Biocompatibility of 3D printed plastics for use in bioreactors

Abstract

Three-dimensional (3D) printing has the potential to be used for rapid-prototyping and inexpensive fabrication of bioreactors for advanced cell and tissue culture. However, the suitability of materials used for 3D printing these bioreactors that will be in direct contact with cells and culture media remains to be established. Many of the most common low-cost materials have not been thoroughly tested under stringent cell culture conditions, especially not with highly sensitive human cell types, such as induced pluripotent stem cells (hiPSCs). This study aims to characterize some 3D printed plastics, such as thermoplastics and photopolymers, focusing on the toxicity/cytocompatibility of the materials as assessed by hiPSC viability, retention of pluripotency, and cardiogenic differentiation potential. Experiments were conducted in a manner that simulates contact between 3D printed plastics and cell culture media, as found in a 3D printed bioreactor. Both photopolymers tested here reduced the viability of hiPSCs, but not of primary human fibroblasts, highlighting the importance of carrying out these tests with the cells of interest. The thermoplastics did not adversely affect stem cell viability, pluripotency, or cardiac differentiation potential. However, except for Nylon12, all thermoplastics deformed during autoclaving, leading us to choose Nylon12 as the most suitable material for bioreactor fabrication. This study represents a step forward in the use of 3D printing for the rapid, low-cost fabrication of custom-designed bioreactors.