Linewidth-resolved 15N HSQC, a simple 3D method to measure 15N relaxation times from T1 and T2 linewidths

A three-dimensional approach for measuring 15N relaxation times is described. Instead of selecting particular values for the relaxation period, in the proposed method the relaxation period is incremented periodically in order to create a 3D spectrum. This additional frequency domain of the transformed spectrum contains the relaxation time information in the T1 and T2 linewidths, and thus the longitudinal and transverse 15N relaxation times can be measured without determination of 2D cross peak volumes/intensities and subsequent curve fitting procedures.