Biocompatible designated Resin-3D-printed polymers exhibit reproductive toxicity prevented by Parylene-C

Area of Science:

• Biomaterials Science
• Reproductive Biology
• 3D Printing Technology

Background:

• Resin 3D printing is valuable for microphysiological systems (MPS), but resin cytotoxicity limits its use with sensitive cells like oocytes.
• Oocytes and early embryos are highly sensitive, making them ideal models for stringent biomaterial biocompatibility testing.

Purpose of the Study:

• To develop and utilize a Multi-Endpoint Oocyte Safety Assay (MEIOSA) for evaluating the biocompatibility of 3D printed resins.
• To assess the cytotoxicity of four ISO 10993 biocompatible BioMed resins on mammalian oocytes during in vitro maturation (IVM).
• To investigate methods for mitigating resin cytotoxicity in 3D printed MPS.

Main Methods:

• Developed the MEIOSA to assess oocyte viability, morphology, meiotic stage, and meiotic spindle morphology after IVM.
• Cultured oocytes in plate inserts 3D printed with four different BioMed resins (Clear, Durable, Elastic 50A, Flex 80A).
• Applied a Parylene-C (PC) coating to the resin inserts to evaluate its protective effect against cytotoxicity.

Main Results:

• Oocytes cultured in rigid or elastomeric resins showed impaired meiotic progression and degeneration compared to polystyrene controls.
• PC coating completely rescued oocyte degeneration and meiotic defects across all tested resins.
• PC-coated Flex 80A resin supported fertilization-competent oocytes that developed into normal preimplantation embryos.

Conclusions:

• Standard viability tests may not detect all cytotoxic effects on sensitive cell types.
• MEIOSA is a sensitive assay for robust biomaterial biocompatibility evaluation.
• Parylene-C coating effectively prevents resin cytotoxicity, enabling the use of 3D printed materials for reproductive and other sensitive cell-based MPS.