Speeding up the measurement of one-bond scalar (1J) and residual dipolar couplings (1D) by using non-uniform sampling (NUS).

The accurate and precise measurement of one-bond scalar and residual dipolar coupling (RDC) constants is of prime importance to be able to use RDCs for structure determination. If coupling constants are to be extracted from the indirect dimension of HSQC spectra a significant saving of measurement time can be achieved by non-uniform sampling (NUS). Coupling constants can either be obtained with the same precision as in traditionally acquired spectra in a fraction of the measurement time or the precision can be significantly improved if the same amount of measurement time as for traditionally acquired spectra is invested. The application of NUS for the measurement of (1)J (scalar coupling constants) and (1)T (total couplings constants) from different kinds of ω(1)-coupled spectra (including also J-scaled ones) is examined in detail and the possible gains in time or resolution are discussed. When using the newly proposed compressed sensing (CS) algorithm for processing, the quality of the spectra is comparable to the traditionally sampled ones.