Each year millions of biological samples are processed, distributed, and stored worldwide. Currently samples such as DNA, RNA, proteins, bacteria, viruses, tissues, and other biological molecules are stored cold to prevent or reduce the rate of degradation. Even for small labs maintaining these cold environments requires multiple expensive refrigeration and freezer units, all of which greedily consume energy and limited laboratory budgets.
Current methods of sample transport are also problematic—as shipping frozen samples on dry ice is expensive, with shipments costing hundreds of dollars due to bulky containers and expedited delivery costs. Unfortunately even under carefully monitored cold storage environments, repeated freeze-thaw cycles and fluctuating temperatures only serve to promote degradation and compromise results.
All too often we are reminded that the power requirements necessary for a constant cold chain can be difficult to maintain through rolling blackouts, natural or man-made disasters, and the simple fact that only a small portion of the world can consistently supply power 24/7.
Power outages can lead to extensive and even insurmountable sample loss for individual labs, or even entire institutions, bringing into sharp focus the precarious nature of archived biological specimens. If a back-up freezer system is not available, precious samples are impossible to replace. The costs in economic terms are tangible, if not downright painful, to researchers who could use these resources more productively elsewhere.
Despite all the precautions taken to keep samples cold, preservation is still not perfect. The average DNA sample, one of Nature’s hardiest molecules, lasts for about a decade—not long enough if the sample is needed for future reference, as is the case for forensic samples.
Far more problematic are RNA samples, which are difficult to work with given their highly labile nature and tendency to degrade even under carefully controlled RNase-free conditions and cold storage. Even a short period of slightly elevated temperatures can compromise RNA integrity and detrimentally affect performance in downstream assays.
Interest in RNA is on the upswing due to its utility as a gene silencer and potential target for therapeutic drugs. A tremendous amount of research has also been devoted to its role in gene expression studies. Despite all of this, RNA remains decidedly scientist unfriendly. Once RNA is thawed, a certain anxiety overcomes the scientist to make sure everything is done quickly before it degrades. Current methodologies are limited to storing RNA, either purified or in tissue, in cold environments; until recently there were no products that stabilized RNA at room temperature.