Patent Application
20090318876
The present invention relates to various arrangements comprising an electromagnetic device adapted to generate a magnetic field having a spatial overlap with a medicament, such as insulin, contained in a medication delivery device, a medicament containing cartridge or the like. The electromagnetic device forms an integral part of an oscillating circuit having a well-defined resonance frequency and an associated Q-factor. The resonance frequency and Q-factor of the oscillating circuit varies with a dielectric constant being present in the magnetic field of the electromagnetic device. Alternatively, the electromagnetic device may form an integral part of an electronic circuit being capable of providing pulses to the electromagnetic device. In this situation the type of medicament is determined by analyzing a pulse response signal from the electromagnetic device. The present invention further relates to an associated method for distinguishing different types of insulin, and to a method for determining an amount of medicament in a cartridge.
U.S. Pat. No. 5,782,814 discloses an apparatus for determining and recording a dose of an agent delivered with a syringe. The syringe has a barrel for holding the agent and a plunger movably positioned in the barrel for expelling the agent. The plunger includes a magnetically responsive element, such as an iron core. The apparatus suggested in U.S. Pat. No. 5,782,814 has a receptacle for receiving the syringe for dose measurement. An inductive element is positioned coaxially to the receptacle to produce a magnetic field. When the syringe is placed in the receptacle, the strength of the magnetic field varies in dependence upon the position of the plunger in the barrel. Thus, the strength of the magnetic field is indicative of the axial position of the plunger, and therefore indicative of a remaining amount of agent in the syringe. The magnetic field induces a voltage in a conducting loop. A voltage meter is connected to the conducting loop to measure the induced voltage which is indicative of the axial position of the plunger. A microprocessor is operatively connected to the voltage meter in order to calculate the remaining amount of agent from the induced voltage. A recorder, such as a digital memory unit, records the calculated amount of agent.
The apparatus suggested in U.S. Pat. No. 5,782,814 is purely intended for determining an amount of agent in a syringe, or alternative, determining an amount of agent delivered by a syringe.
A paper by Insuk Yu, “Electrodeless measurement of RF dielectric constant and loss” published in Meas. Sci. Technol. 4 (1993) 344-348 discloses a method by which liquids having different dielectric constants can be distinguished. The method of distinguishing liquids having different dielectric constants implies that the liquids are positioned in a magnetic field of a coil which forms part of an oscillating circuit. Upon positioning a sample which in this case is a liquid having a given dielectric constant the oscillating condition and Q-factor of the oscillating circuit is changed. This change depends on the dielectric constant of the liquid positioned in the magnetic field of the coil.
There is in the above-mentioned paper by Insuk Yu no mentioning of an appliance of the method in connection with distinguishing various types of medicament, such as insulin. Thus, there is in the above-mentioned paper no mentioning or hint in a direction of implementing the method in medication delivery devices in general, such as in for example insulin delivery devices.
U.S. Pat. No. 6,068,615 discloses various ways of measuring quantities of insulin in traditional syringes. In FIG. 2 of U.S. Pat. No. 6,068,615 a measuring apparatus (120) adapted to receive a traditional syringe (80) is disclosed. An inductor (100) is arranged around the syringe (80) when the syringe (80) is positioned in the measuring apparatus (120). Thus, in order to determine the quantity of insulin in the syringe an, in relation to the syringe, external measuring apparatus (120) is required. FIGS. 3 and 4 of U.S. Pat. No. 6,068,615 are concerned with traditional syringes where insulin is filled into chambers (92) of the syringes. Thus, the syringes (480) and (580) of FIGS. 3 and 4 of U.S. Pat. No. 6,068,615 are certainly not adapted to receive self-contained insulin containing cartridges.
WO 2006/021295 relates to an arrangement for determining the filling level of a substance in an ampoule. The arrangement comprises at least two electrodes between which the substance can be introduced. WO 2006/021295 further relates to a method for determining the filling level of a substance in an ampoule comprising at least two electrodes, whereby the filling level is determined by measuring the capacity of at least one capacitor involving the dielectric constant of the substance and the two electrodes between which the substance is positioned. Thus, WO 2006/021295 relates to an arrangement and a method for determining a substance level or quantity by capacitive means.
US 2002/188259 relates in general to product authentication by way of identification and certification of the origin or manufacturer of medical supplies, components etc. FIG. 1 of US 2002/188259 shows an RFID tag attached to a thin backing of for example self-adhesive paper. The RFID tag consists of a miniature integrated circuit and an antenna. A conductive loop of for example conductive ink or fine breakable conducting wire such as copper, is deposited on the backing and is in electrical connection to the integrated circuit via conductive traces and pads. The RFID tag allows identification of the medical supply to which the thin backing including the RFID tag is attached.
WO 2005/111961 also relates to an RFID tag attached to a thin backing. Also here the RFID tag involves a miniature integrated circuit electrically coupled to an antenna.
There are in US 2002/188259 and WO 2005/111961 no information as to the generation of magnetic fields for determining a type of medication or an amount of medicament.
WO 01/56635 relates to a substance containing container having a recognition element associated therewith. WO 01/56635 further relates to a sensor element adapted to read information out of or inscribe information into the recognition element. Similar to US 2002/188259 and WO 2005/111961 there is in WO 01/56635 no information as to the generation of magnetic fields for determining a type of medication or an amount of medicament.
It is an object of the present invention to provide an arrangement incorporated into a hand-held medication delivery device, a cartridge or similar device, the arrangement being capable of distinguishing liquids or medicaments, such as insulin, having different dielectric constants.
The above-mentioned object is complied with by providing, in a first aspect, a hand-held medication delivery device adapted to expel set doses of medicament into for example the body of a patient, the medication delivery device comprising a cartridge compartment adapted to receive and hold a medicament containing cartridge, the cartridge compartment comprising an electromagnetic device adapted to generate a magnetic field having a spatial overlap with at least part of a medicament in a cartridge positioned in the cartridge compartment, the electromagnetic device forming part of an electronic circuit adapted to oscillate at a predetermined resonance frequency or alternatively, forming part of an electronic circuit being capable of generating and providing pulses to the electromagnetic device. The resonance frequency of the electronic circuit may be controlled by an oscillating crystal or a microprocessor. The medicament containing cartridge may have substantially rigid outer sidewalls or it may have flexible outer sidewalls thus forming a cartridge with varying outer dimensions in combination with a flexible shape.
The medication delivery device according to the first aspect of the present invention may be a manual, a semi-automatic, an automatic or a motor driven medication delivery device for injecting or delivering a medicament, such as insulin, into a patient. By manual medication delivery device is meant a device where the medicament is expelled from the device purely by means of a force provided by the user of the manual medication delivery device. By semi-automatic and automatic is meant that the energy necessary to expel the medicament from the device is at least partly accumulated in the device. As an example such energy may be accumulated or stored in a resilient member, such as in a torsion or axial spring. Finally, the medication delivery device may be a motor-based device where the medicament is expelled from the device by use of an electric motor.
As used herein, the term medicament is meant to encompass any medicament-containing flowable medicine capable of being passed through a delivery means, such as a hollow needle, in a controlled manner. Thus, the term medicament covers liquid solutions, gels or fine suspension. Representative medicaments include pharmaceuticals such as peptides, proteins (e.g. insulin, insulin analogues and C-peptide), and hormones, biologically derived or active agents, hormonal and gene based agents, nutritional formulas and other substances in both solid (dispensed) or liquid form.
The electromagnetic device may comprise a coil of wound wire or alternatively, another electromagnetic device capable of generating a magnetic field. Such other device may be an electrically conductive path arranged, for example, on a printed circuit board, such as a flex-print. In the following the electromagnetic device will be described with reference to a coil of wound wire but it should be understood that the present invention is not limited to such a device. The wound wire may be arranged in such a manner that it forms an essentially helical path around the cartridge when said cartridge is positioned in the cartridge compartment. The essentially helical path of wound wire may define a centre axis, said centre axis essentially coinciding with a centre axis of the cartridge when said cartridge is positioned in the cartridge compartment of the medication delivery device. The length of the essentially helical path in a direction parallel to its centre axis substantially may equal a length of a medicament containing container of the cartridge. The term medicament containing container is here to be understood as that part of the cartridge which is capable of containing a medicament.
The electronic circuit may comprise one or more capacitors adapted to exchange energy with the electromagnetic device.
In a second aspect, the present invention relates to a cartridge for a medication delivery device, the cartridge comprising a medicament containing container comprising an electromagnetic device adapted to generate a magnetic field having a spatial overlap with at least part of a medicament in the medicament containing container, the electromagnetic device being connectable to an electronic circuit adapted to oscillate at a predetermined resonance frequency or alternatively, connectable to an electronic circuit being capable of generating and providing pulses to the electromagnetic device. Again, the resonance frequency of the electronic circuit may be controlled by an oscillating crystal or a microprocessor. The cartridge may have substantially rigid outer sidewalls similar to a traditionally, cylindrically shaped cartridge or it may have flexible outer sidewalls thus forming a cartridge with varying outer dimensions in combination with a flexible shape.
Again, the term medicament containing container is to be understood as that part of the cartridge which is capable of containing a medicament. As with the medication delivery device the electromagnetic device may comprise a coil of wound wire shaped as an essentially helical path. The essentially helical path of wound wire may define a centre axis, said centre axis essentially coinciding with a centre axis of the medicament containing container. The length of the essentially helical path in a direction parallel to its centre axis substantially may equal a length of the medicament containing container.
The wound wire forming the essentially helical path may be embedded into one or more sidewall portions of the medicament containing container. These sidewall portions may be essentially cylindrically shaped. Alternatively, the wound wire forming the essentially helical path may be manufactured separately and thereafter arranged on one or more exterior sidewall portions of the medicament containing container.
The electronic circuit, including one or more capacitors adapted to exchange energy with the electromagnetic device, may form an integral part of the cartridge.
In a third aspect, the present invention relates to a label adapted to be arranged on an exterior surface portion of a medicament containing container of a cartridge for a medication delivery device, the label comprising an integrated electromagnetic device adapted to generate a magnetic field having a spatial overlap with at least part of a medicament in the medicament containing container when the label is arranged on the exterior surface portion of the medicament containing container, the electromagnetic device being connectable to an electronic circuit adapted to oscillate at a predetermined resonance frequency or alternatively, connectable to an electronic circuit being capable of generating and providing pulses to the electromagnetic device. The resonance frequency of the electronic circuit may be controlled by an oscillating crystal or a microprocessor.
The label may be implemented as a flexible, self-adhesive label which is adapted to follow contours of the exterior surface portion of the medicament containing container. The electromagnetic device may form an essentially helical-shaped coil when the label is arranged on the exterior surface portion of the medicament containing container. The essentially helical-shaped coil may define a centre axis, said centre axis essentially coinciding with a centre axis of the medicament containing container when the label is arranged on the exterior surface portion of the medicament containing container. The length of the essentially helical-shaped coil in a direction parallel to its centre axis substantially may equal a length of the medicament containing container.
The electronic circuit may form an integral part of the label. In addition, the electronic circuit may comprise a capacitor adapted to exchange energy with the electromagnetic device.
In a fourth aspect, the present invention relates to a method for identifying a type of medicament in a cartridge for insertion into a cartridge compartment of a medication delivery device, the method comprising the steps of
In a fifth aspect, the present invention relates to a method for determining an amount of medicament in a cartridge for insertion into a cartridge compartment of a medication delivery device, the method comprising the steps of
Thus, according to the fourth and fifth aspects of the present invention a type and an amount of a medicament in a cartridge may be determined from a modified resonance frequency by comparing this modified resonance frequency with pre-stored frequency values, such as frequency values of an electronic look-up table.
In case the modified resonance frequency matches, within pre-specified tolerances, a value in the look-up table the type of medicament in the cartridge may be unambiguously determined in that each value of the look-up table is associated with a given type of medicament in a completely full cartridge. However, the type of medicament in the cartridge may also be unambiguously determined in case the cartridge is only partly filled. When the type of medicament has been determined measurements of the modified resonance frequency may be applied to determine a remaining amount of medicament in the cartridge. If a match between a modified resonance frequency and the look-up table, within pre-specified tolerances, is reached the remaining amount of medicament in the cartridge may be unambiguously determined.
The electronic circuit of the fourth and fifth aspects may comprise an inductor operatively coupled to a capacitor. Alternatively, the resonance frequency of the electronic circuit may be controlled by an oscillating crystal or a microprocessor.
In a sixth aspect, the present invention relates to a method for identifying a type of medicament in a cartridge for insertion into a cartridge compartment of a medication delivery device, the method comprising the steps of
In a seventh aspect, the present invention relates to a method for determining an amount of medicament in a cartridge for insertion into a cartridge compartment of a medication delivery device, the method comprising the steps of
The present invention will now be explained in further details with reference to the accompanying figures, wherein
While the invention is susceptible to various modifications and alternative forms, specific embodiments have been shown by way of example in the drawings and will be described in detail herein. It should be understood, however, that the invention is not intended to be limited to the particular forms disclosed. Rather, the invention is to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the invention as defined by the appended claims.
In its most general aspect the present invention relates to an arrangement for contact free determination of a type of medicament in a cartridge. Thus, by incorporating the arrangement according to the present invention in a cartridge compartment of a medication delivery device, or by incorporating the arrangement according to the present invention in a medicament containing cartridge various types of medicaments can be distinguished from each other. Thus, in case of an insulin delivery device the type of insulin present in the device can be determined and thereby communicated to the patient using the insulin delivery device. In fact, an insulin delivery device may be pre-programmed only to accept certain types of insulin. In case a wrong type of insulin is inserted into the insulin delivery device an alarm signal may be generated informing the patient that he or she has inserted a wrong type of insulin in the device. In addition, means for preventing the insulin delivery device from being operable in case a wrong type of insulin is inserted into the device can be provided.
As already mentioned the medication delivery device can be a manual, a semi-automatic, an automatic or a motor driven medication delivery device for injecting or delivering a medicament, such as insulin, into a patient. By manual medication delivery device is meant a device where the medicament is expelled from the device purely by means of a force provided by the user of the manual medication delivery device. By semi-automatic and automatic is meant that the energy necessary to expel the medicament from the device is at least part accumulated in the device. As an example such energy may be accumulated or stored in a resilient member, such as in a torsion or axial spring. Finally, the medication delivery device may be a motor-based device where the medicament is expelled from the device by use of an electric motor.
The helical-shaped inductor 5 generates a magnetic field in the axial direction of the cartridge 4. In principle, the inductor 5 can also be oriented differently, i.e. generating a magnetic field in a different direction relative to the cartridge.
The resonance frequency of the oscillating circuit may in principle be chosen arbitrarily. In the present invention a so-called Colpitts-oscillator oscillating at a frequency around 19 MHz and a more frequency stable oscillator oscillating a frequency around 7 MHz have been applied. Circuit diagrams of these oscillators are shown in
The oscillator can be arranged in various manners. For example, the complete circuit including the inductor can be positioned within the medication delivery device. However, the oscillator can also be split between the medicament containing cartridge and the medicament delivery device in that the inductor can be arranged on or integrated with the cartridge whereas the rest of the oscillator is arranged within the medication delivery device. Obviously, an electrical connection between the inductor and the rest of the oscillator must be provided. Alternative, the complete oscillator can be arranged on or integrated with the medicament containing cartridge.
It should be noted that other principles than shifts in resonance frequencies may be applied to measure characteristics of a medicament positioned in a magnetic field. For example, an electronic circuit adapted to generate and provide one or more electric pulses to the inductor is also applicable. In this situation the type of medicament will be determined by analyzing the pulse response signal from the inductor when the medicament is positioned in the inductor and one or more electric pulses are provided to the inductor.
As seen in
| Number | Date | Country | Kind |
|---|---|---|---|
| 06014117.3 | Jul 2006 | EP | regional |
| Filing Document | Filing Date | Country | Kind | 371c Date |
|---|---|---|---|---|
| PCT/EP07/56418 | 6/27/2007 | WO | 00 | 4/21/2009 |
