(65c) Electro-Hydrodynamic Encapsulation of Drugs Into Porous Polymer Films

To eliminate adverse effects of electro-chemical reactions at the fluid-electrode interface in the course of electro-hydrodynamic (EHD) deposition, a fluid specimen does not directly come in contact with electrodes (Appl Phys Lett 97, 233501, 2010). Once deposited, a droplet spreads over and imbibed into a porous film. Compared to inkjet technologies, droplet deposition was not accompanied by fluid flow through the nozzle. Due to this feature, the EHD method provides a precise control over the deposited droplet volume and the ability to deposit highly viscous fluids. To test the method feasibility, experiments were carried out on poorly water-soluble ibuprofen and griseofulvin and porous HPMC films prepared by freeze-drying. To prepare drug solutions for printing, ibuprofen and griseofulvin were dissolved in PEG 400. Viscosities of these solutions exceeded the operating range of commercially available inkjet print heads by a factor of 15-20. The positioning accuracy of liquid droplets was about 1.2%. The relative standard deviation of the mean weight of a drug solution printed to fabricate a dosage unit was about 0.78%. The results presented show that EHD DOD offers a powerful tool for the evolving field of small-scale pharmaceutical technologies for tailoring medicines to individual patient's needs by printing a vast array of predefined amounts of therapeutics arranged in a specific pattern on a porous film.

This work was supported by the NSF ERC for Structured Organic Particulate Systems