HRMAS and CMP Probes
 
 

Discover the full potential of our CMP iProbe and HRMAS iProbe by scheduling a customer demonstration at one of our global locations. Our team of experienced Application specialists will guide you through NMR measurements on our cutting-edge equipment, showcasing all features in action. If you are unable to visit us in person, remote demos and sample submissions are available to ensure you have access to our innovative technology from anywhere in the world. Schedule your demo today and experience the power of Bruker NMR.

High Resolution Magic Angle Spinning (HRMAS) is an established technique for analyzing inhomogeneous and semi-solid samples. With standard solution-state NMR techniques, the spectra of such samples would suffer from broad and unresolved resonances. By spinning at the magic angle (54.7°), line broadening effects due to magnetic susceptibility differences and dipolar interactions within the sample are removed, enhancing spectral resolution, and enabling detailed analysis of the individual components within the sample. HRMAS is the ideal technique to investigate many important classes of samples, such as gels, emulsions, foodstuffs, insoluble polymers, or biological tissues.

Bruker's HRMAS probes are equipped with a gradient coil oriented along the magic angle and a deuterium lock channel. The gradient has been optimized for durability and makes a wide variety of NMR techniques accessible, including gradient enhanced solvent suppression and artefact-free homonuclear and heteronuclear 2D experiments. The tunable deuterium lock channel provides excellent frequency stability over long acquisition times.

Built upon the renowned iProbe platform, Bruker’s HRMAS NMR probes combine innovation, ease-of-use, and reliability. Bruker’s HRMAS iProbes feature integrated automatic tuning and matching, automatic magic angle adjustment, and are compatible with hardware for automatic sample changes. The HRMAS iProbe, shown in Figure 1, is available as a dual channel probe, where the high frequency channel is tunable to ¹H and ¹⁹F, and the second channel covers a wide frequency range from ³¹P to ¹⁵N. The robust RF design makes it possible to decouple for long times, both on the X and ¹H channel, allowing a high resolution in both dimensions even under heteronuclear decoupling.

Bruker’s HRMAS iProbes are available for standard bore (SB) magnets and are compatible with wide bore (WB) magnets. The probes are available for 4 mm rotors, capable of a maximum spinning speed of 15 kHz. Disposable rotor inserts are available for easy sample preparation and clean up.

Examples for typical application of HRMAS NMR are shown below.

In medical applications, HRMAS is often applied as a nondestructive and nonperturbing method to study cancer and other pathologies by analysing tissues, blood, or cells. Due to the exceptional resolution achieved with HRMAS NMR, serial measurements of important metabolites are possible without complex extraction and purification processes.

One major field of industrial applications of HRMAS NMR is the characterization of insoluble polymers swollen in a suitable solvent. Scientific questions typically address physiochemical phenomena, like adhesion, elasticity, or degradation, and their relation to local structures such as the degree of cross-linking or the presence of chain dynamics.

Gels, emulsions, and creams are common in the manufacturing of food, cosmetics and pharmaceuticals. They can be analysed by HRMAS spectroscopy in their original form in an easy and convenient manner, without prior sample treatment.

Bruker also offers a range of CMP (Comprehensive Multiphase) probes. CMP probes share many similarities with the HRMAS probes, boasting the same high-quality construction, gradients, a lock channel, and compatibility with 4 mm rotors spinning at 15 kHz. In addition to the capabilities of HRMAS probes, Bruker’s CMP probes have been optimized with respect to power handling and thus provide an extended array of experimental techniques, including cross polarization (CP) experiments, and high-power decoupling, enabling researchers to extract even more detailed information from their samples.

Application examples for NMR experiments which were performed with a CMP probe are shown below.