The system is comprised of two parts, canisters 100 and a docking station 200. The canisters are configured to hold at least one sample container 50 to which a RFID tag has been attached. The canisters also comprise a connector 102 that is configured to electrically couple to one of many ports 202 on a docking assembly that is mountable on the side of the cryogenic fluid vessel 12. The walls of the canisters may, radially outwards, be formed of a magnetic amplification layer, aerial layer and a magnetic shielding layer. The aerial (110, Fig. 2C) may be a circularly looped aerial situated at the base of the canister. The aerial may be connected to the RFID tag interrogator in the docking station via an electrical connection internal (108a, Fig. 2B) to the elongate rigid handle (108, Fig. 2A) of the canister. When connected to the docking assembly each canister can wirelessly interrogate the RFID tags of the containers held within the canister. The docking assembly may have an internal power source； be mounted around the neck of the cryogenic vessel； form an electrical connection with the lid of the vessel； have LED indicators； or be wirelessly connected to a server. The docking assembly also may have one or more RFID tag interrogators and may be operable to interrogate the contents of each canister in turn.
