Patent Publication Number: US-9851360-B2

Title: Self contained in-vitro diagnostic device

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is a Divisional application of U.S. patent application Ser. No. 13/069,348 filed Mar. 22, 2011, issued as U.S. Pat. No. 8,673,214 on Mar. 18, 2014 which claims the benefit of U.S. Provisional Application No. 61/316,002, filed on Mar. 22, 2010, the entireties of which is hereby incorporated by reference. 
    
    
     FIELD OF THE INVENTION 
     The present invention relates to a self-contained in-vitro diagnostic device, and specifically to a disposable diagnostic device that has fixed sensors. 
     BACKGROUND OF THE INVENTION 
     Diabetes is a disease in which the body does not produce or properly use insulin. Insulin is a hormone that is needed to convert sugar, starches and other food into glucose, which is the fuel cells need for on-going activity. Published studies indicate that at least 7% of the US population has diabetes, and about 70% of those with diabetes have been diagnosed. About 5-10% of all diabetics have Type I diabetes in which the pancreatic cells that produce insulin have been destroyed. Thus, there are no cells to produce the chemical that produces insulin. Type I diabetes is treated by supplying insulin by injection or pump. The balance of those with diabetes have Type II diabetes in which pancreatic cells produce insulin, but other cells in the body do not use insulin well to convert food into glucose. Type II diabetes is treated by diet, exercise, oral medications, insulin, or a combination thereof. 
     While diabetes cannot yet be cured, it can be controlled. If it is not controlled, complications result. For example, adults with diabetes have heart disease rates about 2 to 4 times higher than adults without diabetes. The risk for stroke is 2 to 4 times higher among people with diabetes. Diabetes is the leading cause of new cases of blindness among adults aged 20-74 and the leading cause of kidney failure. About 60-70% of people with diabetes have mild to severe forms of nervous system damage. The result of such damage includes impaired sensation or pain in the feet or hands, which may eventually result in amputation of the limb. In addition, people with diabetes are more susceptible to many other illnesses and, once they acquire these illnesses, often have worse prognoses than non-diabetics. 
     As it stands, if an adult or child would like to know if they are at risk for diabetes, they are required to contact their physician, schedule an appointment, subject themselves to blood tests and then report back to their physician when the results are obtained. This process can be both an expensive and time consuming process for the patient. Due to the cost of both time and money, many individuals forgo proper testing and are therefore not properly diagnosed. Further, this process is made even more difficult for those without primary care physicians or medical insurance to pay for the appointments and testing that is required. Therefore, the remains a need for a self-contained in-vitro diagnostic device that is inexpensive, can be used easily at the home of the patient and provides for a one-time diagnostic check-up. 
     To control diabetes, it is necessary to monitor the level of glucose in the blood. The frequency of measurement varies from patient to patient, depending on a number of factors including the severity of the disease, type of diabetes, level of physical activity, eating habits, and other health issues. For patients with diabetes, it is often necessary to determine the glucose level in blood several times a day. Consistently taking readings help patients manage their glucose levels better, thereby improving insulin and other therapies and helping to prevent complications. 
     A common method of blood glucose self-monitoring is to prick a finger or other area to release capillary blood, absorb a minute amount of blood onto a test strip, and insert the test strip into a monitor to measure the amount of glucose in the blood. In particular many devices allow for self assessment of blood glucose for diabetes patients. Many of these devices are small portable diagnostic monitors that use replaceable single-use test strips. By placing a very small volume of blood on such a single use test strip, an electrochemical reaction converts the blood glucose into a small electric current that relatively easily can be converted into a blood glucose value/level within second. These devices further require that the user enter calibration data specific to the test strips being used. Since the prior art devices all require that test strips be entered for each single use, a user is required to enter calibration data each time a new set of test strips is to be used with the device. 
     Although the current devices typically meet the requirements for disease management of chronic patients, another set of requirements apply in a screening setting, whether for diabetes, high cholesterol, or other physiological conditions. The cost of the device hardware, distribution, training, calibration and data feedback requirements all make the current devices non-practical. Screening therefore typically requires a patient to go to a hospital where a blood sample is taken and the blood sample sent to a laboratory for analysis and testing. Further, it is often desired to have a fasting blood glucose level/value as well as a value after intake of a certain amount of simple sugars, which add timing constraints to the already complicated process. Therefore, there is a need for a device that is economical and self-contained and which allows for a quick screen test in a patient&#39;s home environment where the results can be effectively and securely transmitted to a centralized location for diagnosis. 
     SUMMARY OF THE INVENTION 
     One aspect of the present invention is a portable apparatus for measuring a glucose level of a user comprising: a card-like member; a processor within the card-like member; at least one glucose sensor comprising a reagent, the glucose sensor generating a signal indicative of a measured glucose level upon application of a blood sample to the glucose sensor, wherein the glucose sensor is fixed to the card-like member and operably coupled to the processor; and at least one cover alterable between a first position in which the glucose sensor is covered and a second position in which the glucose sensor is exposed for use. 
     Another aspect of the present invention is a portable apparatus for measuring a glucose level of a user comprising: a card-like member; a processor within the card-like member; at least one glucose sensor comprising a reagent, the glucose sensor generating a signal indicative of a measured glucose level upon application of a blood sample to the glucose sensor, wherein the glucose sensor is fixed to the card-like member and operably coupled to the processor; and a memory device within the card-like member and operably coupled to the processor the memory device comprising pre-stored calibration data unique to the glucose sensor. 
     In yet another aspect of the present invention is a portable apparatus for measuring a physiological condition comprising: a card-like member; a processor within the card-like member; at least one sensor comprising a reagent, the sensor generating a signal indicative of a measured physiological parameter upon application of a blood sample to the sensor, wherein the sensor is fixed to the card-like member and operably coupled to the processor; and at least one cover alterable between a first position in which the sensor is covered and a second position in which the sensor is exposed for use. 
     Further areas of applicability of the present invention will become apparent from the detailed description provided hereinafter. It should be understood that the detailed description and specific examples, while indicating the preferred embodiment of the invention, are intended for purposes of illustration only and are not intended to limit the scope of the invention. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The present invention will become more fully understood from the detailed description and the accompanying drawings, wherein: 
         FIG. 1  is a schematic of a system according to one embodiment of the present invention; 
         FIG. 2  is a schematic of a device according to one embodiment of the present invention; 
         FIG. 3  is a perspective view of the device of  FIG. 2  with the covers disposed on top of the sensors according to one embodiment of the present invention. 
         FIG. 4  is a perspective view of the device of  FIG. 2  wherein one sensor is illustrated with a cover disposed on top, another sensor is illustrated with a cover in a second position, and yet another sensor with the cover removed completely according to another embodiment of the present invention. 
         FIG. 5  is a perspective view of the device of  FIG. 2  wherein the calibration sensor which is inaccessible to the user is illustrated according to another embodiment of the present invention. 
         FIG. 6  is a perspective view of another embodiment of the device of the present invention. 
         FIG. 7  is a method of using the device of  FIG. 2  according to one embodiment of the present invention. 
     
    
    
     DETAILED DESCRIPTION 
     The following description of the preferred embodiment(s) is merely exemplary in nature and is in no way intended to limit the invention, its application, or uses. 
     The description of illustrative embodiments according to principles of the present invention is intended to be read in connection with the accompanying drawings, which are to be considered part of the entire written description. In the description of embodiments of the invention disclosed herein, any reference to direction or orientation is merely intended for convenience of description and is not intended in any way to limit the scope of the present invention. Relative terms such as “lower,” “upper,” “horizontal,” “vertical,” “above,” “below,” “up,” “down,” “top” and “bottom” as well as derivative thereof (e.g., “horizontally,” “downwardly,” “upwardly,” etc.) should be construed to refer to the orientation as then described or as shown in the drawing under discussion. These relative terms are for convenience of description only and do not require that the apparatus be constructed or operated in a particular orientation unless explicitly indicated as such. Terms such as “attached,” “affixed,” “connected,” “coupled,” “interconnected,” and similar refer to a relationship wherein structures are secured or attached to one another either directly or indirectly through intervening structures, as well as both movable or rigid attachments or relationships, unless expressly described otherwise. Moreover, the features and benefits of the invention are illustrated by reference to the exemplified embodiments. Accordingly, the invention expressly should not be limited to such exemplary embodiments illustrating some possible non-limiting combination of features that may exist alone or in other combinations of features; the scope of the invention being defined by the claims appended hereto. 
     In the description of embodiments of the invention disclosed herein, any reference to direction or orientation is merely intended for convenience of description and is not intended in any way to limit the scope of the present invention. Moreover, the features and benefits of the invention are illustrated by reference to exemplified embodiments. Accordingly, the invention expressly should not be limited to such exemplified embodiments illustrating some possible but non-limiting combination of features that may be provided alone or in other combinations of features; the scope of the invention being defined by the claims appended hereto. 
     Referring to  FIG. 1 , a schematic of a system  1000  according to an embodiment of the present invention is illustrated. A device  100  obtains a sample from a user, generates a signal relating to a calculated physiological parameter, calculates an actual physiological value relating to the received sample and transmits the actual physiological value and corresponding information to an external device. The external device can be a personal computer  901 , a mobile communication device  902  or a remote server  903 . The transmission of the actual physiological value can be by means of a wireless communication device located within the device or a wired connection to the external device. In one embodiment, device  100  may simply store the actual physiological value and corresponding information until the device  100  is sent to a centralized data processing and diagnostics site where the device  100  is scanned and the information retrieved. In an alternate embodiment, the physiological parameter may be wirelessly transmitted to a personal computer  901  or mobile communication device  902  at the location of the user, and then transmitted through the internet  904  to a remote server  903  for view on a personal computer  905 , such as a personal computer located at a physician or doctor&#39;s office. 
     Referring to  FIG. 2 , a schematic of the device  100  according to an embodiment of the present invention is illustrated. The device comprises a processor  101 , a power supply  103 , a memory unit  104 , a wireless communication unit  105 , a temperature sensor  106 , at least one test site  200  (comprising at least one sensor  201 ) and at least one indication device  300 . 
     In the exemplified embodiment, the processor  101  comprises signal-conditional means, data processing means, data acquisition means, an analog-to-digital converter (A/D)  102 , and an internal clock  107 . The processor  101  is operably coupled to and configured to control the interaction of the power supply  103 , the memory unit  104 , the wireless communication unit  105 , the temperature sensor  106 , the at least one test site  200 , the at least one sensor  201  and the at least one indication device  300 . Specifically, the processor  101  must be configured to the specific properties of the at least one sensor  201  configured within the device  100 . The clock  107  is configured to provide time-keeping means to allow each measurement of the device  100  to be time-stamped and stored in the memory unit  104 . The power supply  103  is operably coupled to and configured to supply power to the processor  101 , the memory unit  104 , the wireless communication unit  105 , the temperature sensor  106 , the at least one test site  200 , the at least one sensor  201  and the at least one indication device  300 . The memory unit  104  is operably coupled to the processor  101  and configured to store data. In one embodiment, the memory unit  104  may be a non-volatile memory unit. 
     The wireless communication unit  105  is operably coupled to and configured to transmit data wirelessly to an external device. In one embodiment, the wireless communication device  105  comprises an integrated planar antenna. Further, in one embodiment, the wireless communication device  105  uses radio frequency identification (RFID) to communication with the external device. The wireless communication device  105  may use active, passive, or semi-passive RFID technologies. In alternate embodiments, the wireless communication device  105  may be a Bluetooth® enabled device or Zigbee® enabled device. Further, in other alternate embodiments, the wireless communication device  105  may be a device that uses any other non-proprietary wireless protocol for wireless communication. It should be noted that in alternate embodiments, the wireless communication device may be omitted and the device may comprise various ports for wired connections to the external device. Since the information being transmitted by the wireless communication device  105  may be confidential, optional cryptographic operations can be performed prior to data exchange, so that only a legitimate receiver can decrypt and verify the data retrieved from the device  100 . 
     As noted above, the present invention provides for at least one temperature sensor  106  (e.g., a thermistor, thermometer, or thermocouple device) which is used to measure temperature at the site of the sensor  201 , along with the ambient temperature. As with any chemical sensing method, transient changes in temperature during or between measurement cycles can alter background signal, reaction constants and/or diffusion coefficients. Accordingly, the temperature sensor  106  is used to monitor changes in temperature over time. A maximum temperature change over time threshold value can be used to invalidate a measurement of a sensor  201 . Such a threshold value can, of course, be set at any objective level, which in turn can be empirically determined depending upon the sensor  201  used, how the temperature measurement is obtained, and the physiological parameter being detected. In the illustrated embodiment of  FIGS. 3 and 4 , the design of the device  100  gives a reasonable isothermal environment and the temperature sensor  105  may provide a signal proportional to the temperature at the sensor  201  site to the processor  101 . 
     Absolute temperature threshold criteria can also be detected by the temperature sensor  106 , wherein detection of high and/or low temperature extremes can be used in a data screen to invalidate a measurement by a sensor  201 . The temperature sensor  106 , for example, may provide a voltage proportional to the temperature to the A/D converter  102  of the processor  101  of the device  100 , which can then make a determination as to whether the temperature of the testing environment is within predetermined thresholds, and signal an indication device  300  if accuracy would be negatively affected. 
     Referring to  FIGS. 3 and 4 , a device  100  according to one embodiment of the present invention is illustrated. In the exemplified embodiment, the device  100  comprises is a body  120  that is a thin, flat article having opposing planar surfaces that are substantially parallel to each other (referred to herein as a “planar design”). In one embodiment, the body  120  is a card-like member that has a planar design. In alternate embodiments, the surfaces of the device  100  may be contoured or curved, and therefore do not have to be substantially parallel to each other. In one embodiment where the device is of a planar design, one side is perfectly flat and allows for traditional screen-printing techniques to be used to apply the elements/components of the sensors  201 . Therefore, the sensors  201  are all configured in the same level and on the same substrate that holds the biosensor chemistry, thereby eliminating all interconnections. 
     As shown in  FIGS. 3 and 4 , the device  100  comprises three test sites  200 , each test site  200  having a corresponding cover  400 . It should be noted that the invention is not limited to the number or type of test sites  200  used in the device  100 . Further, in alternate embodiments, the device  100  may have more or less covers  400  than test sites  200 . 
     As illustrated in  FIGS. 3 and 4 , each test site  200  has a corresponding cover  400  that is secured and disposed on top of the test site  200 . The cover  400  comprises a tab  401  and at least one securing piece  402 . The cover  400  is configured so that a user may lift on the tab  401  to remove the cover  400  thereby exposing the underlying sensor  201 . Further, in the illustrated embodiment, the side of the cover  400  opposing the tab  401  comprises the securing pieces  402 . The securing pieces are configured to prevent the cover  400  from being completely removed from the device  100 . Therefore, the cover  400  may be configured in and in-between two positions: a first position (shown in  FIG. 3 ) whereby the cover  400  is covering the test site  200  and protecting the sensor  201  from moisture and contamination from the outside environment, and a second position (shown in  FIG. 4 ) wherein the cover  400  is removed from the test site  200  thereby exposing the sensor  201  to the outside environment. 
     In the exemplified embodiment, the cover  400  is operably configurable between the first and second positions more than one time, so that the cover  400  may first cover the test site  200 , then be configured to the second position to expose the sensor  201  for the application of a sample, and then be configured to re-cover the test site  200  so that the sample is contained within the sensor  201 . The invention, however, is not so limited and in alternate embodiments the securing pieces  402  may be omitted so that the cover  400  may be completely removable from the device  100 . In one embodiment, the cover  400  is a removable seal, and the removable seal is a piece of removable foil. The invention, however, is not so limited and the cover  400  may comprise a hinged structure, a removable seal, or a combination thereof. In embodiments where the cover  400  comprises both a hinged structure and a removable seal, the removable seal is disposed between the sensor and the hinged structure. Further, in alternate embodiments, the tab  401  may be omitted. 
     In one embodiment, when the cover  400  is disposed on top of a test site  200  (in the first position), the cover  400  may be secured by an adhesive (not shown) that is located either on the cover  400  and/or on a corresponding portion of the body  120  of the device  100 . The adhesive preferably creates a moisture tight seal when the cover  400  is in the first position. Further, the adhesive is preferably designed so that the cover  400  may be re-oriented in the first position after being oriented in the second position and still maintain a moisture tight seal over the sensor  201 . In an alternate embodiment, the cover  400  may be configured to fully seal the entire test site  200  in an air tight and water tight manner. 
     In an alternate embodiment, the cover  400  and body  120  may comprise interlocking interfaces that are configured to secure the cover  400  to the body  120  when the cover is in the first position, and allow the cover to be configurable between the first and second positions as described above. 
     Further, in some embodiments, the device  100  further comprises a small amount of desiccant that is added adjacent to each test site  200  to absorb any moisture that could potential seep into the sensor  201 . 
     As described in more detail below,  FIG. 3  illustrates an embodiment of the device  100  of the present invention that comprises three test sites  200 , each test site  200  being covered by a corresponding cover  400 .  FIG. 4  illustrates an embodiment of the device  100  of the present invention that comprises three test sites  200 , whereby the first test site  200  has its cover  400  in the second position so that the sensor  201  of the test site  200  is exposed, the second test site  200  is covered by a cover  400  that is in the first position, and the third test site  200  has its cover  400  completely removed so that its test site  200  and sensor  201  are completely exposed. It should be noted that the various states of the covers  400  and test sites  200  of device  100  of  FIG. 4  are illustrated to aid in the discussion of the device  100  and its components, and are in no way limited of the invention. 
     Referring to  FIGS. 3-4 , the device  100  may comprise one or more test sites  200 , each test site  200  comprising a sensor  201  and at least one sensing pad  220 . The sensor  201  comprises a cavity  205  and a reagent  210 , the reagent  210  being located substantially within the cavity  205 . In one embodiment, the sensor  201  is located within a depression on the test site  200 . Further, in some embodiments, the sensor  201  is embedded within and affixed to the device  100 . Therefore, in some embodiments, the sensors  201  cannot be removed from the device  100 . The reagent  210  is configured to alter its properties to enable the sensor  201  to detect and measure a physiological parameter of a sample when the sample is placed within the cavity  205 . 
     It should be noted that the sensor  201  is generically illustrated as a circular shaped area. The invention, however, is not so limited and in alternate embodiments the sensor  201  may be of different sizes and shapes. Further, it should be noted that the cavity  205  is also generically illustrated, and in alternate embodiments the cavity  205  may be of different sizes and shapes. Moreover, it should be noted that the reagent  210  is also generically illustrated as a square, and in alternate embodiments the reagent  210  may be of different sizes and shapes. Further, in alternate embodiments the cavity  205  may be omitted. 
     As noted above, each sensor  201  is configured to measure a physiological parameter of a sample when the sample is placed in or on the sensor  201 . A physiological parameter may be a glucose level/concentration, a cholesterol level/concentration, a blood urea nitrogen (BUN) level/concentration or a creatinine level/concentration. The invention, however, is not so limited and the physiological parameter may be any other value or characteristic relating to an organism&#39;s health or function. In one embodiment, the sample is a mammalian blood sample. The invention, however, is not so limited and any sample that comprises a trace of a physiological parameter may be used. For example, in an embodiment where the sensor  201  is designed to measure a glucose level, the reagent  210  may be glucose oxidase, glucose dehydrogenase/pyrroloquinolinequinone, dehydrogenase/nicotinamide-adenine dinucleotide, dehydrogenase/flavin-adenine dinucleotide, or any other compound capable of detecting glucose in a sample. 
     The sensing pad  220  of the test site  200  is configured to detect when the cover  400  corresponding to the test site  200  is lifted or removed from the first (covered) position and into the second (exposed) position. When the cover  400  of a test site  200  is lifted, the sensing pad  220  sends a signal to the processor  101  of the device  100  and initializes the measurement and sensing processes of the sensor  201  and processor  101 . Therefore, when a sample is placed on the sensor  201 , the measurement and sensing processes of the sensor  201  and processor  101  are enabled and can detect the presence of the physiological parameter of the sample. As discussed in more detail below, after the sensor  201  senses and measures the physiological parameters of the sample placed thereon, the sensor  201  transmits a signal indicative of the measures physiological parameter to the processor  101  and memory unit  104 . 
     Further, when the cover  400  is lifted, an indication device  300  corresponding to that particular sensor  201  is also initialized. In the exemplified embodiment, the indication device  300  is an LED that is illuminated (either flashing or a steady “on” state) when the cover  400  of the corresponding test site  200  is configured to the second position. The invention, however, is not so limited and in alternate embodiments the indication device  300  may be any other device that can be used to signal information to the user. In one embodiment, after the measurement and sensing processes are completed on the sample, the indication device  300  alters its state (e.g. going from a flashing state to a steady “on” state) to indicated that the sensing and measurement processes are complete. Thereafter, in one embodiment, the user may reconfigure the cover  400  back to the first position so that the sensor  201  and sample are covered and unexposed, and the indication device  300  may turn off after a pre-determined time period to save power. Furthermore, in one embodiment, if the device  100  is turned on again, the indication device  300  corresponding to the used testing site  200  may indicate that the site has already been used (e.g. lighting up in a different color or not lighting up at all). 
     Depending on the requirements of the particular application of the device  100 , a plurality of sensors  201  may be configured on a device  100 . The sensors  201  can either be of the same type (meaning they measure the same physiological parameter) or comprise various different reagents  210  to allow a quantitative analysis of more than one physiological parameter using one device  100 . In alternate embodiments, the sensors  201  may be biochemical sensors and electrochemical biosensors for detecting a physiological parameter of a sample. In one embodiment, the sensor  201  is a biochemical sensor or an electrochemical biosensor and comprises at least two electrodes and a biochemically active material (reagent) working in a voltammetric setting. 
     In another embodiment, the sensor  201  and reagent  210  comprise physiological measuring technology that is based upon the well known, mature, reliable, accurate, quick response, non-continuous, test strip based measurement technologies which are sometimes referred to as episodic or intermittent monitoring technologies. Test strip based monitoring systems are considered invasive, i.e. systems which require a capillary blood sample to estimate the individual&#39;s blood glucose concentration. Such samples are normally obtained by lancing a finger tip or an approved alternate test site to obtain such a capillary blood sample. Further, these systems are characterized by an electrochemical measurement based upon a reaction with blood glucose that generates an electrical current when read by corresponding electronics of the sensor  201 , whose magnitude corresponds to the physiological (e.g. glucose, cholesterol, etc.) concentration of the test sample. In such a system, a user only needs to supply an adequate sample to the reagent  210  within the sensor cavity  205  and wait for the processor  100  to calculate a reading. 
     As noted above, the processor  101  should be configured to the specific properties of the sensors  201  contained therewith prior to the application of a sample and a measurement of a physiological parameter. Further, since the sensors  201  of the present invention are affixed to or embedded in the device  100 , the processor  101  of the device may be pre-calibrated to the specific properties of the specific sensors  201  contained within prior to distribution to a user. It should be noted that during the manufacturing of physiological sensors, small discrepancies result in the properties of the sensors from one lot and sensors of a different lot. In particular, sensors of one manufacturing lot will usually have properties that vary from the properties of sensors of a different manufacturing. The specific properties that can vary include, but are not limited to, the specific concentration of reagent in the sensor, the volume and/or exposed area of the reagent in the sensor, and/or the volume of the cavity within the sensor (which ultimately varies the volume of the sample obtained for measurement). If the processor is configured to one sensor from one lot, and later a sensor from another lot is used within the device, then errors may result from the discrepancies in the specific properties of the sensor used compared to the sensor that the device was calibrated/configured for. Therefore, as with any device, the processor  101  of the present invention must be calibrated to the specific properties of the sensors  201  used by the device  100 . 
     As used herein, the same lot includes: (1) sensors that go through the same manufacturing process at the same time and in the same batch; (2) sensors that go through the same manufacturing process at substantially the same time but in different batches; and (3) sensors that go through the same manufacturing process at different times and in different batches. 
     In one embodiment, the processor  101  is pre-loaded with the specific properties of the sensors  201  contained therewith. Stated another way, the processor  101  of the device  100  comprises pre-stored calibration data that is unique to the specific sensors contained therein. Therefore, not only does the user not have to enter in any sort of specific calibration code (as required by many prior art devices), but there is also a reduced risk that the devices will be mis-calibrated since they are pre-calibrated prior to receipt by the user. 
     Referring to  FIG. 5 , the device  100  according to one embodiment of the present invention is illustrated. The device  100  is substantially similar to the devices of  FIGS. 4 and 5 , except the device  100  of  FIG. 5  further comprises a calibration sensor  600 . The calibration sensor  600  is substantially similar to and provided from the same lot as the other sensors  201  (not illustrated but provided under their respective covers  400 ) provided within the device  100 . In the exemplified embodiment, the calibration sensor  600  is not viewable or accessible to the user from the outside of the device  100 . Since the calibration sensor  600  is from the same lot as the other sensors  201 , the calibration sensor  600  has substantially the same specific properties as the other sensors  201  of the device  100 , and as a result can be used to pre-calibrate the device  100 . 
     In one embodiment, during the manufacturing of the device  100 , a test sample with a known physiological parameter (e.g. a known glucose level) is applied to the sensing element of the calibration sensor  600  and a test signal is generated and transmitted to the processor  101 . Since the physiological parameter of the test sample is known, when the processor  101  receives the test signal, the processor  101  can be calibrated for the specific properties of the calibration sensor  600 . Further, this test signal and calibration information may then be saved in the memory unit  104  so that accurate measurements are obtained when the other sensors  201  of the device  100  are later used. Also, since the remaining sensors  201  of the device  100  are from the same lot as the calibration sensor  600 , the processor is pre-configured for the specific properties of the sensors  201 . Further, since the pre-calibration process is done prior to distributing the device  100  to the user, the user is not required to do any calibration steps prior to using the device  100 . 
     In one embodiment, after the calibration sensor  600  is used for calibrating the processor  101  of the device  100 , the calibration sensor  600  may be configured so that it is unusable by the user. In one embodiment, the calibration sensor  600  may be configured so that it is unusable by the user by electrically disconnecting the calibration sensor  600  from the processor. In an alternate embodiment, the calibration sensor  600  may simply be inaccessible to the user by, for example, hiding the calibration sensor  600  under the body  120  of the device so not to be viewable by the user. 
     One method of calibrating the processor  101  of the present invention uses the slope data of a received current level over time when a test sample with a known physiological parameter (e.g. concentration) is applied to the calibration sensor  600 . When a test sample with a known physiological parameter (e.g. concentration) is applied to the calibration sensor  600 , an electric charge is created under an electrical bias. The current level of the electric charge depends on the physiological parameter (e.g. concentration). Since there is a substantially linear correlation between the current after a certain time and the physiological parameter (e.g. concentration), and since the physiological parameter (e.g. concentration) used on the calibration sensor  600  is known, any sort of deviation of the slope due to the specific properties of the sensors from a specific lot can be calculated and accounted for when using the other sensors  201 . The invention, however, is not so limited and in alternate embodiments other methods of calibrating the processor  101  may be used. 
     In one embodiment, the self-contained an integrated design of the device  100  allows for usage of low costs components as each channel in the voltammetric data acquisition system can be individually calibrated at the time of manufacturing. Therefore, deviations in voltage output and current measurement as well as individual variations in each sensor response can be stored in memory  104 . 
     In one alternate embodiment, the device  100  may further comprise an indication device  300  that indicated that the device  100  is unfit for use because the device  100  has exceeded its pre-determined shelf life. Such calculations can be accomplished by the clock  107  within the processor  101 , and thereby prevent invalid readings. 
     In one embodiment, the device  100  further comprises a button  500  (shown in  FIGS. 3 and 4 ). The button  500  is configured to allow the user to start and power up the device  100  and/or to turn off the device  100 . In an alternate embodiment, the device  100  may comprise a plurality of touch buttons allowing for user feedback at the time the measurement of a sensor  201  is taken. For example, the user can be asked to answer a question, the result of the question stored together with the measurement result of the sensor  201  in the memory unit  104 . In other alternate embodiments, the device  100  may further comprise a display screen to user interaction and/or feedback. 
     In other alternate embodiments, the device may further comprises other indication devices  300  (shown in  FIG. 3 ) that indicate other forms of information to the user (e.g. Temperature, Health Status, and/or Wireless Communication). In the exemplified embodiment, the indication devices  300  are LEDs that illuminated to convey information to the user. The invention, however, is not so limited and in alternate embodiments the indication devices  300  may be any other device that can be used to signal information to the user. For example, the indication device  300  may be associated with a temperature reading, whereby the indication device  300  lights up when the temperature reading is too high and/or too low. 
     Further, in one embodiment, the indication device  300  may be associated with a health status reading, whereby the indication device  300  lights up in one of a plurality of colors to indicate to the user whether the actual physiological level calculated by the processor  101  indicates a physiological level within a healthy physiological range, an unhealthy physiological range, and/or an inconclusive physiological range, depending on the physiological parameter tested. In one alternate embodiment, the indicator may be an LED that flashes or illuminates a different color based on the actual physiological level calculated. Additionally, in an alternate embodiment, the indication device  300  may be associated with a wireless communication reading, whereby the indication device  300  lights up to indicate a successful or failed wireless data transfer. 
     Referring to  FIG. 6 , a device  100  according to another embodiment of the present invention is illustrated. The device  100  of  FIG. 6  is substantially similar to the device  100  of  FIGS. 2-5 . 
     Referring to  FIG. 7 , a method  700  of using a device  100  according to an embodiment of the present invention is illustrated. At step  701 , when the user is ready to take a reading of a physiological parameter (e.g. glucose, cholesterol, etc.), the user first turns on the device  100  and checks which test sites  200  have yet to be used by looking at the indication device  300  associated with each test site  200  (where applicable). Next, at step  702 , the user pulls the tab  401  of a cover  400  of an unused test site  200 , and peels off the cover  400  (into the second position), thereby exposing the sensor  201 . The sensor  201  is qualified to be exposed to the ambient atmosphere for a specific amount of time without affecting the measurement/reading accuracy of the sensor  201 . 
     At step  703 , within a reasonable amount of time, the user then places a sample (e.g. a blood sample) on the sensor  201 . In one embodiment, the user obtains the blood sample by using a lancet on the tip of one of their fingers, thereby releasing a small amount of their blood. Preferably, the blood sample is placed within the cavity  205  of the sensor  201  and on the reagent  210 . At step  704 , once the sample is located on the sensor  201 , the sample reacts with the reagent  210  in the sensor  201 . 
     As noted above, the removal of the cover from the test site  200  initiates the processor  101  and sensor  201  of the test site  200 . Once the sample is located within the cavity  205  of the sensor  201 , and after a pre-determined period of time (e.g. 5 seconds), a chemical redox reaction occurs and causes a current flow that is measured by the signal conditional means of the processor  101 . By appropriate calculations performed by the data processing means of the processor  101 , the current flow and the current decay is converted to a reading, which is then stored in the memory  104  of the device  100 . Further, in one embodiment, the reading calculated by the processor  101  is an actual physiological level (e.g. glucose level, cholesterol level, etc.) based on the received signal. The actual physiological level is then stored within the memory device  104 . 
     The sensor  201  design causes the biochemically active material (reagent  210 ) to be depleted after one measurement of one sample, which means that each sensor  201  can be used only once. Therefore, when the sample is taken and the measurement is complete, the sensor  201  is no longer usable. Further, it should be noted that the sensor redox reaction is a temperature dependent thermodynamic process and the signal conditioning must take a temperature reading from the temperature sensor  105  into account. 
     At step  706 , the indication device  300  of the test strip  200  being used remains on, while the indication devices  300  of the other test strips  200  turn off. As noted above, in some embodiments, the indication device  300  of the sensor  201  being used may be configured to indicate whether the processor  101  is measuring the sample, whether the measurement is successful/unsuccessful. 
     Finally, at step  707 , after the sensor  201  is used and a measurement taken, the cover  400  may be closed (returned to the first position) to prevent the sample from exiting the test site  200 . Thereafter, the device  100  may be powered down and put away for another use. Since the device  100 , of the present invention may comprise more than one test site  200  (and thus more than one sensor  201 ), the device may be kept for use at a later time. After all the test sites  200  of the device  100  have been used, the device  100  may be returned to a centralized data processing and diagnostics site where the device  100  is scanned and the information retrieved. At the centralized data processing and diagnostics site, the envelope with the device  100  may be scanned with an RFID scanner and the information retrieved therefrom. In such an embodiment, each device  100  will have a device identification number that is used to link the device to a specific patient. The results of the measurements may then be transmitted in encrypted form to a host system for further analysis and diagnosis. In an alternate embodiment, the information located within the memory of the device  100  may be transmitted (either wirelessly or not) to a remote device, where the information may be viewable by the user and/or a physician/doctor. Thereafter, the device may be thrown away. 
     It should be noted, that in one embodiment of the present invention, the device  100  is only good for “one use.” Stated another way, the test sites  200  (and sensors  201 ) the device  100  can only be used once, and after they are used, the device  100  may be discarded. 
     In one embodiment, the device  100  is provided in a package with lancets, sterile wipes for the user&#39;s finger and/or card, and a sealable plastic bad to place the device  100  in for disposal. 
     As noted above, in one embodiment, upon the user peeling the cover  400  off the test site  200  and exposing the sensor  201 , an indicator  300  fixed to the body  120  and operably coupled to the processor  101  provides an indication to the user of: (1) whether the glucose sensor has received a sufficient amount of the blood sample; (2) whether the glucose sensor registered an accurate measurement; and/or (3) whether the glucose sensor registered an inaccurate measurement. Further, in an alternate embodiment, prior to the cover  400  being lifted and uncovering the test site  201 , but after the device  100  is turned on, the indicator  300  may further provide an indication to the user of whether the sensor  201  has been previously used. 
     As used throughout, ranges are used as shorthand for describing each and every value that is within the range. Any value within the range can be selected as the terminus of the range. In addition, all references cited herein are hereby incorporated by referenced in their entireties. In the event of a conflict in a definition in the present disclosure and that of a cited reference, the present disclosure controls.