Dual-purpose detector for simultaneously measuring fluorescence and ultraviolet visible absorption

Abstract

The invention discloses a dual-purpose detector for simultaneously measuring fluorescence and ultraviolet visible absorption, which comprises a light path system, and a light source, a flow cell, a fluorescence detector and an ultraviolet detector which are arranged in the light path system, the fluorescence detector is arranged in the vertical direction of the flow cell, and the ultraviolet detector is arranged in the horizontal direction of the flow cell; a light beam emitted by the light source enters a detection area of the flow cell from the horizontal direction of the flow cell, interacts with a sample flowing in the flow cell, and then is emitted from the horizontal direction of the flow cell, and the light intensity of the light beam emitted from the horizontal direction of the flow cell is detected by the ultraviolet detector; when the sample has fluorescence characteristics, the light beam emitted by the light source interacts with the sample in the flow cell to excite fluorescence, and the fluorescence is detected by the fluorescence detector in the vertical direction. According to the invention, ultraviolet absorption detection and fluorescence detection of a sample can be simultaneously realized on one instrument, and information of the sample in multiple aspects can be obtained.

Description

Technical Field

[0001] The invention relates to a liquid chromatography detector, in particular to a dual-purpose detector for simultaneously measuring fluorescence and ultraviolet-visible absorption. Background Art

[0002] There are many types of detectors in the liquid phase system, among which the optical detector is the most common and universal detector. Its principle is based on the characteristics of the absorption of light by the substance, and is used to achieve quantitative or qualitative detection of the sample. Among them, the UV-visible light detector allows the light in the ultraviolet and visible bands to pass through the sample area. The intensity and wavelength components of the emitted light are compared with the intensity and wavelength components of the incident light to obtain the optical characteristics of the substance. According to the Ludwig-Beer law, the composition, relative content and other characteristics of the sample substance can be obtained. The fluorescence detector uses excitation light to illuminate the sample in the flow cell, causing the sample with fluorescence characteristics to emit fluorescence, and the substance is quantitatively or qualitatively determined by detecting the fluorescence signal.

[0003] In chemical analysis laboratories, multiple samples need to be tested on a daily basis. For different samples based on UV detection or fluorescence methods, more than two detectors are usually required. If the liquid circuits of two detectors are connected in series, there is a risk that the sample will diffuse in the liquid circuit, resulting in a reduced signal. Or if the liquid circuit connection method is changed, the newly set liquid circuit needs to be flushed and the liquid circuit system needs to be balanced. Not to mention the problem of increased sample testing costs due to purchasing instruments, maintaining and replacing consumables. Summary of the invention

[0004] In order to solve the above-mentioned deficiencies in the prior art, the purpose of the present invention is to provide a dual-purpose detector for simultaneously measuring fluorescence and ultraviolet-visible absorption. The present invention can simultaneously realize ultraviolet absorption detection and fluorescence detection of samples on one instrument to obtain various information of the samples.

[0005] The technical solution adopted by the present invention to solve the technical problem is: a dual-purpose detector for simultaneously measuring fluorescence and ultraviolet-visible absorption, comprising an optical path system and a light source, a flow cell, a fluorescence detector and an ultraviolet detector arranged in the optical path system, wherein the fluorescence detector is arranged in the vertical direction of the flow cell, and the ultraviolet detector is arranged in the horizontal direction of the flow cell;

[0006] The light beam emitted by the light source enters the detection area of ​​the flow cell from the horizontal direction of the flow cell, and after interacting with the sample flowing in the flow cell, it is emitted from the horizontal direction of the flow cell, and the light intensity of the light beam emitted from the horizontal direction of the flow cell is detected by the ultraviolet detector;

[0007] When the sample has fluorescence characteristics, the light beam emitted by the light source interacts with the sample in the circulation pool to excite fluorescence, and the fluorescence is detected in a vertical direction by the fluorescence detector.

[0008] Optionally, a first monochromator is provided in the front light path of the circulation cell, and a second monochromator is provided in the front light path of the fluorescence detector.

[0009] Optionally, a proportional beam splitter is further provided in the optical path between the first monochromator and the circulation cell. The monochromatic light formed by the light source after passing through the monochromator forms two beams of light after passing through the proportional beam splitter, one of which is directed to the circulation cell to form a detection beam, and the other is directed to the preceding detector to form a reference beam.

[0010] Optionally, the circulation pool is provided with a reflector on the side opposite to the fluorescence detector, and a first convex lens and a second convex lens are respectively provided at both ends of the circulation pool in the horizontal direction, and the circulation pool is provided with a third convex lens on the side opposite to the reflector.

[0011] Optionally, the front-stage detector is a photodiode.

[0012] By adopting the above technical scheme, the present invention can simultaneously detect the absorption characteristics and emission characteristics of the sample material, thereby obtaining detailed and comprehensive data information of the sample material, and realizing accurate characterization and precise quantification of the sample through a variety of analytical methods. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 It is a schematic diagram of the system structure of the present invention. DETAILED DESCRIPTION

[0014] The present application is further described in detail below in conjunction with the accompanying drawings and embodiments. It is to be understood that the specific embodiments described herein are only used to explain the relevant invention, rather than to limit the invention. It is also necessary to explain that, for ease of description, only the parts related to the invention are shown in the accompanying drawings.

[0015] It should be noted that, in the absence of conflict, the embodiments and features in the embodiments of the present application can be combined with each other. The present application will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0016] like Figure 1 As shown, the present invention discloses a dual-purpose detector for simultaneously measuring fluorescence and ultraviolet-visible absorption. The detector is mainly used for qualitative or quantitative analysis of substances in multi-component samples in liquid chromatography. The detector includes an optical path system and a light source 100, a circulation cell 200, a fluorescence detector 300 and an ultraviolet detector 400 arranged in the optical path system, wherein the fluorescence detector 300 is arranged in the vertical direction of the circulation cell 200, and the ultraviolet detector 400 is arranged in the horizontal direction of the circulation cell 200.

[0017] In the present invention, the circulation cell 200 has light transmittance in two directions, namely, light transmittance in the horizontal direction and light transmittance in the vertical direction. Usually, the interior of the circulation cell 200 has a Z-shaped circulation channel, and the middle part of the circulation channel is the detection area of ​​the circulation cell 200. During detection, the light beam emitted by the light source 100 is injected into the detection area of ​​the circulation cell 200 from the horizontal direction of the circulation cell 200, and after interacting with the sample flowing in the circulation cell, it is emitted from the horizontal direction of the circulation cell 200, and the light intensity of the light beam emitted from the horizontal direction of the circulation cell is detected by the ultraviolet detector 400. In addition, when the sample has fluorescence characteristics, the light beam emitted by the light source 100 will also interact with the sample in the circulation cell to excite fluorescence, and the fluorescence is detected by the fluorescence detector 300 in the vertical direction.

[0018] In the present invention, a first monochromator 500 is provided in the front optical path of the circulation cell 200, and the wavelength of the light beam incident into the circulation cell 200 can be selectively adjusted through the first monochromator 500. A proportional beam splitter 600 is also provided in the optical path between the first monochromator 500 and the circulation cell 200. The monochromatic light formed by the light source 100 after passing through the first monochromator 500 forms two beams of light after passing through the proportional beam splitter 600, one of which is directed to the circulation cell 200 to form a detection beam, and the other is directed to the front detector 700 to form a reference beam. The front detector 700 can use a photodiode to provide a reference signal of the initial light intensity. After the ultraviolet detector 400 detects the light intensity signal, it is compared with the reference signal to obtain the absorbance information of the sample. In addition, the proportional beam splitter 600 can be implemented using a beam splitter with a dielectric film coating, or a beam splitter partially coated with a reflective film.

[0019] In the present invention, a second monochromator 800 is further provided in the front optical path of the fluorescence detector 300. The second monochromator 800 can separate the fluorescence signal by wavelength and scan the fluorescence spectrum to obtain fluorescence spectrum information. Since the fluorescence signal is relatively weak, a photomultiplier tube can be used as the detection element of the fluorescence detector 300.

[0020] In the present invention, a reflector 900 is provided on the opposite side of the fluorescence detector 300 of the circulation pool 200, and a first convex lens 210 and a second convex lens 220 are provided at both ends of the circulation pool 200 in the horizontal direction. A third convex lens 230 is provided on the opposite side of the circulation pool 200 from the reflector 900. By setting the convex lens, the light beam can be converged to improve the responsiveness of the light beam signal.

[0021] The above description is only a preferred embodiment of the present application and an explanation of the technical principles used. Those skilled in the art should understand that the scope of the invention involved in the present application is not limited to the technical solution formed by a specific combination of the above technical features, but should also cover other technical solutions formed by any combination of the above technical features or their equivalent features without departing from the inventive concept. For example, the above features are replaced with (but not limited to) technical features with similar functions disclosed in the present application.

[0022] Except for the technical features described in the specification, the remaining technical features are known technologies to those skilled in the art. In order to highlight the innovative features of the present invention, the remaining technical features will not be described here in detail.

Claims

1. A dual-purpose detector for simultaneously measuring fluorescence and ultraviolet-visible absorption, characterized in that: It comprises an optical path system and a light source, a circulation cell, a fluorescence detector and an ultraviolet detector arranged in the optical path system, wherein the fluorescence detector is arranged in the vertical direction of the circulation cell, and the ultraviolet detector is arranged in the horizontal direction of the circulation cell; The light beam emitted by the light source enters the detection area of ​​the flow cell from the horizontal direction of the flow cell, and after interacting with the sample flowing in the flow cell, it is emitted from the horizontal direction of the flow cell, and the light intensity of the light beam emitted from the horizontal direction of the flow cell is detected by the ultraviolet detector; When the sample has fluorescence characteristics, the light beam emitted by the light source interacts with the sample in the circulation pool to excite fluorescence, and the fluorescence is detected in a vertical direction by the fluorescence detector.

2. The dual-purpose detector for simultaneously measuring fluorescence and ultraviolet-visible absorption according to claim 1, characterized in that: A first monochromator is provided in the front light path of the circulation cell, and a second monochromator is provided in the front light path of the fluorescence detector.

3. The dual-purpose detector for simultaneously measuring fluorescence and ultraviolet-visible absorption according to claim 2, characterized in that: A proportional beam splitter is also provided in the optical path between the first monochromator and the circulation pool. The monochromatic light formed by the light source after passing through the first monochromator forms two beams of light after passing through the proportional beam splitter, one of which is directed to the circulation pool to form a detection beam, and the other is directed to the preceding detector to form a reference beam.

4. The dual-purpose detector for simultaneously measuring fluorescence and ultraviolet-visible absorption according to claim 3, characterized in that: The circulation pool is provided with a reflector on the side opposite to the fluorescence detector, and a first convex lens and a second convex lens are respectively provided at both ends of the circulation pool in the horizontal direction. The circulation pool is provided with a third convex lens on the side opposite to the reflector.

5. The dual-purpose detector for simultaneously measuring fluorescence and ultraviolet-visible absorption according to claim 4, characterized in that: The front-stage detector is a photodiode.

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