Patent Application
20110034829
This application claims the benefit of U.S. Ser. No. 60/724,073, filed Oct. 05, 2005, which application is fully incorporated herein by reference.
1. Technical Field
The technical field relates to analyte detecting devices, and more specifically, coatings for improving glucose measurement.
2. Background Art
Lancing devices are known in the medical health-care products industry for piercing the skin to produce blood for analysis. Typically, a drop of blood for this type of analysis is obtained by making a small incision in the fingertip, creating a small wound, which generates a small blood droplet on the surface of the skin.
Early methods of lancing included piercing or slicing the skin with a needle or razor. Current methods utilize lancing devices that contain a multitude of spring, cam and mass actuators to drive the lancet. These include cantilever springs, diaphragms, coil springs, as well as gravity plumbs used to drive the lancet. The device may be held against the skin and mechanically triggered to ballistically launch the lancet. Unfortunately, the pain associated with each lancing event using known technology discourages patients from testing. In addition to vibratory stimulation of the skin as the driver impacts the end of a launcher stop, known spring based devices have the possibility of firing lancets that harmonically oscillate against the patient tissue, causing multiple strikes due to recoil. This recoil and multiple strikes of the lancet is one major impediment to patient compliance with a structured glucose monitoring regime.
Success rate generally encompasses the probability of producing a blood sample with one lancing action, which is sufficient in volume to perform the desired analytical test. The blood may appear spontaneously at the surface of the skin, or may be “milked” from the wound. Milking generally involves pressing the side of the digit, or in proximity of the wound to express the blood to the surface. In traditional methods, the blood droplet produced by the lancing action may reach the surface of the skin to be viable for testing.
When using existing methods, blood often flows from the cut blood vessels but is then trapped below the surface of the skin, forming a hematoma. In other instances, a wound is created, but no blood flows from the wound. In either case, the lancing process cannot be combined with the sample acquisition and testing step. Spontaneous blood droplet generation with current mechanical launching system varies between launcher types but on average it is about 50% of lancet strikes, which would be spontaneous. Otherwise milking is required to yield blood. Mechanical launchers are unlikely to provide the means for integrated sample acquisition and testing if one out of every two strikes does not yield a spontaneous blood sample.
Many diabetic patients (insulin dependent) are required to self-test for blood glucose levels five to six times daily. The large number of steps required in traditional methods of glucose testing ranging from lancing, to milking of blood, applying blood to the test strip, and getting the measurements from the test strip discourages many diabetic patients from testing their blood glucose levels as often as recommended. Tight control of plasma glucose through frequent testing is therefore mandatory for disease management. The pain associated with each lancing event further discourages patients from testing. Additionally, the wound channel left on the patient by known systems may also be of a size that discourages those who are active with their hands or who are worried about healing of those wound channels from testing their glucose levels.
Another problem frequently encountered by patients who may use lancing equipment to obtain and analyze blood samples is the amount of manual dexterity and hand-eye coordination required to properly operate the lancing and sample testing equipment due to retinopathies and neuropathies particularly, severe in elderly diabetic patients. For those patients, operating existing lancet and sample testing equipment can be a challenge. Once a blood droplet is created, that droplet must then be guided into a receiving channel of a small test strip or the like. If the sample placement on the strip is unsuccessful, repetition of the entire procedure including re-lancing the skin to obtain a new blood droplet is desired.
Early methods of using test strips required a relatively substantial volume of blood to obtain an accurate glucose measurement. This large blood requirement made the monitoring experience a painful one for the user since the user may need to lance deeper than comfortable to obtain sufficient blood generation. Alternatively, if insufficient blood is spontaneously generated, the user may need to “milk” the wound to squeeze enough blood to the skin surface. Neither method is desirable as they take additional user effort and may be painful. The discomfort and inconvenience associated with such lancing events may deter a user from testing their blood glucose levels in a rigorous manner sufficient to control their diabetes.
A further impediment to patient compliance is the amount of time that at lower volumes, it becomes even more important that blood or other fluid sample be directed to a measurement device without being wasted or spilled along the way. Known devices do not effectively handle the low sample volumes in an efficient manner Accordingly, improved sensing devices are desired to increase user compliance and reduce the hurdles associated with analyte measurement.
An object of the present invention is to provide an analyte detecting apparatus that has improved measurement of analyte levels in a body fluid.
Another object of the present invention is to provide an improved method of manufacturing analyte detecting devices.
These and other objects of the present invention are achieved in a device that has a cartridge with a plurality of cavities. A plurality of penetrating members are at least partially contained in the cavities of the cartridge. The penetrating members are movable to extend outward from lateral openings on the cartridge to penetrate tissue. A sterility barrier is coupled to the cartridge. The sterility barrier covers the lateral openings and is at least partially movable to provide that a penetrating member exits the lateral opening without contacting the sterility barrier. A plurality of analyte detecting members are coupled to the cartridge. The analyte detecting members are associated with sample chambers. A plurality of sample capture devices are coupled to the sample chambers. The sample capture devices each have an opening to allow a penetrating member to pass through.
In another embodiment of the present invention, a method if provided of manufacturing an analyte detecting device. A cartridge is sized to fit within a housing. An opening is formed on the housing. At least one layer of viscoelastic material is applied on the housing around the opening. The material applies an compression force to a target tissue when the target tissue engages the material. A plurality of penetrating members are in the cartridge. A plurality of analyte detection devices are in the cartridge.
Referring now to
It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the invention, as claimed. It may be noted that, as used in the specification and the appended claims, the singular forms “a”, “an” and “the” include plural referents unless the context clearly dictates otherwise. Thus, for example, reference to “a material” may include mixtures of materials, reference to “a chamber” may include multiple chambers, and the like. References cited herein are hereby incorporated by reference in their entirety, except to the extent that they conflict with teachings explicitly set forth in this specification.
In this specification and in the claims which follow, reference will be made to a number of terms which shall be defined to have the following meanings:
“Optional” or “optionally” means that the subsequently described circumstance may or may not occur, so that the description includes instances where the circumstance occurs and instances where it does not. For example, if a device optionally contains a feature for analyzing a blood sample, this means that the analysis feature may or may not be present, and, thus, the description includes structures wherein a device possesses the analysis feature and structures wherein the analysis feature is not present.
The present invention may be used with a variety of different penetrating member drivers. It is contemplated that these penetrating member drivers may be spring based, solenoid based, magnetic driver based, nanomuscle based, or based on any other mechanism useful in moving a penetrating member along a path into tissue. It should be noted that the present invention is not limited by the type of driver used with the penetrating member feed mechanism. One suitable penetrating member driver for use with the present invention is shown in
Referring to the embodiment of
As discussed above, tissue penetration devices which employ spring or cam driving methods have a symmetrical or nearly symmetrical actuation displacement and velocity profiles on the advancement and retraction of the penetrating member as shown in
In this embodiment, the ability to control velocity and depth of penetration may be achieved by use of a controllable force driver where feedback is an integral part of driver control. Such drivers can control either metal or polymeric penetrating members or any other type of tissue penetration element. The dynamic control of such a driver is illustrated in
After the lancing event, the processor 60 can allow the user to rank the results of the lancing event. The processor 60 stores these results and constructs a database 80 for the individual user. Using the database 79, the processor 60 calculates the profile traits such as degree of painlessness, success rate, and blood volume for various profiles 62 depending on user input information 64 to optimize the profile to the individual user for subsequent lancing cycles. These profile traits depend on the characteristic phases of penetrating member advancement and retraction. The processor 60 uses these calculations to optimize profiles 62 for each user. In addition to user input information 64, an internal clock allows storage in the database 79 of information such as the time of day to generate a time stamp for the lancing event and the time between lancing events to anticipate the user's diurnal needs. The database stores information and statistics for each user and each profile that particular user uses.
In addition to varying the profiles, the processor 60 can be used to calculate the appropriate penetrating member diameter and geometry suitable to realize the blood volume required by the user. For example, if the user requires about 1-5 microliter volume of blood, the processor 60 may select a 200 micron diameter penetrating member to achieve these results. For each class of penetrating member, both diameter and penetrating member tip geometry, is stored in the processor 60 to correspond with upper and lower limits of attainable blood volume based on the predetermined displacement and velocity profiles.
The lancing device is capable of prompting the user for information at the beginning and the end of the lancing event to more adequately suit the user. The goal is to either change to a different profile or modify an existing profile. Once the profile is set, the force driving the penetrating member is varied during advancement and retraction to follow the profile. The method of lancing using the lancing device comprises selecting a profile, lancing according to the selected profile, determining lancing profile traits for each characteristic phase of the lancing cycle, and optimizing profile traits for subsequent lancing events.
Referring to
A magnetic member 102 is secured to the elongate coupler shaft 84 proximal of the drive coupler 85 on a distal portion 203 of the elongate coupler shaft 84. The magnetic member 102 is a substantially cylindrical piece of magnetic material having an axial lumen 204 extending the length of the magnetic member 102. The magnetic member 102 has an outer transverse dimension that allows the magnetic member 102 to slide easily within an axial lumen 105 of a low friction, possibly lubricious, polymer guide tube 105′ disposed within the driver coil pack 88. The magnetic member 102 may have an outer transverse dimension of about 1.0 to about 5.0 mm, specifically, about 2.3 to about 2.5 mm. The magnetic member 102 may have a length of about 3.0 to about 5.0 mm, specifically, about 4.7 to about 4.9 mm. The magnetic member 102 can be made from a variety of magnetic materials including ferrous metals such as ferrous steel, iron, ferrite, or the like. The magnetic member 102 may be secured to the distal portion 203 of the elongate coupler shaft 84 by a variety of methods including adhesive or epoxy bonding, welding, crimping or any other suitable method.
Proximal of the magnetic member 102, an optical encoder flag 206 is secured to the elongate coupler shaft 84. The optical encoder flag 206 is configured to move within a slot 107 in the position sensor 91. The slot 107 of the position sensor 91 is formed between a first body portion 108 and a second body portion 109 of the position sensor 91. The slot 107 may have separation width of about 1.5 to about 2.0 mm. The optical encoder flag 206 can have a length of about 14 to about 18 mm, a width of about 3 to about 5 mm and a thickness of about 0.04 to about 0.06 mm.
The optical encoder flag 206 interacts with various optical beams generated by LEDs disposed on or in the position sensor body portions 108 and 109 in a predetermined manner. The interaction of the optical beams generated by the LEDs of the position sensor 91 generates a signal that indicates the longitudinal position of the optical flag 206 relative to the position sensor 91 with a substantially high degree of resolution. The resolution of the position sensor 91 may be about 200 to about 400 cycles per inch, specifically, about 350 to about 370 cycles per inch. The position sensor 91 may have a speed response time (position/time resolution) of 0 to about 120,000 Hz, where one dark and light stripe of the flag constitutes one Hertz, or cycle per second. The position of the optical encoder flag 206 relative to the magnetic member 102, driver coil pack 88 and position sensor 91 is such that the optical encoder 91 can provide precise positional information about the penetrating member 83 over the entire length of the penetrating member's power stroke.
An optical encoder that is suitable for the position sensor 91 is a linear optical incremental encoder, model HEDS 9200, manufactured by Agilent Technologies. The model HEDS 9200 may have a length of about 20 to about 30 mm, a width of about 8 to about 12 mm, and a height of about 9 to about 11 mm. Although the position sensor 91 illustrated is a linear optical incremental encoder, other suitable position sensor embodiments could be used, provided they posses the requisite positional resolution and time response. The HEDS 9200 is a two channel device where the channels are 90 degrees out of phase with each other. This results in a resolution of four times the basic cycle of the flag. These quadrature outputs make it possible for the processor to determine the direction of penetrating member travel. Other suitable position sensors include capacitive encoders, analog reflective sensors, such as the reflective position sensor discussed above, and the like.
A coupler shaft guide 111 is disposed towards the proximal end 81 of the lancing device 80. The guide 111 has a guide lumen 112 disposed in the guide 111 to slidingly accept the proximal portion 92 of the elongate coupler shaft 84. The guide 111 keeps the elongate coupler shaft 84 centered horizontally and vertically in the slot 102 of the optical encoder 91.
Referring now to
Each penetrating member 302 may be contained in a cavity 306 in the cartridge 300 with the penetrating member's sharpened end facing radially outward and may be in the same plane as that of the cartridge. The cavity 306 may be molded, pressed, forged, or otherwise formed in the cartridge. Although not limited in this manner, the ends of the cavities 306 may be divided into individual fingers (such as one for each cavity) on the outer periphery of the disc. The particular shape of each cavity 306 may be designed to suit the size or shape of the penetrating member therein or the amount of space desired for placement of the analyte detecting members 808. For example and not limitation, the cavity 306 may have a V-shaped cross-section, a U-shaped cross-section, C-shaped cross-section, a multi-level cross section or the other cross-sections. The opening 810 through which a penetrating member 302 may exit to penetrate tissue may also have a variety of shapes, such as but not limited to, a circular opening, a square or rectangular opening, a U-shaped opening, a narrow opening that only allows the penetrating member to pass, an opening with more clearance on the sides, a slit, a configuration as shown in
In this embodiment, after actuation, the penetrating member 302 is returned into the cartridge and may be held within the cartridge 300 in a manner so that it is not able to be used again. By way of example and not limitation, a used penetrating member may be returned into the cartridge and held by the launcher in position until the next lancing event. At the time of the next lancing, the launcher may disengage the used penetrating member with the cartridge 300 turned or indexed to the next clean penetrating member such that the cavity holding the used penetrating member is position so that it is not accessible to the user (i.e. turn away from a penetrating member exit opening). In some embodiments, the tip of a used penetrating member may be driven into a protective stop that hold the penetrating member in place after use. The cartridge 300 is replaceable with a new cartridge 300 once all the penetrating members have been used or at such other time or condition as deemed desirable by the user.
Referring still to the embodiment in
Depending on the orientation of the cartridge 300 in the penetrating member driver apparatus, the seal layer 320 may be on the top surface, side surface, bottom surface, or other positioned surface. For ease of illustration and discussion of the embodiment of
In a still further feature of
The use of the seal layer 320 and substrate or analyte detecting member layer 822 may facilitate the manufacture of these cartridges 10. For example, a single seal layer 320 may be adhered, attached, or otherwise coupled to the cartridge 300 as indicated by arrows 324 to seal many of the cavities 306 at one time. A sheet 322 of analyte detecting members may also be adhered, attached, or otherwise coupled to the cartridge 300 as indicated by arrows 325 to provide many analyte detecting members on the cartridge at one time. During manufacturing of one embodiment of the present invention, the cartridge 300 may be loaded with penetrating members 302, sealed with layer 320 and a temporary layer (not shown) on the bottom where substrate 322 would later go, to provide a sealed environment for the penetrating members. This assembly with the temporary bottom layer is then taken to be sterilized. After sterilization, the assembly is taken to a clean room (or it may already be in a clear room or equivalent environment) where the temporary bottom layer is removed and the substrate 322 with analyte detecting members is coupled to the cartridge as shown in
In some embodiments, more than one seal layer 320 may be used to seal the cavities 306. As examples of some embodiments, multiple layers may be placed over each cavity 306, half or some selected portion of the cavities may be sealed with one layer with the other half or selected portion of the cavities sealed with another sheet or layer, different shaped cavities may use different seal layer, or the like. The seal layer 320 may have different physical properties, such as those covering the penetrating members 302 near the end of the cartridge may have a different color such as red to indicate to the user (if visually inspectable) that the user is down to say 10, 5, or other number of penetrating members before the cartridge should be changed out.
Referring now to
The current preferred embodiment for cartridge 400 came about through discussions about how to solve the sealing for moisture protection challenge as well as an alternative to the through hole connector solution. The general configuration for sample capture and detecting member fill and attachment of the detecting member ring are shown. The paradigm of a 50 penetrating member disposable with a single molded support is simple compared to other solutions where 50 penetrating members bearing 50 molded chucks and sterility caps are placed in a disk, drum or bandolier, and the number of moving parts can exceed the number of penetrating members or tests in general!
Extending the penetrating member disk 410 idea and attaching a 50-detecting member ring to the bottom of the 50 penetrating member disk seems an appropriate within the context of the penetrating member lancing device paradigm, though it requires a shift from the current premise of packaging single detecting members into a disposable carrying 50 single detecting members for which the industry seems more prepared to manufacture.
Components
As seen in
In one embodiment of the present invention, a cartridge is provided with a plurality of cavities. A plurality of penetrating members are at least partially contained in the cavities of the cartridge. The penetrating members are movable to extend outward from lateral openings on the cartridge to penetrate tissue. A sterility barrier is coupled to the cartridge. The sterility barrier covers the lateral openings and is at least partially movable to provide that a penetrating member exits the lateral opening without contacting the sterility barrier. A plurality of analyte detecting members are coupled to the cartridge. The analyte detecting members are associated with sample chambers. A plurality of sample capture devices are coupled to the sample chambers. The sample capture devices each have an opening to allow a penetrating member to pass through.
In another embodiment of the present invention, a method if provided of manufacturing an analyte detecting device. A cartridge is sized to fit within a housing. An opening is formed on the housing. At least one layer of viscoelastic material is applied on the housing around the opening. The material applies an compression force to a target tissue when the target tissue engages the material. A plurality of penetrating members are in the cartridge. A plurality of analyte detection devices are in the cartridge.
In one embodiment as seen in
The detecting members will be screen-printed the same as in the current method up to the level of the hydrophobic PSA. The laminate film containing the “rib” features will be aligned and pressed on to the detecting member. The ribs (or slits) will be laser cut, and the laminate aligned to screen-printed features. The density of the detecting members per sheet has been estimated for 120°, 180° and 360° arcs. Comparable packing densities are achievable because the “handle” of the lollipop is not needed (this function is provided by the laminate which is inside (and forms a part) the detecting member channel, and there is no longer a space needed between every detecting member for cuffing/punching into individual “Chiclets”. The 120° nested layout produces the most detecting member per sheet at 2132. The challenge will be to connect the arcs into a single ring for assembly on to the penetrating member disk 410.
Functional Performance
Referring now to
The front face is designed to be opened by the plough method, which currently the preferred method for Titan. The front dace will be sealed with foil, probably using the radial heat seal rig. The finger may contact the ring inside of the front face window, which may require some design optimization for correct finger placement. Work on the plough design might achieve this; conversely some features on the sample inlet aperture may also address the problem of correct finger positioning to capture blood from the wound.
Instrument Interface
Referring now to
Sample Capture
A two-pronged approach to investigating a sample capture strategy for cartridge 400 was employed, lab experiments using a test rig of the preferred embodiment and theoretical simulation of same. The object is to identify the geometry best suited for the filling of the sample channel and to discover potential risks that may influence the desired filling.
Preferred embodiments of sample capture and detecting member fill configurations were derived at a workshop held in Toft on Apr. 26-27 2005 ADX-0028-D-A Ecoburger Phase 1 Sample capture, detecting member layout and sealing. From the workshop three major concepts for sample capture and detecting member layout were chosen for testing and simulation, as they were deemed best suited to rapid development.
In A and B the disposable has no sample capture structure. In A the glucose detecting member is placed in the penetrating member tunnel and relies on the penetrating member acting as the cover slip. In B (Bravo) three “ribs” cover the detecting member and opposed to one “rib” in E (Echo). C (Charlie) has the sample capture structure of the Titan “Huygens” detecting member with a three rib configuration. D was considered high risk and not pursued.
Referring now to
While the invention has been described and illustrated with reference to certain particular embodiments thereof, those skilled in the art will appreciate that various adaptations, changes, modifications, substitutions, deletions, or additions of procedures and protocols may be made without departing from the spirit and scope of the invention. For example, with any of the above embodiments, the dissolvable seal may or may not be included.
The publications discussed or cited herein are provided solely for their disclosure prior to the filing date of the present application. Nothing herein is to be construed as an admission that the present invention is not entitled to antedate such publication by virtue of prior invention. Further, the dates of publication provided may be different from the actual publication dates which may need to be independently confirmed. All publications mentioned herein are incorporated herein by reference to disclose and describe the structures and/or methods in connection with which the publications are cited. U.S. Provisional applications Ser. Nos. 60/610,305, 60/610,360,and 60/611,094 are fully incorporated herein by reference for all purposes.
Expected variations or differences in the results are contemplated in accordance with the objects and practices of the present invention. It is intended, therefore, that the invention be defined by the scope of the claims which follow and that such claims be interpreted as broadly as is reasonable.
| Number | Date | Country | |
|---|---|---|---|
| 20070123802 A1 | May 2007 | US |
| Number | Date | Country | |
|---|---|---|---|
| 60724073 | Oct 2005 | US |
| Number | Date | Country | |
|---|---|---|---|
| Parent | 10237261 | Sep 2002 | US |
| Child | 11534977 | Sep 2006 | US |
