Determination of the Bound Water Fraction in Cells and Protein Solutions Using17O–Water Multiple-Quantum Filtered Relaxation Analysis

✍ Scribed by Evelyne Baguet; Bogdan E. Chapman; Allan M. Torres; Philip W. Kuchel

• Publisher: Elsevier Science
• Year: 1996
• Tongue: English
• Weight: 174 KB
• Volume: 111
• Category: Article
• ISSN: 1064-1866
• DOI: 10.1006/jmrb.1996.0053

✦ Synopsis

Multiple-quantum filtering NMR sequences were used to study

Studying water relaxation by 17 O NMR permits the selecthe multiexponential relaxation behavior of H 2 17 O in the presence tive analysis of the effect of reorientationally hindered water of macromolecules. By this means, the fraction and the correlation on the overall relaxation process; it has already been emtime of water in slow motion, or ''bound'' water, were determined, ployed to study protein hydration (4). In the latter work, it as well as the relaxation time of bulk water in the extreme-narwas assumed that because of the small fraction of bound rowing limit. Aqueous solutions of bovine serum albumin and inwater, its magnetization evolved almost monoexponentially tact human red blood cells were studied. The small fraction of and only two relaxation times, for longitudinal and transbound water of less than 1% appeared to correspond to ''strongly verse relaxation, were investigated. Thus, the weakly multibound'' water, whereas the behavior of bulk water was different exponential behavior of the water signal, due to the slow from pure water and was interpreted as being due to weak (or motion of the water when bound to macromolecules, was transient) interactions with macromolecules. The experiments and the data analysis appeared to be reproducible, which suggests that incompletely analyzed, and these experiments were required diverse samples might be studied this way and thus help define to be carried out at different magnetic field strengths and at the properties of water in these systems.