Effect of nozzle shape and applied load on jet injection efficiency

Abstract

In this paper we present new results on jet injection with the overall aim of providing an efficient drug delivery into the intradermal region of the skin. To advance upon previous work in this area, we studied the use of various geometries for the nozzle (ampule) tip, which is applied to the skin. The geometries included a regular (flat-top) nozzle, tapered nozzles (conical and parabolic), and one wide base nozzle in order to vary the local stress in the skin layers directly beneath the injector. In all of these geometries, we also varied both the applied load and the skin support (e.g., solid backing vs. porcine tissue). We found that the use of applied load combined with a wider contact area led to more consistent injections with dispersion characteristics that may be preferable for vaccinations utilizing skin-based electroporation.