Accessible melt electrowriting three-dimensional printer for fabricating high-precision scaffolds

Melt electrowriting (MEW) is an established 3D printing technology for producing high-resolution scaffolds for tissue engineering. Commercial MEW devices are expensive while having limited processing capabilities, which limits their accessibility and widespread use. Herein, we report an easy-to-assemble and inexpensive ($2000) MEW printer based on an off-the-shelf automated dispensing machine with user-friendly controls and a custom- designed MEW printhead capable of printing polymers with a melting point of up to 260 degrees C. Using the gold standard printable material, poly(epsilon-caprolactone) (PCL), this printer can deposit 3 mu m diameter fibers at 50 mu m spacing, demonstrating that the highest quality of scaffolds can be produced on the low-cost MEW system. Stability in printing is improved by maintaining a relative humidity of 30-35 %, ensuring nozzle conditions are optimal, and minimizing bubbles in the polymer melt. Key printing parameters such as a 3 kV applied voltage, 75 degrees C heating temperature, 100 kPa air pressure, and 30 G nozzle size are critical for high accuracy, achieving 100 mu m fiber spacing and layer stacking up to 30 layers without fiber breakage. The printer effectively creates complex scaffold geometries, showcasing its precision and suitability for advanced tissue engineering applications. Overall, this study promotes low-cost MEW technology by establishing a guideline on building an accessible but capable MEW printer and providing a crucial experimental foundation toward achieving high-accuracy scaffolds.