US20100282766A1 - Low-Dead Volume Microfluidic Component and Method - Google Patents
Low-Dead Volume Microfluidic Component and Method Download PDFInfo
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- US20100282766A1 US20100282766A1 US12/436,360 US43636009A US2010282766A1 US 20100282766 A1 US20100282766 A1 US 20100282766A1 US 43636009 A US43636009 A US 43636009A US 2010282766 A1 US2010282766 A1 US 2010282766A1
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- dead volume
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- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61M—DEVICES FOR INTRODUCING MEDIA INTO, OR ONTO, THE BODY; DEVICES FOR TRANSDUCING BODY MEDIA OR FOR TAKING MEDIA FROM THE BODY; DEVICES FOR PRODUCING OR ENDING SLEEP OR STUPOR
- A61M5/00—Devices for bringing media into the body in a subcutaneous, intra-vascular or intramuscular way; Accessories therefor, e.g. filling or cleaning devices, arm-rests
- A61M5/14—Infusion devices, e.g. infusing by gravity; Blood infusion; Accessories therefor
- A61M5/142—Pressure infusion, e.g. using pumps
- A61M5/145—Pressure infusion, e.g. using pumps using pressurised reservoirs, e.g. pressurised by means of pistons
- A61M5/148—Pressure infusion, e.g. using pumps using pressurised reservoirs, e.g. pressurised by means of pistons flexible, e.g. independent bags
- A61M5/152—Pressure infusion, e.g. using pumps using pressurised reservoirs, e.g. pressurised by means of pistons flexible, e.g. independent bags pressurised by contraction of elastic reservoirs
-
- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61M—DEVICES FOR INTRODUCING MEDIA INTO, OR ONTO, THE BODY; DEVICES FOR TRANSDUCING BODY MEDIA OR FOR TAKING MEDIA FROM THE BODY; DEVICES FOR PRODUCING OR ENDING SLEEP OR STUPOR
- A61M5/00—Devices for bringing media into the body in a subcutaneous, intra-vascular or intramuscular way; Accessories therefor, e.g. filling or cleaning devices, arm-rests
- A61M5/14—Infusion devices, e.g. infusing by gravity; Blood infusion; Accessories therefor
- A61M5/142—Pressure infusion, e.g. using pumps
- A61M5/14244—Pressure infusion, e.g. using pumps adapted to be carried by the patient, e.g. portable on the body
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
- F04B—POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS
- F04B19/00—Machines or pumps having pertinent characteristics not provided for in, or of interest apart from, groups F04B1/00 - F04B17/00
- F04B19/006—Micropumps
-
- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61M—DEVICES FOR INTRODUCING MEDIA INTO, OR ONTO, THE BODY; DEVICES FOR TRANSDUCING BODY MEDIA OR FOR TAKING MEDIA FROM THE BODY; DEVICES FOR PRODUCING OR ENDING SLEEP OR STUPOR
- A61M5/00—Devices for bringing media into the body in a subcutaneous, intra-vascular or intramuscular way; Accessories therefor, e.g. filling or cleaning devices, arm-rests
- A61M5/14—Infusion devices, e.g. infusing by gravity; Blood infusion; Accessories therefor
- A61M2005/1401—Functional features
- A61M2005/1405—Patient controlled analgesia [PCA]
-
- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61M—DEVICES FOR INTRODUCING MEDIA INTO, OR ONTO, THE BODY; DEVICES FOR TRANSDUCING BODY MEDIA OR FOR TAKING MEDIA FROM THE BODY; DEVICES FOR PRODUCING OR ENDING SLEEP OR STUPOR
- A61M5/00—Devices for bringing media into the body in a subcutaneous, intra-vascular or intramuscular way; Accessories therefor, e.g. filling or cleaning devices, arm-rests
- A61M5/14—Infusion devices, e.g. infusing by gravity; Blood infusion; Accessories therefor
- A61M5/142—Pressure infusion, e.g. using pumps
- A61M5/14244—Pressure infusion, e.g. using pumps adapted to be carried by the patient, e.g. portable on the body
- A61M5/14248—Pressure infusion, e.g. using pumps adapted to be carried by the patient, e.g. portable on the body of the skin patch type
- A61M2005/14252—Pressure infusion, e.g. using pumps adapted to be carried by the patient, e.g. portable on the body of the skin patch type with needle insertion means
-
- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61M—DEVICES FOR INTRODUCING MEDIA INTO, OR ONTO, THE BODY; DEVICES FOR TRANSDUCING BODY MEDIA OR FOR TAKING MEDIA FROM THE BODY; DEVICES FOR PRODUCING OR ENDING SLEEP OR STUPOR
- A61M2206/00—Characteristics of a physical parameter; associated device therefor
- A61M2206/10—Flow characteristics
- A61M2206/20—Flow characteristics having means for promoting or enhancing the flow, actively or passively
-
- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61M—DEVICES FOR INTRODUCING MEDIA INTO, OR ONTO, THE BODY; DEVICES FOR TRANSDUCING BODY MEDIA OR FOR TAKING MEDIA FROM THE BODY; DEVICES FOR PRODUCING OR ENDING SLEEP OR STUPOR
- A61M5/00—Devices for bringing media into the body in a subcutaneous, intra-vascular or intramuscular way; Accessories therefor, e.g. filling or cleaning devices, arm-rests
- A61M5/14—Infusion devices, e.g. infusing by gravity; Blood infusion; Accessories therefor
- A61M5/141—Infusion devices, e.g. infusing by gravity; Blood infusion; Accessories therefor with capillaries for restricting fluid flow
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
- Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
- Y10T137/00—Fluid handling
- Y10T137/0318—Processes
Definitions
- This invention relates generally to a system and method of reducing dead volume in a microfluidic circuit and, more specifically, to a system and method of reducing the dead volume in a component utilized within microfluidic circuits.
- Microfluidic circuits are utilized in various personal medical devices (e.g., insulin infusion devices) to control delivery of medications or other fluids.
- the volumetric flow rates within these circuits are very low, due to low dosing schedules, and to allow for accurate control of the medication being delivered.
- the low flow rates can prevent the circuit from being quickly filled prior to utilizing the device, which can pose a significant inconvenience to the user. Additionally, any excess volume within the circuit results in medication that remains undelivered once a pressure source for the medication is terminated.
- Lengthy fill times and undelivered medication are related to total volume within a microfluidic system.
- Each component e.g., reservoirs or other chambers, valves, conduits or channels, pressure sensors, flow restrictors, etc.
- This capacity is defined, in part, by the internal dimensions, function, and configuration of the component, including moving components within the flowpath. Manufacturing methods and tolerances may affect the capacity, as well. While a particular component may only require a relatively small portion of the total internal volume to perform its function (this volume may be referred to as the “working volume”), access required for manufacturing the component may prevent minimizing the total volume. This excess volume (or “dead volume”) over that of the working volume increases the total volume of the flow component and, subsequently, of the fluidic circuit of the delivery system.
- the invention relates to a method for reducing a dead volume of a microfluidic circuit having a reservoir, an outlet, and a microfluidic flowpath fluidly connecting the reservoir and the outlet, the method including providing a variable-volume fluid chamber located between the reservoir and the outlet for performing a function and in fluidic communication with the microfluidic flowpath.
- the variable-volume fluid chamber includes a total volume having a working volume and a dead volume, wherein the working volume is a volume necessary for the variable-volume fluid chamber to perform the function and the dead volume is a volume unnecessary for the variable-volume fluid chamber to perform the function.
- the method includes configuring the variable-volume fluid chamber to reduce the dead volume, such that the working volume is substantially the same as the total volume. In an embodiment, the configuring step results in the total volume being substantially the same as the working volume.
- variable-volume fluid chamber includes a base surface, an inlet, and a separate outlet.
- the configuring step includes providing a flexible membrane, wherein the base surface and the membrane define a first volume when the membrane is proximate the base surface, and the base surface and the membrane define a second volume when the membrane is displaced by a fluid pressure away from the base surface.
- the membrane can be biased towards the base surface.
- the invention relates to a low-dead volume variable-volume fluid chamber manufactured in accordance with the method of the above embodiment. In an embodiment of the above aspect, the working volume is about 5% of the total volume.
- FIG. 1 is a schematic diagram and related time/volume tables of an exemplary infusion device microfluidic circuit
- FIG. 2 is a schematic diagram of another exemplary infusion device microfluidic circuit in accordance with one embodiment of the invention.
- FIG. 3 is a schematic diagram of a theoretical microfluidic circuit flow component
- FIGS. 4A and 4B are schematic sectional views of an exemplary variable-volume chamber and a low-dead volume version of the same variable-volume chamber in accordance with one embodiment of the invention.
- a microfluidic circuit 10 for delivering a fluid medication to a patient, as depicted in FIG. 1 .
- the fluid delivery or flow components of this circuit 10 include, in series, an elastomer reservoir or bladder 12 , a first channel 14 , a flow component 16 , a second channel 18 , and an outlet 20 .
- the flow component 16 may function, e.g., as a storage chamber for doses of medicament to be delivered on an infrequent basis to a human user or patient 24 .
- the reservoir 12 is filled with medication via a one-way inlet valve 22 .
- the microfluidic circuit 10 is utilized in an insulin infusion delivery device used to deliver insulin to the patient 24 via a subcutaneous cannula in fluidic communication with the outlet 20 .
- the lower table included in FIG. 1 depicts information relevant to a low-dead volume version of the microfluidic circuit 10 .
- the upper table depicts information relevant to a baseline version of the microfluidic circuit 10 upon which no volume reduction modifications have been made.
- the total volume of each flow component is depicted in FIG. 1 in Row A of both the upper and lower tables.
- the elastomer reservoir 12 supplies the downstream microfluidic circuit flow components with insulin until the elastomer no longer exerts sufficient pressure to overcome the flow resistance in the circuit 10 . At that point, in this example, 87.39 ⁇ l of insulin remains in the reservoir 12 . See Row D.
- Row B in both the upper and lower tables depicts the flow rate Q through the various components.
- the flow rate Q is defined, at least in part, by flow restrictors and other components present within the circuit.
- Row C in both the upper and lower tables depicts the amount of time required for insulin to completely fill each dry flow component once flow from the reservoir 12 is initiated, as the sum of which is the total start-up time for the entire microfluidic circuit 10 to fill.
- This total start-up time reflects the time required to deliver a first dose of insulin to the user 24 .
- the difference in volume between a standard flow component 16 (21.22 ⁇ l) and a low-dead volume flow component 16 (8.34 ⁇ l) contributes directly to the significant reduction in total start-up time of the circuit 10 .
- the fill time for the standard flow component 16 is over twice that of the low-dead volume fill time, while the total fill time of the standard circuit is over 1 hour and 15 minutes greater than the microfluidic circuit using a low-dead volume component. This significant delay inherent in the baseline version of the circuit 10 is both an inconvenience and could be a risk to the user's health.
- Row D in both the upper and lower tables depicts the amount of insulin that is effectively trapped within the microfluidic circuit 10 once the elastomer reservoir 12 can no longer induce flow at the outlet 20 . Note that a significant portion of the trapped insulin, other than that remaining in the reservoir 12 , is contained within the flow component 16 . Accordingly, use of a low-dead volume flow component, for example, a variable-volume chamber, is advantageous to reduce the total amount of lost insulin within the microfluidic circuit 10 .
- FIG. 2 is a schematic diagram of an exemplary infusion device microfluidic circuit 100 that benefits from the low-dead volume technology described herein.
- Other infusion device microfluidic circuits benefit as well, such as those described, for example, in U.S. Patent Application Publication No. 2005/0165384 A1, published Jul. 28, 2005, the disclosure of which is hereby incorporated by reference herein in its entirety.
- Microfluidic circuits having other configurations or utilizing any number of other components also may benefit from inclusion of the low-dead volume variable-volume fluid chamber described herein.
- the microfluidic circuit 100 includes a reservoir 102 that is, in this case, comprised of an elastomer bladder.
- a fill port 104 is used to introduce insulin to the microfluidic circuit 100 .
- introducing insulin via the fill port 104 fills both the reservoir 102 and a variable-volume bolus reservoir 106 .
- Check valves 108 in the circuit 100 prevent backflow of insulin in a number of locations.
- a basal flowpath 112 delivers a constant dose of insulin to a user; the bolus flowpath 114 delivers a bolus dose of insulin to the user as needed or desired by the user, upon actuation of a bolus button 118 .
- the basal flowpath 112 includes a pressure sensor 116 or other flow sensor in communication with the flowpath 112 .
- the user presses the bolus button 118 that drives a single stroke (delivering a single dose) of a bolus displacement chamber 120 and opens two valves 122 .
- the valves 122 are in series providing failsafe redundancy for safety purposes.
- Flow restrictors 124 limit the rate of fluid flow through the flowpaths 112 , 114 .
- the parallel flowpaths 112 , 114 join at a common channel 126 , upstream of an internal chamber or a cannula void 128 .
- the cannula void 128 is formed in a cannula base 130 , that provides a fluidic connection to a cannula 132 .
- the cannula 132 extends below the skin 134 of the user, thus delivering the insulin subcutaneously.
- reducing the dead volume in the variable-volume bolus reservoir 106 decreases the dead volume throughout the entire microfluidic circuit 100 .
- FIG. 3 depicts a theoretical flow component 200 . While most flow components utilized in a microfluidic circuit serve specific purposes, each generally share several common elements, as depicted in FIG. 3 .
- the flow component includes a housing or some other inner physical boundary that is in contact with the fluid passing therethrough. In FIG. 3 , this inner physical boundary 202 is depicted as a hollow cube.
- the flow component includes an inlet, through which fluid flows into the component.
- the inlet 204 penetrates a wall of the physical boundary 202 defined by corners bearing the letter “A”; the dimensions of the inlet 204 are defined by a height h, and a width w, although the inlet 204 could be circular or any other shape.
- the flow component includes an outlet, through which fluid flows out of the component.
- the outlet 206 penetrates a wall of the physical boundary 202 defined by the corners bearing the letter “B”; the dimensions of the outlet 206 are defined by a height h, and a width w, in this case, matching the dimensions of the inlet 204 , although the outlet 206 could be any shape or size and disposed at any location along the boundary 202 .
- the inner physical boundary of a flow component defines three volumes: a total volume V, a working volume W, and a dead volume D.
- the total volume V is the volume bounded by the inner physical boundary; accordingly, in FIG. 3 , the total volume V is defined by the walls of the cube (i.e., the inner physical boundary 202 ).
- the working volume W is the minimum volume required to perform the function of the flow component, including connecting fluidicly the inlet and the outlet.
- the theoretical flow component 200 functions as a constant-volume chamber through which fluid passes (where the entire cube must be filled with fluid via the inlet 204 prior to any fluid exiting the cube via the outlet 206 ).
- the working volume W is the volume defined around a straight line 208 from a center C i of the inlet 204 to a center C o of the outlet 206 , the straight line having a length L.
- the actual volume of this working volume W may be defined, in part, by the total length of straight line L and the height h and width w of the inlet 204 and the outlet 206 , assuming the working volume has outer dimensions substantially similar to height h and width w. Therefore the working volume W may be defined approximately by equation (i) below.
- the dead volume D is the volume of the flow component 200 unnecessary to perform the function, and may be defined as the difference between the total volume V and the working volume W (in this case, the remainder of the volume contained within the inner physical boundary 202 , not including the working volume W), as shown in equation (ii) below.
- the dead volume-reduction example described herein may effectively configure the flow component to reduce the dead volume, such that the working volume is substantially the same as the total volume or as close to the total volume as reasonably achievable, under the circumstances.
- a number of factors may be considered.
- the function and operational performance of the flow component should not be affected adversely by the dead volume-reduction configuration change.
- the dead volume-reduction change should consider the potential impact on pressure losses associated with the flow component. Care should be taken when reducing dead volume of a flow component, to ensure the component can still be manufactured at acceptable cost.
- An example of the use of dead volume-reduction configuration change to reduce the dead volume of a flow component is described below.
- FIG. 4A is a schematic sectional view of a variable-volume chamber 500 .
- the chamber 500 is formed within a solid housing 502 and has a rigid base surface 504 , as well as an inlet 506 , and an outlet 508 .
- a rigid top surface 516 defines the upper surface of the chamber 500 .
- the entire volume of an internal chamber 500 a below a line 510 a must be filled before any fluid may pass out of the outlet 508 .
- FIG. 4B Depicted in FIG. 4B is a variable-volume chamber 500 ′ according to one embodiment of the present invention with reduced dead volume.
- membrane 510 ′ is biased or disposed against the rigid base 504 of the internal chamber 500 a ′ to define a first small volume approaching zero, as depicted here.
- the membrane 510 a ′ expands 512 ′.
- the pressure contained within expansion volume 514 ′ is immediately exerted against the membrane 510 a ′ and the fluid contained within the internal chamber 500 a ′.
- Pressure within the expansion volume 514 ′ may be relieved by a suitable vent, not shown. Due to the initial location of the membrane 510 a ′, once filling begins, pressure is essentially immediately exerted against the fluid, without requiring filling of an excessive dead volume of the internal chamber 500 a′.
- variable-volume chamber 500 depicted in FIG. 4A includes a total volume V of 230 ⁇ l. Of this amount, 218.5 ⁇ l was determined to be dead volume D and was subsequently reduced by membrane 510 a ′, leaving a working volume W of 11.5 ⁇ l. For this embodiment, then, reducing the dead volume D results in a working volume W that is about 5% of the total volume V for the variable-volume chamber 500 ′ of FIG. 6B , thus achieving a 95% reduction in the volume of the variable-volume chamber 500 . Other reductions are also contemplated.
- the basal circuit 112 includes a pressure sensor 116 and a cannula void 128 .
- the bolus circuit 114 includes a variable-volume chamber 106 and two valves 122 .
- the total volume of all conduits in the microcircuit 100 is about 7 ⁇ l, of which nearly none is dead volume.
- Other flow components in an exemplary microcircuit may include at least a cannula void 128 , valves 122 , and a pressure sensor 116 .
- a microcircuit 100 such as that depicted in FIG. 2
- the difference in volume of a standard microcircuit (having a baseline-volume fluid chamber) versus the volume of a low-dead volume circuit (having a low-dead volume variable-volume chamber) is depicted.
- TABLE 2 depicts other relevant properties of a low-dead volume variable-volume chamber, in an exemplary microcircuit, as that component is described in the Example.
- the total volume V and dead volume D of a standard flow component is provided.
- Other flow components in an exemplary microcircuit, as depicted in TABLE 2 may include at least a cannula void 128 , valves 122 , and a pressure sensor 116 .
- the cannula void 128 flow component is set aside separately, because its flow rate is different than the other flow components.
- Flow rates Q through each component are also provided.
- the flow rates Q are used to calculate the fill time for each component. Initially, the fill time for the exemplary fluid chamber is calculated before any dead-volume reduction structure is utilized. In that case, total volume V is divided by the flow rate Q to obtain the fill time for that component. Next, the fill time for the variable-volume chamber is calculated after the dead-volume reduction structure is utilized. In that case, working volume W is divided by the flow rate Q to obtain the fill time for the low-dead volume variable-volume chamber. It should be noted that the working volume is, as defined above, the minimum volume required to perform the function of the flow component.
- variable-volume chamber Since the function of the chamber is to hold liquid medicine, it has been assumed here for the purposes of illustration of the concept that a minimum of 11.5 ⁇ l is required for the functional working volume. Indeed, the working volume and dead volume of the variable-volume chamber may change as the chamber is made to hold different amounts of liquid medicine.
- the various materials utilized in the flow components described herein, as well as the microfluidic circuits in which those flow components are utilized may be metal, glass, and/or any type of polymer suitable for sterilization and useful for delivering insulin or other medicaments subcutaneously.
- Polyurethane, polypropylene, PVC, PVDC, EVA, and others are contemplated for use.
- medical-grade plastics may be utilized for the cannula itself, as well as other components that contact or otherwise penetrate the body of the patient. Needles made from medical-grade stainless steel are also desirable, to prevent failure associated with use. Accordingly, the components utilized to reduce the dead volume within the various components should be the same as, similar to, or at least compatible with the existing materials utilized.
Abstract
A method is described for reducing a dead volume of a microfluidic circuit that includes, in one embodiment, a reservoir, an outlet, and a microfluidic flowpath fluidly connecting the reservoir and the outlet. The method includes providing a variable-volume fluid chamber between the reservoir and the outlet for performing a function and in fluidic communication with the microfluidic flowpath, wherein the variable-volume fluid chamber includes a total volume including a working volume and a dead volume. The working volume is a volume necessary for the variable-volume fluid chamber to perform the function and the dead volume is a volume unnecessary for the variable-volume fluid chamber to perform the function. The method includes configuring the variable-volume fluid chamber to reduce the dead volume, such that the working volume of the component is substantially the same as the total volume.
Description
- This invention relates generally to a system and method of reducing dead volume in a microfluidic circuit and, more specifically, to a system and method of reducing the dead volume in a component utilized within microfluidic circuits.
- Microfluidic circuits are utilized in various personal medical devices (e.g., insulin infusion devices) to control delivery of medications or other fluids. In general, the volumetric flow rates within these circuits are very low, due to low dosing schedules, and to allow for accurate control of the medication being delivered. The low flow rates, however, can prevent the circuit from being quickly filled prior to utilizing the device, which can pose a significant inconvenience to the user. Additionally, any excess volume within the circuit results in medication that remains undelivered once a pressure source for the medication is terminated.
- Lengthy fill times and undelivered medication are related to total volume within a microfluidic system. Each component (e.g., reservoirs or other chambers, valves, conduits or channels, pressure sensors, flow restrictors, etc.) of a system has an internal capacity for a volume of fluid. This capacity is defined, in part, by the internal dimensions, function, and configuration of the component, including moving components within the flowpath. Manufacturing methods and tolerances may affect the capacity, as well. While a particular component may only require a relatively small portion of the total internal volume to perform its function (this volume may be referred to as the “working volume”), access required for manufacturing the component may prevent minimizing the total volume. This excess volume (or “dead volume”) over that of the working volume increases the total volume of the flow component and, subsequently, of the fluidic circuit of the delivery system.
- In one aspect, the invention relates to a method for reducing a dead volume of a microfluidic circuit having a reservoir, an outlet, and a microfluidic flowpath fluidly connecting the reservoir and the outlet, the method including providing a variable-volume fluid chamber located between the reservoir and the outlet for performing a function and in fluidic communication with the microfluidic flowpath. The variable-volume fluid chamber includes a total volume having a working volume and a dead volume, wherein the working volume is a volume necessary for the variable-volume fluid chamber to perform the function and the dead volume is a volume unnecessary for the variable-volume fluid chamber to perform the function. The method includes configuring the variable-volume fluid chamber to reduce the dead volume, such that the working volume is substantially the same as the total volume. In an embodiment, the configuring step results in the total volume being substantially the same as the working volume.
- In yet another embodiment, the variable-volume fluid chamber includes a base surface, an inlet, and a separate outlet. The configuring step includes providing a flexible membrane, wherein the base surface and the membrane define a first volume when the membrane is proximate the base surface, and the base surface and the membrane define a second volume when the membrane is displaced by a fluid pressure away from the base surface. The membrane can be biased towards the base surface. In another aspect, the invention relates to a low-dead volume variable-volume fluid chamber manufactured in accordance with the method of the above embodiment. In an embodiment of the above aspect, the working volume is about 5% of the total volume.
- Other features and advantages of the present invention, as well as the invention itself, can be more fully understood from the following description of the various embodiments, when read together with the accompanying drawings, in which:
-
FIG. 1 is a schematic diagram and related time/volume tables of an exemplary infusion device microfluidic circuit; -
FIG. 2 is a schematic diagram of another exemplary infusion device microfluidic circuit in accordance with one embodiment of the invention; -
FIG. 3 is a schematic diagram of a theoretical microfluidic circuit flow component; and -
FIGS. 4A and 4B are schematic sectional views of an exemplary variable-volume chamber and a low-dead volume version of the same variable-volume chamber in accordance with one embodiment of the invention. - Consider one embodiment of a
microfluidic circuit 10 for delivering a fluid medication to a patient, as depicted inFIG. 1 . The fluid delivery or flow components of thiscircuit 10 include, in series, an elastomer reservoir orbladder 12, afirst channel 14, aflow component 16, asecond channel 18, and anoutlet 20. Theflow component 16 may function, e.g., as a storage chamber for doses of medicament to be delivered on an infrequent basis to a human user orpatient 24. Thereservoir 12 is filled with medication via a one-way inlet valve 22. In this example, themicrofluidic circuit 10 is utilized in an insulin infusion delivery device used to deliver insulin to thepatient 24 via a subcutaneous cannula in fluidic communication with theoutlet 20. The lower table included inFIG. 1 depicts information relevant to a low-dead volume version of themicrofluidic circuit 10. The upper table depicts information relevant to a baseline version of themicrofluidic circuit 10 upon which no volume reduction modifications have been made. The total volume of each flow component is depicted inFIG. 1 in Row A of both the upper and lower tables. Theelastomer reservoir 12 supplies the downstream microfluidic circuit flow components with insulin until the elastomer no longer exerts sufficient pressure to overcome the flow resistance in thecircuit 10. At that point, in this example, 87.39 μl of insulin remains in thereservoir 12. See Row D. - Row B in both the upper and lower tables depicts the flow rate Q through the various components. The flow rate Q is defined, at least in part, by flow restrictors and other components present within the circuit. Row C in both the upper and lower tables depicts the amount of time required for insulin to completely fill each dry flow component once flow from the
reservoir 12 is initiated, as the sum of which is the total start-up time for the entiremicrofluidic circuit 10 to fill. This total start-up time reflects the time required to deliver a first dose of insulin to theuser 24. Notably, the difference in volume between a standard flow component 16 (21.22 μl) and a low-dead volume flow component 16 (8.34 μl) contributes directly to the significant reduction in total start-up time of thecircuit 10. Note that the fill time for thestandard flow component 16 is over twice that of the low-dead volume fill time, while the total fill time of the standard circuit is over 1 hour and 15 minutes greater than the microfluidic circuit using a low-dead volume component. This significant delay inherent in the baseline version of thecircuit 10 is both an inconvenience and could be a risk to the user's health. - Row D in both the upper and lower tables depicts the amount of insulin that is effectively trapped within the
microfluidic circuit 10 once theelastomer reservoir 12 can no longer induce flow at theoutlet 20. Note that a significant portion of the trapped insulin, other than that remaining in thereservoir 12, is contained within theflow component 16. Accordingly, use of a low-dead volume flow component, for example, a variable-volume chamber, is advantageous to reduce the total amount of lost insulin within themicrofluidic circuit 10. -
FIG. 2 is a schematic diagram of an exemplary infusion devicemicrofluidic circuit 100 that benefits from the low-dead volume technology described herein. Other infusion device microfluidic circuits benefit as well, such as those described, for example, in U.S. Patent Application Publication No. 2005/0165384 A1, published Jul. 28, 2005, the disclosure of which is hereby incorporated by reference herein in its entirety. Microfluidic circuits having other configurations or utilizing any number of other components also may benefit from inclusion of the low-dead volume variable-volume fluid chamber described herein. Themicrofluidic circuit 100 includes areservoir 102 that is, in this case, comprised of an elastomer bladder. Afill port 104 is used to introduce insulin to themicrofluidic circuit 100. In thismicrofluidic circuit 100, introducing insulin via thefill port 104 fills both thereservoir 102 and a variable-volume bolus reservoir 106. Checkvalves 108 in thecircuit 100 prevent backflow of insulin in a number of locations. - During use, insulin is forced from the
reservoir 102 due to contraction of the elastomer bladder, through afilter 110, and into two parallel flowpaths: abasal flowpath 112 and abolus flowpath 114. Thebasal flowpath 112 delivers a constant dose of insulin to a user; thebolus flowpath 114 delivers a bolus dose of insulin to the user as needed or desired by the user, upon actuation of abolus button 118. Thebasal flowpath 112 includes apressure sensor 116 or other flow sensor in communication with theflowpath 112. To deliver a bolus via thebolus flowpath 114, the user presses thebolus button 118 that drives a single stroke (delivering a single dose) of abolus displacement chamber 120 and opens twovalves 122. Thevalves 122 are in series providing failsafe redundancy for safety purposes.Flow restrictors 124 limit the rate of fluid flow through theflowpaths parallel flowpaths common channel 126, upstream of an internal chamber or acannula void 128. Thecannula void 128 is formed in acannula base 130, that provides a fluidic connection to acannula 132. Thecannula 132 extends below theskin 134 of the user, thus delivering the insulin subcutaneously. In the depictedmicrofluidic circuit 100, reducing the dead volume in the variable-volume bolus reservoir 106 decreases the dead volume throughout the entiremicrofluidic circuit 100. -
FIG. 3 depicts atheoretical flow component 200. While most flow components utilized in a microfluidic circuit serve specific purposes, each generally share several common elements, as depicted inFIG. 3 . First, the flow component includes a housing or some other inner physical boundary that is in contact with the fluid passing therethrough. InFIG. 3 , this innerphysical boundary 202 is depicted as a hollow cube. Second, the flow component includes an inlet, through which fluid flows into the component. InFIG. 3 , theinlet 204 penetrates a wall of thephysical boundary 202 defined by corners bearing the letter “A”; the dimensions of theinlet 204 are defined by a height h, and a width w, although theinlet 204 could be circular or any other shape. Third, the flow component includes an outlet, through which fluid flows out of the component. InFIG. 3 , theoutlet 206 penetrates a wall of thephysical boundary 202 defined by the corners bearing the letter “B”; the dimensions of theoutlet 206 are defined by a height h, and a width w, in this case, matching the dimensions of theinlet 204, although theoutlet 206 could be any shape or size and disposed at any location along theboundary 202. - The inner physical boundary of a flow component defines three volumes: a total volume V, a working volume W, and a dead volume D. The total volume V is the volume bounded by the inner physical boundary; accordingly, in
FIG. 3 , the total volume V is defined by the walls of the cube (i.e., the inner physical boundary 202). The working volume W is the minimum volume required to perform the function of the flow component, including connecting fluidicly the inlet and the outlet. InFIG. 3 , assume that thetheoretical flow component 200 functions as a constant-volume chamber through which fluid passes (where the entire cube must be filled with fluid via theinlet 204 prior to any fluid exiting the cube via the outlet 206). The working volume W is the volume defined around astraight line 208 from a center Ci of theinlet 204 to a center Co of theoutlet 206, the straight line having a length L. The actual volume of this working volume W may be defined, in part, by the total length of straight line L and the height h and width w of theinlet 204 and theoutlet 206, assuming the working volume has outer dimensions substantially similar to height h and width w. Therefore the working volume W may be defined approximately by equation (i) below. -
W=h×w×L (i) - The dead volume D is the volume of the
flow component 200 unnecessary to perform the function, and may be defined as the difference between the total volume V and the working volume W (in this case, the remainder of the volume contained within the innerphysical boundary 202, not including the working volume W), as shown in equation (ii) below. -
D=V−W (ii) - By reducing the dead volume D of a flow component, the dead volume of a microfluidic circuit may be decreased, approaching, ideally, a condition where the total volume of the low-dead volume component VLD equals the working volume W of a standard-dead volume flow component, i.e., VLD=W.
- Different implementations may be utilized to decrease the dead volume of a flow component. In general, however, the dead volume-reduction example described herein may effectively configure the flow component to reduce the dead volume, such that the working volume is substantially the same as the total volume or as close to the total volume as reasonably achievable, under the circumstances. Regardless of the configuration change implemented, a number of factors may be considered. For example, the function and operational performance of the flow component should not be affected adversely by the dead volume-reduction configuration change. The dead volume-reduction change should consider the potential impact on pressure losses associated with the flow component. Care should be taken when reducing dead volume of a flow component, to ensure the component can still be manufactured at acceptable cost. An example of the use of dead volume-reduction configuration change to reduce the dead volume of a flow component is described below.
-
FIG. 4A is a schematic sectional view of a variable-volume chamber 500. Thechamber 500 is formed within asolid housing 502 and has arigid base surface 504, as well as aninlet 506, and anoutlet 508. A rigidtop surface 516 defines the upper surface of thechamber 500. As can be seen inFIG. 4A , the entire volume of aninternal chamber 500 a below aline 510 a must be filled before any fluid may pass out of theoutlet 508. - Depicted in
FIG. 4B is a variable-volume chamber 500′ according to one embodiment of the present invention with reduced dead volume. In this case,membrane 510′ is biased or disposed against therigid base 504 of theinternal chamber 500 a′ to define a first small volume approaching zero, as depicted here. As fluid enters theinternal chamber 500 a′, themembrane 510 a′ expands 512′. The pressure contained withinexpansion volume 514′ is immediately exerted against themembrane 510 a′ and the fluid contained within theinternal chamber 500 a′. Pressure within theexpansion volume 514′ may be relieved by a suitable vent, not shown. Due to the initial location of themembrane 510 a′, once filling begins, pressure is essentially immediately exerted against the fluid, without requiring filling of an excessive dead volume of theinternal chamber 500 a′. - In one embodiment, the variable-
volume chamber 500 depicted inFIG. 4A includes a total volume V of 230 μl. Of this amount, 218.5 μl was determined to be dead volume D and was subsequently reduced bymembrane 510 a′, leaving a working volume W of 11.5 μl. For this embodiment, then, reducing the dead volume D results in a working volume W that is about 5% of the total volume V for the variable-volume chamber 500′ ofFIG. 6B , thus achieving a 95% reduction in the volume of the variable-volume chamber 500. Other reductions are also contemplated. - Application of the low-dead volume technique described herein can significantly reduce dead volume of a
microcircuit 100 such as that depicted inFIG. 2 . As depicted inFIG. 2 , thebasal circuit 112 includes apressure sensor 116 and acannula void 128. Thebolus circuit 114 includes a variable-volume chamber 106 and twovalves 122. The total volume of all conduits in themicrocircuit 100 is about 7 μl, of which nearly none is dead volume. TABLE 1, below, depicts relevant properties of a low-dead volume variable-volume chamber, in an exemplary microcircuit, as that component is described in the Example. Other flow components in an exemplary microcircuit, as depicted in TABLE 1, may include at least acannula void 128,valves 122, and apressure sensor 116. Assuming amicrocircuit 100, such as that depicted inFIG. 2 , the difference in volume of a standard microcircuit (having a baseline-volume fluid chamber) versus the volume of a low-dead volume circuit (having a low-dead volume variable-volume chamber) is depicted. -
TABLE 1 Reduction in Dead Volume for Microcircuit Utilizing Low-Dead Volume Variable-Volume Chamber Improvement Component V (μl) D (μl) W (μl) (% Reduction In V) Bolus Reservoir 230 218.5 11.5 95 106 Other Flow 25.26 0 25.26 0 Components All Conduits 7 0 7 0 Total 262.26 218.5 43.76 83.3 - TABLE 2, below, depicts other relevant properties of a low-dead volume variable-volume chamber, in an exemplary microcircuit, as that component is described in the Example. The total volume V and dead volume D of a standard flow component is provided. Other flow components in an exemplary microcircuit, as depicted in TABLE 2, may include at least a
cannula void 128,valves 122, and apressure sensor 116. In TABLE 2, thecannula void 128 flow component is set aside separately, because its flow rate is different than the other flow components. After utilizing the low-dead volume structure described herein, dead volume D of the variable-volume chamber was essentially eliminated, to achieve the significantly smaller, essentially idealized, working volume W. Also provided is the cumulative volume for all conduits within the microcircuit. - Flow rates Q through each component are also provided. The flow rates Q are used to calculate the fill time for each component. Initially, the fill time for the exemplary fluid chamber is calculated before any dead-volume reduction structure is utilized. In that case, total volume V is divided by the flow rate Q to obtain the fill time for that component. Next, the fill time for the variable-volume chamber is calculated after the dead-volume reduction structure is utilized. In that case, working volume W is divided by the flow rate Q to obtain the fill time for the low-dead volume variable-volume chamber. It should be noted that the working volume is, as defined above, the minimum volume required to perform the function of the flow component. Since the function of the chamber is to hold liquid medicine, it has been assumed here for the purposes of illustration of the concept that a minimum of 11.5 μl is required for the functional working volume. Indeed, the working volume and dead volume of the variable-volume chamber may change as the chamber is made to hold different amounts of liquid medicine.
- Reduction in fill times from that of the standard baseline component to that of the low-dead volume component are also provided. As noted above, while the reduction in fill time for the Example is quite large, this reduction varies depending on the working volume W selected and results in a significant reduction in fill time for the complete circuit.
-
TABLE 2 Reduction in Fill Time for Microcircuit Utilizing Low-Dead Volume Variable- Volume Chamber Flow Fill Fill Fill Time Improvement W Rate Time V Time W Reduc. (% Component V (μl) D (μl) (μl) Q (μl/hr) at Q (hr) at Q (hr) (hr) Reduc.) Cannula Void 1.74 0 1.74 5 0.348 0.348 0 0 128 Bolus 230 218.5 11.5 10 23 1.15 21.85 95 Reservoir 106Other Flow 23.52 0 23.52 10 2.352 2.352 0 0 Components All Conduits 7 0 7 185 0.038 0.038 0 0 Total 262.26 218.5 43.76 N/A 25.738 3.888 21.85 84.9 - The various materials utilized in the flow components described herein, as well as the microfluidic circuits in which those flow components are utilized, may be metal, glass, and/or any type of polymer suitable for sterilization and useful for delivering insulin or other medicaments subcutaneously. Polyurethane, polypropylene, PVC, PVDC, EVA, and others are contemplated for use. More specifically, medical-grade plastics may be utilized for the cannula itself, as well as other components that contact or otherwise penetrate the body of the patient. Needles made from medical-grade stainless steel are also desirable, to prevent failure associated with use. Accordingly, the components utilized to reduce the dead volume within the various components should be the same as, similar to, or at least compatible with the existing materials utilized.
- While there have been described herein what are to be considered exemplary and preferred embodiments of the present invention, other modifications of the invention will become apparent to those skilled in the art from the teachings herein. The particular methods of manufacture and geometries disclosed herein are exemplary in nature and are not to be considered limiting. It is therefore desired to be secured in the appended claims all such modifications as fall within the spirit and scope of the invention. Accordingly, what is desired to be secured by Letters Patent is the invention as defined and differentiated in the following claims, and all equivalents.
Claims (5)
1. A method for reducing a dead volume of a microfluidic circuit comprising a reservoir, an outlet, and a microfluidic flowpath fluidly connecting the reservoir and the outlet, the method comprising:
providing a variable-volume fluid chamber located between the reservoir and the outlet for performing a function and in fluidic communication with the microfluidic flowpath,
wherein the variable-volume fluid chamber comprises a total volume comprising a working volume and a dead volume, wherein the working volume comprises a volume necessary for the variable-volume fluid chamber to perform the function and the dead volume comprises a volume unnecessary for the variable-volume fluid chamber to perform the function; and
configuring the variable-volume fluid chamber to reduce the dead volume, such that the working volume is substantially the same as the total volume.
2. The method of claim 1 , wherein the configuring step results in the total volume being substantially the same as the working volume.
3. The method of claim 1 , wherein the variable-volume fluid chamber comprises a base surface, an inlet, and a separate outlet, and wherein the configuring step comprises:
providing a flexible membrane wherein the base surface and the membrane define a first volume when the membrane is proximate the base surface, wherein the base surface and the membrane define a second volume when the membrane is displaced by a fluid pressure away from the base surface, and wherein the membrane is biased towards the base surface.
4. A low-dead volume variable-volume fluid chamber manufactured in accordance with the method of claim 3 .
5. The low-dead volume variable-volume fluid chamber of claim 4 , wherein the working volume comprises about 5% of the total volume.
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US12/436,365 US8230744B2 (en) | 2009-05-06 | 2009-05-06 | Low-dead volume microfluidic circuit and methods |
EP17192248.7A EP3287161A1 (en) | 2009-05-06 | 2010-05-05 | Low-dead volume microfluidic circuit and methods |
PCT/IB2010/001211 WO2010128399A2 (en) | 2009-05-06 | 2010-05-05 | Low-dead volume microfluidic circuit and methods |
EP10728883A EP2427235A2 (en) | 2009-05-06 | 2010-05-05 | Low-dead volume microfluidic circuit and methods |
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Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN106716097A (en) * | 2014-09-25 | 2017-05-24 | 英福康有限责任公司 | Device and method for calibrating film chamber for leak detection |
WO2018122174A1 (en) * | 2016-12-28 | 2018-07-05 | Cequr Sa | Microfluidic flow restrictor and system |
Citations (47)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3144879A (en) * | 1963-03-12 | 1964-08-18 | Hans D Baumann | Adjustable laminar flow restriction |
US3722756A (en) * | 1971-07-19 | 1973-03-27 | Roycraft Ind | Method and apparatus for storing and dispensing effervescent beverages |
US3880151A (en) * | 1972-07-12 | 1975-04-29 | Siemens Elema Ab | Pressure receiver |
US3904111A (en) * | 1972-05-23 | 1975-09-09 | Volvo Penta Ab | Temperature responsive flow regulating laminated conduit |
US3977600A (en) * | 1975-11-06 | 1976-08-31 | J. I. Case Company | Temperature responsive fluid flow regulator |
US4398542A (en) * | 1980-12-15 | 1983-08-16 | Ivac Corporation | Pressure diaphragm |
US4759883A (en) * | 1987-03-12 | 1988-07-26 | Walbro Corporation | Temperature compensated fluid flow metering system |
US5176358A (en) * | 1991-08-08 | 1993-01-05 | Honeywell Inc. | Microstructure gas valve control |
US5271724A (en) * | 1990-08-31 | 1993-12-21 | Westonbridge International Limited | Valve equipped with a position detector and a micropump incorporating said valve |
US5306257A (en) * | 1992-05-04 | 1994-04-26 | Prime Medical Products, Inc. | Drug infuser |
US5360411A (en) * | 1992-10-12 | 1994-11-01 | Opto Tech Co., Ltd. | Liquid medicine injecting device |
US5810325A (en) * | 1996-06-25 | 1998-09-22 | Bcam International, Inc. | Microvalve |
US5839467A (en) * | 1993-10-04 | 1998-11-24 | Research International, Inc. | Micromachined fluid handling devices |
US6056269A (en) * | 1999-01-15 | 2000-05-02 | Hewlett-Packard Company | Microminiature valve having silicon diaphragm |
US6068751A (en) * | 1995-12-18 | 2000-05-30 | Neukermans; Armand P. | Microfluidic valve and integrated microfluidic system |
US6227824B1 (en) * | 1995-09-15 | 2001-05-08 | HAN-SCHICKARD-GESELLSCHAFT FüR ANGEWANDTE FORSCHUNG E.V. | Fluid pump without non-return valves |
US20030015682A1 (en) * | 2001-07-17 | 2003-01-23 | Kevin Killeen | Flow-switching microdevice |
US6589229B1 (en) * | 2000-07-31 | 2003-07-08 | Becton, Dickinson And Company | Wearable, self-contained drug infusion device |
US6644944B2 (en) * | 2000-11-06 | 2003-11-11 | Nanostream, Inc. | Uni-directional flow microfluidic components |
US6713151B1 (en) * | 1998-06-24 | 2004-03-30 | Honeywell International Inc. | Compliant fibrous thermal interface |
US6716193B1 (en) * | 1996-12-18 | 2004-04-06 | Debiotech S.A. | Medical device for injecting liquid |
US20040104173A1 (en) * | 2001-04-06 | 2004-06-03 | Michel Manach | Installation for treating samples continuously by separation on a stationary phase under forced flow |
US20040209354A1 (en) * | 2002-12-30 | 2004-10-21 | The Regents Of The University Of California | Fluid control structures in microfluidic devices |
US20040245102A1 (en) * | 2002-09-09 | 2004-12-09 | Gilbert John R. | Implementation of microfluidic components, including molecular fractionation devices, in a microfluidic system |
US20050013732A1 (en) * | 2003-01-21 | 2005-01-20 | Micronics, Inc. | Method and system for microfluidic manipulation, amplification and analysis of fluids, for example, bacteria assays and antiglobulin testing |
US6852094B2 (en) * | 2001-04-16 | 2005-02-08 | Zevex, Inc. | Infusion set adaptor |
US20050045733A1 (en) * | 2002-07-12 | 2005-03-03 | Phipps Anthony B. | Gate arrangement |
US6919046B2 (en) * | 2001-06-07 | 2005-07-19 | Nanostream, Inc. | Microfluidic analytical devices and methods |
US20050205816A1 (en) * | 2001-04-03 | 2005-09-22 | Micronics, Inc. | Pneumatic valve interface for use in microfluidic structures |
US6948373B2 (en) * | 2003-06-20 | 2005-09-27 | Surpass Industry Co., Ltd. | Inline pressure sensor |
US20050255003A1 (en) * | 2002-09-06 | 2005-11-17 | Philip Summersgill | Modular microfluidic system |
US20050266582A1 (en) * | 2002-12-16 | 2005-12-01 | Modlin Douglas N | Microfluidic system with integrated permeable membrane |
US20060000238A1 (en) * | 2004-06-12 | 2006-01-05 | Teresanne Griffin | Capillary column for filtering, separation and concentration |
US20060011882A1 (en) * | 2002-09-13 | 2006-01-19 | Danfoss A/S | Control Valve with Elastomeric Valve Element |
US20060169702A1 (en) * | 2005-01-31 | 2006-08-03 | Shen Chuan C | Pressure container |
US20060184121A1 (en) * | 2005-02-11 | 2006-08-17 | Brockman Christopher S | Reprogrammable fluid delivery system and method of use |
US7094379B2 (en) * | 2001-10-24 | 2006-08-22 | Commissariat A L'energie Atomique | Device for parallel and synchronous injection for sequential injection of different reagents |
US7143787B1 (en) * | 2004-05-22 | 2006-12-05 | Agilent Technologies, Inc. | Microluidic valve having two revolving valve elements |
US7152616B2 (en) * | 2002-12-04 | 2006-12-26 | Spinx, Inc. | Devices and methods for programmable microscale manipulation of fluids |
US20070003448A1 (en) * | 2004-03-12 | 2007-01-04 | Kanigan Tanya S | Nanoliter array loading |
US7159618B2 (en) * | 2003-06-16 | 2007-01-09 | Bio{acute over (m)}erieux | Electrically opened micro fluid valve |
US7207345B2 (en) * | 2002-09-24 | 2007-04-24 | The Technology Partnership Plc | Fluid routing device |
US7244961B2 (en) * | 2002-08-02 | 2007-07-17 | Silicon Valley Scientific | Integrated system with modular microfluidic components |
US7291126B2 (en) * | 2001-11-26 | 2007-11-06 | Nilimedix Ltd. | Drug delivery device and method |
US20080029169A1 (en) * | 2002-09-25 | 2008-02-07 | California Institute Of Technology | Microfluidic large scale integration |
US20080234630A1 (en) * | 2005-05-17 | 2008-09-25 | Medingo Ltd | Disposable Dispenser for Patient Infusion |
US20080281276A1 (en) * | 2007-05-10 | 2008-11-13 | Nilimedix Ltd. | Infusion set self-occlusion mechanism |
-
2009
- 2009-05-06 US US12/436,360 patent/US20100282766A1/en not_active Abandoned
Patent Citations (48)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3144879A (en) * | 1963-03-12 | 1964-08-18 | Hans D Baumann | Adjustable laminar flow restriction |
US3722756A (en) * | 1971-07-19 | 1973-03-27 | Roycraft Ind | Method and apparatus for storing and dispensing effervescent beverages |
US3904111A (en) * | 1972-05-23 | 1975-09-09 | Volvo Penta Ab | Temperature responsive flow regulating laminated conduit |
US3880151A (en) * | 1972-07-12 | 1975-04-29 | Siemens Elema Ab | Pressure receiver |
US3977600A (en) * | 1975-11-06 | 1976-08-31 | J. I. Case Company | Temperature responsive fluid flow regulator |
US4398542A (en) * | 1980-12-15 | 1983-08-16 | Ivac Corporation | Pressure diaphragm |
US4759883A (en) * | 1987-03-12 | 1988-07-26 | Walbro Corporation | Temperature compensated fluid flow metering system |
US5271724A (en) * | 1990-08-31 | 1993-12-21 | Westonbridge International Limited | Valve equipped with a position detector and a micropump incorporating said valve |
US5176358A (en) * | 1991-08-08 | 1993-01-05 | Honeywell Inc. | Microstructure gas valve control |
US5306257A (en) * | 1992-05-04 | 1994-04-26 | Prime Medical Products, Inc. | Drug infuser |
US5360411A (en) * | 1992-10-12 | 1994-11-01 | Opto Tech Co., Ltd. | Liquid medicine injecting device |
US5839467A (en) * | 1993-10-04 | 1998-11-24 | Research International, Inc. | Micromachined fluid handling devices |
US6227824B1 (en) * | 1995-09-15 | 2001-05-08 | HAN-SCHICKARD-GESELLSCHAFT FüR ANGEWANDTE FORSCHUNG E.V. | Fluid pump without non-return valves |
US6068751A (en) * | 1995-12-18 | 2000-05-30 | Neukermans; Armand P. | Microfluidic valve and integrated microfluidic system |
US5810325A (en) * | 1996-06-25 | 1998-09-22 | Bcam International, Inc. | Microvalve |
US6716193B1 (en) * | 1996-12-18 | 2004-04-06 | Debiotech S.A. | Medical device for injecting liquid |
US6713151B1 (en) * | 1998-06-24 | 2004-03-30 | Honeywell International Inc. | Compliant fibrous thermal interface |
US6056269A (en) * | 1999-01-15 | 2000-05-02 | Hewlett-Packard Company | Microminiature valve having silicon diaphragm |
US6589229B1 (en) * | 2000-07-31 | 2003-07-08 | Becton, Dickinson And Company | Wearable, self-contained drug infusion device |
US6644944B2 (en) * | 2000-11-06 | 2003-11-11 | Nanostream, Inc. | Uni-directional flow microfluidic components |
US20050205816A1 (en) * | 2001-04-03 | 2005-09-22 | Micronics, Inc. | Pneumatic valve interface for use in microfluidic structures |
US20040104173A1 (en) * | 2001-04-06 | 2004-06-03 | Michel Manach | Installation for treating samples continuously by separation on a stationary phase under forced flow |
US6852094B2 (en) * | 2001-04-16 | 2005-02-08 | Zevex, Inc. | Infusion set adaptor |
US6919046B2 (en) * | 2001-06-07 | 2005-07-19 | Nanostream, Inc. | Microfluidic analytical devices and methods |
US20030015682A1 (en) * | 2001-07-17 | 2003-01-23 | Kevin Killeen | Flow-switching microdevice |
US7094379B2 (en) * | 2001-10-24 | 2006-08-22 | Commissariat A L'energie Atomique | Device for parallel and synchronous injection for sequential injection of different reagents |
US7291126B2 (en) * | 2001-11-26 | 2007-11-06 | Nilimedix Ltd. | Drug delivery device and method |
US20050045733A1 (en) * | 2002-07-12 | 2005-03-03 | Phipps Anthony B. | Gate arrangement |
US7244961B2 (en) * | 2002-08-02 | 2007-07-17 | Silicon Valley Scientific | Integrated system with modular microfluidic components |
US20050255003A1 (en) * | 2002-09-06 | 2005-11-17 | Philip Summersgill | Modular microfluidic system |
US7094345B2 (en) * | 2002-09-09 | 2006-08-22 | Cytonome, Inc. | Implementation of microfluidic components, including molecular fractionation devices, in a microfluidic system |
US20040245102A1 (en) * | 2002-09-09 | 2004-12-09 | Gilbert John R. | Implementation of microfluidic components, including molecular fractionation devices, in a microfluidic system |
US20060011882A1 (en) * | 2002-09-13 | 2006-01-19 | Danfoss A/S | Control Valve with Elastomeric Valve Element |
US7207345B2 (en) * | 2002-09-24 | 2007-04-24 | The Technology Partnership Plc | Fluid routing device |
US20080029169A1 (en) * | 2002-09-25 | 2008-02-07 | California Institute Of Technology | Microfluidic large scale integration |
US7152616B2 (en) * | 2002-12-04 | 2006-12-26 | Spinx, Inc. | Devices and methods for programmable microscale manipulation of fluids |
US20050266582A1 (en) * | 2002-12-16 | 2005-12-01 | Modlin Douglas N | Microfluidic system with integrated permeable membrane |
US20040209354A1 (en) * | 2002-12-30 | 2004-10-21 | The Regents Of The University Of California | Fluid control structures in microfluidic devices |
US20050013732A1 (en) * | 2003-01-21 | 2005-01-20 | Micronics, Inc. | Method and system for microfluidic manipulation, amplification and analysis of fluids, for example, bacteria assays and antiglobulin testing |
US7159618B2 (en) * | 2003-06-16 | 2007-01-09 | Bio{acute over (m)}erieux | Electrically opened micro fluid valve |
US6948373B2 (en) * | 2003-06-20 | 2005-09-27 | Surpass Industry Co., Ltd. | Inline pressure sensor |
US20070003448A1 (en) * | 2004-03-12 | 2007-01-04 | Kanigan Tanya S | Nanoliter array loading |
US7143787B1 (en) * | 2004-05-22 | 2006-12-05 | Agilent Technologies, Inc. | Microluidic valve having two revolving valve elements |
US20060000238A1 (en) * | 2004-06-12 | 2006-01-05 | Teresanne Griffin | Capillary column for filtering, separation and concentration |
US20060169702A1 (en) * | 2005-01-31 | 2006-08-03 | Shen Chuan C | Pressure container |
US20060184121A1 (en) * | 2005-02-11 | 2006-08-17 | Brockman Christopher S | Reprogrammable fluid delivery system and method of use |
US20080234630A1 (en) * | 2005-05-17 | 2008-09-25 | Medingo Ltd | Disposable Dispenser for Patient Infusion |
US20080281276A1 (en) * | 2007-05-10 | 2008-11-13 | Nilimedix Ltd. | Infusion set self-occlusion mechanism |
Cited By (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN106716097A (en) * | 2014-09-25 | 2017-05-24 | 英福康有限责任公司 | Device and method for calibrating film chamber for leak detection |
WO2018122174A1 (en) * | 2016-12-28 | 2018-07-05 | Cequr Sa | Microfluidic flow restrictor and system |
US10258741B2 (en) | 2016-12-28 | 2019-04-16 | Cequr Sa | Microfluidic flow restrictor and system |
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