹H and ¹³C NMR signal strengths of both the solvent and an amino acid solute have been enhanced by a factor of 185, which represents a reduction of ≳10² in sample size requirements or ≳10⁴ in signal acquisition time.