The 4D HN(CO)CAHA experiment has been designed to trace out sequential backbone connectivites in large proteins using a single experiment. The same connectivities and intraresidue connectivites can be also observed in a 4D HACANH experiment.

Implementation on AVANCE spectrometers equipped with a triple-resonance probehead is feasible. Improved versions using pulsed field gradients (PFGs) are also available and, therefore, in such cases gradient technology is required. The experiment is recorded on a ¹³C,¹⁵N-labeled protein in H₂O.

The 4D HN(CO)CAHA sequence was described in 92JMR443-98 and 92JMR444-100 .

A reduced-dimensionality 3D HNN(CO)[CAHA] ( 02JB41-24)

A related 4D HCA(CO)NH experiment which use the reverse transfer pathway has been also reported ( 92JACS2262 , 92JB631 , and 96JACS407 ).

The 4D HN(CO)CAHA experiment can be recorded in automation mode.