Most currently available vaccines, especially live and mRNA-based COVID-19 vaccines, are temperature sensi-
tive and require stringent cold-chain maintenance, entailing their storage and distribution at recommended tem-
peratures from production to administration. This necessity imposes the most prohibitive barrier to global im-
munization programs, particularly in developing countries, accounting for up to 80% of the cost delivery. Thus,
there is a critical need for a technology to provide cost-effective and long-term ambient temperature storage for
viral samples without requiring cold chain or complicated sample recovery protocols.
This proposal aims to develop an organic-ion platform for long-term storage of viruses at ambient tem-
perature to potentially reduce costs in the face of growing needs for new vaccines and avoid labor-intensive
maintenance associated with current biobanking technology. Ionic liquids (ILs) ¿ organic salts comprised entirely
of ions ¿ offer a well-suited platform on which the properties can be altered by the selection of ions, enabling the
tunable design of solvents/media for virus stabilization. We hypothesize that the solutions of proposed ILs with
ca. 20 wt% water may prevent hydrolytic and enzymatic degradation of viral genomes and protein capsids,
providing a reliable approach to preserve viruses. We will use a bacteriophage from the myovirus family as an
example of a naked protein particle and dengue virus as an example of a lipid-enveloped particle. First, we will
develop a thoughtfully conceived library of novel ILs through systematic variations of heterocyclic cations and
kosmotropic anions, and judicious incorporation of two functionalities (NH3+ and SO2F) into the IL structures.
Structural variability will be achieved by pairing new genre of biocompatible cations and anions. Second, we will
examine their effectiveness for stabilizing viruses by evaluating their structural integrity, thermostability, and
shelf-life from six months and four year. We will monitor changes in viral secondary structure, thermal denatur-
ation, and particle morphology. Last, we will study their empirical structure-activity relationships to gain compre-
hensive understanding of binding characteristics and molecular mechanisms of interactions between the viral
particles and the targeted aqueous ionic solvents via simulation, crystallographic, and spectroscopic methods.
This project will provide a viable solution for ambient temperature preservation of viruses for extended
periods (potentially for decades) by developing the virus¿IL¿water matrices that are stable towards hydrolytic
and enzymatic degradation. Another important feature of the proposed approach is that these nucleic acid-ILs
solutions can be directly amplified by PCR without being subjected to prior extraction, purification or quantifica-
tion. This approach has the merit of simplicity, which makes the process of ambient temperature storage and
distribution profoundly efficient, increases the stability of biosamples for prolonged time, reduces operational
costs and carbon footprint, and improves logistics for viruses and virus-based technologies.