JPH0833344B2 - Densitometer - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial field of application) The present invention is used for quantitative measurement of thin layer plates (TLC) and electrophoretic gels, and irradiates a sample plate with light from a light source through a spectroscope to obtain a sample. The present invention relates to a densitometer for quantitatively measuring substances separated on a plate.

(Prior Art) Densitometers include a system in which a continuous light source having a continuous wavelength is used as a light source and a sample is irradiated with light by a spectroscope, and a system in which a laser is used as a light source.

A system using a decomposer and a continuous light source can (1) use any wavelength as measurement light and can be used in any case. (2) pretreatment of coloring with a coloring reagent can be omitted.
Although it has such advantages, (1) it is difficult to obtain a light source with high energy, (2) normal spectroscope has stray light, and there is no linearity in the photometric value when the absorbance is 3.0 or more. It has disadvantages.

On the other hand, a densitometer using a laser as a light source (1) can obtain light with high energy, and (2) can obtain light with high monochromaticity.
On the other hand, it has the advantage that it can measure 0 or more. (1) The sample must be colored by pretreatment so that it absorbs light of a specific wavelength. (2) Sample irradiation light of any shape. It is difficult to do so.

Thus, it can be said that a densitometer using a spectroscope has a character as a general-purpose machine, whereas a densitometer using a laser light source has a character as a dedicated machine for a specific substance.

Conventionally, a densitometer using a continuous light source and a spectroscope,
The densitometer using a laser exists independently of each other.

(Problems to be solved by the invention) Depending on the sample plate, it may be more convenient to use a densitometer using a continuous light source and a spectroscope, and conversely, it may be more convenient to use a densitometer using a laser. is there. However, conventionally, since there is no densitometer having both the characteristics of a general-purpose machine and the characteristics of a dedicated machine, it is necessary to prepare two types of devices.

The present invention, with one densitometer, is intended to achieve both the characteristics as a wavelength tunable general-purpose machine using a continuous light source and a spectroscope, and the characteristics as a dedicated machine using a laser light source. is there.

(Means for Solving Problems) In the densitometer of the present invention, the light source chamber is provided with a continuous light source and a laser, and the light source chamber is further provided with a spherical mirror for continuous light source selection and a plane mirror for laser selection so as to be switchable. In the spectroscope, a spectroscopic element is detachably attached to the optical path, and the exit slit of the spectroscope is variable so that it can be widened sufficiently wider than the laser beam.

(Embodiment) The figure shows an optical system according to an embodiment of the present invention.

A light source chamber 2 is provided with a continuous light source 4 such as a tungsten lamp or a deuterium lamp and a laser 6.
A light source switching mechanism 8 is also provided in the light source chamber 2, and a spherical mirror 10 and a plane mirror 12 are mounted on the light source switching mechanism 8. The light source switching mechanism 8 rotates to rotate the spherical mirror 10 or the plane mirror.
Move 12 to the light source selection position. When the continuous light source 4 is used, the light from the continuous light source 4 is focused on the entrance slit 16 of the spectroscope 14 by the spherical mirror 10, and when the laser 6 is used, the laser light is reflected by the plane mirror 12 as shown in the figure. Entrance slit
Inject into 16.

In the spectroscope 14, the diffraction grating 18 and the plane mirror 20 can be switched by a switching mechanism 22. The light that has entered from the entrance slit 16 enters the diffraction grating 18 or the plane mirror 20 through the condenser mirror 24, and exits from the exit slit 26.
When the continuous light source 4 is used, the diffraction grating 18 is used to configure the spectroscope, while when the laser 6 is used, the plane mirror 20 is used to use all energy. Laser light has a high degree of parallelism, but in reality it has a slight spread of the beam, so it becomes a large light beam if it passes through a long optical path. Therefore, the entrance slit is made by the condenser mirror 24 of the spectroscope 14.
The image at the position of 16 is formed on the exit slit 26.

The width of the exit slit 26 is variable, and when using laser light, the entire energy of the laser light is used by expanding the width sufficiently wider than the light flux.

A condenser mirror 28 forms an image of the exit slit 26 of the spectroscope on the sample plate 30. Exit slit 26 and condensing mirror 28
A half mirror 32 is provided between them. A part of the light exiting the exit slit 26 is monitored by the half mirror 32.
It is incident on 34 and is used as a signal to correct temporal energy fluctuations.

The light incident on the sample plate 30 is detected by the reflected light detector 36 or the transmitted light detector 38 depending on the measurement mode.

The above embodiment shows an example in which a diffraction grating is used for the spectroscope, but it can also be applied to the case of a filter spectroscopy method that does not use a diffraction grating. In that case, when using a continuous light source, install the filter at a predetermined position so that the measurement light passes through the filter with a spectroscope, and when using a laser, set the filter at the predetermined position so that the measurement light does not pass through the filter. Should be removed from.

According to the present invention, a continuous light source and a laser are provided in a light source chamber so that both light sources can be switched and used. When the continuous light source is used, a spectroscopic element is used in a spectroscope, and a laser is used. In case of using, the total energy is used in the spectroscope without using the spectroscopic element, and the exit slit of the spectroscope is widened sufficiently wider than the laser beam. As a result, a versatile spectroscopic method using a continuous light source,
Dedicatedness using a laser light source can be realized at the same time. The same photometric method and data processing as those of the conventional general-purpose machine can be used.

[Brief description of drawings]

 FIG. 1 is a schematic diagram showing an optical system according to an embodiment of the present invention. 2 ... Light source room, 4 ... Continuous light source, 6 ... Laser, 8 ... Switching mechanism, 10 ... Spherical mirror, 12 ... Plane mirror, 14 ... Spectroscope, 18 ... Diffraction grating, 20 ... Plane mirror, 22 …… Switching mechanism, 26 …… Exit slit.

Claims (1)

[Claims] 1. A densitometer for quantitatively measuring a substance separated on a sample plate by irradiating a sample plate with light from a light source in the light source chamber, the continuous light source and a laser being provided in the light source chamber. In the light source chamber, a spherical mirror for continuous light source selection and a plane mirror for laser selection are switchably provided, a spectroscopic element is detachably provided in an optical path in the spectroscope, and an exit slit of the spectroscope is provided with a laser beam. A variable densitometer that can be expanded to a sufficiently wider width.