Previously it could not be explained why during drug development inhaled drug nanoparticles sometimes not arrived at target site of action in the lung cells but simply got stuck in the mucus. "The lungs´ mucus is a special gel. The construction is totally different from other gels, "said Claus-Michael Lehr, Professor of Biopharmaceutics and Pharmaceutical Technology of the Saarland University and head of the Department Drug Delivery at the HIPS.
"Normal" gels have a micro-structure that resembles an filigree spider web of thin, fine strands which enclose small pores. When looking through the microscope, the lung mucus appear like a sponge: stiff, thick gel rods separate large, fluid-filled pores. "These scaffold proteins are called mucins," explains Professor Lehr. The researchers have demonstrated that nanoparticles remain attached to these structures as to cage bars. "Our results help us to understand how infectious diseases of the respiratory tract develop and how they can be combated more effectively. They are a particularly important basis for the development of inhalable medications", explaines Professor Lehr. The results deepen our understanding of respiratory diseases, particularly of infections, and support the development of new drugs for inhalation. The scientists published their their findings in the prestigious journal Proceedings of the National Academy of Sciences (PNAS).
Source and further information (in German): http://www.helmholtz-hzi.de/
Original publication:
Julian Kirch, Andreas Schneider, Berengere Abou, Alexander Hopf, Ulrich F. Schaefer, Marc Schneider, Christian sound, Christian Wagner and Claus-Michael Lehr (2012): Optical tweezers reveal relationship between microstructure and nanoparticle penetration of pulmonary mucus. PNAS.