Sterilization and material compatibility of 3D-printed devices for cell culture

Three-dimensional (3D) printing is increasingly used in cell biology to prototype custom cell culture devices, microscopy chambers, and other experimental hardware, but practical guidance on sterilization and material compatibility remains limited. Here, we develop and validate a low-temperature paraformaldehyde vapor sterilization method for fused filament fabrication (FFF) components that avoids heat-induced deformation. Using bacterial challenge assays with Escherichia coli and Geobacillus stearothermophilus, we confirm effective sterilization of 3D printed components. We also assess the effects of common filaments and adhesives on HL-60 human cell growth to identify materials suitable for cell culture workflows. Most untreated plastics were well tolerated over 48 hours, whereas some formaldehyde-treated materials required post-treatment with ammonia vapor to restore compatibility. Together, these results provide a practical framework for sterilizing and deploying 3D-printed materials in cell culture and biological research. Multidisciplinary Abstract3D printers allow laboratories to quickly make custom experimental equipment, but many printed materials cannot be sterilized using standard methods. We developed a low-temperature sterilization procedure using paraformaldehyde vapor and tested whether common printing materials and adhesives are compatible with cultured human cells. We identified several plastics, silicone-based adhesives and acrylic tapes that can be safely used after sterilization, while others require additional ammonia treatment. These results provide guidance for researchers using 3D printing to build custom laboratory and cell culture devices. Methods SummaryA low-temperature paraformaldehyde vapor sterilization method for 3D-printed FFF components was developed and validated using bacterial challenge assays. Compatibility of common printing filaments, adhesives, and tapes with cell culture workflows was assessed by exposing HL-60 cells to untreated, sterilized, and ammonia- neutralized materials and quantifying cell growth by flow cytometry.