New Pucks for Cryo-EM Grid Boxes to Simplify Sample Storage and Shipping

Cryo-EM sample preparation

One of the challenges in cryo-EM sample preparation is storing and shipping samples—especially for labs and facilities collecting data on a large number of samples. With this in mind, and the increasing popularity of cryo-EM, organizations are adopting longstanding sample storage solutions adapted from the x-ray crystallography community to enhance the storage, tracking, and shipment of cryo-EM grid boxes.

Cryo-EM grid boxes

During cryo-EM sample preparation, researchers apply samples to grids which are then vitrified by quickly plunging them into liquid ethane. To avoid destroying the samples, they must ensure these grids remain at cryogenic temperatures for all subsequent steps in the workflow including clipping, imaging, and storage.

To store cryo-EM samples, researchers commonly place the individual vitrified grids in cryo-EM grid boxes. They then place these boxes in labeled plastic conical tubes, which are attached to strings and submerged in liquid nitrogen—well-known as the “tube on a string method.”

While this setup works for labs that process a limited number of samples, many handle high volumes of cryo-EM samples, making tracking and labeling these samples a huge challenge. Moreover, it can be difficult to avoid damaging samples due to improper or excessive handling—especially as more facilities ship samples to outside labs for remote data collection.

It also is common for samples to get lost or damaged due to the tube cracking or string breaking.

Simplifying cryo-EM sample preparation

To address these issues, Thermo Fisher is excited to offer three different MiTeGen cryo-EM starter kits as an optional add-on for customers who purchase a cryo-electron microscope. The goal is to enable labs to source all cryo-EM equipment and workflow accessories in a single order, while giving them everything they need to get started with their cryo-EM research, such as holey-foil grids, cryogenic grid boxes, tweezers, Dewars and more.

Watch an on-demand Ask the Experts webinar with MiTeGen from November 2022 about tools and technologies for getting optimal results from highly challenging proteins >>

“When setting up a cryo-EM lab, getting the right tools and equipment for sample preparation and storage is a critical step.” said Benjamin Apker, Chief Executive Officer at MiTeGen. “Now, by simply adding a MiTeGen cryo-EM starter kit to their cryo-electron microscope order, research labs can confidently know they’ll have the leading technologies necessary to get started upon installation.”

MiTeGen capitalized on the storage practices used for X-ray crystallography by developing cryo-EM grid storage pucks that easily store and organize a large number of cryo-EM grid boxes. The pucks are engraved with unique identifiers and can be tagged via RFID for easy digital sample tracking. This simplifies the process of identifying and retrieving samples—especially for facilities that manage a large number of cryo-EM samples from different users. It also makes it easier to ship cryo-EM samples while reducing the chances that samples will be damaged or lost in transit. For example, if researchers internally screen grids on a Glacios Cryo-TEM and then ship the grids to an outside facility to collect data using a Krios Cryo-TEM, they can easily do so without damaging their samples. At the same time, external labs that receive these samples can better avoid the financial and legal ramifications of losing, damaging, or misidentifying them.

Learn more about MiTeGen cryo-EM starter kits >>

This blog was written in collaboration between Benjamin Apker, Chief Executive Officer at MiTeGen, and Edward Pryor, Director of Product Management at Thermo Fisher Scientific.