Single molecule dynamic tracking method and system based on laser positioning

Abstract

The present application relates to the technical field of molecular tracking, and particularly relates to a single-molecule dynamic tracking method and system based on laser positioning. The method comprises: emitting three laser points vertically projected on a sample table on the sample table with a molecule to be measured; adjusting the positions of the three laser points so that the three laser points and the molecule to be measured form a preset planar geometric relationship multiple times in the dynamic change process of the molecule to be measured; the preset planar geometric relationship is defined as that the distance length of the connecting line between the three laser points vertically projected on the sample table forms a right triangle, and the molecule to be measured is located at the midpoint of the hypotenuse of the right triangle; at each time when the preset planar geometric relationship is formed, the coordinates of the three laser points at this time are obtained, and the coordinates of the molecule to be measured are calculated by using the preset planar geometric relationship, so as to obtain multiple coordinates of the molecule to be measured in the dynamic change process of the molecule to be measured when the preset planar geometric relationship is formed multiple times, thereby being suitable for devices with limited computing power.

Description

Technical Field

[0001] This invention relates to the field of molecular tracking technology, and in particular to a single-molecule dynamic tracking method and system based on laser positioning. Background Technology

[0002] In fields such as biomedicine, chemical analysis, and materials science, dynamically tracking the position of molecules is crucial for understanding molecular behavior, reaction mechanisms, and material properties. However, most existing algorithms for dynamically tracking molecular positions rely on complex probability distribution calculations. These algorithms are computationally intensive, demanding high computational resources, and are not suitable for resource-constrained microcontroller systems. Summary of the Invention

[0003] To address the shortcomings of existing methods for dynamically tracking molecular positions, this invention provides a method and system for single-molecule tracking based on laser positioning, the specific solution of which is as follows: In a first aspect, the present invention provides a single-molecule dynamic tracking method based on laser positioning, comprising the following steps: Three laser points are emitted vertically onto a sample stage containing the molecule to be tested; The positions of the three laser points are adjusted so that the three laser points and the molecule to be tested form a preset planar geometric relationship multiple times during the dynamic change of the molecule to be tested; the preset planar geometric relationship is defined as the distance between the lines connecting the three laser points that are perpendicularly projected onto the sample stage forming a right triangle, and the molecule to be tested is located at the midpoint of the hypotenuse of the right triangle; Each time the preset planar geometric relationship is formed, the coordinates of the three laser points are obtained, and the coordinates of the molecule under test are calculated using the preset planar geometric relationship, thereby obtaining multiple coordinates of the molecule under test during the dynamic change process when the preset planar geometric relationship is formed multiple times.

[0004] In one embodiment, the method further includes the step of: plotting the motion trajectory curve of the dynamic change of the molecule under test based on multiple coordinates obtained during the dynamic change process of the molecule under test.

[0005] In one embodiment, by acquiring the fluorescence of the molecule to be tested, the distances between the three laser points and the molecule to be tested are obtained by using a photon counter to collect the distances between each laser point and the fluorescence.

[0006] In one embodiment, adjusting the positions of the three laser points so that the three laser points and the molecule to be tested repeatedly form a preset planar geometric relationship during the dynamic changes of the molecule to be tested includes the following steps: Obtain the distances between the three laser points and the molecule to be tested; Compare the pairwise distances between the three laser points and the molecule to be tested; The coordinate values ​​of the three laser points are corrected by comparing the differences between the pairwise distances between the three laser points and the molecule to be tested, and by combining the preset planar geometric relationship. Adjust the positions of the three laser points according to the corrected coordinate values ​​until the three laser points and the molecule to be tested form the preset planar geometric relationship.

[0007] In one embodiment, the positions of the three laser points are defined as A, B, and C, the position of the molecule to be tested is N, and the distances between the three laser points and the molecule to be tested are denoted as L. NA L NB L NC When the distance between the three laser points forms a right triangle, laser point B is taken as the right-angle vertex of the right triangle, and the extension of BA is taken as the Y-coordinate direction and the extension of BC is taken as the X-coordinate direction to obtain a plane rectangular coordinate system. The formula for comparing the pairwise distances between the three laser points and the molecule to be tested, and correcting the coordinate values ​​of the three laser points by combining the differences between the pairwise distances between the three laser points and the molecule to be tested with the preset planar geometric relationship, is as follows: If L NA >L NB Then, the Y coordinate values ​​of the current three laser points A, B, and C are each reduced by (L). NA -L NB )*β, to obtain the corrected Y coordinate values ​​of the three laser points A, B, and C; If L NA <L NB Then, the Y coordinate values ​​of the three current laser points A, B, and C are each increased by (L... NB -L NA )*β, to obtain the corrected Y coordinate values ​​of the three laser points A, B, and C; If L NC >L NB Then, the X coordinate values ​​of the current three laser points A, B, and C are each reduced by (L). NC -L NB )*β, to obtain the corrected X coordinate values ​​of the three laser points A, B, and C; If L NC <L NB Then, the X coordinate values ​​of the three current laser points A, B, and C are each increased by (L). NB -LNC )*β, to obtain the corrected X coordinate values ​​of the three laser points A, B, and C; If L NA =L NB =L NC This indicates that the correction is complete; In the formula, β represents the adjustment coefficient, which is obtained based on factors such as laser intensity, laser irradiation time, and molecular motion speed.

[0008] In one embodiment, in the preset planar geometric relationship, the right triangle formed by the distance between the lines connecting the three laser points is an isosceles right triangle.

[0009] Secondly, the present invention also provides a single-molecule dynamic tracking system based on laser positioning, comprising: The sample stage is used to place the molecules to be tested. A laser emitting module is used to emit three laser points that are vertically projected onto the sample stage; An adjustment module is used to adjust the positions of the three laser points so that the three laser points and the molecule to be tested form a preset planar geometric relationship multiple times during the dynamic changes of the molecule to be tested; the preset planar geometric relationship is defined as the distance between the lines connecting the three laser points that are perpendicularly projected onto the sample stage forming a right triangle, and the molecule to be tested is located at the midpoint of the hypotenuse of the right triangle; The calculation module is used to obtain the coordinates of the three laser points each time the preset planar geometric relationship is formed, and to calculate the coordinates of the molecule to be tested using the preset planar geometric relationship.

[0010] In one embodiment, a plotting module is further included, which is used to plot the motion trajectory curve of the dynamic change of the molecule under test based on multiple coordinates obtained during the dynamic change process of the molecule under test.

[0011] In one embodiment, a control module is also included, which is electrically connected to the laser emission module, the adjustment module, and the calculation module, respectively.

[0012] In one embodiment, a communication module is also included, which is used to transmit the coordinate data of the molecule to be tested calculated in the calculation module to a host computer.

[0013] Based on the above, compared with the prior art, the laser-based single-molecule tracking method provided by the present invention can quickly determine the position of molecules by forming a preset planar geometric relationship through laser positioning and simple calculation, avoiding complex probability distribution calculations, significantly reducing computational complexity and improving tracking efficiency.

[0014] Other features and beneficial effects of the invention will be set forth in the following description, and will be apparent in part from the description, or may be learned by practicing the invention. The objects of the invention and other beneficial effects can be realized and obtained by means of the structures particularly pointed out in the description, claims and drawings. Attached Figure Description

[0015] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort. Unless otherwise specified, the positional relationships shown in the drawings in the following description are based on the direction in which the components are drawn in the figure.

[0016] Figure 1 A flowchart illustrating the steps of a laser-based single-molecule dynamic tracking method according to an embodiment of the present invention; Figure 2 This is a flowchart illustrating the specific steps of step S20 in one embodiment of the present invention; Figure 3 This is a schematic diagram of the preset planar geometric relationship formed by three laser points A, B, and C and the molecule to be tested N in one embodiment of the present invention. Detailed Implementation

[0017] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. The technical features designed in the different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0018] In the description of this invention, it should be noted that all terms used in this invention (including technical and scientific terms) have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains, and should not be construed as limiting the invention; it should be further understood that the terms used in this invention should be understood to have the same meaning as those in the context of this specification and in the relevant field, and should not be understood in an idealized or overly formal sense, except as expressly defined in this invention.

[0019] To address the problem that most existing algorithms for dynamically tracking molecular positions rely on complex probability distribution calculations, leading to insufficient computing power or resources, this invention provides a method and system for single-molecule tracking based on laser positioning. This method utilizes laser positioning and simple calculations to dynamically track the position of molecules, thereby effectively reducing computational and device complexity.

[0020] The technical solution of the present invention will be described and explained in detail below with reference to different embodiments and accompanying drawings through various specific implementation methods.

[0021] Example 1 Please see Figure 1 This embodiment provides a single-molecule dynamic tracking method based on laser positioning, including the following steps: Step S10: Three laser points are emitted onto the sample stage containing the molecule to be tested, with vertical projections onto the sample stage. In this embodiment, the emission of the laser points can be achieved using a laser emitting device. The emission intensity and irradiation time of the three laser points are the same to facilitate subsequent calculations.

[0022] Preferably, in the initial state, the three laser points form a right triangle; more preferably, in the initial state, the three laser points and the molecule to be tested form a preset planar geometric relationship, so as to facilitate subsequent fine-tuning of the positions of the three laser points according to the dynamic changes of the molecule.

[0023] Step S20: Adjust the positions of the three laser points so that the three laser points and the molecule to be tested form a preset planar geometric relationship multiple times during the dynamic changes of the molecule to be tested; the preset planar geometric relationship is defined as the distance between the lines connecting the three laser points perpendicularly projected onto the sample stage forming a right triangle, and the molecule to be tested is located at the midpoint of the hypotenuse of the right triangle.

[0024] In this embodiment, the preset planar geometric relationship refers to forming a right triangle with three laser points as vertices and the distance between the lines connecting the three laser points as the side length, with the molecule to be tested located at the midpoint of the hypotenuse of the right triangle. According to the properties of a right triangle, when the molecule to be tested is located at the midpoint of the hypotenuse, the distance from the molecule to the three laser points is equal. Therefore, given the coordinates of the three laser points and the distances from the molecule to the three laser points, the coordinates of the molecule to be tested can be easily calculated.

[0025] In practical applications, the molecule to be tested undergoes dynamic changes due to various factors, causing its position to shift. To determine the position of the molecule during these dynamic changes, this embodiment requires continuously adjusting the positions of the three laser points to follow the molecule's trajectory. Specifically, the positions of the three laser points can be controlled by measuring the distances between them and the molecule.

[0026] Preferably, by acquiring the fluorescence of the molecule to be tested, a photon counter is used to collect the distance between each of the laser points and the fluorescence to obtain the distances between the three laser points and the molecule to be tested. The photon counter can employ, for example, an avalanche diode to calculate the distance between the laser and the fluorescence-producing molecule. This is based on the principle that when the laser is closer to the molecule, the molecule receives more laser energy, resulting in stronger fluorescence intensity. Conventional techniques can be used for this calculation, which will not be elaborated upon here.

[0027] Step S30: Each time a preset planar geometric relationship is formed, the coordinates of the three laser points and their distances to the molecule under test are obtained, and the coordinates of the molecule under test are calculated using the preset planar geometric relationship, thereby obtaining multiple coordinates of the molecule under test during the dynamic changes of the molecule under test when the preset planar geometric relationship is formed multiple times.

[0028] Specifically, when a predetermined planar geometric relationship is formed between the three laser points and the molecule to be tested, based on the properties of a right triangle, the median to the hypotenuse of the right triangle is equal to half the length of the hypotenuse, and the position of the molecule to be tested projected onto the right-angled side is located at the midpoint of the length of the right-angled side. Therefore, given the coordinates of the three laser points, the coordinates of the molecule to be tested can be obtained using a simple formula.

[0029] For example, let the positions of the three laser points form Figure 3 The diagram shows a right-angled triangle with three laser points denoted as A, B, and C, where laser point B is the right-angle vertex. The molecule to be measured is denoted as N, located at the midpoint of the hypotenuse of the right-angled triangle. A Cartesian coordinate system is obtained by extending BA as the Y-coordinate and extending BC as the X-coordinate. Let the coordinates of laser point A be (a1, a2), laser point B be (b1, b2), and laser point C be (c1, c2). Then, the coordinates of the molecule to be measured, N, are (n1, n2). Therefore, n1 = (c1 - b1) / 2 + b1, and n2 = (a2 - b2) / 2 + b2. This formula is extremely simple and can be implemented using a general-purpose microcontroller, effectively solving the problem that most existing algorithms for dynamically tracking molecule positions rely on complex probability distribution calculations, leading to insufficient computing power or resources.

[0030] Furthermore, it also includes step S40: plotting the motion trajectory curve of the dynamic change of the molecule under test based on multiple coordinates obtained during the dynamic change process of the molecule under test.

[0031] Of course, the corresponding time can be obtained each time a preset planar geometric relationship is formed, and the motion trajectory curve can be plotted by analyzing the relationship between time and coordinates. This motion trajectory curve can be used to analyze the motion state of single molecules, such as their velocity.

[0032] Preferably, to avoid the possibility that the plotted motion curve may not accurately reflect the actual motion due to a small number of coordinate points of the molecule to be tested, this embodiment can use interpolation methods (such as linear interpolation, polynomial interpolation, Lagrange interpolation, Newton interpolation), curve fitting, data smoothing, etc. to smooth the curve so that the plotted motion curve can accurately reflect the actual motion. The specific method used can be reasonably selected according to the actual application scenario, data characteristics, and accuracy requirements, and is not limited here.

[0033] It should be noted that, based on the concept of this invention, those skilled in the art can also apply this method to ion trajectory analysis, particle trajectory analysis, and other applications.

[0034] In an alternative embodiment, such as Figure 2 As shown, adjusting the positions of the three laser points to ensure that the three laser points and the molecule to be tested repeatedly form a preset planar geometric relationship during the dynamic changes of the molecule to be tested includes the following steps: Step S21: Obtain the distance between the current three laser points and the molecule to be tested.

[0035] Step S22: Compare the pairwise distances between the current three laser points and the molecule to be tested.

[0036] Step S23: The coordinate values ​​of the three laser points are corrected by comparing the differences between the distances between the three current laser points and the molecules to be tested, and by combining the preset planar geometric relationship.

[0037] Step S24: Adjust the positions of the three laser points according to the corrected coordinate values ​​of the three laser points until the preset planar geometric relationship is formed between the three laser points and the molecule to be tested.

[0038] Specifically, such as Figure 3 As shown, the positions of the three laser points are defined as A, B, and C, and the position of the molecule to be tested is defined as N. The distances between the three laser points and the molecule to be tested are denoted as L. NA L NB L NCWhen the distance between the lines connecting the three laser points forms a right triangle, let laser point B be the right-angle vertex of the right triangle, take the extension of BA as the Y-coordinate direction and the extension of BC as the X-coordinate direction to obtain a plane rectangular coordinate system. The formula for comparing the pairwise distances between the three current laser points and the molecule to be tested, and correcting the coordinate values ​​of the three laser points by comparing the differences between the pairwise distances between the three current laser points and the molecule to be tested, combined with the preset planar geometric relationship, is as follows: If L NA >L NB Then, the Y coordinate values ​​of the current three laser points A, B, and C are each reduced by (L). NA -L NB )*β, to obtain the corrected Y coordinate values ​​of the three laser points A, B, and C; If L NA <L NB Then, the Y coordinate values ​​of the three current laser points A, B, and C are each increased by (L... NB -L NA )*β, to obtain the corrected Y coordinate values ​​of the three laser points A, B, and C; If L NC >L NB Then, the X coordinate values ​​of the current three laser points A, B, and C are each reduced by (L). NC -L NB )*β, to obtain the corrected X coordinate values ​​of the three laser points A, B, and C; If L NC <L NB Then, the X coordinate values ​​of the three current laser points A, B, and C are each increased by (L). NB -L NC )*β, to obtain the corrected X coordinate values ​​of the three laser points A, B, and C; If L NA =L NB =L NC This indicates that the correction is complete; In the formula, β represents the adjustment coefficient, which is obtained based on factors such as laser intensity, laser irradiation time, and molecular velocity. It should be noted that the adjustment coefficient β needs to be determined based on the actual application scenario, considering factors such as laser intensity, laser irradiation time, molecular velocity, and even the accuracy requirements of the molecule being tested; no specific limitation is made here. The simplest way to determine it is through a finite number of experiments. That is, by determining the coordinates of the current three laser points and the corrected three laser points, as well as the coordinates of the current molecule being tested and the coordinates of the molecule being tested after its movement, the value of the adjustment coefficient β is derived in reverse.

[0039] Furthermore, in the preset planar geometric relationship, the right triangle formed by the distance between the lines connecting the three laser points is an isosceles right triangle. By limiting the isosceles right triangle, the difficulty of adjusting the laser points is further reduced, and the efficiency is improved.

[0040] Based on the above inventive concept, those skilled in the art can also define the preset planar geometric relationship as other relationships that have a clear correlation between the positions and distances of multiple laser points and the molecule under test on the vertical projection, in terms of lines, planes, or angles, so that the coordinates of the molecule under test can be calculated using the preset planar geometric relationship when the coordinates of multiple laser points and the distances between multiple laser points and the molecule under test are known.

[0041] For example, when there are two laser points, the preset planar geometry can be set as follows: the molecule to be tested is located at the midpoint of the distance between the two laser points perpendicularly projected onto the sample stage. When there are three laser points, the preset planar geometry can be set as follows: the distance between the three laser points perpendicularly projected onto the sample stage forms an equilateral triangle, and the molecule to be tested is located at the center of the equilateral triangle. When there are four laser points, the preset planar geometry can be set as follows: the distance between the four laser points perpendicularly projected onto the sample stage forms a square, and the molecule to be tested is located at the midpoint of the square; or, the distance between the three laser points perpendicularly projected onto the sample stage forms an equilateral triangle, and the molecule to be tested is located at the center of the equilateral triangle, etc. The preset planar geometry schemes provided above can also calculate the coordinates of the molecule to be tested, and they also fall within the protection scope of this invention.

[0042] Of course, compared with the above-mentioned preset planar geometric relationship scheme, the use of three laser points to form a right triangle in this embodiment can greatly reduce the amount of calculation and improve the calculation efficiency.

[0043] In other alternative implementations, if the above-described schemes regarding the preset planar geometric relationship are adopted, adjusting the multiple laser points to form the preset planar geometric relationship can also be done in the following ways: Obtain the distances between multiple current laser points and the molecule to be measured; The distance between each laser point and the molecule to be tested is compared with the distance between the laser point and the molecule to be tested when the preset planar geometric relationship is formed; If there is a difference between the distances between each laser point and the molecule under test when the distances form the preset planar geometric relationship, then the coordinates of the laser points are corrected using the difference until the preset planar geometric relationship is formed between multiple laser points and the molecule under test. The specific formula can be reasonably derived and calculated based on the actual planar geometric relationship and the difference relationship.

[0044] Example 2 The present invention also provides a single-molecule dynamic tracking system based on laser positioning, which includes at least a sample stage, a laser emission module, an adjustment module and a calculation module.

[0045] The sample stage is used to place the analyte molecules; The laser emitting module is used to emit three laser points that are vertically projected onto the sample stage; The adjustment module is used to adjust the position of the three laser points so that the three laser points and the molecule to be tested form a preset planar geometric relationship multiple times during the dynamic change of the molecule to be tested; the preset planar geometric relationship is defined as the distance between the lines connecting the three laser points perpendicularly projected onto the sample stage forming a right triangle, and the molecule to be tested is located at the midpoint of the hypotenuse of the right triangle. The calculation module is used to obtain the coordinates of the three laser points and their distances from the molecule to be tested each time a preset planar geometric relationship is formed, and to calculate the coordinates of the molecule to be tested using the preset planar geometric relationship.

[0046] In one embodiment, a control module is further included, electrically connected to the laser emission module, the adjustment module, and the calculation module, respectively. The control module can control the laser emission module to emit laser points, and can also control the adjustment module to adjust the position of the laser points based on the collected distance data between the laser points and the molecule to be tested. Preferably, a communication module based on a USB interface, Bluetooth, or WIFI may also be included to transmit the calculated coordinate data of the molecule to be tested to a host computer.

[0047] In other optional embodiments, a plotting module is also included, which is used to plot the motion trajectory curve of the dynamic change of the molecule under test based on multiple coordinates acquired during the dynamic change process of the molecule under test, thereby facilitating subsequent motion trajectory analysis of the molecule under test.

[0048] In summary, compared with existing technologies, the laser-based single-molecule tracking method and system provided by this invention effectively avoids complex probability distribution calculation algorithms. It can dynamically track the position of molecules through simple adjustments and calculations, making it suitable for devices with limited computing resources such as microcontrollers. This effectively reduces computing costs and improves the accuracy and efficiency of molecule position tracking, showing promising application prospects.

[0049] Furthermore, those skilled in the art should understand that although many problems exist in the prior art, each embodiment or technical solution of the present invention can be improved in only one or a few aspects, without necessarily solving all the technical problems listed in the prior art or background art simultaneously. Those skilled in the art should understand that any content not mentioned in a claim should not be construed as a limitation on that claim.

[0050] Although this paper frequently uses terms such as analyte molecule, laser point, planar geometric relationship, adjustment coefficient, sample stage, laser emission module, adjustment module, calculation module, and plotting module, the possibility of using other terms is not excluded. These terms are used merely for the convenience of describing and explaining the essence of the invention; interpreting them as any kind of additional limitation would contradict the spirit of the invention. The terms "first," "second," etc. (if present), in the specification, claims, and accompanying drawings of the embodiments of the invention are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence.

[0051] 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 or all of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A single-molecule dynamic tracking method based on laser positioning, characterized in that, Includes the following steps: Three laser points are emitted vertically onto a sample stage containing the molecule to be tested; The positions of the three laser points are adjusted so that the three laser points and the molecule to be tested form a preset planar geometric relationship multiple times during the dynamic change of the molecule to be tested; the preset planar geometric relationship is defined as the distance between the lines connecting the three laser points that are perpendicularly projected onto the sample stage forming a right triangle, and the molecule to be tested is located at the midpoint of the hypotenuse of the right triangle; The step of adjusting the positions of the three laser points to ensure that a preset planar geometric relationship is formed between the three laser points and the molecule under test multiple times during the dynamic changes of the molecule under test includes the following steps: Obtain the distances between the three laser points and the molecule to be tested; Compare the pairwise distances between the three laser points and the molecule to be tested; The coordinate values ​​of the three laser points are corrected by comparing the differences between the pairwise distances between the three laser points and the molecule to be tested, and by combining the preset planar geometric relationship. Adjust the positions of the three laser points according to the corrected coordinate values ​​of the three laser points until the preset planar geometric relationship is formed between the three laser points and the molecule to be tested. Each time the preset planar geometric relationship is formed, the coordinates of the three laser points are obtained, and the coordinates of the molecule under test are calculated using the preset planar geometric relationship, thereby obtaining multiple coordinates of the molecule under test during the dynamic change process when the preset planar geometric relationship is formed multiple times.

2. The single-molecule dynamic tracking method based on laser positioning according to claim 1, characterized in that, It also includes the step of: plotting the motion trajectory curve of the dynamic change of the molecule under test based on the multiple coordinates obtained during the dynamic change process of the molecule under test.

3. The single-molecule dynamic tracking method based on laser positioning according to claim 1, characterized in that: By acquiring the fluorescence of the molecule to be tested, and using a photon counter to collect the distance between each of the laser points and the fluorescence, the distances between the three laser points and the molecule to be tested are obtained.

4. The single-molecule dynamic tracking method based on laser positioning according to claim 3, characterized in that: The positions of the three laser points are defined as A, B, and C, and the position of the molecule to be tested is defined as N. The distances between the three laser points and the molecule to be tested are denoted as L. NA L NB L NC When the distance between the three laser points forms a right triangle, laser point B is taken as the right-angle vertex of the right triangle, and the extension of BA is taken as the Y-coordinate direction and the extension of BC is taken as the X-coordinate direction to obtain a plane rectangular coordinate system. The formula for comparing the pairwise distances between the three laser points and the molecule to be tested, and correcting the coordinate values ​​of the three laser points by combining the differences between the pairwise distances between the three laser points and the molecule to be tested with the preset planar geometric relationship, is as follows: If L NA >L NB Then, the Y coordinate values ​​of the current three laser points A, B, and C are each reduced by (L). NA -L NB )*β, to obtain the corrected Y coordinate values ​​of the three laser points A, B, and C; If L NA <L NB Then, the Y coordinate values ​​of the three current laser points A, B, and C are each increased by (L... NB -L NA )*β, to obtain the corrected Y coordinate values ​​of the three laser points A, B, and C; If L NC >L NB Then, the X coordinate values ​​of the current three laser points A, B, and C are each reduced by (L). NC -L NB )*β, to obtain the corrected X coordinate values ​​of the three laser points A, B, and C; If L NC <L NB Then, the X coordinate values ​​of the three current laser points A, B, and C are each increased by (L). NB -L NC )*β, to obtain the corrected X coordinate values ​​of the three laser points A, B, and C; If L NA =L NB =L NC This indicates that the correction is complete; In the formula, β represents the adjustment coefficient, which is obtained based on factors such as laser intensity, laser irradiation time, and molecular motion speed.

5. The single-molecule dynamic tracking method based on laser positioning according to any one of claims 1-4, characterized in that: In the preset planar geometric relationship, the right triangle formed by the distance between the lines connecting the three laser points is an isosceles right triangle.

6. A single-molecule dynamic tracking system based on laser positioning, characterized in that, include: The sample stage is used to place the molecules to be tested. A laser emitting module is used to emit three laser points that are vertically projected onto the sample stage; An adjustment module is used to adjust the positions of the three laser points so that the three laser points and the molecule to be tested repeatedly form a preset planar geometric relationship during the dynamic changes of the molecule to be tested. The preset planar geometric relationship is defined as the distance between the lines connecting the three laser points perpendicularly projected onto the sample stage forming a right triangle, and the molecule to be tested is located at the midpoint of the hypotenuse of the right triangle. The adjustment of the positions of the three laser points so that the three laser points and the molecule to be tested repeatedly form the preset planar geometric relationship during the dynamic changes of the molecule to be tested includes: obtaining the current distance between the three laser points and the molecule to be tested; comparing the pairwise distances between the three laser points and the molecule to be tested; correcting the coordinate values ​​of the three laser points by comparing the differences between the pairwise distances between the three laser points and the molecule to be tested and combining them with the preset planar geometric relationship; and adjusting the positions of the three laser points according to the corrected coordinate values ​​of the three laser points until the preset planar geometric relationship is formed between the three laser points and the molecule to be tested. The calculation module is used to obtain the coordinates of the three laser points each time the preset planar geometric relationship is formed, and to calculate the coordinates of the molecule to be tested using the preset planar geometric relationship.

7. The single-molecule dynamic tracking system based on laser positioning according to claim 6, characterized in that: It also includes a drawing module, which is used to draw the motion trajectory curve of the dynamic change of the molecule under test based on multiple coordinates obtained during the dynamic change process of the molecule under test.

8. The single-molecule dynamic tracking system based on laser positioning according to claim 6, characterized in that: It also includes a control module, which is electrically connected to the laser emission module, adjustment module, and calculation module, respectively.

9. The single-molecule dynamic tracking system based on laser positioning according to claim 6, characterized in that: It also includes a communication module, which is used to transmit the coordinate data of the molecule to be tested calculated in the calculation module to the host computer.

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