MSc thesis project proposal

Development of EHDA-based inhalation device: implementation of process monitoring and electronic parts

The electrohydrodynamic atomization (EDHA) or electrospraying of liquid solutions is a technique developed to produce micro and nano droplets. It consists of breaking a charged liquid jet up into droplets in an applied electrical field. This technique has been widely studied and used as an ionization source for mass spectroscopy and nanotechnology.

One of the most promising fields in which EDHA could be applied is drug delivery in patients with pulmonary diseases, specifically cystic fibrosis. One of the effective cures for the genetic disease of cystic fibrosis is to directly administrate the drug using an inhalation device. However the existing devices are not very patient friendly because of the timely administration required, side effects or overdosage...

By using the proposed EHDA-based technique we expect to deliver monodisperse particles of a particular size (controlled mainly by flow rate) in a significantly shorter time. Using only the conventional EHDA, evaporation of the electro-sprayed charged droplets - while forming particles - causes Coulomb fission. Coulomb fission results in poly-dispersity and unpredicted particle size. To tackle this problem, we modulate the charge density of the electro-sprayed droplets by introducing an ionic wind along the spray.

In this research we are developing the ionic wind assisted EDHA-based inhalation device to deliver the right particle size with the narrowest size distribution to target the affected areas in the patients� lung in a significantly shorter administration time.

One of the current challenges we are facing in the application of this technique is controlling the stability of the electro-spraying process. The instability in the process is mainly caused by lack of precisely controlled flow rate, electrical potentials and electrical currents. Characteristics of liquids such as its surface tension and conductivity in such a complex electrical field also adds to this problem.

Assignment

In this project, you will explore the possibilities of monitoring and controlling the process stability and will implement the necessary electronic units. Typically, the electric field properties, current, etc are important variables and need to be precisely set and measured to ensure stable production.

The electrically-charged droplets and ions make it difficult to predict the right conditions for spraying. For different electrospraying configurations, prediction of the strength and direction of the electrical field, ionic winds will be made using COMSOL Multiphysics modeling software. Based on these predictions, different device configurations will be explored experimentally. A prototype inhaler will be used to verify the performance of the device. Adaptations will be tested and evaluated.

The resulting droplet size, final particle size and size distribution of different liquids - from pure ethanol to antibiotic solutions � will be measured to evaluate the process in each device configuration.

This multidisciplinary research is in collaboration with Utrecht Medical Center (formulation development and future patient studies), Delft University of Technology (Section Bioelectronics for device development), and Chemical Engineering (for process development).

Requirements

If you are interested in challenging yourself in a multidisciplinary research subject with a practical application, please contact Prof. dr. Reza Lotfi (r.lotfi@tudelft.nl) or Dr. ir. W. A. Serdijn (w.a.serdijn@tudelft.nl).

Contact

prof.dr. Reza Lotfi

Bioelectronics Group

Department of Microelectronics

Last modified: 2017-07-10