Analysis of biofluids and chemical mixtures in non-deuterated solvents with1H diffusion-weighted PFG phase-sensitive double-quantum NMR spectroscopy

Multiple-Quantum NMR Studies on Molecular Mixtures

“…Dalvit et al [28] revisited this particular coherence order for the simplification of the spectra of mixtures. While DQ-1 H spectroscopy shares all the issues related to intensity dependence on the τ parameter, one of its main assets is that it provides a spectrum tantamount to COSY but without the nuisances linked to the presence of diagonal peaks.…”

“…In a first application of combined MQ and diffusometry to mixtures, Dalvit et al [28] incorporated diffusion-editing during the pumping period, to allow measurement of the diffusion coefficients using a 2Q correlation Figure 24 Comparison of 3Q-1Q correlation spectra recorded and processed with different US and NUS schemes. The sample was a mixture of aromatic compounds (phenol, o-terphenyl, dibenzyl, acetanilide, benzophenone, fluoranthene, naphthalene, anthracene, phenanthrene, triphenylene).…”

“…Thus, the relaxation term becomes a simple multiplicative factor, and a plot of Ln(I(τ 1 , τ 2 ) versus τ 3 1 + τ 3 2 À Á provides a linear decay allowing to determine D. This setup is perturbed, as all other NMR Figure 25 Pulse sequence for a diffusion-edited DQS as used in Ref. [28]. The gradients of variable intensity for encoding the diffusion decay are placed during the pumping period.…”

“…Reproduced from Ref. [28] with permission from John Wiley and Sons. Figure 26 Pulse field gradient decays of DQ signals of cross-peaks from the 2Q spectrum as a function of the increasing gradient strength.…”

“…An expanded region containing the spin systems of glucose and the residual H 2 O signal is shown. Reproduced from Ref [28]. with permissions from John Wiley and Sons.…”