title: Application of ex situ dynamic nuclear polarization in studying small molecules.
abstract: Dynamic nuclear polarization (DNP) has become an attractive technique to boost the sensitivity of NMR experiments. In the case of ex situ polarizations two-dimensional (2D) spectra are limited by the short lifetime of the polarization after dissolution and sample transfer to a high field NMR magnet. This limitation can be overcome by various approaches. Here we show how the use of (13)C-labelled acetyl tags can help to obtain 2D-HMQC spectra for many small molecules, owing to a nuclear Overhauser enhancement between (13)C spins originating from the long-lived carbonyl carbon, which extends the lifetimes of other (13)C spins with shorter longitudinal relaxation times. We also show an alternative approach of using an optimized polarization matrix.
authors.affiliation: HWB-NMR, Institute of Cancer Studies, The University of Birmingham, Edgbaston, Birmingham, UK B15 2TT.
authors.forename: Christian
authors.initials: C
authors.lastname: Ludwig
authors.forename: Ildefonso
authors.initials: I
authors.lastname: Marin-Montesinos
authors.forename: Martin G
authors.initials: MG
authors.lastname: Saunders
authors.forename: Abdul-Hamid
authors.initials: AH
authors.lastname: Emwas
authors.forename: Zoe
authors.initials: Z
authors.lastname: Pikramenou
authors.forename: Stephen P
authors.initials: SP
authors.lastname: Hammond
authors.forename: Ulrich L
authors.initials: UL
authors.lastname: Günther
mesh_terms: D000085:Acetates / Q000737:chemistry; D000840:Anisoles / Q000737:chemistry; D002247:Carbon Isotopes / Q000737:chemistry; D002712:Chlorides / Q000737:chemistry; D009682:Magnetic Resonance Spectroscopy / Q000379:methods*
chemical_list: D000085:Acetates; D000840:Anisoles; D002247:Carbon Isotopes; D002712:Chlorides; C009760:mequinol; C081124:acetyl chloride