The influence of formulation viscosity on device selection and ways spray pattern can be used as a screening tool to select an optimum device/formulation combination.
Evaluation of device/formulation compatibility during early development is key to producing a successful nasal spray product. However, traditional tests (such as shot weight) may provide limited information by focusing mainly on spray pump performance. Further, droplet size distribution testing may fail to provide accurate measurements for certain formulations, such as those based on ethanol. In contrast, spray pattern and plume geometry can offer comprehensive insight into overall spray characteristics via flow visualization and are highly sensitive to changes in critical parameters such as device design and formulation.