Droplet Based High Throughput Single-Sperm Cryopreservation Platform

With the popularization of assisted reproduction technology (ART), as a key technology in ART, cell cryopreservation still has great space for improvement. At present, there are few cryopreservation technologies suitable for rare cells. And these technologies have high requirements for operators. Therefore, there is a lack of easy-to-use single sperm cryopreservation techniques for oligospermia patients.Here we present a cryopreservation system that composed of thousands of pico-liter-volume droplets [1]. This platform enjoys the following advantages (1) Single cell level manipulation: The platform could realize single sperm cryopreservation. (2) High throughput: This chip could preserve 104 sperms separately in thousands of droplets. (3) Handleability: Droplets in microfluidic chips are easy to generate and extract. (4) Great performance: faster cryoprotectant agents (CPAs) loading and unloading, smaller cryopreservation volume could improve sperms survival rate [2],[3]. (5) Customizability: Different individuals, even sperms, could have different responses to CPAs. This platform could generate CPAs with gradient concentration to determine the optimum reagent formula.