BioSolids CryoProbe

Increasing Sensitivity Without Sample Modification

While being extremely versatile, NMR has the inherent challenge of being insensitive. One strategy to improve the sensitivity which does not require sample modification is cryogenically cooling the RF coil and preamplifier electronics. The reduced level of thermal noise generated by the RF coil, network, and preamplifier lead to a boost in signal-to-noise on the order of 3 while keeping the sample in its original composition and with its natural line width. This progress report shows results obtained with our first 600 MHz 3.2 mm HCN triple resonance CPMAS CryoProbe prototype.  

The probe is designed for standard bore magnets and compatible with the well proven CryoPlatform. Cryogenic cooling of the RF coil and preamplifier electronics yields a sensitivity gain of more than 3 compared to conventional probes. This gain is achieved with the sample staying at room temperature.

The probe reaches MAS rates of 20 kHz with 3.2 mm rotors and the MAS3 unit. The CPMAS CryoProbe can be lowered while in the cold state with a new probe lift allowing for easy and safe rotor exchange. Automatic tuning and matching adds to the probe’s comfortable and safe operation.

Technical Details

•¹³C and ¹⁵N –optimized triple resonance NMR probe

•Enhancement ¹³C and ¹⁵N sensitivities by a factor of >3

•One order of magnitude faster data acquisition and significantly increased productivity

•Simultaneous irradiation on ¹³C and ¹⁵N under strong proton decoupling

•Ideally suited for research on biosolids with low level of labeling and small molecules in natural abundance

•Automatic tuning, matching and magic angle adjustment and lift-assisted sample exchange

•Sample temperature range: -20 C to +60 C

•MAS rates up to 20 kHz with specially designed 3.2 mm rotors

•Standard bore design, compatible with SB and WB magnets.


The BioSolids CryoProbe allows to study challenging biological systems under physiological temperatures and without altering  their sample composition.

This feature is extremely important in structural biology, as the integrity and temperature of the protein surrounding, are often crucial to maintain the biological function.

Diluted samples, such as labelled proteins in their native environment or small molecules in large assemblies, and samples in natural abundance or with low level of labelling, greatly benefit from the significant boost in sensitivity of this innovative probe.

In the pharmacological context, this probe allows to expand the NMR toolbox. 2D ¹³C¹³C correlation experiments can be routinely used for advanced characterization of active pharmaceutical ingredients in natural abundance. Other fields of applications include drug polymorphism and drug-delivery systems

Faster Data Acquisition

Amyloid fibrils and Prions

~ 96.7 mg (u- ¹³C, ¹⁵N) HET-s (218-289) prion domain, courtesy of prof. A.Loquet, CNRS, Bordeaux, France.

Thanks to the enhanced sensitivity the spectra are recorded one order of magnitude faster and it’s possible to record the spectra with just a single scan and with an amazing signal-to-noise and resolution.

Faster Data Acquisition
Amyloid fibrils and Prions

~ 96.7 mg (u- ¹³C, ¹⁵N) HET-s (218-289) prion domain, courtesy of prof. A.Loquet, CNRS Bordeaux, France.

Thanks to the enhanced sensitivity the spectra are recorded one order of magnitude faster and it’s possible to record the spectra with just a single scan and with an amazing signal-to-noise and resolution.

This results into a large time saving for the setup and acquisition of multidimensional experiments.

Gain One Dimension
Amyloid fibrils and Prions

~ 96.7 mg (u- 13C, 15N) HET-s (218-289) prion domain, courtesy of prof. A.Loquet, CNRS Bordeaux, France.

With the sensitivity provided by the BioSoldis CryoProbe the number of scans can be drastically reduced. As a consequence, the multidimensional experiments become faster. It is then possible to perform a 3D experiment in the same time normally required to run a 2D experiment. Also 4D experiments, routinely not performed because of too long acquisition time, become accessible, requiring less than a week of experimental time.

Explore Low Sensitivity Samples
Large biological assemblies

~ 7.5 mg of U – ¹³C, ¹⁵N – labeled Kif5b, a 349-residue protein, complexed with microtubules. Total sample amount ~ 80 mg, courtesy of prof. T.Pollenova, U.Delaware, USA.

Thanks to the sensitivity enhancement more challenging samples, more complex or less labeled, become the focus of the researcher.

We have recorded 3D NCACX and NCOCX experiments have been recorded on sample constituted of  a labelled protein of about 350 residues in a complex with an unlabelled protein (total The total amount of isotopically labeled material is ~9 %).
These experiments, which lasted for ~5 and 6 day respectively,  demonstrate the stability of the probe over several days of accumulation under multiple steps of simultaneous irradiation on all RF channels.

Biological Samples in their Native Environment
Bacteria cell envelope of mycobacteria

~ 40 mg ¹³C, ¹⁵N-labeled cell wall, HEPES 50 mM pH 7.0, courtesy of prof. J.P.Simorre, U.Grenoble, France.

Thanks to the sensitivity enhancement, the researchers can look with solid state NMR directly into cells.

This probe is a game changer for unstable samples that tends to degrade fast over time. On these kind of samples is crucial to be able to collect all the data shortly after they production.

Natural Products at Natural Abundance  
Wood and Cellulose

Wood from Bordeaux wine threes, courtesy of prof. A.Loquet, CNRS Bordeaux, France.

Wood and other cellulose-rich samples typically present a mixture of amorphous and crystalline materials, and therefore a mixture of large and narrow signals. Distinguish between the different overlapping spectral components in a ¹D ¹³C experiment is often not easy. Being able to improve the resolution with a ²D CC correlation experiment is sometimes the only viable way to assign the spectral components. With the improved sensitivity of the BioSolids CryoProbe a refocused INADEQUATE become a routine tool.

Natural Products at Natural Abundance  
Native collagen inside bone matrix

Cortical femora bone of Goat (Capra hircus, 2-3 years old). N.Sinha, Centre of Biomedical Research, India.

Understanding the structural and functional behaviour of collagen in its true native state in healthy and diseased conditions is a milestone for the development of treatments for various bone degenerative diseases, tissue engineering, and bone implants. Natural abundance spectra of collagen typically suffer of low sensitivity and limited isotopic concentration.
Thanks to sensitivity enhancement of this probe, it is now possible to record high-resolution 2D ¹H-¹³C HETCOR experiments of collagen in natural isotopic abundance. The spectra, recorded at short and long contact times , shed light on short and long-range interactions  of collagen inside the bone matrix in its true native environments. With this probe, the researchers go one step further in the understanding of the structural stability and functional mechanism of collagen inside the bone matrix.

In-situ Characterization of Active Pharmaceutical Ingredients
Cyclodextrin-based metal-organic frameworks (CD-MOFs)

CDMOFs particles loaded with ~ 20 % Lansoprazole, courtesy of prof. C.Martineau-Corcos, CEMHTI UPR CNRS 3079, ILV UMR CNRS 8180, and IUF, France.

Drug-delivery matrixes are often porous materials which resemble sponges. Metal-organic frameworks (CD-MOFs) are good example, as they are materials with a huge empty volume. Drugs loaded into MOFs represent a case of diluted spin systems, in which the sensitivity lack represent a big issue for the in-situ characterization of the active ingredient.

It is worth to note that the cryoprobe technology is so far the only tool that allows probing the state of a low API content in these kind of samples. Other approaches, like fast MAS 1H NMR or DNP have been demonstrated to be not suitable or of limited use, because of lack of resolution and unstability of CD-MOFs in the solvents used for DNP sample preparation.

A) Vitamin B12 B) 2D 13C-13C INADEQUATE on natural abundance Vitamin B12. 80 increments of 1024 scans each, acquired within a total experimental time of 3 days and 9 hours. The spectrum was processed using covariance.

Advanced Characterization of API

Thanks to the superior sensitivity of the probe, advanced characterization of an API can be performed without resorting to isotopic labeling. This is illustrated with a CC double quantum correlation on vitamin B12 at natural abundance. The refocused INADEQUATE has notoriously low sensitivity, and it would have taken more than one month acquisition time on a RT probe.

Standard signal-to-noise comparison for 13C with glycine, illustrating the more than 3-fold enhancement factor compared to a traditional room temperature probe with the same amount of sample material. The spectrum shows that the magic angle is well set and that 1H high power decoupling is stable.

CP and Double-CP based Experiments

The CPMAS CryoProbe is developed for standard and advanced CP-based experiments in structural biology.

Combining the high sensitivity with NUS can be used to significantly improve the spectral resolution or reduce the experimental time. A) shows a CC correlation on uniformly labeled fMLF using traditional sampling (~4 h), B) shows the same experiment using 25% NUS sampling (~1 h).

Combining High Sensitivity with NUS

The high sensitivity of the new probe in combination with Non-Uniform Sampling techniques enables a dramatic reduction of experiment times. The CPMAS CryoProbe allows up to 10 times faster data acquisition for sensitivity limited samples.

Service and Support


Service & Life Cycle Support for Magnetic Resonance and Preclinical Imaging

Bruker’s commitment to provide customers with unparalleled help throughout the buying cycle, from initial inquiry to evaluation, installation, and the lifetime of the instrument is now characterized by the LabScape service concept.

LabScape Maintenance Agreements, On-Site On-Demand and Enhance Your Lab are designed to offer a new approach to maintenance and service for the modern laboratory


1.NPM1 exhibits structural and dynamic heterogeneity upon phase separation with the p14ARF tumor suppressor
Eric Gibbs, Barbara Perrone, Alia Hassan, Rainer Kümmerle, Richard Kriwacki.
Journal of Magnetic Resonance, 2020, 310, 10646

2.Sensitivity Boosts by the CPMAS CryoProbe for Challenging Biological Assemblies
Alia Hassan, Caitlin M.Quinn, Jochem Struppe, Ivan V.Sergeyev, Chunting Zhang, Changmiao Guo, Brent Runge, Theint Theint, Hanh H.Dao, Christopher P. Jaroniec, Mélanie Berbon, Alons Lends, Birgit Habenstein, Antoine Loquet, Rainer Kuemmerle, Barbara Perrone, Angela Gronenborn, Tatyana Polenova.
Journal of Magnetic Resonance, 2020, 311, 106680

3.Efficient incorporation and protection of lansoprazole in cyclodextrin metal-organic frameworks
Xue Li, Marianna Porcino, Charlotte Martineau Corcos, Tao Guo, Ting Xiong, Weifen Zhu, Gilles Patriarch, Christine Péchoux, Barbara Perrone, Alia Hassan, Rainer Kümmerle, Alexandre Michelet, Anne Zehnacker-Rentien, Jiwen Zhang Ruxandra Gref.
International Journal of Pharmaceutics, 2020, 585, 119442

4.Probing short and long-range interactions in native collagen inside the bone matrix by BioSolids CryoProbe
Nidhi Tiwari, Sebastian Wegner, Alia Hassan,  Navneet Dwivedi, RamaNand Rai, and Neeraj Sinha.

Accepted in Magnetic Resonance in Chemistry