Repositories for aquatic germplasm are essential for safeguarding valuable genetic diversity for species relevant to aquaculture, biomedical research, and conservation. Development of aquatic germplasm repositories is impeded by a lack of standardization within laboratories and across the research community. A great challenge among communities participating in germplasm repository development is to obtain suitable cryopreservation equipment and devices. Commercial programmable freezers are costly and thus unaffordable to many users. Self-made devices have substantial variability among users, resulting in few opportunities for standardization across communities. The development of open hardware with the increasing accessibility of three-dimensional (3-D) printing offers rapid prototyping and easy fabrication of devices by users around the world at low cost. The present work explored the feasibility of developing operational prototypes of 3-D printed motorized cryopreservation devices for continuous freezing of non-batched samples. A controlled cooling conveyor device (CCCD) was protptyped to cryopreserve sperm samples in straws that were loaded onto chain links suspended over liquid nitrogen held in a Styrofoam box. Cooling rates of 5 to 34 °C/min for 0.5-ml French straws were produced by adjusting the height of conveyor chains, slopes, and liquid nitrogen mass. The plunge temperature (-47 °C to -61 °C) was controlled by adjustment of conveyor speed. The cooling curves from the CCCD were comparable to a commercial programmable freezer. There were no significant differences in post-thaw motility of sperm from ornamental (Koi) common carp (Cyprinus carpio) among samples frozen with the CCCD and those frozen with a commercial programmable freezer. The post-thaw sperm motility was consistent among samples frozen in the CCCD across a 15-min time span. The CCCD prototypes in the present study proved to be feasible and functional as low-cost, customizable, portable, and yet standardizable options for freezing of individual (non-batched) samples. Additional designs can be developed through community efforts to facilitate further adoption and standardization. Details for the development, testing, assembling, and usage can be found in the publication: Liu, Yue, Melissa Eskridge, Amy Guitreau, Jacob Beckham, Megan Chesnut, Leticia Torres, Terrence R. Tiersch, and William Todd Monroe. "Development of an open hardware 3-D printed conveyor device for continuous cryopreservation of non-batched samples." Aquacultural Engineering 95 (2021): 102202 (https://www.sciencedirect.com/science/article/abs/pii/S0144860921000583). The development process of this work can be found in Melissa Eskridge’s thesis (https://digitalcommons.lsu.edu/gradschool_theses/4551/). This data set includes ‘stl’ files that can be used for 3D printing, and ‘ipt’ modeling files (Autodesk Inventor) that can be used for design modifications. These prototypes were developed by the Aquatic Germplasm and Genetic Resources Center (AGGRC, www.aggrc.com) at the Louisiana State University Agricultural Center. This hardware was originally designed by Melissa Eskridge with additional contributions from Yue Liu, Amy Guitreau, Jacob Beckham, Megan Chesnut, Leticia Torres, W. Todd Monroe, and Terrence R. Tiersch. This work was funded in part by the NIH Office of Research Infrastructure Program (ORIP). This device is part of a multi-year project to develop a series of open hardware to support development of standardized and reproducible tools for the research communities that use aquatic models to study human diseases. Please visit www.aggrc.com to learn more about our work. The mission of the AGGRC is to provide global leadership for development of germplasm repositories and commercialization of genetic resources for aquatic species through interdisciplinary collaboration. Rather than positioning the AGGRC as a central global repository, our approach is instead to develop technologies and practices and provide services necessary to empower the multiple and diverse communities within aquatic species to establish their own germplasm repositories. Currently most work directly addresses the pervasive lack of standardization and reproducibility that characterizes cryopreservation within aquatic species. These problems have slowed research through inefficiency and failure. Overall, although cryopreservation is possible at a research scale, it is not being utilized to near full potential for development of repositories or repository networks. The Center has 25+ years of experience working with numerous colleagues across hundreds of aquatic species and user communities addressing aquaculture, wild fisheries, conservation, and biomedical models. Based on this experience concerning the problems and opportunities for aquatic species, the AGGRC is organized across four core program areas that span user needs from research through industrial-scale application.

All Fusion 360 files can be found on our GitHub through the following link:

https://github.com/aggrc/Controlled-Cooling-Conveyor-Device-CCCD-V1.0.0