藉由脈衝式磁場梯度核磁共振光譜法,吾人測得五種合成胜肽的擴散係數。由所測得之擴散係數推知,在298K的水溶液中這些胜肽是以單體形態存在,擴散常數值的差異主要是源自於分子大小的差別。而CD4片段及其雙苯基衍生物的擴散常數值之間的差異則反映出二者在分子構形間的不同。本文亦對脈衝式磁場梯度核磁共振光譜法的原理及沿革作一簡要的回顧。
Pulsed-field gradient (PFG) NMR spectroscopy has been used to measure the diffusion coefficients (Ds) for five synthetic peptides. The Ds values suggest these peptides are monomeric in aqueous solution at 298 K with the difference between Ds values arising primarily from the difference in molecule size. On the other hand, the difference between Ds values of a CD4 segment and its dibenzylated analog may reflect the difference in their molecular conformation.