Measurement of diffusion constants for nucleic acids by NMR

Pulsed field-gradient NMR experiments can be used to measure thediffusion constants of nucleic acids. The diffusion constants measured inthis way for double-helical DNAs of defined length agree well both withtheory and with measurements done using other techniques. When applied toRNAs, this experi- ment easily distinguishes duplex RNAs from RNA hairpinsand thus it can solve one of the perennial problems faced by RNAspectroscopists, i.e. assessing whether their samples are monomeric or not.