A recent study highlighted the development of model carrier microparticles for inhaled medicines, showcasing the innovative use of high-precision 3D laser printing technologies. This research, spearheaded by a team at Kiel University under the guidance of Professor Regina Scherließ, examined how microparticle geometry plays a crucial role in improving the efficiency of inhaled medications.

The Importance of Particle Geometry

Inhaled medications often rely on carrier particles to deliver active ingredients effectively into the lungs. The efficiency of this process depends significantly on the shape of the carrier particles. The study focused on four different particle designs, providing groundbreaking insights into their inhalation performance:

  • Pharmacone: A star-like geometry with protruding tips.
  • Soccerball: A spherical design mimicking a soccer ball.
  • Sphere: A classic spherical shape.
  • Rollingknot: A unique shape designed for specific aerodynamic properties.

Methodology: Two-Photon Polymerization

The research utilized a sophisticated method known as two-photon polymerization, which allows for the production of millions of identical microparticles with extreme precision. This technique, refined at the Karlsruhe Institute of Technology (KIT), facilitates the simultaneous creation of 49 structures, significantly speeding up the production process.

For testing, over two million identical particles were crafted for each design. These were then combined with a model drug, mimicking real inhalation conditions. The essential idea was to ensure that the active ingredients could detach effectively from the carriers during inhalation:

“For the drug to be effective, it has to detach from the carrier when inhaled and reach the lungs with the airflow,” explained first author Melvin Wostry.

Results: The Superior Performance of Pharmacone

The research findings underscored that particle shape dramatically influences drug release efficiency. In the tests, the 'Pharmacone' shape stood out as the most effective. The study reported the following results concerning the fine particle fraction:

Particle Design Fine Particle Fraction (<5 μm) Performance Comparison
Pharmacone Four times higher Best performing design
Soccerball Moderate Second best design
Sphere Lower Below average performance
Rollingknot Lowest Poor performance

The Role of Surface Roughness

Interestingly, the study also examined the effect of surface roughness on particle performance. It was discovered that varying levels of surface roughness did not significantly influence the detachment of the active ingredient. Thus, while fine-tuning geometry could increase effectiveness, surface texture should not be a primary concern in the development of these microparticles.

Future Applications and Pharmaceutical Potential

Though the carrier particles developed in this research currently serve as model systems for basic research, the implications for future pharmaceutical applications are significant. The potential for integrating such precisely engineered structures into dry powder inhalers could revolutionize inhalation therapies:

  • Integration of biodegradable carriers directly into inhalers.
  • Enhancements in the release profiles of therapeutic drugs.
  • Improved patient outcomes through more efficient inhalation delivery.

Professor Scherließ remarked on the transformative potential of high-resolution 3D printing in pharmaceutical development, stating,

“We can now deliberately influence the behavior of medications through design—a kind of fine-tuning on the micrometer scale.”

Conclusion

This study not only provides valuable insights into the mechanics of inhalation drug delivery but also expands the horizons of pharmaceutical engineering through the application of advanced 3D printing techniques. As research continues in this area, the possibilities for developing more effective inhaled medications appear to be limitless.

References

Wostry, M., et al. (2025). Aerodynamic performance of tailored microparticles as carriers in dry powder inhaler formulations made by multi-focus multi-photon 3D laser printing. Communications Materials. Retrieved from Science X.