title: NMR difference spectroscopy with a dual saddle-coil difference probe.
abstract: A new difference probe for nuclear magnetic resonance (NMR) spectroscopy is presented. The difference probe uses two saddle-shaped coils to excite and detect two samples simultaneously. The samples are held in a specially modified 3-mm NMR tube with an Ultem plastic disk to separate the samples. The probe's resonant circuit contains two crossed diodes that passively switch the relative phase of each coil during the NMR experiment. The result is a difference spectrum from the two samples. The degree of cancellation of common signals was determined to be approximately 90%, and the application of the probe to relaxation-edited difference spectroscopy for identifying protein-ligand interactions was demonstrated using glutathione and glutathione S-transferase binding protein.
authors.affiliation: Department of Chemistry, Purdue University, West Lafayette, IN 47907, USA.
authors.forename: Megan A
authors.initials: MA
authors.lastname: Macnaughtan
authors.forename: Aaron P
authors.initials: AP
authors.lastname: Smith
authors.forename: Peter B
authors.initials: PB
authors.lastname: Goldsbrough
authors.forename: Robert E
authors.initials: RE
authors.lastname: Santini
authors.forename: Daniel
authors.initials: D
authors.lastname: Raftery
mesh_terms: D005978:Glutathione / Q000032:analysis / Q000737:chemistry; D005982:Glutathione Transferase / Q000032:analysis / Q000737:chemistry; D008024:Ligands; D019906:Nuclear Magnetic Resonance, Biomolecular / Q000295:instrumentation* / Q000379:methods; D011485:Protein Binding; D012694:Serine / Q000032:analysis / Q000737:chemistry; D012815:Signal Processing, Computer-Assisted / Q000295:instrumentation
chemical_list: D008024:Ligands; D012694:Serine; D005982:Glutathione Transferase; D005978:Glutathione