Nuclear Magnetic Resonance of Biomolecules

摘要: Nuclear magnetic resonance (NMR) spectroscopy exploits a property of the nucleus known as nuclear spin, which exhibits angular momentum and such generates local field that can be influenced by larger static external field. In presence large magnet, spins align with field, slight excess opposed to That small flipped alignment in radiofrequency (RF) pulse appropriate frequency. Relaxation those back ground state results emission RF radiation whose frequency is an indication electron density molecule spin resides. Such information ultimately directly related molecular structure. NMR unique it used image whole human body at one extreme, determine three-dimensional (3D) structure biomolecule within other extreme. The principal advantages are that: (i) complete determined; (ii) technique spans all states matter (solid, liquid, gas); (iii) method nondestructive noninvasively, clinical setting. disadvantages very insensitive (typically samples below 50 µM difficult study, although recent advances nanoprobe cryprobe technology rapidly revising these numbers); liquids there weight limits around 50 kDa – new methods being developed may have significant impact on this; solids only limited structural obtained date.