The mucus barrier is a secretion that lines the lung airways, surface of the eye, gastrointestinal tract and female reproductive system to protect them from infection but it also hindered treatment of diseases such as cystic fibrosis (CF).
Now a drug delivery system has been developed to overcome this, according to research presented at the 236th National Meeting of the American Chemical Society.
Dr Samuel Lai, lead presenter of the research, said: “We studied the properties of disease-causing viruses that evolved to infect mucosal surfaces to engineer a coating that enables our drug delivery particles to penetrate mucus layers in minutes.
“In our new work, we have improved the coatings considerably to allow faster penetration for a wider array of particle sizes."
By investigating how disease-causing viruses are able to pass through the mucus barrier the researchers discovered a technique for the delivery of therapeutics.
The researchers found that the pores in the barrier were larger than previously thought, providing a route for small particles that do not adhere to mucus.
Coating individual drug particles with polyethylene glycol (PEG) was found to enable therapeutics to penetrate the mucus barrier in the same manner as viruses.
PEG is a polymer that has been approved for use in humans by the US Food and Drug Administration (FDA) for over 25 years, which should ensure the drug delivery system does not fall foul of regulatory barriers.
The technology has the potential to improve the treatment of diseases affecting the mucosal surface including CF, cervical cancer and chronic sinusitis.
In particular, the treatment of CF and chronic sinusitis is hampered by the thickening of the mucus barrier that is associated with these diseases.
Side effects could also be reduced as the system more specifically targets the mucosal membrane.
In the treatment of cervical cancer, therapeutics could be applied topically to the female reproductive tract. This would allow high concentrations of chemotherapy to be applied to the affected area over a long period of time, without damaging other areas of the body.
The researchers intend to further refine the targeting of drugs, with Lai saying: “Eventually, we seek to engineer systems where a drug could be delivered to a specific tissue or set of cells anywhere in the body – we want to make that possible."