Demonstration of the linear dependence of proton magnetization transfer on polymer concentration in aqueous gels at two different field strengths
✍ Scribed by Jean J. Tessier; Kimberlee Potter; T. Adrian Carpenter; Laurance D. Hall; Jenny A. Tyler
- Publisher
- John Wiley and Sons
- Year
- 1994
- Tongue
- English
- Weight
- 592 KB
- Volume
- 32
- Category
- Article
- ISSN
- 0749-1581
No coin nor oath required. For personal study only.
✦ Synopsis
Abstract
Saturation transfer experiments were performed at both 85 and 300 MHz to measure the magnetization transfer (MT) rate as a function of macromolecular concentration. For this purpose calcium alginate gels with an internal concentration gradient were manufactured from aqueous sodium alginate and calcium ions. Although aqueous sodium alginate did not exhibit any MT, the proton magnetization transfer rate in calcium alginate gels was found to depend linearly on the concentration of polysaccharide. Since the rate did not depend on the field strength, the dominant mechanism of MT in these systems is either chemical exchange or a highly efficient intermolecular cross‐relaxation process. The high sensitivity of MT to variation in polysaccharide concentration and mobility suggests that it is an excellent tool to monitor changes in the chemistry, mobility and concentration of slowly moving polymers in aqueous gels.