A device is provided for securing a tissue sample from biological material. The tissue sample is housed in bottom and top platens that are configured to promote fluid communication between the tissue sample and the exterior environment to permit transport or cryogenic fluid to contact the sample. Additionally, diskette assemblies may be provided within the platens that permit sub-samples to be separated without directly handling the tissue sample. The diskette assemblies may also be configured to promote fluid communication with the sub-sample housed therein.