# Explorative Supercooling Technology for Prevention of Freeze Damages in Vaccines
###### Abstract
Current methods of preventing vaccine freezing include, but are not limited to, constant temperature monitoring, high precision refrigerators, the development of freeze-resistant vaccines, and the use of phase change material (PCM) packs. The WHO has also published an official guide on how to prevent vaccine freezing. Guidelines include correct placement of vaccines within storage units, using water packs instead of ice packs to pack vaccines, and recording temperatures twice every 24 h [6]. However, it has been found that the WHO's recommendations have often been ignored [5]. The costs of the said methods can be prohibitively high, and there is an apparent lack of a cost-effective solution. PCM packs, freeze-resistant vaccines, and more accurate refrigerators are all costly and admittedly nonefficient. While mRNA vaccines are not of similar composition to those of the aluminum adjuvant type, remarkably unprecedented research during the current pandemic has been conducted to enable their expedient development, manufacturing, and shipping. Such research in bioinformatics, particularly research on the topic of genetic sequencing, has provided avenues for the development of a new class of vaccines. mRNA vaccines, due to their direct targeting of a virus's genetic and molecular structures, may prove to be a boon for the future of modern medicine. However, perhaps due to the novelty of these vaccines, their storage requirements are not a well-discussed matter at all. Early batches for trials were kept at \(-70\)\({}^{\circ}\)C by default. Various recommendations for storage temperature were eventually put forth for various prototypes and specific mRNA profiles; they were usually ultracold temperatures. For much of the development and initial production of these vaccines, ultracold storage was a dire yet perpetually unsatisfied need. More concerningly, long-term storage of mRNA vaccines was never intensely studied; many studies only reported short-term (six months) stability in vaccines kept in refrigerated conditions [9; 10] While bioinformatics has already proved its advantages in medicine development, basic needs must be met--such as proper storage--so that research can be done in an efficient yet effective manner. Currently, fully-developed mRNA vaccines against SARS-CoV-2 are stored in particular and often fastidious ways per the guidelines of their respective manufacturers. Some currently available vaccines are stored at extremely low temperatures before mixing with their respective diluents. For example, the Pfizer-BioNTech vaccine is only stable for ten days in dry-ice-supported thermal shipping containers. After shipping, the vaccine can be stored at ultracold temperatures (\(-60\)\({}^{\circ}\)C to \(-90\)\({}^{\circ}\)C) but only for two weeks. After this period, the vaccine must be stored in refrigerator conditions (\(2\)\({}^{\circ}\)C to \(8\)\({}^{\circ}\)C) for a maximum of 31 days [11]. The Moderna vaccine is, indeed, stable at (\(-15\)\({}^{\circ}\)C to \(-50\)\({}^{\circ}\)C) until its expiration date, but unused vaccines last for up to 30 days in a refrigerator [12]. In any case, ultracold freezing is never recommended as a long-term storage method. Instead, refrigeration offers a longer storage term with no risk of reduced potency. Though not entirely attributed to temperature abuse or damage, SARS-CoV-2 vaccines are often thrown out by the tens of thousands due to breakage, storage and transportation problems, and expiration [13]. A cold storage option covering all three conditional needs (thermal shipping, ultracold storage, and refrigeration upon thawing) can significantly benefit the vaccination effort against COVID-19 by boosting efficiency and distribution simplicity. During the late 1980s, a reliable \"shake test\" method to detect vaccine freezing was developed. Empirical observations in the field found visible differences between frozen-then-thawed vaccines and never-frozen vaccines.