Optimization of random time domain sampling in multidimensional NMR

The detailed description of rules for generation of different random sampling schemes is shown and discussed with regard to Multidimensional Fourier Transform (MFT). The influence of different constrained random sampling schedules on FT of constant signal, i.e., Point Spread Function (PSF), is analyzed considering artifacts level and distribution. We found that Poisson disk sampling schedule, which provides a large low-artifact area in the signal vicinity, is the method of choice in the case of nonlinear sampling of time domain in NMR experiments. We have verified the new sampling schemes by application to the 3D HNCACB and 15N-edited NOESY-HSQC spectra acquired for 13C,15N labeled ubiquitin sample.