Open-source three-dimensional printing of biodegradable polymer scaffolds for tissue engineering

Abstract

The fabrication of scaffolds for tissue engineering requires elements of customization depending on the application and is often limited due to the flexibility of the processing technique. This investigation seeks to address this obstacle by utilizing an open-source three-dimensional printing (3DP) system that allows vast customizability and facilitates reproduction of experiments. The effects of processing parameters on printed poly(e-caprolactone) scaffolds with uniform and gradient pore architectures have been characterized with respect to fiber and pore morphology and mechanical properties. The results demonstrate the ability to tailor the fiber diameter, pore size, and porosity through modification of pressure, printing speed, and programmed fiber spacing. A model was also used to predict the compressive mechanical properties of uniform and gradient scaffolds, and it was found that modulus and yield strength declined with increasing porosity. The use of open-source 3DP technologies for printing tissue-engineering scaffolds provides a flexible system that can be readily modified at a low cost and is supported by community documentation. In this manner, the 3DP system is more accessible to the scientific community, which further facilitates the translation of these technologies toward successful tissue-engineering strategies.

Extrusion-based 3D printing of poly(propylene fumarate) scaffolds with hydroxyapatite gradients

“…Porosity was quantified (n = 5 per formulation) using gravimetric analysis following previous methods [34]. Briefly, sample dimensions (length, L; width, W; thickness, H) and mass (m scaffold ) were measured and used to calculate the porosity according to Equation 2, where ρ scaffold is the scaffold density and ρ material is the density of the material.…”

“…We did not evaluate the compressive mechanical properties of the bilayer and gradient scaffolds due to their lack of pore interconnectivity. 10 mm length × 10 mm width × 2.5 mm height (approximate scaffold thickness) scaffolds were compressed perpendicular to their short axis at a cross-head speed of 0.5 mm/min after an initial pre-load of 25 N, following previous work [34]. The compressive modulus (elastic region between a fixed strain of 0.20–0.30 %, Poisson ratio = 0.5) was calculated using a Python script (see Supplemental Information) [36, 37].…”

“…A one-way analysis of variance (ANOVA) was used to calculate differences among groups, with post-hoc analysis performed via Tukey's Honestly Significant Difference (HSD), where p-values (p < 0.05) were considered statistically significant. Statistical analysis was performed using Microsoft Excel (Microsoft Corporation, Redmond, WA) and JMP Pro 10 software (SAS Institute Inc., Cary, NC) following previous methods [15, 34]. …”

Open Source Multi-Head 3D Printer for Polymer-Metal Composite Component Manufacturing

“…Printable polymer material characterization has increased the knowledge available to engineers for common PLA and ABS materials [6][7][8][9] along with an increasing list of thermoplastics [10,11], polymer metal composite materials [12][13][14] and polymer ceramic composite materials [15][16][17][18] for a number of novel applications, including medical and health-related components [19][20][21][22][23]. Subsequently, advancements in material understanding has led to the development of more sophisticated RepRap machines.…”

The Setup Design for Selective Laser Sintering of High-Temperature Polymer Materials with the Alignment Control System of Layer Deposition

“…The SLS makes it possible to manufacture products with a unique internal and/or external surface shape and perspective physical and mechanical properties [1][2][3][4][5]. At the same time, there are a number of promising polymer powder materials that differ from those traditionally and long used in the technology of SLS-nylon [6,7], polycarbonate [8][9][10][11][12], polyamides [13][14][15][16][17], polyethylenes [18,19], or ferrielectric polyvinylidene fluorides [20] and so on-by a combination of high heat resistance, durability, and a wide range of interesting physic-mechanical and chemical-biological properties [21][22][23][24][25][26].…”