JPH10152306A - Formation of superoxide anion radical and apparatus therefor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To artificially enable electrochemical formation of a superoxide anion radical as a kind of active oxygen in excellent reproducibility, by immersing a discharge tube in which a mixed gas is sealed in water and inducing glow discharge. SOLUTION: A discharge tube in which a mixed gas is sealed is immersed in water, a high-voltage negative pulse signal is impressed to electrodes in the discharge tube to induce a glow discharge. A superoxide anion radical is more effectively formed by making the ratio of nitrogen and argon of the mixed 8:2 and adjusting the pressure of the discharge tube to 4.2mmHg, the peak value of the high-voltage negative pulse signal to 15KV and the frequency to 100Hz. This apparatus for producing a superoxide anion radical has a high- voltage generating circuit 20 for forming a high-voltage negative pulse signal, and a discharge electrode 12 for impressing the high-voltage negative pulse signal and is equipped with a discharge tube 10 having a glow discharge part 13 immersed in water.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a superoxide anion radical which is a kind of active oxygen.
The present invention relates to a method and an apparatus for electrochemically producing ion radicals.

[0002]

2. Description of the Related Art Hydroxyl radical as active oxygen,
Four types of hydrogen peroxide, singlet oxygen, and superoxide anion radical are known, and active oxygen produced in the body in appropriate amounts is necessary and beneficial to the body for self-defense, When it is produced, it causes many disorders to the body and causes various diseases. Among active oxygens, a superoxide anion radical in which one electron is contained in oxygen is represented by the following chemical formula.

[0003]

Embedded image Such a superoxide anion radical is an important one which has a direct effect on the activity of a cell, particularly among active oxygens, and in combination with the formation of the superoxide anion radical, Research on substances that scavenge radicals is also being vigorously conducted. As a system for experimentally generating a superoxide anion radical, an enzyme system such as xanthine oxidase has been widely used. As a method for generating active oxygen, a method of irradiating water with radiation is known.

[0004]

However, in the method for producing a superoxide anion radical using an enzyme system such as xanthine oxidase, the superoxide anion radical itself is eliminated or the enzyme is used. It was not possible to distinguish whether the system inhibited the generation of superoxide anion radicals. In other words, it is not known whether or not a superoxide anion radical has been generated, and the production method was extremely insufficient. This method of producing a superoxide anion radical using an enzyme system has a problem in reproducibility due to the enzymatic reaction, and it cannot always be obtained in a stable state. Further, in the method of irradiating water with radiation, there is a problem in handling dangerous radiation itself, and the generated active oxygen cannot be taken out for each type. In other words, in the method of irradiating water, various active oxygens are generated at the same time,
There is a disadvantage that only the superoxide anion radical cannot be selectively produced.

It is well known that the superoxide anion radical has a significant effect on human health, and it is known that the superoxide anion radical alone is used for research and drug development. Therefore, it is strongly desired that the compound be produced constantly and reproducibly.

The present invention has been made in view of the above circumstances, and an object of the present invention is to produce a superoxide anion radical having a particularly important significance among active oxygens artificially and reproducibly. It is to provide a method and an apparatus for electrochemical generation.

[0007]

SUMMARY OF THE INVENTION The present invention relates to a method for producing a superoxide anion radical, and an object of the present invention is to immerse a discharge tube filled with a mixed gas in water and to form an electrode in the discharge tube. Apply a high-voltage negative pulse signal to
It is achieved by inducing a discharge. By setting the mixture gas to a mixture ratio of nitrogen and argon of 8: 2 and the pressure of the discharge tube to 4.2 mmHg, the peak value of the high-voltage negative pulse signal is further reduced to 15 KV and the frequency is set to 1
By setting the frequency to 00 Hz, it can be more effectively achieved.

Further, the present invention relates to a device for generating a superoxide anion radical, and the object of the present invention is to provide a high voltage generating means for generating a high voltage negative pulse signal, and a high voltage generating means for applying the high voltage negative pulse signal. And a discharge tube having a glow discharge portion immersed in water. The peak value, frequency, and duty ratio of the high-voltage negative pulse signal are variable, and can be more effectively achieved by setting the peak value of the high-voltage negative pulse signal to 15 KV and the frequency to 100 Hz. .

[0009]

FIG. 1 shows the principle of the present invention. A water tank 1 is filled with water (for example, distilled water) 2, and a discharge tube 10 is immersed in the water 2. Discharge tube 10
Inside, a mixed gas of nitrogen and argon (8: 2) is sealed at a pressure of 4.2 mmHg, and has a ground electrode 11 and a discharge electrode 12 and a discharge part 13.
The ground electrode 11 is grounded with a platinum wire, and the discharge electrode 12 is supplied from a high voltage generating circuit 20 with a high voltage negative pulse signal NS (pulse width τ) having a peak value (peak value) of 15 KV and a frequency of 100 Hz.
1) is applied. The discharge tube is (1) a glass tube filled with decompressed air or gas covered with an electrode, and (2) a discharge tube filled with electrodes in a glass tube filled with decompressed air or gas. (Shown in FIG. 1), (3) a glass tube in which depressurized air or gas is sealed, and a metal deposition electrode formed on the inner wall of the glass tube, (4) a glass plate, a metal foil or a metal net made of glass or resin. What coated the insulator can be used.

In such a configuration, when a high voltage negative pulse signal NS having a peak value of 15 KV and a frequency of 100 Hz is applied from the high voltage generation circuit 20 to the discharge electrode 12 of the discharge tube 10,
A glow discharge is induced in the discharge unit 13. When a glow discharge is induced by a negative voltage, a charge addition effect is generated by a negative charge e ^{− on} water 2, and a superoxide anion radical is generated.

Here, experimental results will be described. The above glow discharge was performed on 4 ml of distilled water, and 200 μl of distilled water was taken out as a sample at intervals of 5 minutes after the discharge, and immediately 100 μM MCLA (2-methyl-p-methoxy) was taken out.
-3,7-dihydroimidazo [1,2-a] pyradin-3-one)
0 μl was added, and the amount of luminescence was detected with a MCLA chemiluminescence detector. It is known that MCLA specifically reacts with a superoxide anion radical in an aqueous solution to emit light, and hardly reacts with other substances (for example, Minoru Nakano,
Hirokazu Kimura, "Method for Measuring SOD Activity by Chemiluminescence," 1990, edited by Shunichi Yoshikawa, "Activated Enzymes and Luminescence", 1990.
Published by The Japan Medical Museum). As a result of detecting the amount of light emitted from each of the samples by the MCLA chemiluminescence detector, as shown in FIG. 2, the amount of MCLA chemiluminescence increased almost in proportion to the discharge time. This is because of the induction of glow discharge,
This proves that an oxide anion radical has been generated. This is because MCLA reacts only with the superoxide anion radical and emits light.

Further, in order to confirm that the change in the amount of chemiluminescence of MCLA shown in FIG. 2 is based on a superoxide anion radical, an antioxidant known as a substance for removing excess active oxygen was used. Of superoxide dismutase (SOD)
It was confirmed that light emission was suppressed or restricted. The graph of FIG. 3 shows the result. Test zone # 1 was distilled water 30 minutes after discharge, test zone # 2 was a 0.1 ng / ml SOD aqueous solution 30 minutes after discharge, and test zone # 3 was 10 ng / ml 30 minutes after discharge. Test solution #
Reference numeral 4 denotes a 1 μg / ml SOD aqueous solution 30 minutes after discharge, and test section # 5 denotes distilled water before discharge. Test plot # 1 was discharged into 4 ml of distilled water for 30 minutes as described above, and test plots # 2- # 4 were each 0.1 ng / ml.
SOD aqueous solution, 10 ng / ml SOD aqueous solution, 1 μg /
The solution was discharged for 30 minutes to the aqueous solution of SOD for 30 minutes by the above-mentioned method.
M MCLA was added, and the amount of luminescence was detected by a MCLA chemiluminescence detector. As a result, the amount of chemiluminescence is SO
D revealed that it was suppressed as in test plots # 2- # 4, indicating that the chemiluminescence of MCLA by glow discharge was due to the superoxide anion radical.

FIG. 4 shows a specific example of the configuration of the high-voltage generation circuit 20, in which a DC voltage (for example, +12 V) is applied to a charging circuit 21, a voltage detection circuit 22, and a trigger pulse generation circuit 23.
, And the charging circuit 21 boosts the voltage based on the applied voltage, and increases the main capacitor C to a set voltage (for example, +100 V).
Charge 1. The auxiliary capacitor C2 is connected to the main capacitor C
1 is connected in parallel with a switch 24 via a switch 24, and the time constant of charging or discharging is changed by turning on / off the switch 24. Voltage detection circuit 2
2 always detects the charging voltage of the main capacitor C1,
When the charging voltage of the main capacitor C1 reaches the set voltage, the operation of the charging circuit 21 is stopped, and the trigger pulse TG is sent from the trigger pulse generation circuit 23 to the thyristor 25.
Enter The thyristor 25 conducts when the trigger pulse TG is input, the charging voltage of the main capacitor C1 is discharged at a high speed, a current also flows through the primary coil of the step-up transformer 26, and a current also flows through the secondary coil by electromagnetic induction. . When the charging voltage of the main capacitor C1 is discharged, the charging operation is started. By repeating such charging and discharging, a pulse signal is applied to the primary coil of the step-up transformer 26, and the voltage is also boosted from the secondary coil. The output pulse signal is output.

The turn ratio of the step-up transformer 26 is 1: 150.
And the winding polarity is reversed,
The voltage pulse of +100 V on the primary coil side is output as a voltage pulse of -15 KV on the secondary coil side. The pulse output is applied to the discharge tube 10 as a high voltage negative pulse signal NS via a diode D1, and is also applied to a bleeder resistor R. The discharge current of the main capacitor C1 continues to attenuate even after the voltage of the main capacitor C1 becomes zero due to the back electromotive force due to the inductance of the step-up transformer 26, but finally falls below the holding current specific to the thyristor 25, which is turned off. Transition to and stop. At this time, on the secondary side of the step-up transformer 26, a positive kickback voltage appears due to the stop of the primary side current.
And is not transmitted to the discharge tube 10. Also, as shown in the figure, a flywheel diode D2
Can also quickly control the kickback voltage.

In such a high voltage generation circuit 20,
The peak value -Ao of the high-voltage negative pulse signal NS changes depending on the charging saturation voltage of the main capacitor C1 when the turn ratio of the step-up transformer 26 is constant. Therefore, the voltage detection circuit 2
By making the set voltage of 2 variable, the peak value -Ao of the high-voltage negative pulse signal NS can be easily changed. or,
The pulse width τ1 of the output high voltage negative pulse signal NS is
Since it is mainly determined by the capacitance of the main capacitor C1 and the inductance of the step-up transformer 26, it can be changed by, for example, turning on the switch 24 and connecting the auxiliary capacitor C2 in parallel. Further, the repetition period (frequency) τ1 + τ2 of the high-voltage negative pulse signal NS can be changed by adjusting the trigger pulse TG from the trigger pulse generation circuit 23.

[0016]

As described above, according to the present invention, a superoxide anion radical can be easily produced electrochemically, and a chemical reaction relating to a superoxide anion radical in active oxygen can be achieved. It will make a great contribution to biochemical and medical research. Further, since it can be manufactured relatively easily and inexpensively as a device for generating a superoxide anion radical, it is useful as a research instrument for active oxygen.

[Brief description of the drawings]

FIG. 1 is a configuration diagram for explaining the principle of the present invention.

FIG. 2 is a diagram showing chemiluminescence of MCLA by glow discharge.

FIG. 3 Generation of superoxide anion radical and S
It is a figure showing an example of an experiment of erasure by OD.

FIG. 4 is a circuit connection diagram showing a specific configuration example of a high voltage generation circuit.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Water tank 2 Water 10 Discharge tube 11 Ground electrode 12 Discharge electrode 13 Discharge part 20 High voltage generation circuit

Claims (5)

[Claims] A superoxide anion radical is generated by immersing a discharge tube filled with a mixed gas in water and applying a high-voltage negative pulse signal to electrodes in the discharge tube to induce a glow discharge. Smoothness characterized by generating
Method for producing peroxide anion radical. 2. The superoxide anion radical generation according to claim 1, wherein the mixed gas has a mixture ratio of nitrogen and argon of 8: 2, and the pressure of the discharge tube is 4.2 mmHg. Method. 3. The high voltage negative pulse signal has a peak value of 15K.
3. The switch according to claim 2, wherein the frequency is 100 Hz.
Method for producing peroxide anion radical. 4. A high-voltage generating means for generating a high-voltage negative pulse signal, and a discharge tube having electrodes to which the high-voltage negative pulse signal is applied and having a glow discharge unit immersed in water. An apparatus for producing a superoxide anion radical, comprising: 5. The peak value, frequency and duty ratio of the high voltage negative pulse signal are variable, and the peak value of the high voltage negative pulse signal is set to 15 KV and the frequency is set to 100 Hz. 3. The apparatus for producing a superoxide anion radical according to claim 1.