Biocompatibility and customizability: Expanding possibilities with 3D printed guide cannulas

Area of Science:

• Neuroscience
• Biomedical Engineering
• Materials Science

Background:

• Intracerebral cannulation is crucial for targeted drug delivery to brain structures.
• Traditional stainless steel guide cannulas are widely used despite limitations.
• Existing methods for guide cannula fabrication have been previously published.

Purpose of the Study:

• To introduce a novel method for producing fully plastic guide cannulas for intracerebroventricular injections in mice.
• To assess the biocompatibility and performance of 3D-printed plastic cannulas.
• To provide accessible and customizable tools for neuroscience research.

Main Methods:

• Utilized Dental Sand A1-A2 resin and digital light processing 3D printing to fabricate plastic guide cannulas.
• Assessed neurotoxicity using primary rat cortical neuron cultures.
• Performed histological evaluations in C57/black mice post-implantation.
• Compared performance with lab-made stainless steel cannulas over 3 weeks of daily injections.

Main Results:

• The 3D-printed plastic resin demonstrated no neurotoxicity.
• Plastic cannulas proved biocompatible, showing reduced microglial and astroglial reactions compared to stainless steel.
• Plastic cannulas exhibited superior resistance to obstruction, remaining functional for 3 weeks versus 2 weeks for stainless steel.
• The new cannulas feature usable threads for dummy cannula fixation and a low profile.

Conclusions:

• Editable parametric and STL files are provided for reproducibility.
• The described method is accessible, enabling standardization and customizability of guide cannulas.
• This innovation offers a promising alternative to traditional stainless steel cannulas for intracerebral drug delivery research.