The process of cryopreservation involves heat transfer during cooling and rewarming, which plays a crucial role in determining the success of vitrification and viability. The improved cooling rate is enhanced mainly by i) high thermal conductivity mesh material (k ≥ 10 W/m/K) to achieve conduction-dominated behavior and ii) vertical plunging method to reduce the Leidenfrost effect achieving higher convective heat transfer rates, which enhances the heat release of the biosystem into LN2 (liquid nitrogen). This cryomesh enables the preservation of large-quantity biosystems with high throughput, consistency easy protocol, and high viability, which has the potential to be a standard tool for cryopreservation research due to its easy scalability with surface area. 

Climate change has dramatically impacted oceanic ecosystems and endangered many of the coral populations around the globe. One of the most effective methods to secure the biodiversity of coral is the cryopreservation of coral larvae to assist gene flow and rewild reefs. The conduction-dominated cryomesh approach for coral larvae cryopreservation with a high survival rate (85%) and scalability to larger numbers (> 200 per loading) using larger or multiple cryomesh. Compared to the previous approach of laser rewarming, the cryomesh method doubled the survival rate and only needed 0.2% of the operation time compared with laser rewarming. The cryomesh has been used for the biobanking of mushroom coral larvae in Hawaii by our collaborators from the Smithsonian Institute and the University of Hawaii, as well as by collaborators from Taronga Conservation Society Australia and the University of New South Wales in Australia for biobanking mushroom coral from Great Barrier Reef.

The fruit fly (Drosophila melanogaster) is a foundational genetic model organism for biological research, which has >160,000 unique genotypes held in individual research laboratories and stock centers worldwide with a growing number. Cryopreservation has the potential to decrease stock maintenance costs and reduce the risk of stock loss for long-term storage. I demonstrated that the conduction-dominated cryomesh approach can lower the required CPA concentration for Drosophila embryos while achieving high hatch rates (3.3 X higher than conventional cryomesh). This will be critical for expanding use to biosystems that are more susceptible to CPA toxicity. This work also collaborates with Bloomington Drosophila Stock Center (BDSC), working to develop a cryopreservation package for other stock centers and Drosophila labs, increasing the dissemination and impact of this work.

Pancreatic islet transplantation has the potential to facilitate a cure for diabetes, a debilitating disease that affects >34M people in the U.S. alone, and causes >83,000 deaths. However, a major barrier to islet transplantation is a lack of sufficient quantities of high-quality islets when and where they are needed. A successful islet transplantation typically requires on the order of 1 million islets, while a donor pancreas only yields 200,000 to 500,000 islets. This leads to a practical barrier that has limited the advancement of this life-saving approach. To address this, I redesigned the conduction-dominated cryomesh for cryopreservation of clinical islet quantities (>1 million islets) with high throughput at high viability > 85%. This project involves a close collaboration with the UMN Department of Surgery and the Mayo Clinic. We are now working on adapting these methods for clinical use and establishing appropriate partnerships to move this into the clinic.