JP4384556B2 - Biosensor device replacement unit - Google Patents

Description

  The present invention relates to a maintenance method and a sensor unit for a biosensor device applied in the fields of environmental measurement, medical measurement, fermentation / food industry measurement, and the like.

  Biosensors use biological functional materials such as enzymes and antibodies, and living organisms such as microorganisms and cells as molecular identification elements that recognize chemical substances to be measured in sample liquids. The molecular identification signal of the biological material is obtained by a biosensor unit that is combined with a membrane (hereinafter referred to as an immobilized membrane) that is chemically encapsulated or covalently bonded to the membrane and a transducer such as an electrochemical detector. It is a sensor that converts chemical signals into sample water to measure chemical substances in sample water.

  That is, the biosensor brings the sample solution into contact with the immobilized membrane of the biomaterial, and changes the concentration of the substance generated or consumed by the biochemical reaction caused thereby by an electrical output such as current or voltage ( In the present invention, it is converted into a change in the sensor output) and measured.

  FIG. 3 shows an example of the configuration of the biosensor unit. The biosensor unit 1 measures an immobilized membrane 2 on which an enzyme, a microorganism, or the like is immobilized, and an electrode active material, etc., generated by a reaction of the enzyme, the microorganism, or the like in the immobilized membrane with a biological active material in a sample solution The flow transducer 4 is composed of an electrochemical transducer 3 and a flow cell 4. The flow cell 4 supplies a sample solution (reagent and test water) and air to the immobilization membrane 2, and discharges the flow channel 5. A mixing chamber 6 for supersaturating dissolved oxygen in the sample liquid by retaining the liquid and air, and a space for installing the immobilizing film 2 and the electrochemical transducer 3 are provided. The flow cell 4 is installed at an inclination on the biosensor device, so that the sample solution stays in the mixing chamber 6 and the sample solution is supplied as droplets with air to the immobilizing film 2. The bioactive substance in the sample solution can be measured.

  However, since the above-mentioned immobilized membrane deteriorates with time as the measurement is repeated, it is necessary to periodically replace it. Conventionally, only the immobilized membrane has been exchanged as shown in FIG. In FIG. 4, the newly prepared immobilization membrane 8 is sealed in a resin bag 9 filled with a preservative solution in order to maintain the activity of the immobilization membrane, and transported while maintaining the temperature at 5 to 10 ° C. The When replacing the immobilized membrane, the biosensor unit 1 is removed from the biosensor device body 10, the electrochemical transducer 3 is removed from the flow cell 4, and the used immobilized membrane 8a is taken out and discarded. When the flow cell 4 is soiled with precipitates, the soil is removed by physical and chemical treatment. Thereafter, a new immobilized membrane 8 and electrochemical transducer 3 are installed in the flow cell 4 to construct the biosensor unit 1 and then attached to the biosensor device main body 10 until the biosensor output is stabilized, or a threshold value. Measurement was started after confirming that the following.

Therefore, for example, in Patent Document 1 below, the immobilized microbial membrane of a biosensor that performs component analysis of a sample solution by combining an immobilized microbial membrane in which microorganisms are immobilized on a porous membrane and an electrochemical detector. A method for preserving the immobilized microbial membrane is disclosed, which is immersed in a liquid in a sealed container and wet-stored at a low temperature.
JP-A-6-96

  However, in the conventional method of exchanging only the immobilized membrane, the exchange work is complicated and takes time, and it takes time to check and adjust the stability of the sensor output after installing the biosensor unit in the apparatus body. There was a problem.

  In addition, there are problems such as damage to the immobilized membrane during replacement work, and failure of the electrochemical transducer such as air entering between the electrochemical transducer and the immobilized membrane, which will not function as a sensor, Careful attention was required for the replacement work.

Therefore, an object of the present invention is to provide a biosensor device replacement unit that can perform maintenance of a biosensor device reliably and easily and can greatly reduce the working time.

In order to achieve the above object, the exchange unit of the biosensor device of the present invention is formed by bringing a sample solution into contact with an immobilized membrane on which microorganisms or enzymes are immobilized, and components in the sample solution react with the immobilized membrane. A change unit for a biosensor device used for maintenance of a biosensor device in which a change to be detected is detected by an electrochemical transducer , a flow cell having a flow path of a sample solution and an inlet / outlet thereof, and the flow path Bei example the immobilization film disposed so as to be in contact with the sample liquid flowing through the, and electrochemical transducers arranged so as to be able to detect changes due to reaction between the liquid sample and the immobilized membrane, the sample is the flow path to fill the preservation solution to keep the immobilizing film for the activity of the liquid, the inlet and outlet opening of the flow path is connected by a connecting pipe, to characterized in that said preservative solution is encapsulated .

Further, it is preferable that the immobilized membrane is a membrane on which microorganisms are immobilized, and the electrochemical transducer is a dissolved oxygen electrode. Moreover, it is preferable that the said preservation | save liquid is maintained at 5-35 degreeC.

  According to the above invention, it is possible to check the operation of the replacement unit before shipment of the product, and it is possible to check for defects of the immobilization film or electrochemical transducer, liquid leakage, etc., so it is more reliable. A biosensor unit can be provided. Moreover, it is only necessary to perform a simple operation confirmation work after the unit replacement, and it is possible to start up in a short time.

  According to the present invention, maintenance of the biosensor device such as replacement of the immobilized membrane can be reliably and easily performed by unitizing the flow cell, the immobilized membrane, and the electrochemical transducer and exchanging the unit. The working time can be greatly shortened. In addition, since the operation of the replacement unit can be checked before the product is shipped, a more reliable biosensor unit can be provided.

  FIG. 1 shows an embodiment of the exchange unit (biosensor unit) of the present invention during storage and transportation. The exchange unit (biosensor unit) 20 includes an immobilization film 11, an electrochemical transducer 12, and a flow cell 13 having a flow path 14.

  The immobilization film 11 is disposed in the flow cell 13 so as to be in contact with a mixing chamber 15 provided in the middle of the flow path 14, and the electrochemical transducer 12 is opposite to the immobilization film 11. It is arranged so that it touches the surface. That is, after the test water supplied into the flow path 14 from the inlet 14a together with the reagent and air comes into contact with the immobilized membrane 11 in a state where the dissolved oxygen is supersaturated by staying in the mixing chamber 15, It is discharged from the discharge port 14b. The electrochemical transducer 12 can detect and measure the change caused by the reaction between the test water and the immobilization film 11.

  The flow path 14 is filled with a preserving liquid for maintaining the activity of the immobilizing membrane 11, and the inlet 14a and the outlet 14b are connected by a connecting pipe 16 filled with the preserving liquid or air. By doing so, it is possible to prevent leakage of the preservation solution and to prevent the propagation of various germs. The piping member 16 is detachably attached to the replacement unit 20, and can be easily removed when the replacement unit is used.

  Known immobilization membranes used in the present invention include microorganisms such as ammonia-oxidizing bacteria (nitrosomonas), nitrite-oxidizing bacteria (nitrobacter), iron-oxidizing bacteria, trichospon, and luminous bacteria, or enzymes such as glucose oxidase and peroxidase. A membrane immobilized in accordance with the above method can be used. In the present invention, a membrane in which microorganisms are immobilized (an immobilized microorganism membrane) is preferably used, and in particular, a membrane in which ammonia-oxidizing bacteria and nitrite-oxidizing bacteria are immobilized is preferably used. The immobilized microbial membrane is prepared by, for example, suspending a microorganism in an aqueous sodium alginate solution, dropping the suspension onto a porous cellulose membrane, sandwiching the suspension with another cellulose membrane, and gelling sodium alginate with an aqueous calcium chloride solution. Can be prepared by immobilizing the cells.

  The electrochemical transducer may be any one that can measure changes in the electrode active material and the like produced by the reaction of microorganisms and enzymes in the immobilized membrane with the biological active material in the test water. Examples thereof include a dissolved oxygen electrode, a photomultiplier, a photodiode, and a pH meter. As the electrochemical transducer, the most suitable one can be selected depending on the type of the immobilized film. In the present invention, it is preferable to use a dissolved oxygen electrode.

  The material of the connecting pipe 16 may be any material that has chemical resistance to the storage solution. Specifically, the material has good oxygen permeability such as silicon, resin such as fluorine resin, metal such as SUS, ceramic. Etc. can be illustrated.

  Moreover, as a preservation | save liquid with which the flow path 13 of the flow cell 13 is filled, when using the immobilized microorganism membrane of ammonia oxidation bacteria, for example, ammonia serving as a bait is added to a borate buffer solution having a buffer capacity of pH 8-9. Additions etc. are mentioned.

Next, a maintenance method for the biosensor device of the present invention will be described.
FIG. 2 shows an outline of a maintenance method for the biosensor device of the present invention. In FIG. 2, the same components as those in FIG. 1 are denoted by the same reference numerals, and the description thereof is omitted.

  In FIG. 2, a newly manufactured immobilization film 11 and electrochemical transducer 12 are set at predetermined positions in the flow cell 13 at the manufacturer / supplier, and a new replacement unit (biosensor unit) 20 is constructed ( Step A).

  This new replacement unit (biosensor unit) 20 is set in the start-up device 21 in order to check the malfunction of the immobilized membrane and the electrochemical transducer, etc. until the biosensor output is stabilized or the threshold value is set. Confirm that it is as follows (step B). The start-up device 21 includes a thermostatic chamber for controlling the temperature of the biosensor unit, a feed solution (pH buffer solution containing microorganism feed) or a pH buffer solution to the biosensor unit, like the biosensor device body. It is equipped with a liquid pump that supplies pure water, an air pump that supplies air to the biosensor unit, a heat exchanger that controls the temperature of the feed liquid and air, etc., and confirms the operation of the replacement unit. Can be done.

  Thereafter, the flow path of the flow cell 13 is filled with the storage liquid 22 so that the storage liquid 22 comes into contact with the immobilization membrane 11 and the flow path 13 is connected to the inlet / outlet of the flow path with a connecting pipe so that the storage liquid 22 does not leak. transport. During storage and transportation, it is preferable to keep the temperature at 5 to 35 ° C. so that microorganisms and enzymes on the immobilized membrane of the exchange unit are not killed or inactivated.

  At the place where the biosensor is used, the used biosensor unit 20a is removed from the biosensor device body 30, and a new replacement unit (biosensor unit) 20 from which the connecting pipe is removed is attached to the device body 30, and the biosensor. Confirm that the output is stable or below the threshold (step D). At this time, since the biosensor output of the replacement unit (biosensor unit) 20 is stabilized at the time of shipment, the time for stabilizing the biosensor output can be shortened as compared with the conventional case. Furthermore, since the unit is attached to the main body of the apparatus without disassembling the biosensor unit, the maintenance time is greatly reduced, and the risk of occurrence of defects in the immobilized membrane and the electrochemical transducer can be reduced.

  On the other hand, the used biosensor unit 20a is recycled by returning it to the manufacturer / supplier. That is, the returned used biosensor unit 20a is disassembled, the used immobilization film 11a is discarded (step E), and the electrochemical transducer 12 and the flow cell 13 are appropriately subjected to necessary maintenance. After being broken (step F), a new exchange unit (biosensor unit) is constructed using the new immobilized membrane.

  The method of the present invention is suitable for a maintenance method of a biosensor device applied in the fields of environmental measurement, medical measurement, fermentation / food industry measurement, and the like.

It is a schematic diagram which shows one Embodiment of the exchange unit (sensor unit) of this invention. It is explanatory drawing which shows the outline of the maintenance method of the biosensor apparatus of this invention. It is a schematic diagram which shows an example of a structure of a biosensor unit. It is explanatory drawing which shows the outline of the maintenance method of the conventional biosensor apparatus.

Explanation of symbols

11. Immobilization membrane 12. Electrochemical transducer 13. Flow cell 14. Flow path 15. Mixing chamber 20. Replacement unit (biosensor unit)
21. Startup device 22. Stock solution 30. Biosensor device body

Claims (3)

A biosensor device in which a sample solution is brought into contact with an immobilized membrane on which microorganisms or enzymes are immobilized, and a change formed by a reaction of a component in the sample solution with the immobilized membrane is detected by an electrochemical transducer. An exchange unit for a biosensor device used for maintenance of
A flow cell having a flow path for sample liquid and an inlet / outlet thereof, the immobilization film disposed so as to be in contact with the sample liquid flowing through the flow path, and a change due to a reaction between the immobilization film and the sample liquid are detected. Bei example an electrochemical transducer disposed so as to be,
A biosensor device , wherein the flow path of the sample liquid is filled with a preserving liquid that keeps the immobilized membrane active, and the preserving liquid is sealed by connecting an outlet / inlet of the flow path with a connecting pipe. Replacement unit. The immobilized membrane is a membrane with immobilized microorganisms, the exchange unit of the biosensor device of the electrochemical transducer according to claim 1 is a dissolved oxygen electrode. The biosensor device replacement unit according to claim 1 or 2, wherein the preservation solution is maintained at 5 to 35 ° C.

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