| abstract |
The present inventions include methods and compositions for detecting the presence of ions and measuring the level or concentration of ions in a sample by nuclear magnetic resonance (NMR) using magnetic particles. In particular, the inventions include the preparation and use of magnetic particles having synthetic ion chelators covalently bound to their surfaces. In the presence of target ions, the surface-modified magnetic particles form clusters, which can be monitored by NMR relaxation measurements. The relaxation times can then be used to detect specific ions and determine their concentration. The described methods, compositions, and devices are useful for a variety of applications including biomedical applications in diagnostics and imaging. |