Abstract
An aerosol concentrator dividing an input aerosol into a respirable aerosol of an increased particle concentration and an exhaust aerosol of a lower particle concentration. The concentrator comprises a cross-slit of an input tube and output tube with a gap between the cross-slits of input tube and the output tube. A housing encompasses a plenum which encompasses the gap and is connected to an exhaust port through which an exhaust aerosol exits the plenum. A radial size of the plenum is can be significantly larger than the length of the slits in the cross-slit.
Claims
1. An aerosol concentrator dividing an input aerosol of an input particle concentration into a concentrated respirable aerosol of an increased particle concentration that is higher than the input particle concentration and an exhaust aerosol of a lower particle concentration that is lower than the input particle concentration, said concentrator comprising: an input tube having a lumen and comprising: an input tube entrance port having an input tube entrance port cross-sectional shape differing from a cross-slit shape; an input tube exit port having a cross-slit shape, wherein the input tube entrance port cross-sectional shape transitions between the input tube entrance port and the input tube exit port to the cross-slit-shaped exit port cross-sectional shape; an output tube having a lumen and comprising: an output tube entrance port having a cross-slit-shaped cross-section, said output tube entrance port being aligned with and spaced apart from the input tube exit port by a gap between the input tube exit port and the output tube entrance port; an output tube exit port wherein the output tube entrance port cross-sectional shape transitions between the output tube entrance port and the output tube exit port to an output tube exit port cross-sectional shape; and a housing encompassing a plenum, said plenum encompassing the gap between the input tube and the output tube, wherein the plenum is connected to an exhaust port through which an exhaust aerosol exits the plenum.
2. The aerosol concentrator according to claim 1, wherein the input tube converges from its input tube entrance port to its input tube exit port from an input tube entrance port cross-sectional area that is larger than an input tube exit port cross-sectional area.
3. The aerosol concentrator according to claim 1, wherein the output tube diverges from its output tube entrance port to its output tube exit port from an output tube entrance port cross-sectional area that is smaller than an output tube exit port cross-sectional area.
4. The aerosol concentrator according to claim 1, wherein the input tube and the output tube have a joint longitudinal axis and have radial sizes transverse to the longitudinal axis that are less than a third of a radial size of the plenum transverse to said longitudinal axis.
5. The aerosol concentrator according to claim 1, wherein the housing compromises an input housing part holding the input tube, and output housing part holding the output tube and an exhaust tube, and a seal is provided between the input housing part and the output housing part.
6. The aerosol concentrator according to claim 5, wherein the housing shares the same joint longitudinal axis with the input tube and the output tube and the plenum is encompassed at least for the most part by either one of the input housing part or the output housing part, while the other part of the output or input housing, respectively, is essentially disc-shaped, with the housing part encompassing at least for the most part the plenum also having the exhaust tube which extends essentially radially in a transverse direction with respect to said longitudinal axis.
7. The aerosol concentrator according to claim 5, wherein a pressure relief valve is connected to the exhaust tube keeping the pressure within and across concentrator and consequently at the output tube exit port essentially constant.
8. The aerosol concentrator according to claim 7 wherein the concentrator is designed to concentrate an input aerosol having fine particles of a particle size distribution of 1-6 m MMAD suspended in gas.
9. The aerosol concentrator according to claim 1 wherein the concentrator is designed to concentrate an aerosol using virtual impaction at a small positive pressure within and across concentrator all the way to the output tube exit port such that the concentrated respirable aerosol can be delivered to the patient at the small positive pressure without the use of pumps to remove the exhausted gas.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
[0050] FIG. 1 is a block diagram of the components of the aerosol generation device.
[0051] FIG. 2 is a schematic diagram of the pneumatic system and aerosol generation device.
[0052] FIG. 3 shows an exploded view of the liquid dispenser system.
[0053] FIG. 4A shows the assembled perspective view of the dispenser system.
[0054] FIG. 4B shows an alternate exploded view of the dispenser system as shown in FIG. 3
[0055] FIG. 5A shows the side view of the dispenser cap.
[0056] FIG. 5B shows the longitudinal section denoted A-A in FIG. 5A.
[0057] FIG. 5C shows the top view of the dispenser cap.
[0058] FIG. 5D shows the vertical section denoted B-B in FIG. 5C.
[0059] FIG. 6A shows a perspective view of the nozzle.
[0060] FIG. 6B shows the side view of the nozzle.
[0061] FIG. 6C shows the sectional view denoted C-C in FIG. 6B.
[0062] FIG. 6D shows a detailed view of the section C-C showed in FIG. 6C.
[0063] FIG. 7A shows a perspective view of an assembly comprising a nozzle, aerosol chamber, counter flow tube, chamber pedestal, aerosol concentrator and flapper block.
[0064] FIG. 7B shows the top view of assembly in FIG. 7A.
[0065] FIG. 7C shows the sectional view denoted D-D in FIG. 7B.
[0066] FIG. 8A shows an assembled perspective view of the aerosol concentrator.
[0067] FIG. 8B shows an exploded view of the aerosol concentrator.
[0068] FIG. 8C shows the assembled side view of the aerosol concentrator.
[0069] FIG. 8D shows the sectional view denoted E-E in FIG. 8C.
[0070] FIG. 9A shows a perspective view of the flapper block.
[0071] FIG. 9B shows an exploded view of the flapper block.
[0072] FIG. 9C shows the top view of the flapper block.
[0073] FIG. 9D shows the sectional view denoted F-F in FIG. 9C.
[0074] FIG. 10 shows a plot of particle size versus flow rate for PVP solutions of different viscosities aerosolized using compressed air and a 500 m orifice nozzle.
[0075] FIG. 11 shows a plot of particle size versus flow rate for PVP solutions of different viscosities aerosolized using compressed heliox and a 500 m orifice nozzle.
[0076] FIG. 12 shows a plot of particle size versus flow rate for PVP solutions of different viscosities aerosolized at a lowered pressure using compressed air and a 500 m orifice nozzle.
[0077] FIG. 13 shows a plot of particle size versus flow rate for PVP solutions with different viscosities are aerosolized using compressed air and a 700 m orifice nozzle.
[0078] FIG. 14 shows a three-axis plot particle size versus flow rate and particle size versus span, when with a 500 m orifice nozzle water is (i) aerosolized using compressed air, and (ii) aerosolized using heliox.
DETAILED DESCRIPTION OF THE DRAWINGS
[0079] FIG. 1 is a block diagram schematically demonstrating the components of the aerosol generation device. The invention comprises a console 1 and its components which interact with the patient/clinician via a patient/clinician interface 2 to deliver precise doses of aqueous aerosols as shown in FIG. 1. The console 1 may comprise the patient/clinician interface 2, microcontroller 3, hardware controller 4 and internal hardware 5. Several components, including the liquid dispenser 6, aerosol nozzle 7, counterflow tube 8 and the aerosol delivery respiratory support 9, are pneumatically controlled by the hardware controller 4 which comprises solenoid valves that are triggered by the microcontroller 3. The settings for the microcontroller 3 and internal hardware 5 may be set in accordance with a prescribed dosage. When the patient/clinician initiates the therapy via the patient/clinician interface 2, the microcontroller 3 interacts with the hardware controller 4 to effect aerosol output. The aerosol chamber 10 comprises the aerosol nozzle 7 and the counterflow tube 8, both of which are housed therein. The aerosol chamber 10 is configured to focus the aerosol generated by the nozzle 7 downstream. The aerosol delivery respiratory support 9 enables delivery of the aerosol to the patient, and ensures aerosol is only delivered during inhalation.
[0080] FIG. 2 schematically shows the system according to the invention. Compressed air or heliox is supplied to the system by a high-pressure source 20, and regulated by a system pressure regulator 21, which is connected in series with the high-pressure source 20. This stable and regulated pressure is then distributed downstream to the constituent systems through a gas supply line network.
[0081] Pressure may be routed to a liquid vial 23 through a gas supply line 13, along which a liquid pressure regulator 22 and a 3-2-way solenoid valve 24 are disposed. The liquid pressure regulator 22 may be configured to pressurize the liquid vial 23, which supplies liquid to the aerosol nozzle 7 via a liquid supply line 11. A 3-2-way solenoid valve V1 24 may be disposed between the liquid pressure regulator 22 and the liquid vial 23 to control the flow of liquid from the liquid vial 23 to the nozzle liquid input 60 of the nozzle 7. In a preferred embodiment, the 3/2-way solenoid valve 24 is by default in a closed position, and prior to aerosolization may switch to an open position, thereby turning the pressure on.
[0082] The system may additionally include a three-way solenoid valve 26 configured to control the flow of liquid within the liquid microchannel 70 inside the nozzle barrel 66. Regulated pressures from the system pressure regulator 21 and a nozzle gas regulator 25 are routed through the three-way solenoid valve 26. The pressures P, P1 and P2 respectively corresponding to the system regulator R 21, liquid pressure regulator R1 22 and nozzle gas regulator R2 25, are adjusted such that P>P1>P2. When the V2 26 is open to pressure P from regulator R 21, the pressurized liquid flow in the aerosol nozzle 7 is arrested. However, when the V2 26 is open to pressure P2 from regulator R2 25, the liquid flows through the aerosol nozzle 7 for aerosolization.
[0083] Pressure may be routed to counterflow tube 8 via a counterflow gas tube supply line 14 and expelled out of a counterflow gas tube exit opening 16. A counterflow tube regulator 27 may be included to control the gas pressure in the counterflow tube 8. A second 3-2-way solenoid valve 28 may be included intermediate to the counterflow tube regulator R3 27 and counterflow tube 8. When in its default closed position, the 3-2-way solenoid valve 28 allows for independent control of the counterflow tube 8.
[0084] A 5/2-way solenoid valve V4 29 may be included to control the pressure output to the aerosol delivery respiratory support 9, which comprises a bidirectional valve assembly 130. Two pneumatic lines 31 extend between the 5/2-way solenoid valve 29 and a pneumatic actuator 43 located at the bidirectional valve assembly 130. Pressure regulated by the system pressure regulator 21 may be switched between the two pneumatic lines 31 in order to open and close the aerosol delivery channel port 136 of the bidirectional valve assembly 130, thereby controlling whether the aerosol output to the patient is allowed or arrested.
[0085] FIGS. 3-5 show various views of the liquid dispenser 6, which supplies liquid drug to the nozzle 7. A liquid vial 23 is screwed into the dispenser cap 41, and then is slid into the dispenser mount 42. In a preferred embodiment, the liquid vial 23 may contain standard liquid volumes such as 15 mL or 50 mL, but the volume of the vial 23 may be any volume suitable for a given dosage or usage. The vial 23 may include half turn threads 45 configured to mate with cut threads 44 on the dispenser cap 41. This configuration promotes easy loading by achieving coupling with only a half twist of the vial 23.
[0086] The dispenser mount 42 may include a front recess through which the dispenser cap 41 is inserted, a back wall opposite the front recess, a top surface, and two side walls. The back wall of the dispenser mount 42 may include two threaded holes 46 for mounting the dispenser assembly onto the console 1. The liquid vial 23 is pressurized through a threaded port 47 located between the two threaded holes 46 on the back wall of the dispenser mount 42. The threaded port 47 extends to a perpendicular hollow channel 48 inside the dispenser mount 42 that directs the compressed gas downwards into the vial 23 (FIG. 5B). As shown in FIGS. 5B and 5D, a through channel 56 is included on the top surface of the dispenser mount 42. The through channel 56 includes threads for connecting the nozzle 7 to the dispenser mount 42 via a male luer lock fitting and a capillary. The dispenser cap 41 may include a locking mechanism comprising two cantilever clips 50 with slots 51 configured to interface with corresponding keys 52 located on sliding tracks 53 in the interior side walls of the dispenser mount 42. Each of the cantilevers 50 may include a ramped section such that the cantilevers 50 must be pinched to fit onto the sliding tracks 53 when inserting the dispenser cap 41 into the dispenser mount 42. When the dispenser cap 41 is fully inserted into the dispenser mount 42, the keys 52 on the dispenser mount 42 fall into the slots 51 of cantilevers 50, thereby creating a secure connection between the dispenser cap 41 and dispenser mount 42. Two O-rings 57 may be included in the liquid delivery port 58 to create an air and fluid tight seal when the dispenser cap 41 is slid into the dispenser mount 42. Additionally, the sliding tracks 53 on the dispenser mount 42 may be configured such that the O-rings 57 are compressed when the dispenser cap 41 is inserted into the dispenser mount 42. A capillary section and an inline check valve may be threaded to the liquid delivery port 58 on the dispenser cap 41.
[0087] FIG. 6 shows the structural components of the nozzle 7, which may include a knob 65, barrel 66, liquid jet nozzle tip 67 and nozzle cap 68 (FIG. 6A). Nozzle 7 includes a nozzle liquid input 60, a nozzle gas input, and an aerosol exit orifice 15. The liquid is fed from the liquid vial 23 to the nozzle liquid input 60 via a liquid supply line 11, which may for instance be a capillary. In a preferred embodiment, the knob 65 may include threads 69 to allow a capillary to be connected to the nozzle 7 via a male luer connector. The liquid may then be fed through a liquid microchannel 70 running axially through the lengthwise axis of the nozzle barrel 66 between the nozzle liquid input 60 and the fluid exit 75, as shown in section view C-C FIG. 6C. Gas flows to the nozzle gas input via a gas supply line 12, and is fed to a plurality of air microchannels 71, which may be disposed coaxial to the liquid microchannel 70. In a preferred embodiment, four air microchannels 71 are included inside the nozzle 7. Each air microchannel 71 may have a corresponding hole 72 in the nozzle barrel 66 through which the gas may flow in. The gas exit 74 of the air microchannels 71 and fluid exit 75 of the liquid microchannel 70 converge at the aerosolization space 73 where the aerosolization occurs. The aerosolizing space 73 is defined between the outlet of the liquid jet nozzle tip 67 and the nozzle cap 68 (FIG. 6D). The aerosols generated in the aerosolization space 73 are expelled through the aerosol exit orifice 15 into the aerosol chamber 10.
[0088] FIG. 7 shows an assembly including a chamber, cone, concentrator, and bidirectional valve. This assembly comprises a nozzle 7, a pedestal 87, an aerosol chamber 10, a cone 89, a concentrator 105, and a bidirectional valve assembly 130. The aerosol chamber 10 comprises an aerosol chamber input end 79 and an aerosol chamber output end 80. The aerosol chamber 10 houses the nozzle 7 and the counterflow tube 8. The nozzle 7 is inserted from the backside of the chamber 10. In a preferred embodiment, the chamber 10 may additionally include a cone 89 having a cone input end 93 having larger diameter and a cone output end 94 having a smaller diameter. The cone input end 93 may connect with the aerosol chamber output end 80, and the cone output end 94 may connect with the concentrator input end 117. In this configuration, the aerosol chamber 10 is effectively extended such that the aerosol chamber output end 80 and cone output end 94 are one and the same. In another embodiment, the chamber 10 and concentrator 105 may be configured to allow the aerosol chamber output end 80 to directly connect to the concentrator input end 117. The aerosol chamber 10 may include three annuli surrounding the nozzle barrel 66, specifically a first O-ring annulus 81, an air annulus 82, and a second O-ring annulus 83. The air annulus 82 supplies air to the air microchannels 71 in the nozzle barrel 66. The first and second O-ring annuli 81, 83 are disposed on opposite sides of the air annulus 82, and house O-rings.
[0089] In one configuration (as shown in FIG. 7C), a female pneumatic quick connect is threaded on the back of the chamber 10 for supplying air to the nozzle 7 and the counterflow tube 8 through a common port 84. The access hole 85 for the air annulus 82 for nozzle 7 may be plugged using a grub screw. In an alternate configuration (as shown in FIG. 2), the counterflow tube 8 and the nozzle 7 may have independent sources of compressed air supply, and accordingly include separate ports. The compressed air may be supplied using respective male quick connect pneumatic connectors for the nozzle 7 and the counterflow tube 8. The access hole 85 for the air annulus 82 may be plugged using a grub screw. The chamber 10 may further comprise two or more ribs 86 configured to mount the chamber 10 onto a pedestal 87. The pedestal 87 may include matching slots 88 configured to interface with the ribs 86. The structure of the pedestal 87 and its slots 88 are structured to enable the chamber 10 to firmly click onto the pedestal 87 for easy mounting and dismounting. For focusing the generated aerosol, a cone 89 may optionally be attached to the aerosol chamber output end 80 via a lip seal 90. The chamber 10 may further include a small drain hole 91 located at the bottom of the chamber 10 for draining liquid deposited on the inside walls of the chamber 10 and/or cone 89. Liquid draining through the small drain hole 91 may be deposited into an inbuilt reservoir 92 located in the pedestal 87. The gas flow from the counterflow tube 8 opposes and reduces aerosol velocity emanating from the nozzle 7, thereby creating a virtual baffle. Disposed downstream from the aerosol chamber 10 is concentrator 105 including an input tube 109, an output tube 110, and an exhaust port 111. Downstream of the concentrator 105 is the bidirectional valve assembly 130 including the bidirectional valve assembly input 131, bidirectional valve assembly output 139, aspiration port 137 which is shown in FIG. 7C in a closed configuration blocked by cylindrical disc 132.
[0090] FIG. 8 shows a concentrator have a cross-slit, in the following named a cross concentrator 105 shown in FIG. 8A, which comprises an input housing part 106 and an output housing part 107. The input housing part 106 comprises a patterned mold 108 configured to connect with an input tube 109. Similarly, the output housing part 107 is configured to connect with an output tube 110. The input tube 109 may include an input tube entrance port 119, for instance having a circular cross-section as in the shown embodiment, but could alternatively square, polygonal, oval or of any other suitable shape, and an input tube exit port 120 having the shape of a cross-slit, wherein the cross-sectional shape of the input tube 109 transitions from said non-cross-slit-shape at the input tube entrance port 119 to a cross-slit-shape at the input tube exit port 120. The cross-slit shape preferably includes two linear slots crossing each other at a 90 angle, but alternative any other angle is possible. Also, the crossing slits do not necessarily need to be linear, although this is a preferred shape from both a manufacturing standpoint as well as an alignment standpoint with a corresponding output tube cross-slit. The output tube 110 may include an output tube entrance port 121 and an output tube exit port 122, wherein the cross-sectional shape of the output tube 110 transitions between the output tube entrance port 121 and an output tube exit port 122. The output tube entrance port may have a cross-slit-shape corresponding to the cross-slit of the input tube, and may be aligned therewith. As shown in FIG. 8D, the input tube 109 may converge from the input tube entrance port 119 to the input tube exit port 120, such that the input tube entrance port 119 has a greater cross-sectional area than that of the input tube exit port 120. Conversely, the output tube 110 may diverge from the output tube entrance port 121 to the output tube exit port 122, such that the output tube entrance port 121 has a lesser cross-sectional area than that of the output tube exit port 122. The input tube exit port 120 and output tube entrance port 121 may be disposed along a joint longitudinal axis and spaced apart by a gap 123.
[0091] Diverging of the input tube is optional but may be preferred for increasing the aerosol velocity through the cross-slit and therefore the momentum of the aerosol particles, resulting in a higher particle concentration rate. Converging of the output tube is likewise optional but preferred for reducing the velocity of the aerosol flow for a smoother for inhalation action and distribution of the aerosol particles. In lieu of converging/diverging profiles within the input/output tubes, a similar effect could also be accomplished by including additional components with similar profiles connected upstream/downstream of the input/output tubes. In this context, converging is to be understood as reducing the total cross-section of the lumen in the input tube along the direction of aerosol flow, while diverging is to be understood as increasing the total cross-section of the lumen in the output tube along with the direction of flow.
[0092] FIG. 8B shows the exploded view of the concentrator assembly. The output housing part 107 may include an exhaust port 111 for venting dilution gas. The housing 106, 107 may share a joint longitudinal axis with the input tube 109 and the output tube 110. This longitudinal axis is also the axis of the aerosol flow and runs through the center of the cross-slit, which is the point of intersection of the linear slits. The plenum 124 may be substantially encompassed by either the input housing part 106 or the output housing part 107. The housing part not encompassing the plenum 124 may be essentially disc-shaped, whereas the housing part substantially encompassing the plenum 124 may also include the exhaust tube 111 extending essentially radially in a transverse direction with respect to said longitudinal axis. The input tube 109 and output tube 110 may have radial sizes transverse to the longitudinal axis that are less than a third of a radial size of the plenum 124 transverse to said longitudinal axis. The exhaust port 111 may be oriented perpendicular to the longitudinal axis of aerosol flow between the concentrator input end 117 and concentrator output end 118, as also defined by the cross-section E-E shown in FIG. 8C. A pressure relief valve may be connected to the exhaust tube 111 for keeping a constant pressure within and across the concentrator 105, including at the output tube exit port 122. Both the input housing part 106 and the output housing part 107 may include lobes 112 and corresponding lobe molds 113 for alignment. The input housing part 106 and the output housing part 107 may be connected via a lip seal 114. The housing 106, 107 may encompass a plenum 124 defined by a void space surrounding and encompassing the input tube 109 and output tube 110, preferably in the shape of an annulus but alternatively could be any other shape that creates sufficient space around the gap 123 for receiving the exhaust aerosol of low particle concentration without significant pressure drop, such that the overall pressure drop through the concentrator, and therefore for the entire system, is kept low. The plenum 124 may be connected to the exhaust port 111. The concentrator assembly may include a concentrator input mating surface 115 and a concentrator output mating surface 116 (shown in FIG. 8D) respectively corresponding to the concentrator input end 117 and the concentrator output end 118 through which the respirable aerosol flows. The concentrator input mating surface 115 may be configured to facilitate easy attachment with the cone 89 without necessitating fasteners.
[0093] FIG. 9 shows an Aerosol delivery respiratory support assembly comprising the bidirectional valve assembly 130 shown in FIG. 9A enables functionality of the aerosol delivery respirator support 9. In one embodiment, the bidirectional valve assembly input 131 may connect with the cone output end 94 of the cone 89. In another embodiment the system includes a concentrator 105, the bidirectional valve assembly input 131 may connect with the concentrator output end 118 of the concentrator 105. A cylindrical disc 132 is included inside the bidirectional valve assembly 130. A pivot pin 133 is inserted through a hole in a sidewall of the bidirectional valve assembly 130 and connects to the disc 132 by interfacing with a set screw 134 located on the disc 132. These elements and their interactions are shown in an exploded view in FIG. 9B. As seen in FIG. 9D, the bidirectional valve assembly 130 includes an annular aerosol delivery channel port 136 extending between a bidirectional valve assembly input 131 and a bidirectional valve assembly output 139. The upper wall of the aerosol delivery channel port 136 includes a first seat 135 against which the disc 132 butts up against when in a vertical position, thereby inhibiting further counterclockwise rotation. The lower wall includes a second seat 138 offset a distance from the pin 133 such that the disc 132 is simply supported when in a horizontal position, as shown in FIG. 9D. The pin 133 may be actuated using a reciprocating pneumatic actuator 43 driven by the 5/2-way solenoid valve 29. When actuated by the pneumatic actuator 43, the pin 133 may rotate the disc 132 90 degrees to switch between open and closed positions. FIG. 9D shows the bidirectional valve assembly in an open position, wherein the disk 132 seats horizontally within the second seat 138 such that the aerosol delivery channel port 136 is open and the aspiration port 137 is closed. In a closed position, the disc 132 seats vertically within the first seat 135 such that the aerosol delivery channel port 136 is blocked and the aspiration port 137 is opened. In one embodiment of the invention, the bidirectional valve assembly output 139 may be configured to attach to an endotracheal tube (not pictured) for remote aerosol delivery.
[0094] FIGS. 10-14 demonstrate some results achieved by the system according to the invention with respect to the particle size distribution over the liquid flow rate of the liquid to be aerosolized, showing graphs for viscosities of 4 cP, 11 cP and 21 cP for the aerosolized liquid for a variety of nozzles of different nozzle exit orifice diameters, aerosolizing gases and system pressures.
[0095] FIG. 10 shows plots of flow rate (ranging from 0.75 ml/min to 3.5 ml/min) versus particle size (Dv 50 in units of m) for three different concentrations of aqueous polyvinylpyrrolidone (PVP) with a system using compressed air, a system pressure of 60 psi, and a nozzle exit orifice diameter of 500 m. The three different concentrations (by weight) of aqueous PVP solutions were 8%, 14% and 19%, and resulted in respective solution viscosities of 4, 11 and 21 cP. The 8% concentration solution is denoted by square plot points with a solid trendline, the 14% concentration solution is denoted by circular plot points with a dashed trendline, and the 19% concentration solution is denoted by triangular plot points with a dotted trendline. When the PVP solutions were aerosolized by AeroPulsR system at liquid pressure of 60 psi, the particle sizes of aerosols were found to be related to (i) PVP concentrations, (ii) the flow rates of the liquids, and (iii) the type of compressed gas used. From the flow rate ranging from 0.75 ml/min to 3.5 ml/min for each solution, the majority of the Dv 50 values of the aerosols were under 5 m, except in one test where 8% PVP solution was aerosolized at 3.5 ml/min and compressed air was used. Meanwhile, smaller aerosols were obtained from a solution with higher PVP concentrations at the same flow rate.
[0096] FIG. 11 shows a plot for the same parameters as in FIG. 10, except substituting compressed heliox (a mixture of 80% helium and 20% oxygen) for compressed air to investigate the effect of compressed heliox on the particle size. Accordingly, aerosolization is conducted with identical settings mentioned previously with compressed air. A notable decrease in the particle sizes is observed with compressed heliox, when compared with compressed air.
[0097] FIG. 12 shows a plot for substantially the same parameters as in FIG. 10, except at a reduced system pressure of 50 psi. For obtaining this plot, the liquid pressure was reduced to 49 psi from 60 psi, and the aerosols were measured at a flow rate ranging from of 1 to 3 ml/min for PVP aqueous solution concentration (by weight) of 8%, 14%, and 19%. It was found that the overall aerosol size trend for different PVP solution concentration was similar to that observed for 60 psi liquid pressure. However, particle sizes for individual PVP concentrations were higher when compared with higher gas pressure.
[0098] FIG. 13 shows a plot for substantially the same parameters as in FIG. 10, except substituting the 500 m nozzle with a 700 m nozzle to investigate the size of the nozzle's exit orifice on aerosol particle size. With a system pressure of 60 psi, PVP aqueous solutions with concentrations of 8%, 14%, and 19% were aerosolized with a flow rate ranging from 1.5 to 4.5 ml/min. When compared with aerosol sizes achieved from 500 m nozzle at 60 psi, it was found that under the same pressure and flow rate conditions, smaller aerosols from the same PVP solution can be generated from the 700 m nozzle. The size of the nozzle exit orifice, therefore, can be modified to affect the size of the aerosol. For instance, at a flow rate of 3 ml/min, 21 cP PVP solution, and 500 m nozzle exit orifice diameter, a Dv 50 of 4.2 m resulted. However, using the same PVP solution with a nozzle exit orifice diameter of 700 m resulted in a Dv 50 of 2.7 m.
[0099] FIG. 14 shows a three-axis plot of flow rate (ranging from 0.75 ml/min to 3.5 ml/min) versus particle size (Dv 50 in m) and span of H2O aerosol versus particle size (Dv 50 in m) for H2O/compressed air and H2O/heliox. The particle size for the H2O/compressed air combination is denoted by hollow square plot points with a dashed trendline. The particle size for the H2O/heliox combination is denoted by hollow triangular plot points with a dotted trendline. The span for the H2O/compressed air combination is denoted by solid square plot points with a dot-dashed trendline. The span for the H2O/heliox combination is denoted by solid triangular plot points with a solid trendline. The AeroPulsR system generates aerosol particles with a narrow distribution. A narrow span in the range of 1.5 to 2 is observed for both compressed air and heliox.
[0100] In the following, additional embodiments of the invention are described:
[0101] Embodiment 1. An aerosol concentrator 105 dividing an input aerosol of an input particle concentration into a concentrated respirable aerosol of an increased particle concentration that is higher than the input particle concentration and an exhaust aerosol of a lower particle concentration that is lower than the input particle concentration, said concentrator 105 comprising: [0102] an input tube 109 having a lumen and comprising: [0103] an input tube entrance port 119 having an input tube entrance port cross-sectional shape differing from a cross-slit shape; [0104] an input tube exit port 120 having a cross-slit shape, wherein the input tube entrance port cross-sectional shape transitions between the input tube entrance port and the input tube exit port 119 to the cross-slit-shaped exit port 120 cross-sectional shape; [0105] an output tube 110 having a lumen and comprising: [0106] an output tube entrance port 121 having a cross-slit-shaped cross-section, said output tube entrance port 121 being aligned with and spaced apart from the input tube exit port 120 by a gap 123 between the input tube exit port 120 and the output tube entrance port 121; and [0107] an output tube exit port 122 wherein the output tube entrance port cross-sectional shape transitions between the output tube entrance port 121 and the output tube exit port 122 to an output tube exit port cross-sectional shape; and [0108] a housing 106, 107 encompassing a plenum 124, said plenum 124 encompassing the gap 123 between the input tube 109 and the output tube 110, wherein the plenum 124 is connected to an exhaust port 111 through which an exhaust aerosol exits the plenum 124.
[0109] Embodiment 2. The aerosol concentrator 105 according to embodiment 1, wherein the input tube 109 converges from its input tube entrance port 119 to its input tube exit port 120 from an input tube entrance port cross-sectional area that is larger than an input tube exit port cross-sectional area.
[0110] Embodiment 3. The aerosol concentrator 105 according to embodiments 1 or 2, wherein the output tube 110 diverges from its output tube entrance port 121 to its output tube exit port 122 from an output tube entrance port cross-sectional area that is smaller than an output tube exit port cross-sectional area.
[0111] Embodiment 4. The aerosol concentrator 105 according to one of embodiments 1-3, wherein the input tube 109 and the output tube 110 have a joint longitudinal axis and have radial sizes transverse to the longitudinal axis that are less than a third of a radial size of the plenum 124 transverse to said longitudinal axis.
[0112] Embodiment 5. The aerosol concentrator 105 according to one of the embodiments 1-4, wherein the housing 106, 107 compromises an input housing part 106 holding the input tube 109, and output housing part 107 holding the output tube 110 and an exhaust tube 111, and a seal 114 is provided between the input housing part 106 and the output housing part 107.
[0113] Embodiment 6. The aerosol concentrator 105 according to embodiments 4 or 5, wherein the housing 106, 107 shares the same joint longitudinal axis with the input tube 109 and the output tube 110 and the plenum 124 is encompassed at least for the most part by either one of the input housing part 106 or the output housing part 107, while the other part of the output 107 or input housing 106, respectively, is essentially disc-shaped, with the housing part encompassing at least for the most part the plenum 124 also having the exhaust tube 111 which extends essentially radially in a transverse direction with respect to said longitudinal axis.
[0114] Embodiment 7. The aerosol concentrator 105 according to embodiments 5 or 6, wherein a pressure relief valve is connected to the exhaust tube 111 keeping the pressure within and across concentrator 105 and consequently at the output tube exit port 122 essentially constant.
[0115] Embodiment 8. The aerosol concentrator 105 according to one of embodiments 1-7 wherein the concentrator 105 is designed to concentrate an input aerosol having fine particles of a particle size distribution of 1-6 m MMAD suspended in gas.
[0116] Embodiment 9. The aerosol concentrator 105 according to one of embodiments 1-8 wherein the concentrator 105 is designed to concentrate an aerosol using virtual impaction at a small positive pressure within and across concentrator 105 all the way to the output tube exit port 122 such that the concentrated respirable aerosol can be delivered to the patient at the small positive pressure without the use of pumps to remove the exhausted gas.
[0117] The following is a list of reference numerals as shown in the drawings: [0118] console 1 [0119] patient/clinician interface 2 [0120] microcontroller 3 [0121] hardware controller 4 [0122] internal hardware 5 [0123] liquid dispenser 6 [0124] aerosol nozzle 7 [0125] counter flow tube 8 [0126] aerosol delivery respiratory support 9 [0127] aerosol chamber 10 [0128] liquid supply line 11 [0129] gas supply line 12 [0130] gas supply line 13 [0131] counterflow gas tube supply line 14 [0132] aerosol exit orifice 15 [0133] counterflow gas tube exit opening 16 [0134] high pressure source 20 [0135] system pressure regulator 21 [0136] liquid pressure regulator 22 [0137] liquid vial 23 [0138] 3-2 way solenoid valve V1 24 [0139] nozzle gas regulator 25 [0140] three-way solenoid valve V2 26 [0141] regulator R3 27 [0142] 3-2-way solenoid valve V3 28 [0143] 5-2-way solenoid valve V4 29 [0144] two pneumatic lines 31 [0145] dispenser cap 41 [0146] dispenser mount 42 [0147] pneumatic actuator 43 [0148] cut threads 44 [0149] half turn threads 45 [0150] threaded holes 46 [0151] threaded port 47 [0152] hollow channel 48 [0153] cantilever clips 50 [0154] slots 51 [0155] keys 52 [0156] sliding tracks 53 [0157] through channel 56 [0158] O-rings 57 [0159] liquid delivery port 58 [0160] nozzle liquid input 60 [0161] knob 65 [0162] barrel 66 [0163] liquid jet nozzle tip 67 [0164] nozzle cap 68 [0165] threads 69 [0166] liquid microchannel 70 [0167] air microchannels 71 [0168] hole 72 [0169] aerosolization space 73 [0170] gas exit 74 [0171] fluid exit 75 [0172] aerosol chamber input end 79 [0173] aerosol chamber output end 80 [0174] first O-ring annulus 81 [0175] air annulus 82 [0176] second O-ring annulus 83 [0177] common port 84 [0178] access port 85 [0179] ribs 86 [0180] pedestal 87 [0181] matching slots 88 [0182] cone 89 [0183] lip seal 90 [0184] small drain hole 91 [0185] inbuilt reservoir 92 [0186] cone input end 93 [0187] cone output end 94 [0188] cross concentrator 105 [0189] input housing part 106 [0190] output housing part 107 [0191] patterned mold 108 [0192] input tube 109 [0193] output tube 110 [0194] exhaust port 111 [0195] lobes 112 [0196] lobe molds 113 [0197] lip seal 114 [0198] concentrator input mating surface 115 [0199] concentrator output mating surface 116 [0200] concentrator input end 117 [0201] concentrator output end 118 [0202] input tube entrance port 119 [0203] input tube exit port 120 [0204] output tube entrance port 121 [0205] output tube exit port 122 [0206] gap 123 [0207] plenum 124 [0208] Bidirectional valve assembly 130 [0209] bidirectional valve assembly input 131 [0210] cylindrical disc 132 [0211] pivot pin 133 [0212] set screw 134 [0213] first seat 135 [0214] aerosol delivery channel port 136 [0215] aspiration port 137 [0216] second seat 138 [0217] bidirectional valve assembly output 139
