Stabilized capillary microjet and devices and methods for producing same

• US 6,116,516 A
• Filed: 11/13/1998
• Issued: 09/12/2000
• Est. Priority Date: 05/13/1996
• Status: Expired due to Term

• Current Assignee: Universidad de Sevilla
• Original Assignee: Universidad de Sevilla
• Inventors: Ganan-Calvo, Alfonso
• Primary Examiner(s): Kashinkow, Andres
• Assistant Examiner(s): Ganey, Steven J.
• Application Number:
  US09/192,091
• Time in Patent Office: 669 Days
• Field of Search: 239/3, 239/8, 239/290, 239/291, 239/418, 239/419, 239/423, 239/424, 239/428, 239/338, 239/346, 73/53.01, 73/54.11, 73/1.02, 73/864.81, 261/76, 261/78.1, 261/78.2, 261/115, 261/116, 222/420, 128/200.21
• US Class Current: 239/8
• CPC Class Codes: A61M 11/001 Particle size control
• CPC Class Codes: A61M 11/002 by flow deviation causing inertial separation of transported particles
• CPC Class Codes: A61M 15/0065 Inhalators with dosage or measuring devices A61M15/0028 takes precedence; dosage devices incorporated in aerosol cans B65D83/52
• CPC Class Codes: A61M 15/025 Bubble jet droplet ejection devices
• CPC Class Codes: A61M 2202/064 Powder
• CPC Class Codes: B01F 23/232 using flow-mixing means for introducing the gases, e.g. baffles
• CPC Class Codes: B01F 25/30 Injector mixers mixing by creating vortex flow B01F25/10
• CPC Class Codes: B01F 33/3011 using a sheathing stream of a fluid surrounding a central stream of a different fluid, e.g. for reducing the cross-section of the central stream or to produce droplets from the central stream
• CPC Class Codes: B01J 2219/00378 Piezoelectric or ink jet dispensers
• CPC Class Codes: B05B 1/02 designed to produce a jet, spray, or other discharge of particular shape or nature, e.g. in single drops, or having an outlet of particular shapeB05B1/26, B05B1/28, B05B1/34 take precedence
• CPC Class Codes: B05B 7/0475 with means for deflecting the peripheral gas flow towards the central liquid flow B05B7/0458 takes precedence
• CPC Class Codes: B05B 7/061 with several liquid outlets discharging one or several liquids
• CPC Class Codes: B05B 7/065 an inner gas outlet being surrounded by an annular adjacent liquid outlet
• CPC Class Codes: B05B 7/066 with an inner liquid outlet surrounded by at least one annular gas outlet
• CPC Class Codes: B05B 7/0884 the outlet orifices for jets constituted by a liquid or a mixture containing a liquid being aligned
• CPC Class Codes: B82Y 10/00 Nanotechnology for information processing, storage or transmission, e.g. quantum computing or single electron logic
• CPC Class Codes: B82Y 30/00 Nanotechnology for materials or surface science, e.g. nanocomposites
• CPC Class Codes: C40B 60/14 for creating libraries
• CPC Class Codes: F02M 43/04 Injectors peculiar thereto
• CPC Class Codes: F02M 67/10 Injectors peculiar thereto, e.g. valve less type
• CPC Class Codes: F02M 69/047 : injectors with air chambers, e.g. communicating with atmosphere for aerating the nozzles F02M69/325 takes precedence
• CPC Class Codes: F02M 69/08 : characterised by the fuel being carried by compressed air into main stream of combustion-air
• CPC Class Codes: F23D 11/106 : medium and fuel meeting at the burner outlet
• CPC Class Codes: G01N 15/1409 : Handling samples, e.g. injecting samples
• CPC Class Codes: G01N 2015/1406 : Control of droplet point
• CPC Class Codes: G01N 21/01 : Arrangements or apparatus for facilitating the optical investigation
• CPC Class Codes: Y10S 977/773 : Nanoparticle, i.e. structure having three dimensions of 100 nm or less
• CPC Class Codes: Y10S 977/888 : Shaping or removal of materials, e.g. etching
• CPC Class Codes: Y10S 977/89 : Deposition of materials, e.g. coating, cvd, or ald
• CPC Class Codes: Y10S 977/896 : Chemical synthesis, e.g. chemical bonding or breaking

Abstract

The invention is directed to a stable capillary microjet and a monodisperse aerosol formed when the microjet dissociates. A variety of devices and methods are disclosed which allow for the formation of a stream of a first fluid (e.g. a liquid) characterized by forming a stable capillary microjet over a portion of the stream wherein the microjet portion of the stream is formed by a second fluid (e.g. a gas). The second fluid is preferably in a different state from the first fluid--liquid-gas or gas-liquid combinations. However, the first and second fluids may be two different fluids in miscible in each other. The stable capillary microjet comprises a diameter d_j at a given point A in the stream characterized by the formula: ##EQU1## wherein d_j is the diameter of the stable microjet, = indicates approximately equally to where an acceptable margin of error is ±10%, ρ₁ is the density of the liquid and ΔP_g is change in gas pressure of gas surrounding the stream at the point A.

Claims

1. A stream of a liquid characterized by forming a stable microjet over a portion of the stream wherein the stable microjet portion of the stream is formed by a gas moving at a velocity greater than that of the liquid:

wherein stable microjet comprises a diameter d_j at a given point A in the stream characterized by the formula;

##EQU19## wherein d_j is the diameter of the stable microjet, = indicates approximately equally to where an acceptable margin of error is plus or minus 10%, Q is the liquid flow rate, ρ

₁ is the density of the liquid and Δ

P_g is change in gas pressure of gas surrounding the stream from a pressure chamber to the point A.

2. The stream of claim 1, wherein d_j is a diameter in a range of about 1 micron to about 1 mm.

3. The stream of claim 1, wherein the stable capillary jet portion has a length in a range of from about 1 micron to about 50 mm.

4. The stream of claim 1, wherein the stable capillary microjet is maintained, at least in part, by tangential viscous stresses exerted by the gas on a surface of the jet in an axial direction of the jet.

5. The stream of claim 1, wherein the microjet is further characterized by a slightly parabolic axial velocity profile.

6. The stream of claim 1, wherein the Weber number is in a range of from about 1 to about 40 wherein the Weber number is defined by the following equation:

##EQU20## wherein ρ

_g is the density of the gas, d is the diameter of the stable microjet, γ

is the liquid-gas surface tension, and V_g² is the velocity of the gas squared.

7. The stream of claim 6, wherein the Weber number is in a range of from about 5 to about 25.

8. The stream of claim 1, wherein Ohnesorge number is less than one, wherein the Ohnesorge number (Oh) is defined by ##EQU21## wherein μ

₁ is the viscosity of liquid, ρ

₁ is the density of the liquid and d is the diameter of the stable capillary microjet.

9. The stream of claim 1, wherein the liquid of the stream comprises a pharmaceutically active drug.

10. A monodisperse aerosol of liquid particles in air, the particles characterized by having the same diameter with a deviation in diameter from one particle to another in a range of from about ±

3% to about ±

30% the particles being formed by the destabilization of a stream of a liquid characterized by forming a stable microjet over a portion of the stream wherein the stable microjet portion of the stream is formed by a gas moving at a velocity greater than that of the liquid;

wherein stable microjet comprises a diameter d_j at a given point A in the stream characterized by the formula;

##EQU22## wherein d_j is the diameter of the stable microjet, = indicates approximately equally to where an acceptable margin of error is plus or minus 10%, Q is the liquid flow rate, ρ

₁ is the density of the liquid and Δ

P_g is change in gas pressure of gas surrounding the stream from a pressure chamber to the point A.

11. The aerosol of claim 10, wherein the deviation in diameter from one particle to another is in a range of from about ±

3% to ±

10%.

12. The aerosol of claim 10, wherein a given particle in the aerosol has a diameter in a range of about 0.1 micron to about 100 microns and other particles in the aerosol have the same diameter as the given particle with a deviation of about ±

3% to about ±

30%.

13. The aerosol of claim 10, wherein the particles comprise a pharmaceutically active drug.

14. The aerosol of claim 10, wherein the particles have a diameter in a range of about 0.1 to 100 microns.

15. The aerosol of claim 10, wherein 90% or more of the particles have the same diameter with a margin of error in a range of ±

10%.

16. The aerosol of claim 10, wherein 90% or more of the particles have the same diameter with a margin of error in a range of ±

3%.

17. A method of analyzing a compound in a liquid, comprising the steps of:

applying physical pressure to force a first liquid through a channel of a feeding source in a manner which causes the first liquid to be expelled from an exit opening of the channel;

forcing a fluid selected from the group consisting of a gas and a second liquid which is immiscible with the first liquid through a pressure chamber in a manner which causes the fluid to exit the pressure chamber from an exit orifice in front of a flow path of the first liquid expelled from the exit opening of the channel, wherein a stable first liquid-fluid interface is maintained and the first liquid forms a stable capillary jet focused on the exit orifice of the pressure chamber;

emitting a pulse of energy through the stable capillary jet;

receiving energy from the pulse;

analyzing energy received to determine information regarding a compound in the first liquid.

18. The method of claim 17, wherein the energy is selected from the group consisting of infrared, and ultra violet.

19. The method of claim 18, wherein the fluid is a gas.

20. The method of claim 19, wherein stable capillary microjet comprises a diameter d_j at a given point A in the stream characterized by the formula:

##EQU23## wherein d_j is the diameter of the stable microjet, = indicates approximately equally to where an acceptable margin of error is ±

10%, ρ

₁ is the density of the liquid and Δ

P_g is change in gas pressure of gas surrounding the stream from the pressure chamber to the point A.

21. The stream of claim 20, wherein is a diameter in a range of about 1 nicron to about 1 mm.

22. The stream of claim 20, wherein the stable capillary jet portion has a length in a range of from about 1 micron to about 50 mm and wherein the stable capillary microjet is maintained, at least in part, by tangential viscous stresses exerted by the gas on a surface of the jet in an axial direction of the jet.