Development and validation of material selection method for cost-effective lab-scale 3D-printed platforms in biotechnology.

Additive manufacturing is increasingly explored in microbial biotechnology, offering cost-effective, customizable, and scalable solutions. However, the lack of standardized methods for evaluating 3D-printed materials in microbial cultivation applications limits their broader adoption. This study proposes a reproducible framework to assess 3D-printed materials, integrating printability, autoclavability, mechanical testing (Shore D hardness and 3-point bending), and microbial biocompatibility testing. Five polylactic acid (PLA) filaments and twelve photopolymer resins were evaluated. Two polylactic acid filaments were identified as suitable for single-use applications, while a biocompatible photopolymer resin demonstrated potential for reusable components. Autoclaving emerged as the most critical step, eliminating half of the tested materials due to cracking or degradation. Notably, cost-efficient materials (e.g., eSun Standard Peach Pink and Elegoo plant-based Tough Grey resin) performed comparably to high-priced alternatives within the scope of microbial biotechnology. The method's applicability was validated by 3D-printing shake flasks using Fused Deposition Modelling and Stereolithography, which achieved microbial cultivation outcomes with Escherichia coli comparable to glass flasks. This work underscores the importance of robust material selection criteria and provides a systematic framework for advancing additive manufacturing in microbial biotechnology.