NMR spectroscopy is an essential component of chemistry and biochemistry; it’s needed to characterize molecular structures at the atomic level and to determine the phase changes, conformational and configurational alterations, solubility, and diffusion potential of select compounds. Two kinds of NMR exist: solid-state, which aims to characterize solids and semi-solids, and solution NMR, which focuses on compounds dissolved in solution.
In the latest episode of LabTalks, we discussed new advancements in NMR spectroscopy and best practices for managing an NMR facility. To get a better understanding of NMR’s role in today’s research landscape, we invited Dr. Johanna Becker-Baldus, who runs the Solid-state NMR/DNP facility at the BMRZ (Center for biomolecular NMR) at the Goethe University Frankfurt, Dr. Konstantin Luzyanin from the University of Liverpool, and NMR facility manager at the Vrije Universiteit Amsterdam.
New NMR Technologies
When it comes to new NMR technology, probes are where one is sure to look first. Bruker, one of the leading manufacturers of NMR spectroscopy machines, has recently developed CryoProbe Prodigy, a series of nitrogen-cooled cryoprobes that enhance sensitivity. These probes are based on the same principles as helium-cooled probes but are used at the temperature range of liquid nitrogen. Dr. Luzyanin noted that these are easier to run and far more accessible, so they can be given to both undergraduate and graduate students to use.
Automatic probes represent another new addition to the NMR armory. Though most solution probes are automatic, they are now available for solid-state NMR, which has helped mitigate the need for manual instrument use. Bruker’s iProbe CPMAS represents one reliable solution, but other companies are getting in on automation solid-state probes, like JEOL.
Optimizing laboratory operations
Experience and needs are two of the factors that appear to heavily weigh on the organization of most NMR facilities. Like all research centers, students need to be trained on using new equipment, and considering the cost and complexity of running NMR, trust needs to be gained from those running the show. For Dr. Luzyanin, whose facility is shared by the entire university, they use only a select few machines specialized for manual use only, such as high-pressure NMR for the gas phase and some solid-state NMR instruments. Access to all NMR machines at the facility is organized using the Clustermarket booking system, the use of which is driven not by COVID, but by having a significantly large number of users. Similarly, NMR Facility Manager at the VU Amsterdam facility also uses the Clustermarket system, with a twist: they first gauge the expertise of the users, then partition them to only certain machines based on their experience level with NMR. For smaller facilities, like the one Dr. Becker-Baldus runs, machine time can be manually allotted for each user, although we still recommend having a booking system to ensure fewer human errors.
Training is also critical for a functional NMR facility, since everyone, from undergraduates to post-docs, require as much training with manual settings as possible, so they can learn to optimize their experiments and troubleshoot as well. During the meeting, Dr. Becker-Baldus reiterated that training is important to ensure personnel develop habits for acknowledging, reading, and utilizing specific protocols that are affixed to machines. Communication is also important for thinking outside the box, says NMR Facility Manager at the VU Amsterdam, who promotes the use of more elaborate protocols from colleagues outside of his usual research circle to show the expanded possibilities of NMR to his students.
Pros and cons of service contracts
Service contracts are an invaluable asset in research, as they allow scientists to ensure their complex equipment remains functional and running smoothly. However, when it comes to NMR, it appears as if many scientists rely on their own expertise to troubleshoot problems, mainly due to the expensive costs associated with these contracts. Both Dr. Luzyanin and Dr. Becker-Baldus rely primarily on in-house technicians and colleagues who are knowledgeable about NMR hardware. It seems that manufacturer support has been reduced in recent years, so depending on in-house personnel to diagnose problems beforehand and understand what parts to order is a primary solution to lowering costs. Our guests reiterated that repairs are usually made by ad-hoc service people and that an unfortunate amount of downtime is expected in their facilities when problems arise. The point that all our guests stressed was the importance of having a network to help solve problems when they arise, so that downtime is minimized and costs are kept low, especially considering tight research budgets.
One major focus of service contracts is freeing up time from performing maintenance so that scientists can focus on research, a point that Dr. Luzyanin reflected on. The size of the lab also plays a role in how useful they can be; in larger facilities, when a machine goes down, it’s not as noticeable, whereas the same machine malfunctioning in a small facility can reduce everyone’s work time to zero. Managing service contracts also plays a role, as it can be troublesome to manually sort through every contract; to this end, Clustermarket software has a feature that can reduce the time needed to organize and renew contracts. While service contracts may hasten general maintenance, it’s still important for users to understand how to troubleshoot special applications.
For probes, a specialized technician may be required for repairs anyway, according to Dr. Luzyanin: “There is one taboo…I never touch the probes. Cryoprobes are absolutely out of the question.” One of the companies that make probes, Bruker, also doesn’t publish the composition of their probes, so hiring independent technicians may risk damaging the probes via mishandling.
The lifespan of a probe
When asked how they manage probes to maximize their lifespan, our guests courteously suggested several useful (and critical) tips:
- Having more instruments is advantageous, as they can be used at a lower capacity. For instance, instead of having three instruments running at 100%, four instruments can be run at 75%.
- Make sure personnel handle tubes with gloves, avoid writing with a marker, prepare samples carefully, and clean surfaces accordingly.
- Restrict the type of consumables, such as tubes and cups, to only those specifically manufactured for use with NMR.
- Encourage automated measurement and restrict personnel from performing manual measurements to those who are sufficiently trained.
- Train personnel to recognize problems when they occur, such as when rotors are not spinning properly. It helps to provide an atmosphere where “there is no stupid question,” so that students aren’t afraid to ask when something goes wrong.
All scientists face a conundrum: while science is necessary to ameliorate the world’s problems, it may also contribute to them by producing a vast amount of plastic pollution.1 Therefore, we asked our guests what kind of solutions they were taking to lessen their facilities’ load on the environment.
Re-using tubes seemed to be the flavor of the day, as many students tend to unnecessarily throw out tubes when they’re done with them. NMR Facility Manager at the VU Amsterdam always asks students to check the tubes before each run and also tries to save solvent, where possible. Dr. Baldus-Becker usually tries to limit the number of caps and rotors used in each experiment; she even hides caps to make students think there are fewer than there really are so that students try to understand and utilize a limited amount of supplies.
Cryogens were also one of the main components that needed to be saved. Several systems exist, including those from Bruker, that allow for the recovery of nearly all boiled-off helium from the instrument, which is especially useful due to the rarity and high costs of the gas. Though the initial investment is relatively large for these systems, they ultimately pay for themselves in the long run by reducing the costs of re-obtaining cryogens and ensuring gas is available when needed. This is especially true for larger facilities with many machines that require relatively high volumes of cryogen. It’s also worth looking at how the system is set up, as that may change how much gas is recovered; in some cases, up to 90% of gas can be collected, though more often only around 50% is actually recovered.
If you are interested in hearing the full panel discussion, you can listen to it here. Check out our upcoming events for some more exciting panel discussions on topics like flow cytometry, microscopy, genomics, and more!