Method for oxidation-reduction of target molecule and apparatus for oxidation-reduction of target molecule

Abstract

A method according to the present invention for oxidizing or reducing a target molecule, said method comprising: a first step (S103) for, while holding a target molecule-containing liquid in a non-fluidized state, allowing electron transfer between an electron carrier, said electron carrier being immobilized to an electrode connected to an external power supply outside the liquid, and the target molecule to thereby oxidize or reduce the target molecule; and a second step (S104) for fluidizing the liquid. The first step (S103) and the second step (S104) are sequentially repeated.

Description

[Technical field]

[0001] The present disclosure relates to the oxidation and reduction of electron carriers using electrochemical techniques. [Background technology]

[0002] The electron donor, which is the reductant of the electron carrier, reduces the electron acceptor by donating electrons to the electron acceptor. At this time, the electron donor is oxidized to become an oxidant, and is therefore unable to reduce a new target molecule (i.e., the electron acceptor). On the other hand, in a redox reaction in vivo, multiple types of substances function as electron donors and electron acceptors, and there is a mechanism in which the reduced form of the electron carrier is reduced again to return to the reduced form even if it is oxidized by the transfer of electrons between these substances. Since such a mechanism does not exist in a redox reaction outside of a body, the oxidant is usually reduced by donating electrons to the oxidized form of the electron carrier from an electrode using an electrochemical measuring device or the like. Summary of the Invention [Problem to be solved by the invention]

[0003] An object of the present disclosure is to provide a method for oxidation-reduction of a target molecule and an apparatus for oxidation-reduction of a target molecule, which are capable of efficiently oxidizing or reducing a target molecule in an entire reaction system. [Means for solving the problem]

[0004] A method for oxidizing or reducing a target molecule according to one embodiment of the present disclosure includes a first step of bringing a liquid containing an inactive target molecule into a non-flowing state and transferring electrons between the inactive target molecule and an electron carrier fixed to an electrode connected to an external power source outside the liquid, thereby oxidizing or reducing the inactive target molecule, and a second step of bringing the liquid into a flowing state, and the first step and the second step are sequentially repeated. Effect of the Invention

[0005] According to the present disclosure, there is provided a method for oxidation-reduction of a target molecule and an apparatus for oxidation-reduction of a target molecule, which can efficiently oxidize or reduce a target molecule in an entire reaction system. [Brief description of the drawings]

[0006] [Figure 1] FIG. 1 is a diagram showing an example of the configuration of a target molecule oxidation-reduction device according to an embodiment. [Diagram 2] FIG. 2 is a perspective view of a voltage application unit according to the embodiment. [Diagram 3] FIG. 3 is a cross-sectional view taken along line III-III in FIG. [Figure 4] FIG. 4 is a cross-sectional view taken along line IV-IV in FIG. [Diagram 5] FIG. 5 is a diagram illustrating an example of a functional configuration of a target molecule oxidation-reduction device according to an embodiment. [Figure 6] FIG. 6 is a flowchart showing an example of the operation of the target molecule oxidation-reduction device according to the embodiment. [Figure 7] FIG. 7 is a diagram showing the absorption spectra of the target molecule solution near the cathode electrode and near the counter electrode (far from the cathode electrode) in Example 1. [Figure 8] FIG. 8 is a graph showing the absorbance at 340 nm of the entire target molecule solutions of Example 1, Comparative Example 1, and Comparative Example 2. [Figure 9] FIG. 9 is a diagram showing the absorption spectra of the target molecule solution near the cathode electrode and near the counter electrode (far from the cathode electrode) in Comparative Example 1. [Figure 10] FIG. 10 is a diagram showing the absorption spectra of the target molecule solution near the cathode electrode and near the counter electrode (far from the cathode electrode) in Comparative Example 2. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0007] (Findings on which this disclosure is based) As described above, in the conventional technology, the oxidant of the electron carrier is reduced by donating electrons from the cathode electrode of the electrochemical measurement device to the oxidant. However, it is difficult for the oxidant to directly accept electrons from the cathode electrode. Therefore, by fixing an electron donor to the cathode electrode, the electron donor donates the electrons it has accepted from the cathode electrode to a target molecule (i.e., an electron acceptor). As a result, the target molecule indirectly accepts electrons from the electrode and is reduced.

[0008] The electron transfer reaction between the electron donor immobilized on the cathode electrode and the target molecule is a very localized reaction that occurs only around the cathode electrode, and most of the target molecules are not reduced in the entire reaction system (i.e., the activation efficiency is low). Therefore, there is a need to construct a reaction system that has high reduction efficiency of the target molecule in the entire reaction system.

[0009] Therefore, an object of the present disclosure is to provide a method for oxidation-reduction of a target molecule and an apparatus for oxidation-reduction of a target molecule, which can efficiently oxidize or reduce a target molecule in the entire reaction system.

[0010] (One aspect of the present disclosure) One aspect of the present disclosure is as follows.

[0011] A method for oxidizing or reducing a target molecule according to one embodiment of the present disclosure includes a first step of bringing a liquid containing the target molecule into a non-flowing state and transferring electrons between the target molecule and an electron carrier fixed to an electrode connected to an external power source outside the liquid, thereby oxidizing or reducing the target molecule, and a second step of bringing the liquid into a flowing state, and the first and second steps are sequentially repeated.

[0012] As a result, in the first step, when the liquid is in a non-flowing state, an electron transfer reaction occurs between the electron carrier immobilized on the electrode and the target molecule, and a stable reaction field is easily formed. As a result, the activation efficiency of the target molecule is improved. In addition, by making the liquid in a flowing state in the second step, the activated target molecule is diffused from the vicinity of the electrode, and other target molecules in the liquid are easily moved to the vicinity of the electrode. As a result, more target molecules in the liquid can perform an electron transfer reaction with the electron carrier, and the efficiency of the electron transfer reaction between the target molecule and the electron carrier is improved. In addition, since the first step and the second step are sequentially repeated, the target molecule can be continuously activated. Therefore, according to the method for oxidation-reduction of a target molecule, the target molecule can be efficiently activated in the entire reaction system (i.e., the liquid).

[0013] In the method for oxidizing and reducing a target molecule according to one aspect of the present disclosure, in the second step, the liquid may be brought into a fluidized state by stirring or shaking the liquid.

[0014] This causes the active target molecules to diffuse away from the vicinity of the electrodes, and other target molecules in the liquid move closer to the electrodes. Effectively It can be activated efficiently.

[0015] In the method for oxidizing and reducing a target molecule according to one aspect of the present disclosure, a period of time required for the first step may be longer than a period of time required for the second step.

[0016] This allows more time for activation of the target molecules, and therefore more target molecules can be activated.

[0017] In the method for oxidizing and reducing a target molecule according to one aspect of the present disclosure, the ratio of the execution time of the first step to the execution time of the second step may be 10 to 100:1.

[0018] This allows sufficient time for the electron transfer reaction between the electron carrier and the target molecule, making it possible to activate a larger number of target molecules.

[0019] In the method for oxidizing and reducing a target molecule according to one embodiment of the present disclosure, the first step may be performed for a period of 30 minutes or more and 90 minutes or less, and the second step may be performed for a period of 1 minute or more and 2 minutes or less.

[0020] This allows sufficient time for the electron transfer reaction between the electron carrier and the target molecule, making it possible to activate a larger number of target molecules.

[0021] In a method for oxidizing and reducing a target molecule according to one aspect of the present disclosure, the target molecule is NADP + may be also possible.

[0022] This produces NADPH as an active target substance, which can activate redox molecules, redox enzymes, redox proteins, and the like involved in various redox reactions.

[0023] In the method for oxidizing and reducing a target molecule according to one aspect of the present disclosure, the electrode may have a substrate containing gold.

[0024] This makes it possible to obtain an electrode with low chemical reactivity and resistance to corrosion. In addition, since gold has a high binding affinity for molecules having sulfur, nitrogen, or oxygen atoms, it is easy to modify the surface, and thus it is possible to obtain an electrode with functionality.

[0025] In the method for oxidizing and reducing a target molecule according to the embodiment of the present disclosure, the electron carrier may be a 4,4'-bipyridinium derivative. For example, the electron carrier may be 1-methyl-1'-hexyl-4,4'-bipyridinium.

[0026] In this way, by using a 4,4'-bipyridinium derivative as an electron carrier, the affinity of the electron carrier to the enzyme is increased. Therefore, the electron carrier can be used, for example, as a coenzyme involved in the redox reaction (NADP +), as well as interacting with enzymes and proteins. Furthermore, by using 1-methyl-1'-hexyl-4,4'-bipyridinium as an electron carrier, Electron carrier substrate fart This makes it easier to fix the

[0027] In the method for oxidizing and reducing a target molecule according to one aspect of the present disclosure, the voltage application from the external power source may be performed in the first step.

[0028] This allows electrons to be donated from the electrode to the electron carrier, so that an electron transfer reaction can be efficiently carried out between the electron carrier and the target molecule.

[0029] In addition, a target molecule oxidation-reduction device according to one embodiment of the present disclosure includes a stirring unit that stirs a liquid containing a target molecule to create a fluid state, an electrode to which an electron carrier is fixed that reduces the target molecule to an active target molecule by transferring electrons between the electrode, a power source that applies a voltage to the electrode, and a control unit that controls the power source and the stirring unit, and the control unit switches between a fluid state and a non-fluid state of the liquid by repeatedly stirring and stopping stirring by the stirring unit.

[0030] As a result, when the liquid is in a non-flowing state, an electron transfer reaction occurs between the electron carrier immobilized on the electrode and the target molecule, and a stable reaction field is easily formed. As a result, the activation efficiency of the target molecule is improved. In addition, by controlling the switching of the liquid between a flowing state and a non-flowing state, the activated target molecule is diffused from the vicinity of the electrode, and other target molecules in the liquid are easily moved to the vicinity of the electrode. As a result, more target molecules in the liquid can perform an electron transfer reaction with the electron carrier, and the efficiency of the electron transfer reaction between the target molecule and the electron carrier is improved. Furthermore, by switching the liquid between a flowing state and a non-flowing state, activation and diffusion of the target molecule can be repeatedly performed, so that the target molecule can be continuously activated. Therefore, according to the target molecule oxidation-reduction device, the target molecule can be efficiently activated in the entire reaction system (i.e., the liquid).

[0031] For example, in a target molecule oxidation-reduction device according to one embodiment of the present disclosure, the target molecule is NADP + may be also possible.

[0032] This produces NADPH as an active target substance, which can activate redox molecules, redox enzymes, redox proteins, and the like involved in various redox reactions.

[0033] For example, in a target molecule oxidation-reduction device according to an aspect of the present disclosure, the electrode may include a substrate containing gold.

[0034] This makes it possible to obtain an electrode with low chemical reactivity and resistance to corrosion. In addition, since gold has a high binding affinity for molecules having sulfur, nitrogen, or oxygen atoms, it is easy to modify the surface, thereby making it possible to obtain an electrode with functionality.

[0035] For example, in the target molecule oxidation-reduction device according to the embodiment of the present disclosure, the electron carrier may be a 4,4'-bipyridinium derivative, for example, 1-methyl-1'-hexyl-4,4'-bipyridinium.

[0036] In this way, by using a 4,4'-bipyridinium derivative as an electron carrier, the affinity of the electron carrier to the enzyme is increased. Therefore, the electron carrier can be used, for example, as a coenzyme involved in an oxidation-reduction reaction (e.g., NADP + ), but also easily interacts with enzymes and proteins. Furthermore, by using 1-methyl-1'-hexyl-4,4'-bipyridinium as an electron carrier, Electron carrier substrate fart This makes it easier to fix the

[0037] In addition, these comprehensive or specific aspects may be realized by a system, a method, an apparatus, an integrated circuit, a computer program, or a recording medium such as a computer-readable CD-ROM, or may be realized by any combination of a system, a method, an apparatus, an integrated circuit, a computer program, and a recording medium.

[0038] Hereinafter, the embodiment will be specifically described with reference to the drawings.

[0039] The embodiments described below are all comprehensive or specific examples. The numerical values, shapes, materials, components, the arrangement and connection of the components, steps, and the order of steps shown in the following embodiments are merely examples and are not intended to limit the scope of the claims. Furthermore, among the components in the following embodiments, components that are not described in an independent claim showing the highest concept are described as optional components. Furthermore, each figure is not necessarily a strict illustration. In each figure, substantially the same configuration is given the same reference numeral, and duplicated explanations may be omitted or simplified.

[0040] In each drawing, the explanation will be made by appropriately using mutually orthogonal X-axis, Y-axis, and Z-axis directions. In particular, the positive side of the Z-axis direction may be described as the upper side, and the negative side as the lower side.

[0041] In addition, in this disclosure, terms indicating the relationship between elements, such as parallel and perpendicular, terms indicating the shape of an element, such as rectangle, and numerical values ​​do not only indicate the strict meaning, but also include a substantially equivalent range, for example, a difference of about a few percent.

[0042] Also, in the drawings of this disclosure, dashed lines represent obscured surfaces and area boundaries.

[0043] (Embodiment) Hereinafter, the embodiment will be specifically described with reference to FIGS. 1 to 5. FIG.

[0044] [Target molecular redox machinery] [1. Overview] First, an overview of a target molecule oxidation-reduction device in an embodiment will be described with reference to Fig. 1. Fig. 1 is a diagram showing an example of the configuration of a target molecule oxidation-reduction device 100 in an embodiment.

[0045] In the target molecule oxidation-reduction device 100, when a voltage is applied to the electrodes while the liquid containing the target molecules is in a non-flowing state, electrons are transferred between the electron carrier immobilized on the electrodes and the target molecules, thereby oxidizing or reducing the target molecules. Then, by switching the liquid from a non-flowing state to a flowing state, the activated target molecules are diffused in the liquid. In this way, by repeatedly switching the flowing state of the liquid, the target molecules can be efficiently activated throughout the liquid.

[0046] In addition, a liquid being in a non-flowing state refers to, for example, a state in which the liquid is not being stirred or shaken (i.e., not being subjected to external forces such as shear force or vibration) and no movement such as fluctuations is observed on the liquid surface.

[0047] [2. Configuration] Next, the configuration of a target molecule oxidation-reduction device 100 according to an embodiment will be described with reference to FIGS.

[0048] The target molecule oxidation-reduction device 100 according to the embodiment includes an agitation unit 40 that agitates a liquid containing target molecules to create a fluid state, an electrode (cathode electrode 1) to which an electron carrier is fixed that oxidizes or reduces the target molecule by transferring electrons to and from the target molecule, a power source 20 that applies a voltage to the electrode, and a control unit 30 that controls the power source 20 and the agitation unit 40. The electrode to which the electron carrier is fixed (hereinafter, cathode electrode 1) is one component of the voltage application unit 10.

[0049] [Voltage application section] First, the voltage application unit 10 will be described with reference to Fig. 2. Fig. 2 is a perspective view of the voltage application unit 10 in the embodiment. The voltage application unit 10 transfers electrons to and from a target molecule via an electron carrier fixed to an electrode (cathode electrode 1). In this way, the transfer of electrons between the electron carrier and the target molecule causes the target molecule to be oxidized or reduced.

[0050] The voltage application unit 10 is, for example, a three-electrode cell including a cathode electrode 1 (also called a working electrode), a reference electrode 2, a counter electrode 3, a cell 4, a lid portion 5, terminals 6a, 6b, and 6c, and leads 7a, 7b, and 7c. The voltage application unit 10 may be, for example, a two-electrode cell including a working electrode (cathode electrode 1) and a counter electrode 3.

[0051] The cathode electrode 1 will be described with reference to Fig. 3. Fig. 3 is a cross-sectional view taken along line III-III in Fig. 2.

[0052] The cathode electrode 1 has a glass substrate 11, a titanium vapor-deposited layer 12 vapor-deposited on the glass substrate 11, a cathode substrate 13 formed on the titanium vapor-deposited layer 12, and a reaction layer 14 including an electron carrier immobilized on the cathode substrate 13.

[0053] The cathode electrode 1 is obtained by immobilizing a low molecular weight compound or an enzyme capable of activating a deactivated target molecule (so-called an inactive target molecule) on the cathode substrate 13 as an electron carrier (also called an electron mediator). The cathode substrate 13 may be a conductive substrate made of a conductive material. The conductive material may be, for example, a carbon material, a conductive polymer material, a semiconductor, or a metal. For example, the carbon material may be carbon nanotubes, ketjen black, glassy carbon, graphene, fullerene, carbon fiber, carbon fabric, or carbon aerogel. For example, the conductive polymer material may be polyaniline, polyacetylene, polypyrrole, poly(3,4-ethylenedioxythiophene), poly(p-phenylenevinylene), polythiophene, or poly(p-phenylene sulfide). For example, the semiconductor may be silicone, germanium, indium tin oxide (ITO), titanium oxide, copper oxide, or silver oxide. For example, the metal may be gold, platinum, silver, titanium, aluminum, tungsten, copper, iron, or palladium. The conductive material is not particularly limited as long as it is not decomposed by its own oxidation reaction. The thickness of the cathode substrate 13 is not particularly limited.

[0054] The electron carrier immobilized on the cathode substrate 13 is not particularly limited as long as it is a substance that allows electron transfer between the target molecule in the sample solution (also called liquid) and the cathode substrate 13 (the conductive substrate described above). Examples of the electron carrier include viologen compounds, bipyridine salt derivatives, quinones, and indophenols. The viologen compound is the common name for N,N'-disubstituted-4,4'-bipyridinium in which substituents are introduced into the two nitrogen atoms of the pyridine ring of 4,4'-bipyridine. The introduction of the substituents makes the ring nitrogen atom positively charged and functions as an electron carrier. The bipyridinium salt derivative may have two chloride ions or bromide ions as counter ions. Examples of viologen compounds include 4,4'-bipyridinium derivatives, such as 1,1'-dimethyl-4,4'-bipyridinium (methyl viologen), 1-methyl-1'-carboxylmethyl-4,4'-bipyridinium, 1,1'-dicarboxymethyl-4,4'-bipyridinium, 1-methyl-1'-aminoethyl-4,4'-bipyridinium, 1,1'-diaminoethyl-4,4'-bipyridinium, 1-methyl-1'-ethyl-4,4'-bipyridinium, and 1-methyl-1'-propyl-4,4'-bipyridinium. , 1-methyl-1'-butyl-4,4'-bipyridinium, 1-methyl-1'-pentylhexyl-4,4'-bipyridinium, 1-methyl-1'-hexyl-4,4'-bipyridinium, 1-methyl-1'-heptyl-4,4'-bipyridinium, 1-methyl-1'-octyl-4,4'-bipyridinium, 1-methyl-1'-nonyl-4,4'-bipyridinium, 1-methyl-1'-decyl-4,4'-bipyridinium, or a compound in which the methyl group at the 1-position of these compounds is replaced with an ethyl group. Among these, the electron carrier may be 1-methyl-1'-hexyl-4,4'-bipyridinium.

[0055] The reference electrode 2 is an electrode that does not react with components in the sample solution 9 and maintains a constant potential, and is used to control the potential difference between the cathode electrode 1 and the reference electrode 2 to a constant value using a power source 20. Here, the reference electrode 2 is a silver / silver chloride electrode. The counter electrode 3 is, for example, a platinum electrode.

[0056] Here, the arrangement of the above three electrodes will be described with reference to Fig. 4. Fig. 4 is a cross-sectional view taken along line IV-IV in Fig. 2. As shown in Fig. 4, the cathode electrode 1, the reference electrode 2, and the counter electrode 3 are arranged in a cylindrical cell 4 so as to surround the center of the cell 4 in the vertical direction. A stirrer 8 is arranged at the bottom of the cell 4. A reaction layer containing an electron carrier fixed to the cathode electrode 1 is arranged facing the center of the vertical axis of the cell.

[0057] In this embodiment Targeted Molecular Redox Apparatus 100 The device comprises a cathode electrode 1 having a low molecular weight compound and an enzyme immobilized on its surface as electron carriers capable of reactivating target molecules, an anode electrode as a counter electrode 3, a reference electrode 2, and a stirrer 8 that is driven by controlling the flowing and non-flowing states of the sample solution to improve reaction efficiency, and the surface area of ​​the cathode electrode 1 (working electrode) may be sufficiently larger than that of the anode electrode (counter electrode 3).

[0058] The cell 4 is a holding section that holds a sample solution 9 in which an inactive target molecule is present. A stirrer 8 that stirs the sample solution 9 is disposed in the cell 4. Although an example in which the cell 4 is cylindrical is shown in Figs. 1 and 2, the shape of the cell 4 is not limited to this. The stirrer 8 will be described later.

[0059] An inactive target molecule is, for example, NADP + The inactive target molecule is NAD + or an inactive ferredoxin.

[0060] 1 and 2 again, the lid 5 is provided with terminals 6a, 6b, and 6c for electrically connecting the cathode electrode 1, the reference electrode 2, and the counter electrode 3 to the power source 20, respectively. Leads extend from each terminal, and the terminals electrode Connected to .mosquito The cathode electrode 1 is connected to the terminal 6a via the lead 7a. The reference electrode 2 is connected to the terminal 6b via the lead 7b. The counter electrode 3 is connected to a terminal 6c via a lead 7c.

[0061] [power supply] Next, the power source 20 will be described with reference to Fig. 5. Fig. 5 is a diagram showing an example of a functional configuration of the target molecule oxidation-reduction device 100 according to the embodiment.

[0062] The power supply 20 applies a voltage to the electrode (cathode electrode 1). More specifically, the power supply 20 applies a voltage between the cathode electrode 1 of the voltage application unit 10 and the counter electrode 3 in accordance with a control signal output from the control unit 30, and controls the potential between the cathode electrode 1 and the reference electrode 2 to a predetermined value.

[0063] As shown in FIG. 5, the power supply 20 includes, for example, an acquisition unit 21, an information processing unit 22, a voltage control unit 23, and an output unit 24.

[0064] The acquiring unit 21 acquires a control signal output from the control unit 30, and outputs the acquired control signal to the information processing unit 22. The acquiring unit 21 may also acquire data such as the potential of each electrode in the voltage application unit 10 and the value of a current flowing through the sample solution 9. In this case, the output unit 24 outputs the data acquired by the acquiring unit 21 to the control unit 30. The processing of the data in the control unit 30 will be described later.

[0065] The information processing unit 22 processes the information acquired by the acquisition unit 21. For example, when the information processing unit 22 acquires a control signal from the acquisition unit 21, it outputs the acquired control signal to the voltage control unit 23. When the voltage control unit 23 starts applying a voltage to each electrode of the voltage application unit 10, the information processing unit 22 acquires data such as the potential of each electrode in the voltage application unit 10 acquired from the acquisition unit 21 and the current value flowing through the sample solution 9, and derives a voltage to be applied to the cathode electrode 1 based on the acquired data. Then, the information processing unit 22 outputs a control signal to the voltage control unit 23 for controlling the voltage of the cathode electrode 1 with the derived voltage.

[0066] The voltage control unit 23 applies a voltage to each electrode of the voltage application unit 10 based on the control signal output from the information processing unit 22 .

[0067] Although FIG. 1 shows an example in which the power source 20 and the control unit 30 are separate entities, the power source 20 may include the control unit 30.

[0068] [Mixing section] The stirring unit 40 stirs the liquid (here, sample solution 9) containing the inactive target molecules to make it flow. More specifically, the stirring unit 40 controls the operation of the motor 43 according to a control signal output from the control unit 30, thereby controlling the rotation speed and rotation time of the stirrer 8 set in the voltage application unit 10.

[0069] As shown in FIG. 5, the stirring unit 40 includes, for example, an acquisition unit 41, a stirring control unit 42, and a motor 43.

[0070] The acquisition unit 41 acquires a control signal output from the control unit 30, and outputs the acquired control signal to the stirring control unit .

[0071] The stirring control unit 42 processes the information acquired by the acquisition unit 41. For example, when the stirring control unit 42 acquires a control signal from the acquisition unit 41, it derives control conditions for the motor 43 based on the acquired control signal and controls the operation of the motor 43. Specifically, the stirring control unit 42 controls the rotation speed, rotation time, etc. of the motor 43 to control the movement of the stirrer 8 (i.e., the rotation speed and rotation time).

[0072] 1 shows an example in which the stirring unit 40 is separate from the voltage application unit 10, but the stirring unit 40 may be integrated with the voltage application unit 10. In this case, the stirring unit 40 is disposed, for example, in the lid 5 of the voltage application unit 10, and the stirring bar 8 may be, for example, a stirring blade that is detachable from the lid 5.

[0073] [Control Unit] The control unit 30 performs information processing for controlling the application of voltage from the power source 20 and the movement of the motor 43 of the stirring unit 40. The control unit 30 is realized by, for example, a processor, a microcomputer, or a dedicated circuit. In FIG. 1, the control unit 30 is shown as an example being a computer device.

[0074] The control unit 30 includes, for example, an acquisition unit 31, an information processing unit 32, a storage unit 33, and an output unit .

[0075] The acquisition unit 31 acquires, for example, information regarding instructions input by a user (hereinafter, instruction information), as well as data such as the potential of each electrode in the voltage application unit 10 and the current value flowing through the sample solution 9, and outputs the acquired instruction information and data to the information processing unit 32.

[0076] The information processing unit 32 derives conditions for applying a voltage to each electrode of the voltage application unit 10 (also referred to as voltage application conditions) and liquid flow conditions such as switching of the flow state and flow speed of the sample solution 9, based on, for example, the instruction information acquired by the acquisition unit 31. The instruction information may be, for example, the type of target molecule, the amount of the sample solution 9, the completion time of the process, or the completion time.

[0077] Furthermore, the information processing unit 32 may derive the reduction rate of the target molecule in the sample solution based on the data acquired by the acquisition unit 31, for example, and change the voltage application conditions and the liquid flow conditions according to the derived reduction rate. For example, the information processing unit 32 may change the voltage application time among the voltage application conditions derived based on the instruction information, or may change the voltage applied to each electrode. For example, the information processing unit 32 may change the timing of switching the flow state of the sample solution among the liquid flow conditions derived based on the instruction information, or may change the flow rate. This allows the control unit 30 to re-derive (i.e., change) the voltage application conditions and the liquid flow conditions derived based on the instruction information according to the reduction state (reduction rate) of the target molecule, so that the target molecule in the sample solution can be reduced more efficiently.

[0078] Furthermore, the information processing unit 32 may derive a control signal for controlling the voltage application of the power source 20 under the voltage application conditions, and may derive a control signal for controlling the operation of the motor 43 under the liquid flow conditions. The voltage application conditions and the liquid flow conditions may be derived based on the instruction information or data acquired by the acquisition unit 31 as described above, or may be set in advance by the user. The information processing unit 32 outputs these control signals to the output unit 34.

[0079] The output unit 34 acquires the control signal derived by the information processing unit 32 and outputs it to the power source 20 and the stirring unit 40 .

[0080] The storage unit 33 stores the data acquired by the acquisition unit 31, computer programs executed by the control unit 30 (for example, application programs for controlling the power source 20), and the like.

[0081] [3. Operation] Next, the operation of the target molecule oxidation-reduction device 100 according to the embodiment will be specifically described with reference to Fig. 6 in addition to Fig. 1 to Fig. 5. Fig. 6 is a flow chart showing an example of the operation of the target molecule oxidation-reduction device 100 according to the embodiment.

[0082] Although not shown in the figure, a preparation step before operating the target molecule oxidation-reduction device 100 will be described first. For example, the preparation step may be performed by a user. In the preparation step, a sample solution 9 is first prepared. The user introduces the sample solution 9 containing an inactive target molecule into the cell 4 of the voltage application unit 10.

[0083] Next, the user inserts and sets the electrodes into the sample solution 9. The electrodes are a cathode electrode 1, a reference electrode 2, and a counter electrode 3. The cathode electrode 1 is connected to a lead 7a extending from a terminal 6a arranged in the lid portion 5, the reference electrode 2 is connected to a lead 7b extending from a terminal 6b arranged in the lid portion 5, and the counter electrode 3 is connected to a lead 7c extending from a terminal 6c arranged in the lid portion 5.

[0084] Next, the user inputs information regarding instructions such as the type of target molecule, the amount of sample solution, the time required to complete the process, and the completion time into the target molecule oxidation-reduction device 100a.

[0085] In the above preparation step, the user introduces the sample solution 9 containing the target molecules into the cell 4, but the target molecule oxidation-reduction device 100 may introduce the sample solution 9 into the cell 4. That is, although an example in which the user performs the above preparation step has been described, the target molecule oxidation-reduction device 100 may execute the preparation step. In this case, the target molecule oxidation-reduction device 100 may further include an introduction section (not shown), a recovery section (not shown), an inlet (not shown), and an outlet (not shown). For example, the introduction section may introduce the sample solution 9 containing the inactive target molecules into the cell 4 from an inlet provided in the cell 4. Also, for example, the recovery section may reduce the inactive target molecules to recover the sample solution 9 containing the active target molecules from an outlet provided in the cell 4 to the outside of the cell 4.

[0086] Next, the operation of the target molecule oxidation-reduction device 100 will be described. When the user inputs instruction information, the control unit 30 sets the conditions for applying voltage to each electrode of the voltage application unit 10 and the liquid flow conditions (step S101). In setting the conditions, the control unit 30 derives the voltage application conditions and the liquid flow conditions based on the input instruction information. Then, the control unit 30 outputs a control signal to the power source 20 for controlling the voltage application of the power source 20 under the derived voltage application conditions. In addition, the control unit 30 outputs a control signal to the stirring unit 40 for controlling the operation of the stirring unit 40 under the derived liquid flow conditions. Note that in step S101, the control unit 30 may acquire the program number and set the voltage application conditions and the liquid flow conditions by selecting a program number associated with a set of the voltage application conditions and the liquid flow conditions by the user.

[0087] Next, when the power source 20 and the stirring unit 40 acquire the control signal output from the control unit 30, they respectively start applying a voltage to the electrodes and controlling the motor 43 in accordance with the control signal (step S102). 30starts voltage application, and the stirring unit 40 controls to stop the motor 43 (i.e., to put the sample solution 9 in a non-flowing state) (step S103). In step S103, for example, the power source 20 applies a voltage between the cathode electrode 1 and the counter electrode 3 of the voltage application unit 10, and controls the potential between the cathode electrode 1 and the reference electrode 2 to a predetermined value. The predetermined value may be determined according to the combination of the electron carrier and the target molecule used. At this time, the stirring unit 40 does not operate the motor 43, or rotates the motor 43 at a speed that does not cause fluctuations on the liquid surface. As a result, the inactive target molecules in the sample solution 9 receive electrons via the electron carrier fixed to the cathode electrode 1 while the sample solution 9 is in a non-flowing state, and are reduced to active target molecules. This step is also called the first step.

[0088] Next, the stirring unit 40 controls the motor 43 to rotate at a predetermined rotation speed, and stirs the sample solution 9 with the stir bar 8 (step S104). As a result, the target molecules activated in step S103 (active target molecules) are diffused into the sample solution 9, and the inactive target molecules in the sample solution 9 move to the vicinity of the cathode electrode 1. In this step, the stirring unit 40 switches between stirring and stopping stirring based on the liquid flow conditions, and switches the sample solution 9 from a non-flowing state to a flowing state. At this time, the stirring unit 40 controls the rotation operation of the motor 43 and controls the rotation speed and time of the stir bar 8. As a result, the sample solution 9 in the cell 4 is stirred and brought into a flowing state, and the active target molecules present in the vicinity of the cathode electrode 1 are diffused into the sample solution 9. At this time, the inactive target molecules in the sample solution 9 are more likely to move to the vicinity of the cathode electrode 1. Note that in step S104, the power source 20 may control to stop the voltage application, or may control to continue the voltage application.

[0089] The power source 20 and the stirring unit 40 sequentially repeat the processes of steps S103 and S104 (not shown).

[0090] For example, the execution time of step S103 may be longer than the execution time of step S104, and the ratio thereof may be 10 to 100:1. More specifically, the execution time of step S103 is 30 minutes or more and 90 minutes or less, and the execution time of step S104 is 1 minute or more and 2 minutes or less. As a result, in step S103, a larger number of inactive target molecules are reduced to active target molecules, and the active target molecules in the vicinity of the cathode electrode 1 are diffused into the sample solution 9 by stirring, and new inactive target molecules move to the vicinity of the cathode electrode 1. By repeating these processes, the activation efficiency (i.e., reduction efficiency) of the inactive target molecules is improved throughout the sample solution 9.

[0091] Next, the control unit 30 judges whether the process under the set conditions has been completed (step S105). The set conditions are, for example, the period (time) of voltage application, the number of times voltage is applied (e.g., pulse voltage), or the number of times the flow state of the sample solution 9 is switched. If the control unit 30 judges that the process under the set conditions has not been completed (No in step S105), it causes the power source 20 to continue applying voltage and causes the stirring unit 40 to continue the operation (also simply referred to as operation) based on the liquid flow conditions (step S106). Then, steps S103 and S104 are repeated until the next judgment (step S105) is made.

[0092] On the other hand, when the control unit 30 determines that the process under the set conditions is completed (Yes in step S105), it causes the power source 20 to stop applying voltage and causes the stirring unit 40 to stop operating (step S107). This completes the activation of the inactive target molecules in the sample solution 9. EXAMPLES

[0093] The method for oxidizing and reducing a target substance according to the present disclosure will be specifically described below with reference to examples. However, the following examples are merely examples, and the present disclosure is in no way limited to the following examples.

[0094] In the following Examples and Comparative Examples, an inactive target molecule (hereinafter also simply referred to as a target molecule) is an oxidized nicotinamide adenine dinucleotide phosphate (NADP + ) was used.

[0095] Example 1 (Preparation of target molecule solution) The target molecule solution is NADP + was dissolved in phosphate buffered saline (PBS) at pH 7.4 to prepare a concentration of 1.0 mmol / L.

[0096] (Preparation of cathode electrode) Titanium and gold were deposited in this order on a glass substrate to prepare a gold substrate. The gold substrate was then modified with 4-mercaptopyridine to prepare a 4-mercaptopyridine-modified gold substrate. Next, 1-methyl-1' - Hexyl-4,4' - Bipyridinium was immobilized to obtain the cathode electrode 1. - Hexyl-4,4' - Bipyridinium is NADP + to reduce it to NADPH (in other words, NADP + It is an electron carrier that reactivates

[0097] (Application of voltage to target molecule solution) A target molecule solution (1.0 mM NADP +-PBS solution) was introduced and the electrodes were set. The electrodes used were three-electrode system electrodes, with the prepared cathode electrode 1 as the working electrode, a Pt (platinum) electrode as the counter electrode, and an Ag / AgCl (silver / silver chloride) electrode as the reference electrode. Next, a stirrer was placed in the target molecule solution, and a voltage was applied to the target molecule solution while rotating the stirrer at a predetermined rotation speed (rpm). Specifically, the non-flowing and flowing states of the target molecule solution were switched by controlling the movement of the stirrer with two types of rotation control, stopping and rotating, while applying a predetermined voltage to the target molecule solution. This allowed the switching between the non-flowing and flowing states of the target molecule solution to be adjusted. The time for which a voltage was applied to the target molecule solution in the non-flowing state was sufficiently longer than the time for which a voltage was applied in the flowing state. A predetermined voltage was continuously applied to the target molecule solution while sequentially repeating these two types of control.

[0098] (Confirmation of reactivation of target molecules) After the voltage application to the target molecule solution was completed, the target molecule solution was sampled from around the working electrode (cathode electrode), the counter electrode, and the reference electrode. The absorbance (hereinafter simply referred to as absorbance) of the sampled target molecule solution in the wavelength range including 340 nm was then measured. The measurement was performed using a 1 mm cell. 340 nm is the absorption wavelength specific to NADPH.

[0099] Figure 7 shows the measurement results of the absorbance of the target molecule solution sampled around the working electrode (cathode electrode) and the absorbance of the target molecule solution sampled around the counter electrode located furthest from the working electrode. As shown in Figure 7, an absorption peak was observed at 340 nm in both the target molecule solution around the working electrode (near the cathode electrode in the figure) and the target molecule solution around the counter electrode (far from the cathode electrode in the figure). The absorbance of the target molecule solution was 0.08 around the working electrode and 0.07 around the counter electrode furthest from the working electrode. This shows that the target molecule, NADP + It was confirmed that NADPH was produced by reduction of NADPH.

[0100] In addition, the average value of the absorbance at 340 nm of the target molecule solution around the triode was calculated as the absorbance of the entire target molecule solution. The calculation results are shown in Figure 8. As shown in Figure 8, in Example 1, the absorbance of the entire target molecule solution after voltage application was 0.072.

[0101] Comparative Example 1 Comparative Example 1 was carried out under the same conditions as Example 1, except that the stirrer was constantly rotating (that is, the target molecule solution was constantly in a flowing state).

[0102] Figure 9 shows the measurement results of the absorbance of the target molecule solution sampled around the working electrode (cathode electrode) and the absorbance of the target molecule solution sampled around the counter electrode located furthest from the working electrode. As shown in Figure 9, no absorption peak was observed at 340 nm in either the target molecule solution around the working electrode (near the cathode electrode in the figure) or the target molecule solution around the counter electrode (farther from the cathode electrode in the figure). This shows that the target molecule, NADP + It was confirmed that no refunds were made.

[0103] In addition, the average value of the absorbance of the target molecule solution around the triode was calculated as the absorbance of the entire target molecule solution. The calculation results are shown in Figure 8. As shown in Figure 8, in Comparative Example 1, the absorbance of the entire target molecule solution after voltage application was 0.056.

[0104] Comparative Example 2 Comparative Example 2 was carried out under the same conditions as Example 1, except that the stirrer was not rotated.

[0105] Figure 10 shows the measurement results of the absorbance of the target molecule solution sampled around the working electrode (cathode electrode) and the absorbance of the target molecule solution sampled around the counter electrode located furthest from the working electrode. As shown in Figure 10, the target molecule solution around the working electrode (near the cathode electrode in the figure) showed an absorption peak at 340 nm, but the target molecule solution around the counter electrode (far from the cathode electrode in the figure) did not show an absorption peak at 340 nm. This indicates that the target molecule NADP +It was confirmed that NADPH was produced by reduction of NADPH.

[0106] In addition, the average value of the absorbance at 340 nm of the target molecule solution around the triode was calculated as the absorbance of the entire target molecule solution. The calculation results are shown in Figure 8. As shown in Figure 8, in Comparative Example 2, the absorbance of the entire target molecule solution after voltage application was 0.063.

[0107] (Consideration) 8, in Comparative Example 1, the absorbance of the entire target molecule solution was lower than that of Example 1 and Comparative Example 2. As in Comparative Example 1, when a voltage was applied to the target molecule solution while the stirring bar was rotated to stir the target molecule solution (i.e., the target molecule solution was in a fluid state), the target molecule NADP + However, the electron carrier cannot remain around the working electrode (cathode electrode) for the time required for the electron transfer reaction. Therefore, it is considered that the electron transfer reaction between the electron carrier fixed to the working electrode and the target molecule is difficult to occur, and the efficiency of electron transfer from the electron carrier to the target molecule is poor.

[0108] 8, the absorbance of the entire target molecule solution in Comparative Example 2 was higher than that in Comparative Example 1. When a voltage was applied to the target molecule solution without rotating the stirrer (i.e., the target molecule solution was not stirred and was in a non-flowing state) as in Comparative Example 2, the target molecule (NADP + ) can remain around the working electrode for the time required for the electron transfer reaction. Therefore, it is considered that the efficiency of electron transfer from the electron carrier fixed to the working electrode to the target molecule is increased. On the other hand, since the absorbance around the counter electrode away from the working electrode is similar to that of Comparative Example 1, it was found that the electron transfer reaction only occurs around the working electrode. Therefore, it is considered that a certain degree of stirring is necessary to improve the reaction efficiency.

[0109] In addition, as shown in FIG. 8, Example 1 had the highest absorbance at 340 nm for the entire target molecule solution. TurningThe two types of control, stopping and rotating, were alternately repeated at a specified time interval (stop time > rotation time). Therefore, it is considered that while the stirrer is stopped (i.e., the target molecule solution is not flowing), an electron transfer reaction occurs between the electron carrier on the working electrode and the target molecule, and while the stirrer is rotating (i.e., the target molecule solution is flowing), the activated target molecule around the working electrode is diffused throughout the target molecule solution. This demonstrated that the electron transfer reaction between the electron carrier and the target molecule occurred efficiently throughout the entire target molecule solution.

[0110] From the above, it was confirmed that the activation efficiency of the target molecules is improved by making the time during which the target molecule solution is applied in a non-flowing state longer than the time during which the target molecule solution is in a flowing state.

[0111] The above describes the target molecule oxidation-reduction method and the target molecule oxidation-reduction device according to the present disclosure based on the embodiments, but the present disclosure is not limited to these embodiments. As long as it does not deviate from the gist of the present disclosure, various modifications conceivable by a person skilled in the art to the embodiments and other forms constructed by combining some of the components in the embodiments are also included in the scope of the present disclosure. [Industrial Applicability]

[0112] INDUSTRIAL APPLICABILITY According to the present disclosure, an electron carrier can be repeatedly activated, and therefore the present disclosure can be widely used in any field that utilizes an electron transfer reaction via an electron carrier. [Explanation of symbols]

[0113] 1. Cathode electrode 2 Reference pole 3. Opposite 4 Cell 5 Lid 6a, 6b, 6c terminals 7a, 7b, 7c Lead 8 Stirring bar 9. Sample solution 10 Voltage application section 11 Glass substrate 12 Titanium deposition layer 13 Cathode substrate 14 Reaction layer 20 Power supply 21 Acquisition Department 22 Information Processing Section 23 Voltage control section 24 Output section 30 Control section 31 Acquisition Department 32 Information Processing Section 33 Storage section 34 Output section 40 Mixing section 41 Acquisition Department 42 Mixing control section 43 Motor 100 Targeted Molecular Redox Machine

Claims

1. a first step of oxidizing or reducing the target molecule by making a liquid containing the target molecule non-flowing and transferring electrons between the target molecule and an electron carrier fixed to an electrode connected to an external power source outside the liquid; A second step of bringing the liquid into a fluidized state; Including, The first step and the second step are sequentially and repeatedly performed. Methods for the oxidation and reduction of target molecules.

2. In the second step, the liquid is made into a fluid state by stirring or shaking the liquid. The method for oxidizing and reducing a target molecule according to claim 1.

3. The execution time of the first step is longer than the execution time of the second step. A method for oxidizing and reducing a target molecule according to claim 1 or 2.

4. The ratio of the execution time of the first step to the execution time of the second step is 10 to 100:1; The method for oxidizing and reducing a target molecule according to claim 3.

5. The execution time of the first step is 30 minutes or more and 90 minutes or less, The execution time of the second step is 1 minute or more and 2 minutes or less. The method for oxidizing and reducing a target molecule according to claim 4.

6. The target molecule is NADP ＋ That is, A method for oxidizing and reducing a target molecule according to any one of claims 1 to 5.

7. The electrode has a substrate comprising gold. The method for oxidation-reduction of a target molecule according to any one of claims 1 to 6.

8. The electron carrier is a 4,4'-bipyridinium derivative. A method for oxidizing and reducing a target molecule according to any one of claims 1 to 7.

9. The electron carrier is 1-methyl-1'-hexyl-4,4'-bipyridinium. The method for oxidizing and reducing a target molecule according to claim 8.

10. The voltage application from the external power source is performed in the first step. The method for oxidizing and reducing a target molecule according to any one of claims 1 to 9.

11. A stirring unit that stirs the liquid containing the target molecules to make it into a fluid state; an electrode having an electron carrier immobilized thereon, which oxidizes or reduces the target molecule by donating or receiving electrons between the electrode and the target molecule; A power source that applies a voltage to the electrodes; A control unit that controls the power source and the stirring unit; Equipped with The control unit switches between a flowing state and a non-flowing state of the liquid by repeatedly causing the stirring unit to stir and stop stirring. Targeted molecular redox machinery.

12. The target molecule is NADP ＋ That is, The target molecule redox device according to claim 11.

13. The electrode has a substrate comprising gold. The target molecule redox device according to claim 11 or 12.

14. The electron carrier is a 4,4'-bipyridinium derivative. The target molecule oxidation-reduction device according to any one of claims 11 to 13.

15. The electron carrier is 1-methyl-1'-hexyl-4,4'-bipyridinium. The target molecule redox device according to claim 14.

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