Conduction Cooling and Plasmonic Heating Dramatically Increase Droplet Vitrification Volumes for Cell Cryopreservation

• Published in: Advanced science 2021-06, Vol.8 (11), p.2004605-n/a
• Main Authors: Zhan, Li, Guo, Shuang‐Zhuang, Kangas, Joseph, Shao, Qi, Shiao, Maple, Khosla, Kanav, Low, Walter C., McAlpine, Michael C., Bischof, John
• Format: Article
• Language: English
• Subjects: Biomedical materials; Cell Line; Cell Survival; cell therapy; Cells, Cultured; Cold Temperature; conduction cooling; Cryopreservation; Cryopreservation - methods; droplet vitrification; Fibroblasts - chemistry; Gold - chemistry; Heat transfer; Hot Temperature; Humans; Lasers; Methods; Nanotubes - chemistry; Nitrogen; plasmonic laser heating; Polyethylene glycol; Stem cells; Vitrification
• ISSN: 2198-3844; 2198-3844
• DOI: 10.1002/advs.202004605

Droplet vitrification has emerged as a promising ice‐free cryopreservation approach to provide a supply chain for off‐the‐shelf cell products in cell therapy and regenerative medicine applications. Translation of this approach requires the use of low concentration (i.e., low toxicity) permeable cryoprotectant agents (CPA) and high post cryopreservation viability (>90%), thereby demanding fast cooling and warming rates. Unfortunately, with traditional approaches using convective heat transfer, the droplet volumes that can be successfully vitrified and rewarmed are impractically small (i.e., 180 picoliter) for 400‐fold improvement in warming rates over traditional convective approach. High viability cryopreservation is then demonstrated in a model cell line (human dermal fibroblasts) and an important regenerative medicine cell line (human umbilical cord blood stem cells). This approach opens a new paradigm for cryopreservation and rewarming of dramatically larger volume droplets at lower CPA concentration for cell therapy and other regenerative medicine applications. A novel droplet vitrification system demonstrates high post thaw cell viability (90–95%) with reduced cryoprotectant concentration (i.e., 20%) and improved vitrification throughput (i.e., ≈1000x) using larger (1–4 μL) droplet volumes. Conductive cooling and plasmonic heating approaches are employed and characterized thoroughly to substantially improve the cooling and warming rates compared to traditional convective heat transfer approaches.