Why proper storage and sample handling often means success or failure in the lab
Quality sample management is a well-known challenge for life science investigators. As the pharmaceutical industry and forensics industry demand an ever-growing number of usable, well-maintained biospecimen collections, so increases the need for completely automated biobanks to store these samples properly.
The Cancer Genome Atlas (TCGA) program, which ended in 2009, experienced one of the most notable examples of genetic sample degradation associated with poor storage standards. This $50 million study suffered a major setback in the early phases when nearly 99% of the samples it received from various biobanks were substandard. This led to major reforms in quality standards for biobanking organizations, led by the Office of Biorepositories and Biospecimen Research (OBBR), which published its first sample storage guidelines in 2006.1
The thawing effect
Figure 1 – A large-capacity Hamilton BiOS system capable of storing 2 million samples at –80 °C.
Constantly freezing and thawing samples can adversely affect quality: A door held open on a manual freezer for even a short period can result in a significant temperature increase. Data gathered by Hamilton Storage Technologies (Franklin, MA) showed that the temperature of samples kept in 300 μL REMP™ tubes (Brooks Life Science Systems, Manchester, U.K.) with 40 μL Fisher 10× TBS pH 7.4 buffer (Thermo Fisher Scientific, Waltham, MA), when taken from –80°C storage to ambient conditions, increases by an average of up to 21.5 °C/min.
Freezer doors are sometimes held open for more than a minute, and this can occur countless times over the lifetime of a sample stored and retrieved manually. Accumulated temperature elevations above this level are believed to damage the integrity of many biospecimen types.2
Automation and –80 °C: The perfect marriage for sample stability
Figure 2 – Inside view of the BiOS system and robotic arm at work.
One result of the new OBBR guidelines was the emergence of automated biobanks. These systems are designed to minimize manual handling and keep internal temperatures constant by using robotic handling equipment to receive and retrieve samples.
Many biobanks store hundreds of thousands, if not millions, of samples for extended periods of time. The Netherlands Forensic Institute (NFI), for example, must maintain crime scene samples for up to 80 years. To achieve this level of storage stability, Hamilton designed the BiOS system, which is the only biobanking solution to keep samples in –80 °C environments throughout the entire storage and picking process (see Figures 1 and 2).
Audit trail as important as temperature stability
Thousands of precious research samples have been lost over the years after thawing due to system and human error. Having storage system software that provides a full audit trail for each sample is as important to sample quality as temperature controls.
Biobanking system software can record who handles the sample and for how long, and any temperature changes the sample may experience while in the system. In addition, these automated systems must have sophisticated backup capabilities in case of failures.
Do you know how your samples have been treated?
Given the high level of care required for adequate sample storage, it is not surprising that an increasing number of studies are inaccurate or greatly compromised by poor sample quality. Automated storage systems and integrated robotics help ensure sample integrity and speed progress in genetics analysis.
Facilities making upgrade choices need to consider the current security and safeguards of their sample procurement process. If sample quality is lost, so may be hundreds of thousands of dollars of precious study information.
- National Cancer Institute, The Cancer Genome Atlas; Program Overview History and Timeline; http://cancergenome.nih.gov/abouttcga/overview/history.
- Betsou, F.; Rimm, D.L. et al. What are the Biggest Challenges and Opportunities for Biorepositories in the Next Three to Five Years? Biopreservation and Biobanking 2010, 8(2); doi:10.1089/bio.2010.8210; http://www.apallograft.org/uploads/3/1/2/4/3124517/bioexpertspeak_june2010.pdf.
Martin Frey, Ph.D., is head of the Storage Technology Market Segment at Hamilton Bonaduz. Dr. Frey has been with Hamilton Company since 2009 and is currently the acting product manager for the BiOS automated sample storage system; www.hamiltoncompany.com.