Operators have to comply with government mandates forcing storage facilities to maintain accurate data of samples precise location, detailed description and handling procedures.
Historically, samples were identified by handwritten or printed labels and, more recently, barcoding. When material samples are stored at extremely low temperatures, vials are subject to intense frosting, making traditional identification difficult to read and document. It is vitally important to protect each sample from being damaged by a rise in temperature during the inventory process. Additionally, labels can become dislodged or illegible, further complicating identification. This process is damaging. Identifying and finding a particular vial or straw is time-consuming, and grave mistakes can occur.
As storage facilities expand, there are calls for tighter regulation and control. Auditing each sample is cumbersome and requires two highly qualified staff members working under strict health and safety timelines. Sample racks hold approximately 100 vials or straws, with each freezer or Dewar containing many hundreds of these racks. Every single straw or vial must be manually identified by reading each individual label. This process is not always accurate and statistically incurs a 9% error rate. These errors can result in legal damages and are frequently reported in the press.
Radio Frequency Identification (RFID) is now commonly used at ambient temperatures and above in many industrial and consumer applications. The focus of many new developments today is to survive high temperatures > 200°C (392°F) for industrial paint-shop processes and other applications.
On the other end, there are medical applications with the need to conserve live samples at freezing temperatures matching the boiling point for liquid nitrogen of -196°C (-321°F). Live biological samples need to be kept below -135°C (-211°F) to avoid degradation.
Uncontrolled temperature increases during inventory or retrieval of vials and straws is the biggest threat to destroying viable samples. Until now, RFID solutions did not address these types of harsh environments, as these low temperatures are typically outside the specification of such products.
Solution
Using a highly durable RFID tag designed for harsh environments with acceptable frequencies, Cryogatt Systems Ltd. worked with HID to develop an RFID tagging system to quickly and accurately identify and deliver a detailed audit of stem cell vials, fertility straw samples, and other material cryogenically stored in laboratories, bio-banks and fertility clinics.
This is achieved using HID’s RFID HF tags and specially designed Cryogatt readers. Tags are attached to samples cryogenically stored and to trays already positioned in deeply frozen storage. Each tag remains passive (inactive) in storage.
When in proximity to an RFID reader, the tags are wirelessly identified and encoded. As the vial sample is tagged, each sample is logged and its position recorded. The solution is simple, easily integrates with a facility’s existing IT system, and delivers accurate and timely records of all stored samples.
Results
Through extensive research, testing and deployments, HID and Cryogatt have partnered to produce viable tags used in extremely low temperatures for vial storage at fertility clinics or other storage facilities.
The ruggedness of HID RFID tags, with patented Direct Bonding Technology, survives the harshness of cryogenic storage at -196°C (-321°F). This is with over two million hours mean time between failures (MTBF), resulting in not a single failure being recorded by the National Institute of Biological Standards and Control (NIBSC) in the past two years.
Other suppliers’ RFID tags and chips were tested with mixed or negative results. For example, the unqualified tags only read at room temperature, lacked the required memory, or performed inconsistently.
Tiny Glass and Piccolino tags utilizing the HID HF Vigo™ Direct Bonding technology are embedded into cryogenic storage vessels. This patented technology allows the creation of extremely compact and robust transponders with high memory and security features.
Optimizing Cryogenic Work Processes
NIBSC is a global leader in the characterization, standardization and control of biological medicines.
NIBSC plays a major role in assuring the quality of biological medicine worldwide through the provision of materials, testing products and research. Expert scientists also provide advice on a routine basis and in response to worldwide emergencies.
NIBSC is the world’s major producer and distributor of WHO international standards and reference materials, supplying over 95% of biological international standards. The organization has approximately 200,000 vials of biological materials frozen in liquid nitrogen vapor (between -140°C and -190°C), using an antiquated process to track and manage long-term storage needs.
Stock-taking exercises indicated a historic annual error rate of up to 1%. The older vials date back 50 years, resulting in a higher location error rate. Without periodic, difficult inventory location exercises, accurately locating the older vials might be challenging.
Liquid nitrogen storage space is at a premium. Efficiency of storage is paramount to maximize space, but to avoid the dangers of mixing the locations of different cell banks, many storage spaces go unfilled. While the vigilance of staff over recent years has maintained a high level of storage location accuracy, more robust solutions were needed to guarantee accuracy and maximize efficiency.
NIBSC implemented the new Cryogatt RFID solution, and several hundred vials are now tagged with rugged RFID tags from HID across three liquid nitrogen freezers. Deploying advanced RFID technology, NIBSC is now able to accurately track, streamline inventory and simplify the management process of long-term vials.
The solution delivers precise data on available storage space down to the vessel, optimizing limited storage space. Getting in and out of storage freezers as quickly as possible is critical, as exposure of vials above the transition temperature of -135°C increases the risk of damaging the cells. On average, it is now two to five times faster to search and retrieve samples, reducing the risk of damage.
Additionally, access to detailed and accurate information significantly enhances quality system audit demands.
“The Division of Cell Biology at NIBSC has adopted the Cryogatt system of software and RFID readers to track cryo-tubes used in the production of cell banks. Having gained 24 months of experience with reliable reading at -190°C, the system is now being brought into routine use,” said Dr. Ross Hawkins, Principal Scientist, Division of Advanced Therapies, NIBSC.
As vials of cells at NIBSC are stored for decades, it is essential that any changes to their storage process remain effective long-term. A three-year trial of the Cryogatt technology is underway, with two years completed. The solution has experienced zero RFID tag failures so far and is on track for full deployment across NIBSC’s routine cell banking operations.
Bristol Royal Infirmary (BRI) Implementation
Bristol Royal Infirmary (BRI) is a teaching hospital in the UK with a research department storing short-term (24 hours) and long-term (five years) vials of biological samples. Currently, the management and coordination of research samples is complicated and inefficient using spreadsheets. BRI is looking to streamline sample management and expedite locating needed samples while ensuring compliance with the Medicines and Healthcare Products Regulatory Agency (MHRA) standards.
Implementing the advanced RFID solution by HID and Cryogatt has helped laboratory staff easily locate sample vials and retrieve information quickly and accurately. Samples are stored at -80°C across five freezers. Quite often, the exact location of a particular probe is unknown, making retrieval a time-consuming and costly manual process.
With the Cryogatt system, pick lists are simple to create, enabling an accurate pull of necessary samples.
“Traceability is accurate to satisfy regulatory standards and saves hours of searching,” said Kirsty Stevenson, Manager Cold Storage, Pathology Department, Bristol Royal Infirmary.
Additionally, the lab has been able to optimize storage space. Previously, up to 100 trays of usable storage went unnoticed because it was unclear where or how much space was left for new probes.
The research department is now running more efficiently using the solution. The plan is to primarily utilize the Cryogatt system for long-term (five-year) studies to maximize benefits.
Advancing the Future With Innovative Identification
Worldwide regulations are tightening the audit requirements for how laboratories manage biological sample storage. Clinics are increasingly concerned about the risks of human error and the legal ramifications of improper sample identification.
Applying RFID technology and automation solutions is gaining recognition in cryogenic storage and management. Key benefits include:
- Improves accuracy–Provides a secure source to quickly locate and identify vial samples
- Optimizes storage space–Increases visibility of usable storage and optimizes dewar utilization
- Ensures a precise audit trail–Complies with regulatory standards, making it easier to pass scheduled and drive-by audits
- Keeps samples safe–Reduces the risk of damaging viable cells or other bio samples by preventing accidental temperature increases above -135°C (-211°F) during slow inventory or retrieval processes. (Live samples must remain below this temperature at all times to stay properly preserved.)
- Saves time and costs–Enables bulk reading of storage trays at liquid nitrogen vapor-phase temperatures, allowing laboratories to locate each probe in seconds—far more efficient than manually recording frosted probes via barcode scanning or visual inspection
Deploying a solution capable of surviving a harsh and highly regulated cryogenic storage environment is critical to the success of laboratories, hospitals, fertility clinics and healthcare agencies worldwide.
“It ensures fast and efficient traceability and provides comfort that the data is accurate for that next compliance audit,” said Geoff Morris, Engineering Director, Cryogatt Systems LTD.
