Solvent-free temperature-facilitated direct extrusion 3D printing for pharmaceuticals

Area of Science:

• Pharmaceutical Technology
• Materials Science
• Digital Health

Background:

• Direct extrusion 3D printing offers personalized medicine but often requires high temperatures or solvents, necessitating a drying step.
• Drying can compromise moisture- or temperature-sensitive drugs and complicate quality control in 3D printed dosage forms.

Purpose of the Study:

• To develop a simplified direct extrusion 3D printing process for solid dosage forms.
• To eliminate the post-printing drying step by incorporating glyceryl monostearate (GMS).

Main Methods:

• Rheological studies were conducted on theophylline and methacrylate polymer blends with GMS and triethyl citrate at 90°C.
• X-ray powder diffraction was used to analyze GMS miscibility in the polymer matrix.
• 3D printed tablets were evaluated for weight, content uniformity, mechanical resistance, and in vitro drug release.

Main Results:

• Addition of GMS and triethyl citrate significantly reduced extensional viscosity, facilitating printing.
• GMS exhibited dual behavior: plasticizer/lubricant at printing temperatures (90-110°C) and solidification aid at room temperature.
• 3D printed tablets met compendial standards for uniformity and mechanical strength, with drug release dependent on polymer ratios.

Conclusions:

• A simplified, low-cost 3D printing method for bespoke tablets was developed, avoiding high temperatures and post-printing drying.
• This approach enhances the feasibility of on-demand manufacturing for sensitive pharmaceutical compounds.
• The use of GMS offers a facile route to overcome limitations in current direct extrusion 3D printing techniques.