Chemically cross-linked polyacrylonitrile. A DMSO compatible NMR alignment medium for measurement of residual dipolar couplings and residual chemical shift anisotropies.

Chemically cross-linked polyacrylontrile polymer gels, have been prepared as an alignment medium compatible with DMSO-d. These gels allow measurement of residual dipolar couplings (RDCs) and residual chemical shift anisotropies (RCSAs) with good accuracy as tested with brucine and α-santonin natural compounds. The gels can be reversibly compressed allowing easy measurement of RCSAs. They also present good physical homogeneity, clean HSQC spectra with little background H signals, and allow unambiguous referencing of C spectra for RCSA extraction.