Citrus fruit analysis sparks idea for disposable inhaled drug delivery device
A team working out of the University of Central Florida opened the door to the new delivery method by characterizing how orange peels create microjets. These microjects are used by bartenders to add an orange twist to drinks but the underlying mechanism could also reshape how drugs are delivered.
In citrus fruits, microjects emerge when pressure tears open a tiny section of the peel to release oil stored in microscopic reservoirs below the surface, found a study published in the Proceedings from the National Academy of Sciences. The microjects exit the reservoirs at an average of 22 miles per hour.
The process suggests an alternative way to generate microjects in drug delivery applications. Today, the generation of microjects is underpinned by complex, precision-engineered components, such as piezoelectric drivers and microfabricated nozzles. The citrus-inspired approach would be simpler.
“The lightweight foam pad would come wrapped in a plastic pouch and protected from bending by a cardboard sleeve. To use, the foam is extracted from its sleeve and positioned near the mouth,” Andrew Dickerson, one of the authors of the study, told us.
“The user gives it a little squeeze, as if folding the foam pad in two. Jets burst from the shiny, thin membrane covering one side of the pad. The jets create a brief fine mist easily inhaled by the user.”
Dickerson’s vision dispenses with the expensive, complex microjet technologies used today in favor of drug reservoirs that burst forth under pressure. This simpler, cheaper approach could enable the creation of single-use emergency inhalers suitable for use in public clinics or remote villages.
Similarly, the compact, low-weight form of the envisaged delivery devices would make them suitable for use in first-aid kits or by people who need to carry emergency inhalers. Dickerson thinks it would be possible to deliver most liquids using the device, provided they are neither too volatile nor too viscous.
Next steps
The idea remains some way from being realized, though. Before that happens, Dickerson and his collaborators need to work out how to make the droplet size and dose delivered via the microjects consistent enough for medical applications.
Dickerson thinks it will take about a year to work through these issues and have a working prototype ready for testing. However, as it stands, it is unclear whether that work will get done.
“At the current time I don’t have any plans to develop the research further, but this could change if I find an industry partner with some resources,” said Dickerson.
