JPH0536741B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an electrophoresis device. More particularly, the present invention relates to an electrophoresis device that uses laser light as a detection means and is provided with a safety mechanism to protect the operator and the optical system.

[Prior Art] Gel electrophoresis is widely used as a method for determining base sequences of DNA and the like.

Conventionally, samples were labeled with radioisotopes and analyzed during electrophoresis, but this method had the disadvantage of being laborious and time-consuming. For this reason,
Recently, methods of labeling samples with fluorescent substances are being considered.

In the method using light, fluorescently labeled DNA fragments are run in a gel, but from the start of the run, 15
A photoexcitation section and a photodetector are provided for each migration path ~20 cm below, and the DNA fragments passing through these sections are sequentially measured. From the detection time to the migration speed, i.e.
You can see the size of DNA fragments.

JP-A No. 63-21556 discloses that the line on the gel of an electrophoresis device irradiated with a laser and the array direction of the photodiode array are configured to be perpendicular to the direction of migration of DNA fragments in the electrophoresis device. Ta
A DNA base sequencing device is disclosed.

FIG. 6 is a schematic diagram illustrating the configuration of the device.

As shown in the figure, the laser light emitted from the light source 70 is bent by a mirror 72 and irradiates the migration plate 74 from the side. Fluorescent label DNA7 in the irradiation area
When 6 is reached, it emits fluorescence. Fluorescent light from each migration path is imaged by a lens 78 on a light receiving section 82 of an image intensifier 80. This signal is amplified, converted into an electrical signal by a photodiode array 84, and measured.

[Problems to be Solved by the Invention] When performing electrophoresis, an electrophoresis plate is set in a measurement chamber during analysis, and after the analysis is completed, it is removed from the measurement chamber and a new electrophoresis plate is set in the measurement chamber again.

However, since such devices use components that are dangerous to the human body, such as laser beams and high-voltage power supplies, a mechanism to protect the operator is required.

Furthermore, if the door of the measurement chamber is opened by mistake during measurement, a large amount of strong external light may enter the fluorescence detection optical system, potentially destroying the optical detection system.

Conventional optical detection type electrophoresis devices that use laser light have not been provided with a safety mechanism to protect the operator and the optical system.

SUMMARY OF THE INVENTION Accordingly, it is an object of the present invention to provide an optical detection electrophoresis device using laser light that has a safety mechanism to protect the operator and the optical system.

[Means for Solving the Problems] In order to achieve the above object, in the electrophoresis apparatus of the present invention, a means for detecting the setting of the electrophoresis plate is provided in the holder for vertically holding the electrophoresis plate, and,
A door that can be opened and closed to make the measurement chamber hermetically sealed is equipped with a means to detect the opening and closing of the door, and if the correct setting of the electrophoresis plate and the securely closed state of the door are not detected, the shutter of the laser light source is opened. If the door is accidentally opened during measurement, at least the shutter of the optical detection system will be opened based on the signal from the detection means installed on the door. configured to be closed.

Preferably, a proximity switch is used as the detection means.

Preferably, the optical detection system has an image intensifier.

The laser oscillator preferably has a shutter.

[Function] As described above, the electrophoresis apparatus of the present invention is provided with a double safety mechanism so that laser light irradiation is not started unless the electrophoresis plate is set and the door is closed. Therefore, it is extremely safe for the operator.

Additionally, even if the door is accidentally opened during measurement, at least the shutter of the optical detection system is closed at the same time, so the image intensifier used in the optical detection system will not be damaged by external light. .

[Example] Hereinafter, the electrophoresis apparatus of the present invention will be described in more detail with reference to the drawings.

FIG. 1 is a perspective view showing the appearance of the electrophoresis device of the present invention, FIG. 2 is an optical path diagram showing the movement of laser light in the electrophoresis device of the present invention, and FIG. 4 is a block diagram showing the operation of the safety mechanism in the device, FIGS. 4a and 4b are schematic diagrams showing an example of the arrangement of means for detecting the opening and closing of the door, and FIG. FIG. 3 is a schematic diagram illustrating an example of the arrangement of means for detecting that the setting of

As shown in FIG. 1, the electrophoresis apparatus 1 of the present invention has a darkroom 3. A door 5 that can be opened and closed is provided in front of the darkroom 3, and the darkroom 3 is closed during measurement.
can be sealed.

The electrophoresis plate 7 is held vertically by a electrophoresis plate holder 9 in a dark room. Buffer tanks 11 and 13 are provided at the upper and lower parts of the holder 9 to store buffer solutions necessary for gel electrophoresis. The upper and lower ends of the electrophoresis plate are immersed in a buffer solution in each buffer tank. In order to conduct electricity from the upper buffer solution to the lower buffer solution through the gel electrolyte layer between the electrophoresis plate, an electrode 15 is provided in each of the upper buffer tank and the lower buffer tank.
and 17 are provided. The electrophoresis plate 7 can be attached to and detached from the holder 9 by the clamp mechanism 19. A laser beam irradiation end 21 is provided on a side wall at a position perpendicular to the electrophoresis plate 7 . The laser beam irradiation end 21 is arranged so that the optical axis of the laser beam irradiation end coincides with the gel electrolyte layer of the migration plate. In order to maintain the temperature in the dark room constant, an air outlet or air blowing fan 23 is provided directly above the laser beam irradiation end 21. An outlet 25 of the exhaust duct is provided on the opposite side wall facing the air outlet.

The optical system in the electrophoresis apparatus of the present invention has a laser light source consisting of a laser oscillator 27, as shown in FIG. It is preferable to provide the shutter 29 adjacent to the laser beam exit of the laser oscillator. Expanded lens 3 on the optical axis of the laser beam
1, and mirrors 33 and 35 refract the laser beam at right angles to the original optical axis. The refracted laser light is introduced into the dark room from the laser light irradiation end 21 and is irradiated onto the gel electrolyte layer between the two electrophoresis plates. As the laser light passes through the gel electrolyte layer, it hits the analyte sample labeled with the fluorescent substance, which emits fluorescence. This fluorescence is caused by the condensing hood 37
The light is focused and incident on the fluorescence detector 39.
A shutter 41 is disposed between the condensing hood 37 and the detector 39. An image intensifier or the like is used as a fluorescence detector.

As shown in FIG. 3, the migration plate set presence/absence detection means 43 and the door opening/closing detection means 45 are connected to a control circuit 47. Inside the control circuit 47, there is provided an AND logic circuit 49 which receives detection signals from the respective detection means, and drives the laser oscillator side shutter 29 and the fluorescence detector side shutter 41 based on the AND condition. Even if the door is closed, each shutter will not open unless the migration plate is set. Further, even if each shutter is opened, if the door is opened during measurement, the AND condition will not be satisfied, so the fluorescence detector side shutter 41 and the laser oscillator side shutter 29 are closed at the same time. In this way, the safety of the operator is sufficiently ensured, and the fluorescence detector, such as the image intensifier, is reliably protected from destruction by extraneous light.

The electrophoretic plate set detection means and the door opening/closing detection means used in the present invention are not particularly limited, and all known detection means can be used. It is preferable to use a proximity switch in terms of detection reliability and quick response. A proximity switch is a sensor that detects the eddy current generated when a conductor such as a piece of iron enters a coil.

The method of attaching the proximity switch is also not particularly limited.
For example, as shown in FIG. 4a, a bearing 51 is provided on the outside of the back wall of the darkroom, and a proximity switch 53 is attached to this bearing. On the other hand, a detection plate such as an iron piece 59 is disposed on a slide block 57 that slides on the shaft 55. As shown in FIG. 4b, a door fixing bracket 61 is provided on the slide block 57, and the door 5 is attached thereto.

In the case of a migration plate holder, for example, as shown in FIG.
A proximity switch 53 is provided. When the knob of the clamp mechanism is rotated, the detection plate also rotates, approaches the proximity switch, and detects the setting of the migration plate 7.
Of course, arrangement methods other than those illustrated can also be implemented. Such an arrangement method can be easily conceived by those skilled in the art.

[Effects of the Invention] As explained above, the electrophoresis apparatus of the present invention is provided with a double safety mechanism so that laser light irradiation is not started unless the electrophoresis plate is set and the door is closed. Therefore, it is extremely safe for the operator.

Additionally, even if the door is accidentally opened during measurement, at least the shutter of the optical detection system is closed at the same time, so the image intensifier used in the optical detection system will not be damaged by external light. .

[Brief explanation of the drawing]

FIG. 1 is a perspective view showing the appearance of the electrophoresis device of the present invention, FIG. 2 is an optical path diagram showing the movement of laser light in the electrophoresis device of the present invention, and FIG. FIG. 4 is a block diagram showing the operation of the safety mechanism in the device, FIG. Fig. 5 is a partial schematic plan view showing an example of the arrangement of means for detecting that the electrophoresis plate is set in the electrophoresis plate holder, and Fig. 6 is a DNA base sequence determination device disclosed in Japanese Patent Application Laid-Open No. 63-21556. FIG. 1... Electrophoresis device, 3... Dark room, 5... Door, 7... Electrophoresis plate, 53... Proximity switch, 59... Detection plate.

Claims (1)

[Claims] 1. In a gel electrophoresis device that uses laser light as a detection means, a holder for vertically holding the migration plate is provided with a migration plate set detection means for detecting the setting of the migration plate, and the measurement chamber can be sealed. The openable/closeable door is provided with a door opening/closing detection means for detecting the opening/closing of the outer door, and further includes a shutter opening/closing mechanism including a laser light source and an optical detection system, and the shutter opening/closing mechanism is configured to detect the movement plate set detection means. A first detection signal indicating the presence or absence of the electrophoresis plate set, and a second detection signal indicating the open/closed state of the door from the door open/close detection means.
In response to the detection signal, when the first detection signal indicates the electrophoresis plate set state and the second detection signal indicates the door open/closed state, the shutter of the laser light source and the shutter of the optical detection system are activated. An electrophoresis apparatus characterized in that at least a shutter of an optical detection system is closed when the second detection signal indicates a door open state during gel electrophoresis measurement.