A smart system and method for improving the stability of surface-enhanced Raman spectroscopy signals.

Abstract

This invention discloses an intelligent system and method for improving the stability of surface-enhanced Raman (SMR) spectral signals, relating to the field of Raman spectroscopy detection technology. The invention uses a slide holder to hold a slide containing the SMR sample. After the heating tube is inserted into the hole, it automatically heats the sample. A rotating mechanism automatically rotates the heating tube and slide holder to a position below a microscope camera. The microscope camera captures a microscopic image of the sample. Based on this image, a computer determines the flow state of the sample. When the flow state is stable, a control chip disconnects the power supply circuit to stop the heating tube. This invention ensures that the sample is in a uniform flow state during each SMR spectrum measurement, thereby achieving the goal of obtaining more stable SMR spectra.

Description

Technical Field

[0001] This invention relates to the field of Raman spectroscopy detection technology, and in particular to an intelligent system and method for improving the stability of surface-enhanced Raman spectroscopy signals. Background Technology

[0002] Conventional Raman spectroscopy can enhance the Raman signal of samples adsorbed on colloidal metal particles such as silver, gold, or copper, or on the rough surfaces of these metal sheets, by three to four orders of magnitude. By preparing the sample as a liquid solution and mixing it with colloidal solutions of gold, silver, etc., the analyte molecules interact with the rough metal surface. Under laser irradiation, surface-enhanced Raman spectra of the sample are obtained due to electromagnetic and chemical enhancement mechanisms. This method is quick, simple, and easy to implement. However, if the sample is left for a long time, the measured Raman spectrum will change as the sample volatilizes. Because the pattern of this change is difficult to discern, the application of surface-enhanced Raman spectroscopy in quantitative detection is limited.

[0003] In the past, surface-enhanced Raman spectroscopy (SERS) was often used for qualitative analysis and quantitative analysis of small samples. However, with increasing demands for model robustness and larger sample sizes, it is difficult to guarantee consistent processing for obtaining SERS spectra every time, introducing random interference into the establishment of quantitative models. One significant interference is the flow state of the analyte. Since the analyte is a solution, it is in a constantly evaporating state, and the binding of nanoparticles and analyte molecules within it is constantly changing. This has an unknown impact on the Raman signal and reduces the applicability of SERS in quantitative detection. Summary of the Invention

[0004] The purpose of this invention is to provide an intelligent system and method for improving the stability of surface-enhanced Raman spectroscopy signals, so as to ensure that the sample is in a uniform flow state each time the surface-enhanced Raman spectrum of the sample is measured, thereby achieving the goal of obtaining a more stable surface-enhanced Raman spectrum.

[0005] To achieve the above objectives, the present invention provides the following solution:

[0006] A smart system for improving the stability of surface-enhanced Raman spectroscopy signals, the smart system comprising: a rotating mechanism, a control chip, a power supply circuit, a microscope camera, a computer, multiple heating tubes, and multiple glass slide boxes;

[0007] The rotating mechanism has multiple holes on its side, each of which can accommodate a heating tube; each heating tube is connected to a slide box at its end, which is used to hold a slide containing the surface-enhanced Raman test sample.

[0008] The power supply circuit is connected to the power supply terminal of each hole of the rotating mechanism. The power supply circuit is used to supply power to the heating tube after the heating tube is inserted into the hole, so that the heating tube starts to heat up and conducts heat to the sample to be tested in the slide box.

[0009] The control chip is connected to the rotation control terminal of the rotating mechanism, and the signal output terminal of the microscope camera is connected to the computer. The control chip is used to adjust the rotation angle according to the position of the inserted heating tube, ensuring that each rotation of the rotating mechanism rotates a slide box under the microscope camera. The microscope camera is used to capture a microscopic image of the sample to be tested in the slide box below and transmit the microscopic image of the sample to the computer. The computer is used to determine the flow state of the sample to be tested based on the microscopic image of the sample. The flow state includes steady state and unsteady state.

[0010] The input terminal of the control chip is connected to the computer, and the output terminal of the control chip is connected to the control terminal of the power supply circuit. The computer is also used to disconnect the power supply circuit through the control chip to stop the heating of the heating tube when the flow state of the sample to be tested is in a steady state.

[0011] A method for improving the stability of surface-enhanced Raman spectroscopy signals, the method employing the aforementioned intelligent system for improving the stability of surface-enhanced Raman spectroscopy signals, the method comprising:

[0012] All the samples to be tested were loaded into the slide box and heated by inserting the heating tube into the hole of the rotating mechanism.

[0013] The control chip automatically sets the rotation angle for each rotation based on the position of the inserted heating tube, ensuring that the slide box containing the sample to be tested moves directly below the microscope camera with each rotation.

[0014] After each rotation of the rotating mechanism according to the aforementioned rotation angle, the slide box is rotated under the microscope camera and remains there for a preset time.

[0015] Within a preset time period, two microscopic images of the sample to be tested are continuously captured by a microscope camera.

[0016] Calculate the difference between two microscopic images of the sample to be tested;

[0017] If the difference is greater than or equal to the difference threshold, the flow state of the sample to be tested is determined to be unsteady.

[0018] If the difference is less than the difference threshold, the flow state of the sample to be tested is determined to be steady state, and the heating tube corresponding to the sample to be tested is controlled to stop heating.

[0019] According to specific embodiments provided by the present invention, the present invention discloses the following technical effects:

[0020] This invention discloses an intelligent system and method for improving the stability of surface-enhanced Raman (SMR) spectral signals. A slide holder holds a SMR sample to be measured. After a heating tube is inserted into the hole, it automatically heats the sample. A rotating mechanism automatically rotates the heating tube and slide holder to a position below a microscope camera. The microscope camera captures a microscopic image of the sample. A computer determines the flow state of the sample based on this image. When the flow state is stable, a control chip disconnects the power supply to stop the heating tube. This invention ensures that the sample is in a uniform flow state during each SMR spectrum measurement, thereby achieving the goal of obtaining more stable SMR spectra. Attached Figure Description

[0021] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0022] Figure 1 A schematic diagram of the structure of an intelligent system for improving the stability of surface-enhanced Raman spectroscopy signals, provided in an embodiment of the present invention;

[0023] Figure 2 A flowchart illustrating a method for improving the stability of surface-enhanced Raman spectroscopy signals, provided in an embodiment of the present invention;

[0024] Figure 3 A schematic diagram illustrating a method for improving the stability of surface-enhanced Raman spectroscopy signals, provided by an embodiment of the present invention.

[0025] Figure 4 This is a flowchart for determining the flow state of a sample to be tested, provided in an embodiment of the present invention.

[0026] Figure 5 This is a control logic diagram for the working state of each heating element provided in an embodiment of the present invention;

[0027] Figure 6 This is a schematic diagram of a sample in a steady state and a sample in an unsteady state, taken at 1-second intervals under a 50x optical microscope according to an embodiment of the present invention. Figure 6 (a) in the image represents the sample in its steady-state state during the first photograph. Figure 6 (b) in the image shows the sample in its unsteady state during the first photograph. Figure 6 (c) in the image represents the sample in steady state, captured at 1-second intervals. Figure 6 (d) in the image represents a sample in a non-steady-state state, captured at 1-second intervals.

[0028] Figure 7 The black and white images provided in this embodiment of the invention are obtained by adaptive binarization of samples in steady state and samples in non-steady state, which were captured at 1-second intervals under a 50x optical microscope. Figure 7 (a) in the image is the binarized image of the sample in its first steady-state state. Figure 7 (b) in the image is the binarized image of the sample taken in its first unsteady state. Figure 7 (c) in the image is a binarized image of the sample in steady state taken at 1-second intervals. Figure 7 In the image, (d) represents the binarized image of the sample in an unsteady state, captured at 1-second intervals.

[0029] Figure 8 Micro Raman spectra and signal-to-noise ratios of the same sample in different states provided in embodiments of the present invention; Figure 8 In the image (a), the micro Raman spectrum of sample 1 in its steady state is shown. Figure 8 (b) in the image shows the micro Raman spectrum of sample 2 in its steady state. Figure 8 (c) in the image represents the micro Raman spectrum of sample 1 in its unsteady state. Figure 8 In the figure, (d) is the micro Raman spectrum of sample 2 in its unsteady state.

[0030] Symbol explanation: 1-rotating mechanism, 2-heating tube, 3-slide box, 4-support base, 5-microscope camera, 6-computer. Detailed Implementation

[0031] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0032] The purpose of this invention is to provide an intelligent system and method for improving the stability of surface-enhanced Raman spectroscopy signals, so as to ensure that the sample is in a uniform flow state each time the surface-enhanced Raman spectrum of the sample is measured, thereby achieving the goal of obtaining a more stable surface-enhanced Raman spectrum.

[0033] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0034] like Figure 1 As shown, the present invention provides an intelligent system for improving the stability of surface-enhanced Raman spectroscopy signals, comprising: a rotating mechanism 1, a control chip, a power supply circuit, a microscope camera 5, a computer 6, multiple heating tubes 2, and multiple glass slide boxes 3.

[0035] The rotating mechanism 1 has multiple holes on its side, each capable of housing a heating tube 2. Each heating tube 2 is connected to a slide holder 3 at its end, which holds a slide containing the surface-enhanced Raman spectroscopy (SERS) sample. A power supply circuit is connected to the energizing terminal of each hole in the rotating mechanism 1. This circuit powers the heating tube 2 after it is inserted, causing it to heat and transfer heat to the sample in the slide holder 3. A control chip is connected to the rotation control terminal of the rotating mechanism 1, and the signal output terminal of the microscope camera 5 is connected to a computer 6. The control chip adjusts the rotation angle based on the position of the inserted heating tube 2, ensuring that each rotation of the rotating mechanism 1 moves a slide holder 3 under the microscope camera 5. The microscope camera 5 captures a microscopic image of the sample in the slide holder 3 below and transmits this image to the computer 6. The computer 6 determines the flow state of the sample based on the microscopic image, including both steady-state and unsteady-state flows. The input terminal of the control chip is connected to the computer 6, and the output terminal of the control chip is connected to the control terminal of the power supply circuit. The computer 6 is also used to disconnect the power supply circuit through the control chip to stop the heating of the heating tube 2 when the flow state of the sample to be tested is steady.

[0036] If the sample to be tested is tea juice, then this invention can improve the stability of the enhanced Raman spectral signal on the surface of tea juice.

[0037] This system can observe the flow state of the Raman sample in the slide box 3, perform appropriate targeted drying on the Raman-enhanced sample to ensure that the sample is in a uniform flow state, and determine the reasonable time point for detecting the Raman-enhanced sample, thereby achieving the goal of obtaining a more stable surface Raman-enhanced spectrum.

[0038] The rotating mechanism 1 can accommodate an appropriate number of heating tubes 2 according to the number of samples, and a larger number of heating tubes 2 can be accommodated by replacing the rotating mechanism 1 with a larger one.

[0039] The slide box 3 is welded together with the heating tube 2. The heating tube 2 heats the slide box 3 through the heat energy generated by the Joule effect of the conductor, and the heating tube 2 heats the slide box 3 through the heat conduction of the metal, thereby heating the sample to be tested in the slide box 3.

[0040] Heating element 2 contains a coil. Heating is achieved by passing an electric current through it. The alternating current coil generates a changing magnetic field, which in turn induces a current on the surface of heating element 2. Thus, a heating process similar to that of an induction cooker occurs on heating element 2, thereby achieving the heating effect. Alternatively, heating element 2 can directly utilize the thermal effect of electric current, where current passing through a resistor generates heat to achieve heating.

[0041] Reference Figure 1The intelligent system also includes: a support base 4. The rotating mechanism 1 is mounted on the support base 4; the control chip and power supply circuit are both located inside the support base 4.

[0042] For example, the power supply circuit includes: a power supply, multiple power supply paths, and multiple current sensors. One end of each of the multiple power supply paths is connected to the power supply, and the other ends of each power supply path are respectively disposed in multiple holes; the control terminals of the multiple power supply paths are connected to a control chip. The multiple current sensors are used to detect the current in each of the multiple power supply paths respectively; the signal output terminals of the multiple current sensors are all connected to the control chip. After the heating tube 2 is inserted into the hole, the power supply terminal of the heating tube 2 is connected to the other end of the power supply path, and the power supply, power supply path, and heating tube 2 form a current-carrying circuit. The current sensors transmit the current detected in the current-carrying circuit to the control chip, and the control chip determines whether the heating tube is inserted into the hole by judging whether a current circuit has been formed in each hole. Specifically, two electrodes protrude from the hole inside the rotating mechanism 1, and two electrodes are recessed into one end of the heating tube 2. When the heating tube 2 is inserted into the rotating mechanism 1, the two pairs of electrodes will stick together under the action of magnetic force, so that the rotating mechanism 1 will supply power to the heating tube 2.

[0043] The connection between the control chip and the computer 6 is not limited; it can be wireless communication or serial communication, etc.

[0044] The system operates as follows: The user places the prepared Raman-enhanced sample onto a glass slide, loads an appropriate number of heating tubes 2 into the rotating mechanism 1 according to the number of slides, and places a glass slide into the slide box 3 at the end of the heating tube 2. The device is then started, and the rotating mechanism 1 begins to rotate at a fixed angle. When the rotating mechanism 1 rotates a sample to be tested to a position below the camera, it pauses for 1.5 seconds. During this pause, the microscope camera 5 takes two photographs at 1-second intervals.

[0045] like Figure 6 (c) and Figure 6 As shown in (d), in the "unsteady-state" state, only some pixels of the sample are clearly visible within the field of view of a 50x microscope, and the image is constantly changing. Figure 6 (a) and Figure 6 As shown in (b), all pixels of the sample in the "steady state" state are clearly visible, and the image remains basically unchanged.

[0046] This invention also provides a method for improving the stability of surface-enhanced Raman spectroscopy signals. The method utilizes the aforementioned intelligent system for improving the stability of surface-enhanced Raman spectroscopy signals, such as... Figure 2 and Figure 3 As shown, the method includes:

[0047] Step S1: Load all the samples to be tested into the slide box 3 one by one, and heat them by inserting the heating tube 2 into the hole of the rotating mechanism 1.

[0048] Step S2: The control chip automatically sets the rotation angle for each rotation based on the position of the inserted heating tube, ensuring that the sample-containing slide box moves directly below the microscope camera with each rotation.

[0049] Staff can also change this rotation angle via computer.

[0050] Step S3: After each rotation of the rotating mechanism 1 according to the rotation angle control, the slide box 3 is rotated under the microscope camera 5 and stays there for a preset time.

[0051] Step S4: During the preset dwell time, take two microscopic images of the sample to be tested in succession using the microscope camera 5.

[0052] Step S5: Calculate the difference between the two microscopic images of the sample to be tested.

[0053] The specific process is as follows:

[0054] The two microscopic images of the test samples are adaptively binarized and converted into black and white images; after adaptive binarization, they can be regarded as two matrices of size (m×n);

[0055] Using the formula Z=∑ i∈(0,m ] ,j∈(0,n ] ,i,j∈N [I1(i,j)XOR I2(i,j)] calculates the difference between two black and white images; where Z is the difference value, I1(i,j) and I2(i,j) are the pixel values ​​of the (i,j) pixel in the two black and white images respectively, i and j are both integers, and XOR means to perform a unique OR operation;

[0056] Based on the difference between the two black and white images, according to the formula Calculate the difference between two black and white images; where Z1 is the difference.

[0057] Obviously, the larger Z is, the lower the overlap between the two photos.

[0058] Step S6: If the difference is greater than or equal to the difference threshold, the flow state of the sample to be tested is determined to be unsteady.

[0059] Step S7: If the difference is less than the difference threshold, the flow state of the sample to be tested is determined to be steady state, and the heating tube 2 corresponding to the sample to be tested is controlled to stop heating.

[0060] set up If the two images are determined to overlap, and the flow state of the sample to be tested is considered to be "steady state", the system will control the heating tube 2 corresponding to the sample to stop heating; otherwise, if the two images are determined not to overlap, the flow state of the sample to be tested is considered to be "unsteady state", and the system will continue to heat the heating tube 2 corresponding to the sample.

[0061] The procedure for determining the flow state of the sample is as follows: Figure 4 As shown. The control logic for the operating state of each heating element 2 is as follows: Figure 5 As shown.

[0062] If the microscope camera 5 cannot observe the flow state of the sample particles, add a 5% (w / v) NaCl solution equal to the volume of the sample to the glass slide.

[0063] In one example, the preset dwell time is 1.5 seconds, the time interval between two frames captured by the microscope camera 5 is 1 second, and the difference threshold is 5%.

[0064] Figure 7 The binarized results of images of the sample in the "steady state" and the sample in the "non-steady state" taken at 1 second interval are shown. The Z1 of the sample images in the "steady state" and the sample images in the "non-steady state" are calculated. The Z1 of the sample image in the "steady state" is 2.41% < 5%, and the Z1 of the sample image in the "non-steady state" is 10.58% > 5%, which meets the criteria for determining the "steady state" and "non-steady state" of this invention. Figure 8 The paper displays two Raman spectra under "unsteady" and two under "steady" states. Notably, for the same Raman sample, the signal-to-noise ratio of the Raman spectrum obtained under the "steady" state is much higher than that obtained under the "unsteady" state. This means that the method proposed in this invention can significantly improve the quality and stability of surface-enhanced Raman spectral signals. Figure 8 In the figure, the horizontal axis Raman shift represents the Raman spectrum, and the vertical axis Intensity represents the intensity.

[0065] As demonstrated by the embodiments, the intelligent system with specific structure and algorithm proposed in this invention can be used to specifically dry the Raman sample, so that the sample is in a uniform flow state, thereby achieving the goal of obtaining a more stable surface-enhanced Raman spectrum.

[0066] The various embodiments in this specification are described in a progressive manner, with each embodiment focusing on its differences from other embodiments. Similar or identical parts between embodiments can be referred to interchangeably. For the systems disclosed in the embodiments, since they correspond to the methods disclosed in the embodiments, the descriptions are relatively simple; relevant parts can be referred to the method section.

[0067] This document uses specific examples to illustrate the principles and implementation methods of the present invention. The descriptions of the above embodiments are only for the purpose of helping to understand the method and core ideas of the present invention. Furthermore, those skilled in the art will recognize that, based on the ideas of the present invention, there will be changes in the specific implementation methods and application scope. Therefore, the content of this specification should not be construed as a limitation of the present invention.

Claims

1. A smart system for improving the stability of surface-enhanced Raman spectroscopy signals, characterized in that, The intelligent system includes: a rotating mechanism, a control chip, a power supply circuit, a microscope camera, a computer, multiple heating tubes, and multiple glass slide boxes; The rotating mechanism has multiple holes on its side, each of which can accommodate a heating tube; each heating tube is connected to a slide box at its end, which is used to hold a slide containing the surface-enhanced Raman test sample. The power supply circuit is connected to the power supply terminal of each hole of the rotating mechanism. The power supply circuit is used to supply power to the heating tube after the heating tube is inserted into the hole, so that the heating tube starts to heat up and conducts heat to the sample to be tested in the slide box. The control chip is connected to the rotation control terminal of the rotating mechanism, and the signal output terminal of the microscope camera is connected to the computer. The control chip is used to adjust the rotation angle according to the position of the inserted heating tube, ensuring that each rotation of the rotating mechanism rotates a slide box under the microscope camera. The microscope camera is used to capture a microscopic image of the sample to be tested in the slide box below and transmit the microscopic image of the sample to the computer. The computer is used to determine the flow state of the sample to be tested based on the microscopic image of the sample. The flow state includes steady state and unsteady state. The input terminal of the control chip is connected to the computer, and the output terminal of the control chip is connected to the control terminal of the power supply circuit. The computer is also used to disconnect the power supply circuit through the control chip to stop the heating of the heating tube when the flow state of the sample to be tested is in a steady state.

2. The intelligent system for improving the stability of surface-enhanced Raman spectral signals according to claim 1, characterized in that, The intelligent system also includes: a support base; The rotating mechanism is mounted on the support base; the control chip and power supply circuit are both located inside the support base.

3. The intelligent system for improving the stability of surface-enhanced Raman spectral signals according to claim 1, characterized in that, The power supply circuit includes: a power source, multiple power supply paths, and multiple current sensors; One end of each of the multiple power supply paths is connected to a power source, and the other ends of each power supply path are respectively set in multiple holes; the control terminals of the multiple power supply paths are connected to a control chip. Multiple current sensors are used to detect the current in multiple power supply paths, one by one; the signal output terminals of multiple current sensors are all connected to the control chip. After the heating tube is inserted into the hole, the power supply end of the heating tube is connected to the other end of the power supply path. The power supply, the power supply path and the heating tube form a power circuit. The current sensor transmits the current signal detected in the power circuit to the control chip. The control chip is used to determine whether a heating element has been inserted into the hole after receiving a current signal.

4. The intelligent system for improving the stability of surface-enhanced Raman spectral signals according to claim 1, characterized in that, The slide box is welded to the heating tube, which heats the slide box through the Joule effect of the conductor. The heating tube heats the slide box through the thermal conduction of the metal.

5. A method for improving the stability of surface-enhanced Raman spectroscopy signals, characterized in that, The method employs the intelligent system for improving the stability of surface-enhanced Raman spectral signals as described in any one of claims 1-4, and the method comprises: All the samples to be tested were loaded into the slide box and heated by inserting the heating tube into the hole of the rotating mechanism. The control chip automatically sets the rotation angle for each rotation based on the position of the inserted heating tube, ensuring that the slide containing the sample is moved directly below the microscope camera with each rotation. After each rotation of the rotating mechanism according to the aforementioned rotation angle, the slide box is rotated under the microscope camera and remains there for a preset time. Within a preset time period, two microscopic images of the sample to be tested are continuously captured by a microscope camera. Calculate the difference between two microscopic images of the sample to be tested; If the difference is greater than or equal to the difference threshold, the flow state of the sample to be tested is determined to be unsteady. If the difference is less than the difference threshold, the flow state of the sample to be tested is determined to be steady state, and the heating tube corresponding to the sample to be tested is controlled to stop heating.

6. The method for improving the stability of surface-enhanced Raman spectral signals according to claim 5, characterized in that, The calculation of the difference between the two microscopic images of the sample to be tested specifically includes: The two microscopic images of the sample to be tested are adaptively binarized and then converted into black and white images; Using the formula Z=∑ i∈(0,m],j∈(0,n],i,j∈N [I1(i,j)XOR I2(i,j)] calculates the difference between two black and white images; where Z is the difference value, I1(i,j) and I2(i,j) are the pixel values ​​of the (i,j) pixel in the two black and white images respectively, i and j are integers, and XOR means to perform a unique OR operation; Based on the difference between the two black and white images, according to the formula Calculate the difference between two black and white images; where Z1 is the difference.

7. The method for improving the stability of surface-enhanced Raman spectral signals according to claim 5, characterized in that, If the microscope camera cannot observe the flow state of the particles in the sample, then add a 5% (w / v) NaCl solution equal in volume to the sample on the slide.

8. The method for improving the stability of surface-enhanced Raman spectral signals according to claim 5, characterized in that, The preset dwell time is 1.5 seconds, and the time interval between two frames captured by the microscope camera is 1 second; The difference threshold is 5%.

Images