Device and method for creating aerosols for drug delivery
A drug delivery device is disclosed which produces aerosolized particles of pharmaceutically active drug for delivery to a patient by inhalation. The device includes a liquid feeding source such as a channel to which formulation is added at one end and expelled through an exit opening. The feeding channel is surrounded by a pressurized chamber into which gas is fed and out of which gas is expelled from an opening. The opening from which the gas is expelled is positioned directly in front of the flow path of liquid expelled from the feeding channel. Various parameters are adjusted so that pressurized gas surrounds liquid flowing out of the feeding channel in a manner so as to maintain a stable capillary microjet of liquid until the liquid exits the pressure chamber opening and is aerosolized into particles having a uniform diameter in the range of about 1 to 5 microns.
1. A device for aerosol drug delivery in operation, comprising:
a feeding source having flowing there through a pharmaceutically active, liquid drug which drug is, during operation, being expelled from an exit opening of the feeding source as a liquid stream: and
a pressure chamber having flowing there through to an exit orifice, a gas which surrounds the liquid stream and exits the orifice located downstream of a flow path of the liquid stream expelled from the exit opening of the feeding source;
wherein the exit opening of the feeding source is separated by a distance from about 0.002 mm to about 2 mm from the exit orifice of the pressure chamber;
wherein the liquid stream is, during operation of the device, substantially smaller in size then the diameter of the exit orifice of the pressure chamber;
wherein the feeding source has a circular exit opening with a diameter in a range of about 0.002 mm to about 2 mm;
wherein the exit orifice of the pressure chamber does not require cleaning, and does not require replacement.
2. The device of claim 1 , wherein the device is a hand-held, self-contained portable drug delivery device.
3. The device of Claim 1 , wherein, during operation of the device, the liquid stream exits the pressure chamber forming particles having an aerodynamic diameter in range of from 0.1 micron to about 10 microns and the exit orifice of the pressure chamber has a diameter in a range of about 0.002 mm to about 2 mm.
4. The device of claim 1 , wherein the liquid stream exits the pressure chamber forming particles having an aerodynamic diameter in a range of from 1 to 3 microns.
5. The device of claim 4 wherein the pharmaceutically active liquid drug is a suspension.
6. The device of claim 4 wherein the pharmaceutically active, liquid drug is a solution.
7. The device of claim 1 , wherein the liquid drug has a viscosity in a range of from about 10 −4 to about 1 kg/m/sec.
8. The device of claim 1 , wherein the gas is air.
9. The device of claim 1 , wherein the gas is CO 2 .
10. The device of claim 1 , wherein the exit opening has a diameter in the range of from about 0.01 mm to about 0.4 mm.
11. The device of claim 1 , wherein the liquid drug fed through the feeding source at any given point in time has a volume in the range of 5 microliters to 10,000 microliter.
12. The device of claim 1 , wherein gas forced into an area around the feeding source outlet has a pressure above 10 mBar above atmospheric pressure.
13. The device of claim 1 , wherein gas forced into an area around the feeding source outlet has a pressure below 50,000 mBar above atmospheric pressure.
14. A multi-source drug delivery device in operation comprising:
a plurality of feeding sources which, during operation of the device, each having flowing there through a liquid drug formulation which drug is expelled from each exit opening of each feeding source; and
at least one pressure chamber containing a pressurized gas, comprising an exit orifice configured such that the gas and drug exit downstream of a flow path of the drug expelled from each of the exit openings of each feeding source;
wherein the exit opening of each feed source is separated by a distance of from about 0.002 mm to about 2 mm from an exit orifice of a pressure chamber;
wherein the liquid formulation fed through each feeding source has a volume in the range of 5 microliters to 10,000 microliters;
wherein the device produces multiple stream of aerosol;
wherein a sufficient amount of formulation can be aerosolized in a sufficiently short period of time that the patient can, in a single inhalation, inhale all of the aerosol needed for a dose of the drug being delivered.
15. The device of claim 14 , wherein during operation of the device, the drug and gas exiting the pressure chamber comprises particles having an aerodynamic diameter in a range of from 0.1 micron to about 10 microns.
16. The device of claim 14 , wherein the drug and gas exiting the pressure chamber comprises particles having an aerodynamic diameter in a range of from 1 to 5 microns.
17. The device of claim 14 , wherein the pharmaceutically active drug is a solution.
18. The device of claim 14 , wherein the pharmaceutically active drug is a suspension.
19. The device of claim 14 , wherein the gas is chosen from air and CO 2 .
20. The device of claim 19 , wherein the exit opening has a diameter in the range of from about 0.01 mm to about 0.4 mm.
21. The device of claim 14 , wherein gas is forced into an area around the feeding source outlet at a pressure above 10 mBar above atmospheric pressure.
22. The device of claim 14 , wherein gas is forced into an area around the feeding source outlet at a pressure below 50,000 mBar above atmospheric pressure.