Fluorescence detector for analyzing ultracentrifugation
By introducing an optical system and a vacuum stepper motor system into the fluorescence detector, the problems of unstable optical path and insufficient scanning structure in a vacuum environment are solved, achieving high-precision fluorescence signal acquisition, which is suitable for analyzing ultracentrifugation.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2026-01-16
- Publication Date
- 2026-04-10
AI Technical Summary
Existing fluorescence detectors lack stability in vacuum environments, lack automated high-precision scanning structures, and are structurally unstable, failing to meet the requirements of ultracentrifugation.
A fluorescence detector comprising an optical system and a vacuum stepper motor system was designed. The optical system is fixed on a metal panel, and combined with radial and axial stepper motors, it achieves high-precision scanning, ensuring optical path stability and thermal management.
It achieves high-precision and stable fluorescence signal acquisition in a vacuum environment, has full radial scanning capability, and improves the applicability and accuracy of the detector.
Smart Images
Figure CN121830607A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of analytical ultracentrifugation technology, and in particular to a fluorescence detector for analytical ultracentrifugation. Background Technology
[0002] Analytical ultracentrifugation (AUC) is a crucial method for analyzing the biophysical properties of solutes in solution, widely used in biomedicine, nanomaterials, and other fields, and is considered the "gold standard" for characterization and quality control of gene therapy products. Currently, only Beckman Coulter in the United States provides commercial analytical ultracentrifuges, and there are no commercially available AUC fluorescence detectors. Commercial analytical ultracentrifuges include absorption detectors and interference detectors. To further expand the applicability of AUC, fluorescence detection technology has come into focus for researchers. Compared to other methods, AUC fluorescence detection technology offers advantages in high sensitivity and specificity. Due to the high rotor speed, ultracentrifuges must operate in a vacuum environment; simultaneously, the detector needs to acquire the concentration of the fluorescently labeled substance across the entire radial range (5.8 cm to 7.2 cm) of the sample cell. Therefore, the fluorescence detector needs to operate in a vacuum environment and possess radial scanning capabilities.
[0003] The main problems with existing fluorescence detector structures include: 1) Insufficient vacuum compatibility: Common fluorescence detectors cannot operate stably in a vacuum environment for extended periods, primarily due to the difficulty of heat dissipation for lasers in a vacuum. 2) Lack of automated, high-precision scanning structures: Common fluorescence detectors lack scanning structures. Currently, most fluorescence detectors on the market use sample movement to achieve scanning. 3) Poor structural stability: In fluorescence detectors, the laser and optical components are dispersed, making them susceptible to optical path misalignment due to vibration and installation errors. Summary of the Invention
[0004] This invention aims to at least solve one of the technical problems existing in the prior art. Therefore, addressing the shortcomings of existing fluorescence detection systems in terms of vacuum environment adaptability, optical path stability, and high-precision scanning capability, the purpose of this invention is to provide a fluorescence detector for analyzing ultracentrifugation, achieving high-precision and stable fluorescence signal acquisition.
[0005] To achieve the above-mentioned objectives, the technical solution adopted by the present invention is as follows: a fluorescence detector for analyzing ultracentrifugation, the fluorescence detector comprising an optical system, a metal panel, a first focusing lens and a vacuum stepper motor system; The optical system is mounted on the metal panel and is used to collect the fluorescence signal generated by the sample excited in the ultracentrifuged sample cell via the first focusing lens. The vacuum stepper motor system includes a slide, a radial stepper motor, and an axial stepper motor. The metal panel is mounted on the slide. The radial stepper motor drives the slide to move to achieve radial scanning. The axial stepper motor is connected to the first focusing lens and drives the first focusing lens to move along the axial direction to achieve focusing adjustment.
[0006] In some possible implementations, the optical system includes a laser, a mirror, a beam expander and shaper, a dichroic mirror, a long-pass filter, a second focusing lens, a pinhole, and a photodetector, wherein: The laser emitted by the laser is reflected by the mirror and then expanded and shaped by the beam expander and shaper before being emitted to the dichroic mirror. The light reflected by the dichroic mirror is focused by the first focusing lens into the ultracentrifugal sample cell. The fluorescence signal generated by the laser excitation of the sample in the ultracentrifugal sample cell is collected by the first focusing lens and emitted to the dichroic mirror. The light transmitted by the dichroic mirror is focused by the long-pass filter and the second focusing lens, and the defocused light is filtered out by the pinhole and received by the photodetector and converted into an electrical signal, thereby achieving high-sensitivity detection.
[0007] In some possible implementations, the beam expanding and shaping device employs an aspherical mirror and a collimating lens, wherein the light reflected by the mirror passes sequentially through the aspherical mirror and the collimating lens before being emitted to the dichroic mirror.
[0008] In some possible implementations, the laser wavelength is 488nm, the dichroic mirror cutoff wavelength is 505nm, the focal length of the first focusing lens is 60mm, the long-pass filter cutoff wavelength is 500nm, and the focal length of the second focusing lens is 40mm.
[0009] In some possible implementations, the orifice diameter is 100 μm.
[0010] In some possible implementations, the radial stepper motor is a vacuum-compatible stepper motor, which enables point-to-point scanning of the entire radial region of the ultracentrifuged sample cell under vacuum conditions. The radial stepper motor has a stroke greater than 15 mm and a repeatability accuracy better than 10 μm.
[0011] In some possible implementations, the axial stepper motor is a vacuum-compatible stepper motor, which drives the first focusing lens to make fine adjustments along the optical axis under vacuum conditions, so that the focal point moves between different depths in the ultracentrifuged sample cell. The stroke of the axial stepper motor is greater than 12 mm, and the repeatability is better than 10 μm.
[0012] In some possible implementations, the photodetector employs a photomultiplier tube.
[0013] Because the present invention adopts the above technical solution, it has the following characteristics: 1. High stability in a vacuum environment: Several optical components and lasers of the present invention are uniformly fixed on a metal panel, which has a stable structure and excellent heat dissipation performance, effectively reducing optical path drift and achieving high optical path stability and thermal management.
[0014] 2. High system integration: The overall optical path of this invention is compact and has no external adjustment mechanism, which simplifies structural design and maintenance.
[0015] 3. High-precision scanning capability: This invention uses radial and axial dual stepper motors for control, which are used for radial scanning and axial focusing adjustment respectively, to achieve automatic scanning of the entire radial direction and different depths.
[0016] In summary, this invention, through the design of the optical system, the integrated vacuum design, and the vacuum stepper motor system, can achieve high-precision and stable fluorescence signal acquisition, and can be widely used in fluorescence detection for analysis of ultracentrifugation. Attached Figure Description
[0017] Various other advantages and benefits will become apparent to those skilled in the art upon reading the following detailed description of preferred embodiments. The accompanying drawings are for illustrative purposes only and are not intended to limit the invention. Throughout the drawings, the same reference numerals denote the same parts. In the drawings: Figure 1 This is a diagram of the confocal optical path structure of the fluorescence detector according to an embodiment of the present invention; Figure 2 This is a cross-sectional view of the fluorescence detector structure according to an embodiment of the present invention; Figure 3 This is a partial structural schematic diagram of the fluorescence detector according to an embodiment of the present invention; Figure 4 This is a three-dimensional rendering of the fluorescence detector according to an embodiment of the present invention. Detailed Implementation
[0018] It should be understood that the terminology used herein is for the purpose of describing particular exemplary embodiments only and is not intended to be limiting. Unless the context clearly indicates otherwise, the singular forms “a,” “an,” and “described” as used herein may also include the plural forms. The terms “comprising,” “including,” “containing,” and “having” are inclusive and therefore indicate the presence of the stated features, steps, operations, elements, and / or components, but do not exclude the presence or addition of one or more other features, steps, operations, elements, components, and / or combinations thereof. The method steps, processes, and operations described herein are not construed as requiring them to be performed in a particular order described or illustrated unless the order of performance is explicitly indicated. It should also be understood that additional or alternative steps may be used.
[0019] Although terms such as first, second, third, etc., may be used in this document to describe multiple elements, components, regions, layers, and / or segments, these elements, components, regions, layers, and / or segments should not be limited by these terms. These terms may be used only to distinguish one element, component, region, layer, or segment from another. Unless the context clearly indicates otherwise, terms such as "first," "second," and other numerical terms used herein do not imply order or sequence. Therefore, the first element, component, region, layer, or segment discussed below may be referred to as the second element, component, region, layer, or segment without departing from the teachings of the exemplary embodiments.
[0020] For ease of description, spatial relative terms may be used in the text to describe the relationship of one element or feature relative to another element or feature as shown in the figure. These relative terms include, for example, "inside," "outside," "middle," "outer," "below," "above," etc. Such spatial relative terms are intended to include different orientations of the device in use or operation, other than those depicted in the figure.
[0021] To address the shortcomings of existing fluorescence detector structures, such as insufficient vacuum compatibility, lack of automated high-precision scanning, and poor structural stability, this invention provides a fluorescence detector for analyzing ultracentrifugation. This detector includes an optical system, a metal panel, and a vacuum stepper motor system. The optical system, fixed to the metal panel, collects the fluorescence signal generated by laser excitation of the sample in the ultracentrifuged sample cell via a first focusing lens. The vacuum stepper motor system includes a slide stage, a radial stepper motor, and an axial stepper motor. The metal panel is mounted on the slide stage, and the radial stepper motor moves the slide stage to achieve radial scanning. The axial stepper motor is connected to the first focusing lens, moving the lens up and down axially to achieve focusing adjustment. Therefore, this invention, through the integrated design of the optical system, vacuum system, and vacuum stepper motor system, achieves high-precision and stable fluorescence signal acquisition and can be widely applied to fluorescence detection in ultracentrifugation analysis.
[0022] Exemplary embodiments of the invention will now be described in more detail with reference to the accompanying drawings. While exemplary embodiments of the invention are shown in the drawings, it should be understood that the invention can be implemented in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided to enable a more thorough understanding of the invention and to fully convey the scope of the invention to those skilled in the art.
[0023] like Figures 1-4 As shown, the fluorescence detector for analyzing ultracentrifugation provided in this embodiment includes an optical system and a vacuum stepper motor system.
[0024] The optical system includes a laser 1, a reflector 2, an aspherical mirror 3, a collimating lens 4, a dichroic mirror 5, a focusing lens 6, a long-pass filter 7, a focusing lens 8, a pinhole 9, and a photodetector 10. The laser 1, reflector 2, aspherical mirror 3, collimating lens 4, dichroic mirror 5, focusing lens 6, long-pass filter 7, focusing lens 8, pinhole 9, and photodetector 10 can all be mounted on a large, rigid metal panel 14 using mounting plates. Fixing the laser 1 to the metal panel 14 ensures efficient heat dissipation. The other optical components are mounted on the metal panel 14, thereby maintaining the stability of the optical path structure in a vacuum environment and preventing optical path drift caused by thermal expansion and contraction or mechanical vibration. The laser emitted by laser 1 is reflected by mirror 2, and then expanded and shaped by aspherical mirror 3 and collimating lens 4 before being emitted to dichroic mirror 5. The light reflected by dichroic mirror 5 is focused by focusing lens 6 into the ultracentrifuge sample cell. The fluorescence signal generated by the laser excitation of the sample in the ultracentrifuge sample cell is collected by focusing lens 6 and emitted to dichroic mirror 5. The light transmitted through dichroic mirror 5 is focused after passing through long-pass filter 7 and focusing lens 8, and then filtered out by pinhole 9. The light is received by photodetector 10 and converted into an electrical signal to achieve high-sensitivity detection.
[0025] The vacuum stepper motor system includes a slide 11, a radial stepper motor 12, and an axial stepper motor 13.
[0026] Since the ultracentrifuge sample cell is installed in the rotor of the ultracentrifuge in the application scenario of this invention, in order to obtain radial concentration distribution information, this invention adopts an optical path movement method to achieve radial scanning. Therefore, the metal panel 14 is installed on the slide table 11, and the radial stepper motor 12 drives the slide table 11 to move to achieve radial scanning.
[0027] The axial stepper motor 13 is connected to the focusing lens 6, driving the focusing lens 6 to move up and down along the axial direction to achieve focusing adjustment. Specifically, the axial stepper motor 13 can be connected to the mounting plate that fixes the focusing lens 6.
[0028] In a preferred embodiment of the present invention, the laser wavelength is 488nm, the dichroic mirror cutoff wavelength is 505nm, the focusing lens 4 has a focal length of 60mm, the long-pass filter 5 has a cutoff wavelength of 500nm, and the focusing lens 6 has a focal length of 40mm. This is an example, but not limited to this, and can be selected according to the sample.
[0029] In a preferred embodiment of the present invention, considering both radial resolution and sensitivity, the smaller the aperture diameter, the better the radial resolution, and the larger the aperture diameter, the higher the sensitivity. The choice can be made according to the actual situation. In this embodiment, the aperture diameter is 100 μm.
[0030] In a preferred embodiment of the present invention, the photodetector 10 may be a photomultiplier tube (PMT).
[0031] In a preferred embodiment of the present invention, both the radial stepper motor 12 and the axial stepper motor 13 can be vacuum-compatible stepper motors, enabling automated scanning and focusing adjustment under vacuum conditions, wherein: The radial stepper motor 12 is connected to the slide 11 and is used to drive the entire optical path system to move in the radial direction, so as to realize point-by-point scanning of the entire radial area of the sample cell. The radial stepper motor has a stroke of more than 15 mm and a repeatability positioning accuracy of better than 10 μm.
[0032] The axial stepper motor 13 is connected to the mounting plate of the focusing lens 6 and is used to drive the focusing lens 4 to make fine adjustments along the optical axis, so that the focal point moves between different depths in the sample cell, thereby selecting the most suitable focal depth according to the actual situation of the sample. The stroke of the axial stepper motor 13 is greater than 12mm and the repeatability is better than 10μm.
[0033] The various embodiments in this specification are described in a progressive manner. Similar or identical parts between embodiments can be referred to interchangeably. Each embodiment focuses on describing the differences from other embodiments. In the description of this specification, the terms "a preferred embodiment," "furthermore," "specifically," "in this embodiment," etc., refer to specific features, structures, materials, or characteristics described in connection with that embodiment or example, which are included in at least one embodiment or example of the embodiments in this specification. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described can be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.
[0034] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.
Claims
1. A fluorescence detector for analyzing ultracentrifugation, characterized in that, The fluorescence detector includes an optical system, a metal panel, a first focusing lens, and a vacuum stepper motor system; The optical system is mounted on the metal panel and is used to collect the fluorescence signal generated by the sample in the ultracentrifuged sample cell after excitation via the first focusing lens. The vacuum stepper motor system includes a slide, a radial stepper motor, and an axial stepper motor. The metal panel is mounted on the slide. The radial stepper motor drives the slide to move to achieve radial scanning. The axial stepper motor is connected to the first focusing lens and drives the first focusing lens to move along the axial direction to achieve focusing adjustment.
2. The fluorescence detector for analyzing ultracentrifugation according to claim 1, characterized in that, The optical system includes a laser, a mirror, a beam expander and shaper, a dichroic mirror, a long-pass filter, a second focusing lens, a pinhole, and a photodetector, wherein: The laser emitted by the laser is reflected by the mirror and then expanded and shaped by the beam expander and shaper before being emitted to the dichroic mirror. The light reflected by the dichroic mirror is focused by the first focusing lens into the ultracentrifugal sample cell. The fluorescence signal generated by the laser excitation of the sample in the ultracentrifugal sample cell is collected by the first focusing lens and emitted to the dichroic mirror. The light transmitted by the dichroic mirror is focused after passing through the long-pass filter and the second focusing lens, and then filtered out by the pinhole to remove defocused light before being received by the photodetector, achieving high-sensitivity detection.
3. The fluorescence detector for analyzing ultracentrifugation according to claim 1, characterized in that, The beam expanding and shaping device employs an aspherical mirror and a collimating lens, wherein the light reflected by the mirror passes sequentially through the aspherical mirror and the collimating lens before being emitted to the dichroic mirror.
4. The fluorescence detector for analyzing ultracentrifugation according to claim 1, characterized in that, The laser has a wavelength of 488nm, the dichroic mirror has a cutoff wavelength of 505nm, the first focusing lens has a focal length of 60mm, the long-pass filter has a cutoff wavelength of 500nm, and the second focusing lens has a focal length of 40mm.
5. The fluorescence detector for analyzing ultracentrifugation according to claim 4, characterized in that, The diameter of the aperture is 100 μm.
6. The fluorescence detector for analyzing ultracentrifugation according to claim 1, characterized in that, The radial stepper motor is a vacuum-compatible stepper motor, which enables point-to-point scanning of the entire radial region of the ultracentrifuged sample cell under vacuum conditions. The radial stepper motor has a stroke greater than 15 mm and a repeatability accuracy better than 10 μm.
7. The fluorescence detector for analyzing ultracentrifugation according to claim 1, characterized in that, The axial stepper motor is a vacuum-compatible stepper motor. Under vacuum conditions, it drives the first focusing lens to make fine adjustments along the optical axis, so that the focal point moves between different depths in the ultracentrifuged sample cell. The stroke of the axial stepper motor is greater than 12 mm, and the repeatability is better than 10 μm.
8. The fluorescence detector for analyzing ultracentrifugation according to claim 2, characterized in that, The photodetector is a photomultiplier tube.