Abstract:
A body fluid component analyzing system allows parameters to be calibrated without changing memory keys even if the production lot of sensor chips is changed. The system comprises a measurement instrument having a calculating mechanism for calculating a characteristic of a component, a sensor chip storage unit containing one or more sensor chips which sense a characteristic of at least one component of a body fluid and a storage case in which the measurement unit, and possibly also the sensor chip storage unit, can be placed. The calculation parameters of one or more sensor chips can be automatically transferred to the measurement instrument by way of a transfer device.

Description:
TECHNICAL FIELD  
       [0001]     The present invention relates to a body fluid component analyzing system for quantitatively or qualitatively analyzing components of a body fluid, such as glucose, hemoglobin, etc. More specifically, the present invention is concerned with a body fluid component analyzing system including a measuring instrument having processing means, which is connected to a sensor chip having a reactive member for reacting with a component of a body fluid depending on characteristics thereof, for processing the characteristics of the component, a sensor storage unit such as a sensor container or the like for storing or packaging sensor chips, and a storage case for storing the measuring instrument and the sensor storage unit.  
       BACKGROUND ART  
       [0002]     Heretofore, it has been customary to pierce the skin of a finger, an arm, an ear, or the like, sample a small amount of blood through the pierced skin, and measure various components of the blood using the sampled blood. Particularly, the measurement of a blood glucose level in a diabetic patient is important for monitoring the state of the diabetic patient. It has been recommended for the patient to perform a self glucose monitoring process to monitor daily blood glucose level changes. In view of a growing number of diabetic patients in recent years, there has been a demand for measuring processes and measuring means that are simple and painless.  
         [0003]     Blood glucose levels are often measured using the reaction of an enzyme such as glucose oxidase, glucose dehydrogenase, or the like to oxidize glucose. At present, the measurement of a blood glucose level is performed by a blood glucose measuring device according to a colorimetric process for setting in place a test paper which produces a color depending on the amount of blood glucose brought into contact therewith, supplying the test paper with the blood to cause the test paper to give a color, and optically measuring the grade of the color to quantify the blood glucose level (see, for example, Japanese Patent Laid-open No. Sho 63-101757), or an electrode process for electrically measuring a product resulting from the enzymatic reaction referred to above (see, for example, Japanese Patent Laid-open No. Sho 60-17344).  
         [0004]     According to the above measuring processes, a dedicated skin-piercing tool, i.e., a needle-like or knife-like piercing means known as a lancet, is used to form a cut in the skin of a patient&#39;s finger or the like to allow a body fluid such as the blood to bleed, and the body fluid is transferred to a separately prepared test chip having a test paper or an electrode sensor or the like, and then measured by the blood glucose measuring device (see, for example, Japanese Patent Laid-open No. Hei 7-167786).  
         [0005]     For correcting variations of test papers or electrode sensors which occur from production lot to production lot, there have been known a system for recording a parameter for correcting sensor performance variations in a sensor chip (see, for example, Japanese Patent Laid-open No. Hei 7-209242) and a system for using a memory key recording a parameter depending on the production lot of sensor chips and loading the memory key into a measuring device to read the parameter into the measuring device (see, for example, Japanese Translations of PCT for Patent No. Hei 8-502590 and Japanese Translations of PCT for Patent No. Hei 11-510915).  
         [0006]     If the memory key is used, however, the memory key needs to be replaced each time a sensor chip of a different production lot is employed. Therefore, it is awkward for the user to use the memory key.  
         [0007]     The present invention solves the problems of the above prior art. It is an object of the present invention to provide a simple body fluid component analyzing system which does not require the user to replace a memory key each time a sensor chip of a different production lot is employed.  
       DISCLOSURE OF INVENTION  
       [0008]     The above object can be achieved by structures (1) through (11) of the present invention as described below.  
         [0009]     (1) A body fluid component analyzing system according to the present invention includes a sensor chip for detecting characteristics of at least one component of a body fluid, a measuring instrument having processing means, to which the sensor chip is adapted to be connected, for processing the characteristics of the component, a sensor chip storage unit for storing or packaging at least one the sensor chip, a storage case for storing at least the measuring instrument, parameter recording means applied to or indicated on the sensor chip storage unit, for recording at least one parameter used when the processing means of the measuring instrument processes the characteristics, parameter receiving means provided in the measuring instrument, for receiving the parameter recorded by the parameter recording means, and transfer means for transferring the parameter recorded by the parameter recording means to the parameter receiving means disposed in the measuring instrument while at least the measuring instrument is being stored in the storage case.  
         [0010]     (2) A body fluid component analyzing system according to the present invention includes a sensor chip for detecting characteristics of at least one component of a body fluid, a measuring instrument having processing means, to which the sensor chip is adapted to be connected, for processing the characteristics of the component, a sensor chip storage unit for storing or packaging at least one the sensor chip, a storage case for storing the measuring instrument and the sensor chip storage unit, parameter recording means applied to or indicated on the sensor chip storage unit, for recording at least one parameter used when the processing means of the measuring instrument processes the characteristics, parameter receiving means disposed in the measuring instrument, for receiving the parameter recorded by the parameter recording means, and transfer means disposed in the storage case, for reading and transferring the parameter recorded by the parameter recording means to the parameter receiving means disposed in the measuring instrument while the measuring instrument and the sensor chip storage unit are being stored in the storage case.  
         [0011]     (3) The transfer means is detachably disposed in the storage case.  
         [0012]     (4) The parameter represents calibrating information for correcting variations of the performance of the sensor chip.  
         [0013]     (5) The transfer means transfers the parameter while the measuring instrument and the sensor chip storage unit are being positioned in the storage case.  
         [0014]     (6) The transfer means may include an electric transfer arrangement for transferring the parameter between the parameter recording means and the parameter receiving means through electric contacts.  
         [0015]     (7) The transfer means may include an optical transfer arrangement for optically transferring the parameter between the parameter recording means and the parameter receiving means.  
         [0016]     (8) The parameter transferred from the parameter recording means to the parameter receiving means by the optical transfer arrangement includes optical information represented by a bar code.  
         [0017]     (9) The transfer means may include an acoustic transfer arrangement for acoustically transferring the parameter between the parameter recording means and the parameter receiving means.  
         [0018]     (10) The transfer means may include a radio-wave transfer arrangement for transferring the parameter between the parameter recording means and the parameter receiving means by way of a radio wave.  
         [0019]     (11) The transfer means may include an electromagnetic transfer arrangement for electromagnetically transferring the parameter between the parameter recording means and the parameter receiving means.  
         [0020]     When the sensor storage unit in which at least one sensor chip is stored or packaged and the measuring instrument are stored in the storage case, at least one parameter of the sensor chip is automatically transferred from the parameter recording means applied to or indicated on the sensor storage unit to the parameter receiving means of the measuring instrument by the transfer means, and the parameter of the measuring instrument is automatically calibrated. Therefore, the parameter can be calibrated without the need for loading the sensor chip into the measuring instrument each time the lot for the sensor chip is changed. 
     
    
     BRIEF DESCRIPTION OF DRAWINGS  
       [0021]      FIGS. 1A and 1B  are perspective views of a measuring instrument and a sensor chip and an enlarged perspective view of the sensor chip in a body fluid component analyzing system according to an embodiment of the present invention;  
         [0022]      FIG. 2  is a block diagram of a body fluid component analyzing system according to an embodiment of the present invention;  
         [0023]      FIGS. 3A and 3B  are perspective views of a sensor chip storage unit in the body fluid component analyzing system according to the embodiment of the present invention;  
         [0024]      FIG. 4  is a perspective view illustrating an electric parameter transfer arrangement for use in the body fluid component analyzing system according to the present invention;  
         [0025]      FIG. 5  is a perspective view illustrating an optical parameter transfer arrangement for use in the body fluid component analyzing system according to the present invention;  
         [0026]      FIG. 6  is a perspective view illustrating an acoustic parameter transfer arrangement for use in the body fluid component analyzing system according to the present invention;  
         [0027]      FIG. 7  is a perspective view illustrating a radio-wave parameter transfer arrangement for use in the body fluid component analyzing system according to the present invention;  
         [0028]      FIG. 8  is a perspective view illustrating a contactless parameter transfer arrangement for use in the body fluid component analyzing system according to the present invention;  
         [0029]      FIG. 9  is a perspective view illustrating a parameter transfer arrangement using, as a medium, a storage case of the body fluid component analyzing system according to the present invention; and  
         [0030]      FIG. 10  is a perspective view illustrating the parameter transfer arrangement using, as a medium, the storage case of the body fluid component analyzing system according to the present invention, with a transfer function section being detachable.  
     
    
     DETAILED DESCRIPTION  
       [0031]     Embodiments of a body fluid component analyzing system according to the present invention will be described below with reference to the drawings.  
         [0032]      FIGS. 1A and 1B  schematically show a sensor chip  1  and a measuring instrument  11  such as a blood glucose level measuring instrument or the like. The sensor chip  1  has a reactive member  2  for reacting with a component such as a blood glucose level or the like and electrode terminals  3 . The measuring instrument  11  has a sensor chip mount  12  such as a slit or the like for removably mounting the sensor chip  1  therein, a component display unit  13  such as a liquid crystal panel or the like for digitally displaying a component such as a blood glucose level or the like, and a switch  14  such as a switch button or the like.  
         [0033]     In use, the electrode terminals  3  of the sensor chip  1  are removably mounted in the sensor chip mount  12  of the measuring instrument  11 .  
         [0034]     After a finger of a hand of the patient is pierced by a piercing tool or the like to draw a body fluid such as the blood or the like therefrom, the drawn body fluid such as the blood or the like is applied as a dot or drop to the reactive member  2  of the sensor chip  1  mounted in the tip end of the measuring instrument  11 . The switch  14  is turned on to digitally display the value of a component such as a blood glucose level or the like in the body fluid on the component display unit  13 .  
         [0035]     Details of the body fluid component analyzing system according to the present invention will be described below.  
         [0036]      FIG. 2  is a block diagram showing a general arrangement of the body fluid component analyzing system. The body fluid component analyzing system performs an automatic calibrating process automatically in a storage case  31  for correcting performance variations due to different manufacturing lots of sensor chips  1 .  
         [0037]      FIG. 3A  shows a sensor chip storage unit  22  which is a container with an openable/closable lid  21  for storing a number of (e.g., 20 to 50) sensor chips  1  of one production lot in a sensor chip storage space  20  formed as an inner space.  FIG. 3B  shows a sensor chip storage unit  24  having a small number of (one to several) sensor chips  1  packaged in a package  23 . A bar code  44  is used to acquire parameters with an optical parameter transmission arrangement described later on.  
         [0038]     The body fluid component analyzing system shown in  FIG. 2  may be implemented with either one of the two sensor chip storage units  22 ,  24 . In this embodiment described below, the sensor chip storage unit  22  is used.  
         [0039]     The storage case  31  has a positioning unit  32  for the measuring instrument  11  and a positioning unit  33  for the sensor chip storage unit  22 . The two positioning unit  32 ,  33  are disposed adjacent to each other in the storage case  31 . The measuring instrument  11  and the sensor chip storage unit  22  are stored and positioned respectively in the positioning units  32 ,  33 .  
         [0040]     A parameter recording means  34  for recording at least one parameter which represents calibrating information (a calibrating coefficient for sensor output, etc.) for correcting variations of the performance of the sensor chips  1  stored in the sensor chip storage unit  22  is applied to or indicated on one of the side faces of the sensor chip storage unit  22 . A parameter receiving means  35  is applied to a confronting side face of the measuring instrument  11 . The parameter stored in the parameter recording means is common among the sensor chips stored in the storage case  31 . Thus, the parameter is identical in each lot.  
         [0041]     When the measuring instrument  11  and the sensor chip storage unit  22  are inserted and positioned respectively in the positioning units  32 ,  33 , the parameter recording means  34  and the parameter receiving means  35  are brought into contact with each other or closely to each other.  
         [0042]     A transfer means  36  then automatically transfers the at least one parameter of the sensor chips  1  from the parameter recording means  34  of the sensor chip storage unit  22  to the parameter receiving means  35  of the measuring instrument  11 , and the transferred parameter is input to a processor  15 . The processor  15  automatically corrects a performance variation of the sensor chips  1  due to a production lot difference or the like, and stores the corrected performance variation into a memory  16 . As shown in  FIG. 2 , the measuring instrument  11  comprises, in addition to other features, a measuring unit  17 , a power supply  18 , and a buzzer  19  serving as alarm means. For measuring a component of a body fluid such as a blood glucose level as described above, the switch  14  is turned on to enable the processor  15  to process characteristics of a component of a body fluid that is measured by the measuring unit  17 , store the processed characteristics in the memory  16 , and digitally display the processed characteristics on the display unit  13 . If a measurement error occurs or the characteristics exceed a reference value, then the processor  15  controls the buzzer  19  to give an alarm.  
         [0043]     Specific examples of the body fluid component analyzing system according to the present invention will be described below with reference to  FIGS. 4-8 .  
         [0044]     A body fluid component analyzing system shown in  FIG. 4  employs an electric transfer arrangement as the transfer means  36 . The parameter recording means  34  of the sensor chip storage unit  22  and the parameter receiving means  35  of the measuring instrument  11  include at least a pair of electric contacts  41 ,  42 . The positioning units  32 ,  33 , which are cut out along the profiles of the measuring instrument  11  and the sensor chip storage unit  22  respectively are disposed adjacent to each other in the storage case  31 . An insertion unit  37  for inserting the transfer means  36  therein is formed as a recess in the region across which the positioning units  32 ,  33  are disposed adjacent to each other. A detection switch  43  is disposed on the bottom of the positioning unit  32 , for example. The detection switch  43  serves as a switch for detecting when the measuring instrument  11  is placed in the storage case  31 . The detection switch  43  may be any switch such as a mechanical switch, an electrical switch, or the like insofar as it can detect when the measuring instrument  11  is placed in the storage case  31 .  
         [0045]     When the measuring instrument  11  and the sensor chip storage unit  22  are properly set (inserted and positioned) in the respective positioning units  32 ,  33  in the storage case  31 , the electric contacts  441 ,  42  are brought into contact with each other in the insertion unit  37 . The detection switch  43  detects when the measuring instrument  11  is set in the positioning unit  32 , for example. Then, the process of automatically transferring the parameter from the sensor chip storage unit  22  to the measuring instrument  11  is performed. The automatic parameter transfer process is performed successively at certain time intervals (e.g., in every hour). According to the present invention, simply when the measuring instrument  11  and the sensor chip storage unit  22  are mounted in the storage case  31 , the parameter is thereafter automatically periodically transferred from the sensor chip  22  to the measuring instrument  11 . Consequently, as the parameter is calibrated without troubling the user (while the user is unconscious), the body fluid component analyzing system is convenient to use. Once the parameter calibrating process is performed, the automatic parameter transfer may be stopped until the measuring instrument  11  and/or the sensor chip storage unit  22  is removed (the detection switch  43  also detects when the measuring instrument  11  and/or the sensor chip storage unit  22  is removed), thereby simplifying the entire process.  
         [0046]      FIG. 5  shows a body fluid component analyzing system wherein an optical transfer arrangement is employed as the transfer means  36 . The parameter recording means  34  of the sensor chip storage unit  22  includes optically readable indicating means such as the bar code  44  (see  FIG. 3B ) or the like. The parameter receiving means  35  of the measuring instrument  11  is constructed as light-reflecting reading means including a light-emitting element  45  such as an LED or the like and a light-detecting element  46  such as a phototransistor or the like.  
         [0047]     When the measuring instrument  11  and the sensor chip storage unit  22  are properly set in the respective positioning units  32 ,  33  in the storage case  31 , the bar code  44  is illuminated by the light-emitting element  45  across the insertion unit  37 , and reflects light which is detected by the light-detecting element  46 . The parameter represented by the bar code  44  is automatically transferred from the sensor chip storage unit  22  to the measuring instrument  11  as described above.  
         [0048]     Since the bar code  44  can be used by the optical transfer arrangement, it is sufficiently possible to employ the sensor chip storage unit  24  which has the small number of (one to several) sensor chips  1  packaged in the package  23 , as shown in  FIG. 3B , as the sensor chip storage unit.  
         [0049]      FIG. 6  shows a body fluid component analyzing system wherein an acoustic transfer arrangement is employed as the transfer means  36 . The parameter recording means  34  of the sensor chip storage unit  22  includes an acoustic oscillating means  47  which oscillates acoustically. The parameter receiving means  35  of the measuring instrument  11  is constructed as an acoustic transmitting and receiving means (e.g., means using a high-frequency wave such as a telephonic pulse or push-tone wave)  48  for transmitting and receiving acoustic energy.  
         [0050]     When the measuring instrument  11  and the sensor chip storage unit  22  are properly set in the respective positioning units  32 ,  33  in the storage case  31 , the acoustic transmitting and receiving means  48  oscillates a high-frequency wave, and the acoustic oscillating means  47  is vibrated thereby across the insertion unit  37 , whereupon the parameter is automatically transferred from the sensor chip storage unit  22  to the measuring instrument  11  in the same manner as described above.  
         [0051]      FIG. 7  shows a body fluid component analyzing system wherein a radio-wave transfer arrangement is employed as the transfer means  36 . The parameter recording means  34  of the sensor chip storage unit  22  includes a radio-wave transmitting means  49 , and the parameter receiving means  35  of the measuring instrument  11  is constructed as a radio-wave transmitting and receiving means  50 .  
         [0052]     When the measuring instrument  11  and the sensor chip storage unit  22  are properly set in the respective positioning units  32 ,  33  in the storage case  31 , the radio-wave transmitting and receiving means  49  sends radio-wave information to the radio-wave transmitting and receiving means  50  across the insertion unit  37  due to the reflection of a radio wave transmitted from the radio-wave transmitting and receiving means  50 , whereupon the parameter is automatically transferred from the sensor chip storage unit  22  to the measuring instrument  11  in the same manner as described above.  
         [0053]      FIG. 8  shows a body fluid component analyzing system wherein a contactless proximity transfer arrangement is employed as the transfer means  36 . A storage region  31   a  which is widely open in the storage case  31  has no positioning units disposed therein for the measuring instrument  11  and the sensor chip storage unit  22 . Therefore, the measuring instrument  11  and the sensor chip storage unit  22  are housed in the storage region  31   a  without being positionally limited. A contactless transfer means  51  such as the radio-wave (electromagnetic) transfer arrangement, the acoustic transfer arrangement, or the like as described above is disposed on the bottom of the storage region  31   a . When the sensor chip storage unit  22  approaches the contactless transfer means  51 , the parameter of the parameter recording means  34  is read by the contactless transfer means  51 , and automatically transferred to the parameter receiving means  35  of the measuring instrument  11 . With this structure, the measuring instrument  11  and the sensor chip storage unit  22  are not required to be positioned at particular places, but may be moved within the storage case  31 , as indicated by the arrows A, B. However, since both the measuring instrument  11  and the sensor chip storage unit  22  as they are placed in the storage case  31  have to be detected by something like the detection switch  43 , if the detection switch  43  includes a contact-type switch, then it is desirable that either one of the measuring instrument  11  and the sensor chip storage unit  22  be disposed for contact with the detection switch  43 .  
         [0054]      FIG. 9  shows a body fluid component analyzing system wherein an indirect transfer arrangement is employed which uses the storage case  31  as a medium. A transmitter  53  and a receiver  54  of an indirect transfer means  52  such as the electric transfer arrangement, the optical transfer arrangement, the acoustic transfer arrangement, the radio-wave (electromagnetic) transfer arrangement, or the like as described above are disposed on the bottoms of the positioning units  32 ,  33  of the measuring instrument  11  and the sensor chip storage unit  22  in the storage case  31 . When the measuring instrument  11  and the sensor chip storage unit  22  are set in the respective positioning units  32 ,  33 , the parameter recording means  34  disposed on the bottoms of the sensor chip storage unit  22  and the measuring instrument  11  contact or approach the transmitter  53  and the receiver  54  of the indirect transfer means  52 . The parameter of the parameter recording means  34  of the sensor chip storage unit  22  is read by the transmitter  53 , and transferred by the indirect transfer means  52  to the parameter receiving means  35  of the measuring instrument  11  through the receiver  54 .  
         [0055]      FIG. 10  shows a transfer function section detached from the indirect transfer arrangement according to the embodiment shown in  FIG. 9 . The transfer means of the indirect transfer arrangement is detachable from the storage case. This structure allows the parameter to be calibrated outside of the storage case.  
         [0056]     Although the embodiments of the present invention has been described above, the present invention is not limited to the above embodiments, but various changes and modifications may be made therein based on the technical concept of the present invention.  
         [0057]     For example, in the above embodiments, both the measuring instrument  11  and the sensor chip storage unit are stored in the storage case  31  for automatically transferring the parameter. However, only the measuring instrument  11  may be stored (set) in the storage case, and the sensor chip storage unit  22  may be brought close to the storage case to automatically transfer the parameter from the sensor chip storage unit  22  to the measuring instrument  11 .  
         [0058]     Since the body fluid component analyzing system thus constructed according to the present invention is capable of automatically transferring the parameter from the sensor chip to the measuring instrument, the parameter can automatically be calibrated when the lot for the parameter is changed without the need for the user to replace a memory key or to load the parameter into the measuring instrument each time the lot for the parameter is changed.  
         [0059]     When the lot of the sensor chip which is a consumable product requiring calibration at present is changed, information that is required for calibrating the parameter can reliably be input to the measuring instrument while the user is unconscious, so that the measuring accuracy of the measuring instrument is maintained. Therefore, the diabetic patient can measure a blood glucose level at ease.  
         [0060]     Since the user is not required to be conscious, the user can use the body fluid component analyzing system in substantially the same manner as when no parameter is calibrated, so that the diabetic patient is less troubled by the use of the system.  
         [0061]     In the embodiment which applies the optical measurement, only a bar code or another code may be placed on the sensor chip storage unit, and hence the expenses of the sensor chip which is a consumable product are not increased. As no special device needs to be added to the storage case, the expenses of the storage case are not increased.