Related Experiment Video
Updated: Aug 5, 2026
15:04
Modeling and Simulations of Olfactory Drug Delivery with Passive and Active Controls of Nasally Inhaled Pharmaceutical Aerosols
Published on: May 20, 2016
Nozzle Angle Optimization for Nasopharyngeal Drug Delivery: In Vitro Penetration Testing and Human Factors Usability
César Alas-Pineda1, Mohammad Mehedi Hasan Akash2,3, Abir Malakar2
1Department of Research and Development, Moxie Health Group, Hallandale Beach, USA.
Cureus
|July 29, 2026
Summary
A 12-15° nozzle angle significantly improves intranasal drug delivery to the nasopharynx compared to conventional angles. Lay users successfully followed the optimized protocol for effective nasal spray administration.
Area of Science:
- Pharmaceutical Sciences
- Biomedical Engineering
- Drug Delivery Systems
Background:
- Intranasal drug delivery presents a noninvasive administration route.
- Limited research exists on the impact of nozzle angle on nasopharyngeal deposition.
Purpose of the Study:
- To evaluate nozzle angle as a critical factor for posterior nasopharyngeal deposition.
- To assess the feasibility and human factors of an optimized intranasal spray protocol.
Main Methods:
- In vitro: Quantified nasopharyngeal outflow using a 3D-printed nasal cast with a pump sprayer at 12-15° and 67.5° nozzle orientations.
- Human Factors: Assessed a nine-step application protocol among 191 lay users in simulated and real-use scenarios.
Main Results:
- The 12-15° nozzle angle significantly increased nasopharyngeal penetration compared to the 67.5° angle in both nostrils (p < 0.019).
- All essential steps of the application protocol were completed with >80% fidelity by lay users, exceeding acceptance thresholds.
Conclusions:
- A 12-15° nozzle angle enhances nasopharyngeal deposition in a model system.
- Lay users demonstrated acceptable adherence to the optimized intranasal spray protocol.
- Further validation in diverse anatomical models and clinical settings is recommended.
Related Concept Videos
01:29Suctioning the Nasopharyngeal Airway
Nasopharyngeal suctioning is a procedure to remove secretions from the upper part of the respiratory tract that the patient cannot clear independently. It helps maintain airway patency and prevents complications such as aspiration pneumonia.
Equipment Required
Equipment Required
01:28Pipe Flowrate Measurement: Problem Solving
A spray tank system is engineered to uniformly distribute a pest-control liquid across plants by using a pressurized mechanism. The tank, pressurized to 150 kPa, holds the pesticide at a height of 0.80 meters. Liquid flows from the tank through a 1.9 meter pipe with a diameter of 0.015 meters, angled at 0.698 radians, ultimately reaching a 0.007 meter nozzle that sprays the pesticide. Accurate calculation of the system's flow rate is crucial to ensure uniform application, and this is achieved...