The Harvard Chan Freezer Core is designed to assist in the management and storage of samples for PI eligible investigators. This large capacity negative 80°C freezer has the ability to store 100,000 to 10 million samples, depending on labware size. The Harvard Chan Freezer Core is intended to be an alternative storage option to upright and chest negative 80°C freezers, conserving costs, energy, and space, while ensuring sample integrity, access, and tracking.

Terminology

A nest is a self-contained storage compartment, equivalent to a chest freezer. The freezer holds 10 nests, each kept at -80°C and containing 150 cassettes. A robot is able to open individual nests without disrupting the others.

A cassette is a set of shelves for the storage of racks. It is the equivalent of a freezer rack. The number of shelves per cassette can vary from 9 to 20. A robot can lower and raise these cassettes into and out of nests.

A rack is the equivalent of a freezer box and contains tubes. Each rack must be a standard SBS footprint and have a laser-etched 2D barcode. The freezer will scan each rack and any samples within the rack with 2D barcodes in order to track your samples throughout the storage and retrieval process.

Sample Integrity

All samples in the freezer can be picked by a robot without opening the door of the freezer and exposing the samples to ambient temperatures. The sample picker is kept at -80°C to ensure that the samples remain cold as they are moved through the -20°C environment surrounding the nests. The freezer door remains closed, ensuring temperature stability of your samples and mitigating moisture in the storage compartment.

The automated system provides two layers of refrigeration redundancy to protect your samples. Each nest within the freezer has a primary and secondary cooling unit and access to liquid nitrogen (LN2) to protect the samples in the event of multiple failures.

Sample Access and Tracking

The freezer is able to use 2D barcode reading to track and record every movement of your sample including the person responsible for introduction and retrieval of the samples. Automation increases picking speed and is able to work overnight and on weekends. Picks can be created and executed remotely and completed outside of normal work hours. If the picks are completed outside of a normal workday, they can be stored in a -80°C cache inside the freezer until they are retrieved.

Through the use of 2D barcodes, automated background defragmentation can allow users to maximize the available capacity of the freezer without losing track of samples.