Fast 0.7mm MAS - ultra-high speed 111kHz MAS probe

111 KHz probe for ultra-fast magic angle spinning

New insights from NMR analysis of biological solids and materials

Fastest available MAS frequency
Stable regulation
Unique possibilities in both biological solid state NMR and material science solid state NMR
Available for standard- and wide bore
Tools provided for easy filling and handling of the small diameter rotor and caps
High sensitivity despite small sample volume by high mass sensitivity and high RF fields strength

Bruker developed the 111 kHz MAS probe for ultra-fast magic angle spinning to provide a new tool for spectroscopists in solid-state NMR who need to improve their analytical capabilities with challenging samples. With a sample volume of 0.5µl and unsurpassed sensitivity, this probe is the perfect tool for studying structure and dynamics of biological samples as well as materials.

This new probe provides researchers with greater flexibility in terms of sample volume and spinning requirements, depending on the sample of interest. A newly developed MAS control unit, the MAS III controller, ensures the most stable MAS regulation at low and very high rotation rates. The 111 kHz MAS probe is available for all Bruker standard and wide bore NMR systems and comes with various tools, including a microscope for filling and easy handling of the small diameter rotors and caps.

"The ultra-fast magic angle spinning capabilities of Bruker’s 111 KHz MAS probe allows for the direct and high resolution observation of proton resonances from complex biomolecules. We get double the resolution in protonated samples compared to 60 kHz spinning. As such it is a great new tool in our arsenal for the structure determination of proteins, a critical need for studying disease mechanisms."

- Prof. Lyndon Emsley, Ecole Normale Superieure de Lyon

The requirements of magic angle spinning at very high spinning rates (> 100 kHz) lead to miniaturization of air bearing systems and turbines. The basic principles of gas turbines and bearing systems need to be adapted to the sub-mm range of dimensions, requiring novel manufacturing techniques for rotors, turbine caps, drive systems, and air bearings with an outstanding precision. For the user of such systems, new challenges of sample preparation and rotor handling arise. Automatic and semi-automatic regulation of air flow for sub-mm MAS systems must be addressed.

To reach and maintain stable MAS frequencies above 100 KHz, not only modern regulation hardware (MAS 3) needs to be available, but also super sonic conditions in air bearings and air drive need to be understood and controlled propely. In figure 2 an example of this supersonic drive flow can be seen.

Fig1. CPMAS at 111 KHz

CP H-H matching conditions under ultra fast MAS. The theoretical expected ZQ and DQ transfers can nicely be seen in the experimental data.

Data courtesy of Guido Pintacuda, ENS Lyon.

Fig2. CPMAS at 111 KHz

¹H detected proton-carbon correlation spectra for different types of biological systems studied without the need of deuteration 1. The left side shows a Cα-Hα dipolar correlation of microcrystalline GB1, while the right picture shows the same correlation acquired on a sedimented icosahedral nucleocapsid.

Data courtesy of Guido Pintacuda, ENS Lyon.

Fig3. CPMAS at 111 KHz

^K1H detected proton-carbon correlation spectra for different types of biological systems studied without the need of deuteration 1. The left side shows a Cα-Hα dipolar correlation of microcrystalline GB1, while the right picture shows the same correlation acquired on a sedimented icosahedral nucleocapsid.

Data courtesy of Guido Pintacuda, ENS Lyon.

BL07 CPMAS and MAS 3 regulation unit

Regulation profile of an BL07 CPMAS and MAS 3 regulation unit. The standard regulation deviation over 17h was less than 4Hz

Protein structure investigation and battery material research

1H-15N (CP/back-CP) correlation experiment with sedimented SSB (13C-15N labelled single-stranded DNA binding protein from E coli) at a proton frequency of 1GHz and 111 kHz MAS. TD1= 200/ns = 8, sample volume 300 nl, experimental time ca. 30 min. Right: 1H MAS spectra od Na3Tb(DPA)3 at different MAS rates. Double adiabatic echo experiment utilizing frequency swept Pulses for refocusing. Proton frequency 500 MHz, recyle delay 10 ms, 8192 scans. Frequency swept pulse length 18μs for 111 kHz MAS and 33.33μs for 60 and 30 kHz MAS.

Right: 1H MAS spectra od Na3Tb(DPA)3 at different MAS rates