Even though the direct nose-to-brain drug delivery has many clinical benefits, there are limited successes in delivering medication aerosols to the olfactory mucosa with standard inhalation devices. In this study, different delivery techniques were assessed in terms of their capacities to deliver drug aerosols to the olfactory epithelium. Specifically, the feasibility of electric field guidance of charged aerosols to the olfactory mucosa was evaluated in an image-based nose model both numerically and experimentally. Multi-sectional nasal cast replicas were fabricated using a 3-D printer to measure the olfactory deposition rates and visualize the deposition distributions. An intranasal deposition test platform was developed that comprised an electric field guidance system, a dry powder charging device, and a point-release nozzle. Numerical simulations were conducted using both ANSYS Fluent and COMSOL. We demonstrated that it is feasible to control charged particles inside the human nose use an external electric field. Both the point-release technique and electric field guidance of drug particles are essential in attaining optimal olfactory doses. Consistent deposition patterns were achieved between in vitro experiments and computational simulations. Future investigations are warrnated for further improvements of olfactory delivery through refining the particle generation, charging, and releasing, and navigation systems.
Part of the book: Advanced Technology for Delivering Therapeutics