A light-induced dynamic nuclear polarization module, an NMR spectrometer, and its usage method

Abstract

A light-induced dynamic nuclear polarization module, an NMR spectrometer, and their usage method are disclosed. The module includes a flexible LED light source array and a sample tube disposed inside the flexible LED light source array. An radio frequency (RF) coil is also disposed between the sample tube and the flexible LED light source array. The sample tube is movably disposed within the RF coil, which is fixed within the flexible LED light source array. A first gap is formed between the sample tube and the RF coil, and a second gap is formed between the RF coil and the flexible LED light source array. The flexible LED light source array includes a hollow cylindrical flexible substrate. A plurality of LED light source particles are distributed on the inner surface of the flexible substrate, and these LED light source particles are used to irradiate the sample tube. By directly integrating the flexible LED light source array in a cylindrical shape inside the probe and directly irradiating the sample in the detection area, light loss caused by optical fiber coupling is avoided, and the uniformity of illumination is significantly improved. Furthermore, the illumination intensity can be controlled by controlling the driving current, achieving effective in-situ illumination.

Description

Technical Field

[0001] This invention relates to the field of nuclear magnetic resonance technology, and in particular to a light-induced dynamic nuclear polarization module, an NMR spectrometer, and a method for using them. Background Technology

[0002] Currently, the main method for irradiating samples with light during the light-induced dynamic nuclear polarization process in nuclear magnetic resonance (NMR) spectrometers is the in-situ light irradiation method achieved by light conduction. This method mainly uses components such as optical fibers, plane mirrors, and quartz light guides to conduct light from the light source to the sample inside the NMR spectrometer probe, thereby achieving in-situ detection when the light reaction occurs.

[0003] However, the aforementioned in-situ light irradiation method using optical transmission has some significant drawbacks: First, the extremely low light source coupling efficiency caused by the optical connection between the light-emitting device and the light-transmitting device, as well as the high transmission loss caused by the long transmission path of the light-transmitting device, result in low light intensity when the light source reaches the magnetic resonance sample, making this method unsuitable for light source irradiation requirements under complex conditions; second, since light-induced dynamic nuclear polarization requires the light source to uniformly irradiate the detection area of ​​the sample, the optical fiber inserted into the sample tube can only form a point light source, thus making it impossible to achieve completely uniform irradiation of the sample; third, since the optical fiber needs to be inserted into the sample tube, the optical fiber will be contaminated by the sample, and the magnetic field homogeneity of the sample area will be altered, reducing the NMR detection quality. Summary of the Invention

[0004] In view of the shortcomings of the prior art, the purpose of this invention is to provide a light-induced dynamic nuclear polarization module, an NMR spectrometer, and a method for using the same.

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

[0006] A light-induced dynamic nuclear polarization module includes a flexible LED light source array and a sample tube disposed inside the flexible LED light source array. A radio frequency (RF) coil is also disposed between the sample tube and the flexible LED light source array. The sample tube is movably disposed within the RF coil, and the RF coil is fixed within the flexible LED light source array. A first gap is formed between the sample tube and the RF coil, and a second gap is formed between the RF coil and the flexible LED light source array. The flexible LED light source array includes a hollow columnar flexible substrate, and a plurality of LED light source particles are distributed on the inner surface of the flexible substrate. The LED light source particles are used to irradiate the sample tube.

[0007] Furthermore, the inner surface of the flexible substrate is provided with a plurality of LED light source particles distributed along its axial and circumferential directions. Each LED light source particle includes a positive electrode and a negative electrode, with the positive electrodes facing the same direction and the negative electrodes facing the same direction.

[0008] Furthermore, the flexible substrate also includes a first busbar and a second busbar. The first busbar is disposed on the inner side of the flexible substrate, and the second busbar is disposed on the outer side of the flexible substrate. The positions of the first busbar and the second busbar coincide in space. The first busbar is electrically connected to the positive electrode of the LED light source particle, and the second busbar is electrically connected to the negative electrode of the LED light source particle.

[0009] Furthermore, the flexible substrate also includes a first pad and a second pad. The first pad is disposed on the inner side of the flexible substrate, and the second pad is disposed on the outer side of the flexible substrate. The positions of the first pad and the second pad coincide in space. The first pad is electrically connected to the first busbar, and the second pad is electrically connected to the second busbar.

[0010] Furthermore, the flexible substrate has a via at the position of the LED light source particle, and the negative electrode of the LED light source particle is electrically connected to the second busbar through the via.

[0011] Furthermore, the size of the first gap is less than 1 mm, and the size of the second gap is less than 1 mm.

[0012] Furthermore, the spacing between two adjacent LED light source particles distributed along the axial direction is greater than the spacing at which they make electrical contact; the spacing between two adjacent LED light source particles arranged along the circumferential direction is greater than the spacing at which they make electrical contact when the flexible substrate is bent.

[0013] An NMR spectrometer includes a probe, the probe including a light-induced dynamic nuclear polarization module, characterized in that it further includes a superconducting magnet, the probe being disposed within the internal pore of the superconducting magnet.

[0014] Furthermore, it also includes a driver, a console, and a control terminal that are electrically connected to each other; a first cable is electrically connected between the driver and the flexible LED light source array; a second cable is electrically connected between the console and the radio frequency coil; a third cable is electrically connected between the console and the control terminal; and a fourth cable is electrically connected between the console and the driver.

[0015] A method for using an NMR spectrometer, applicable to NMR spectrometers, characterized by comprising:

[0016] Step 101: The control terminal generates a control sequence and sends the control sequence to the console via the third cable;

[0017] Step 102: The console is used to generate radio frequency pulse signals and LED drive control signals according to the timing of the control sequence. The console sends the radio frequency pulse signals and the LED drive control signals to the radio frequency coil and the driver respectively through the second cable and the fourth cable.

[0018] Step 103: The driver generates an LED driving current signal according to the LED driving control signal, and sends the LED driving current signal to the flexible LED light source array through the first cable. The flexible LED light source array lights up the LED light source particles therein according to the LED driving current signal.

[0019] Step 104: The radio frequency coil sends a radio frequency pulse signal to the sample to be tested in the sample tube according to the radio frequency pulse signal, and receives the NMR signal generated by the sample to be tested in response to the radio frequency pulse signal, and sends the NMR signal to the control console through the second cable;

[0020] Step 105: The console converts the NMR signal into a digital signal and sends the digital signal to the control terminal for display via a third cable.

[0021] Furthermore, in step 101: the control sequence includes, in chronological order, a pre-saturation pulse command, a delay command, an angle excitation pulse command, an LED light pulse command, a radio frequency pulse command, and a sampling command.

[0022] The beneficial effects of this invention are:

[0023] 1. The present invention proposes a light-induced dynamic nuclear polarization module, which, by setting up a flexible LED light source array, can directly irradiate the sample to be tested in the sample tube at the center of the radio frequency coil, avoiding the loss of light caused by multiple optical elements and transmission paths during long-distance transmission, thereby improving the light utilization efficiency and ensuring that the light intensity can meet the needs of complex photochemical reactions.

[0024] 2. The present invention proposes a light-induced dynamic nuclear polarization module, which uses a flexible LED array arranged in a uniform and matrix manner to set LED light source particles. The light is irradiated around the NMR radio frequency coil and emitted inward in a cylindrical shape, so that the sample to be tested is uniformly irradiated.

[0025] 3. The photo-induced dynamic nuclear polarization module proposed in this invention, through the design of the first and second busbars, counteracts the static magnetic field effects caused by the circuit traces. This effectively reduces the interference of the light source module on the magnetic field of the nuclear magnetic resonance spectrometer, ensuring the accuracy and stability of the nuclear magnetic resonance signal.

[0026] 4. The photo-induced dynamic nuclear polarization module proposed in this invention separates the flexible LED light source array from the sample to be detected by setting the sample tube, and the flexible LED light source array is integrated inside the probe. Without any processing of the NMR sample tube, the sample to be detected can be directly placed into the NMR radio frequency coil for detection, thereby realizing automated sample detection.

[0027] 5. The light-induced dynamic nuclear polarization module proposed in this invention eliminates the need to insert additional materials such as optical fibers into the sample tube, thus saving the procedure of cleaning the optical fibers. The process is simple, convenient, and practical, avoiding the defects of existing methods where inserting optical fibers into the sample affects the uniformity of the magnetic field, thereby seriously affecting the quality of the detected NMR signal.

[0028] 6. The NMR spectrometer proposed in this invention adopts a modular design, integrating the light source inside the probe. Preferably, the optical drive module can also be integrated inside the probe, which greatly simplifies the structure of the optically induced dynamic nuclear polarization system. The modular design allows for convenient parameter adjustment of the light source and the driver, improving experimental efficiency and reducing the difficulty of complex optical path construction and debugging. Attached Figure Description

[0029] To more clearly illustrate the technical solutions in the embodiments of the 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 only some embodiments of the invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0030] Figure 1 This is a schematic diagram of a spectrometer according to the present invention;

[0031] Figure 2 This is an exploded view of a light-induced dynamic nuclear polarization module according to the present invention;

[0032] Figure 3 This is one of the schematic diagrams of a flexible LED light source array for a light-induced dynamic nuclear polarization module according to the present invention;

[0033] Figure 4 for Figure 3 Enlarged view of point A;

[0034] Figure 5 This is a second schematic diagram of a flexible LED light source array for a light-induced dynamic nuclear polarization module according to the present invention;

[0035] Figure 6 for Figure 5 Enlarged view of point B;

[0036] Figure 7This is a schematic diagram of the control sequence of a control terminal for a spectrometer according to the present invention.

[0037] In the figure, 11. Superconducting magnet; 12. Probe; 13. Photoinduced dynamic nuclear polarization module; 14. First cable; 15. Driver; 16. Control console; 17. Control terminal; 18. Second cable; 19. Third cable; 20. Fourth cable; 21. Sample tube; 22. RF coil; 23. Flexible LED light source array; 41. Flexible substrate; 42. LED light source particles; 43. First busbar; 44. Second busbar; 45. First pad; 46. Second pad; 47. Via. Detailed Implementation

[0038] The following is combined Figure 1-7 The present invention will be described in detail below.

[0039] A light-induced dynamic nuclear polarization module 13, such as Figure 1-2 As shown, the device includes a flexible LED light source array 23 and a sample tube 21 disposed inside the flexible LED light source array 23. A radio frequency coil 22 is also disposed between the sample tube 21 and the flexible LED light source array 23. The sample tube 21 is movably disposed inside the radio frequency coil 22. Part of the radio frequency coil 22 is fixed inside the flexible LED light source array 23. A first gap is formed between the sample tube 21 and the radio frequency coil 22, and a second gap is formed between the radio frequency coil 22 and the flexible LED light source array 23. The flexible LED light source array 23 includes a hollow columnar flexible substrate 41. A plurality of LED light source particles 42 are distributed on the inner surface of the flexible substrate 41. The LED light source particles 42 are used to irradiate the sample tube 21.

[0040] Existing technologies use in-situ light irradiation for sample detection via optical conduction. The optical fiber must be manually inserted into the sample tube 21 from outside the magnet of the NMR spectrometer and reliably secured. Then, the sample tube 21 with the optical fiber is manually placed into the magnet. The sample cannot be directly placed into the magnet for detection, thus hindering automated sample detection. This invention separates the flexible LED light source array 23 from the sample to be detected and integrates the flexible LED light source array 23 inside the probe 12. Without any processing of the sample tube 21, the sample can be directly placed into the RF coil 22 for detection, thereby enabling automated sample detection.

[0041] In this embodiment, a plurality of LED light source particles 42 are distributed on the inner side of the flexible substrate 41 along its axial and circumferential directions. Each LED light source particle 42 includes a positive electrode and a negative electrode. The positive electrodes of the plurality of LED light source particles 42 are oriented in the same direction, and the negative electrodes of the plurality of LED light source particles 42 are oriented in the same direction.

[0042] Specifically, the flexible LED light source array 23 is formed by rolling up a rectangular flexible substrate 41. The LED light source particles 42 are LED particles with the smallest package size. In this embodiment, 0201 packaged LED particles are used. The light emitted by the LED particles is blue light with a wavelength of 440nm to 470nm to cover the absorption wavelength range of the sample to be tested. The LED particles are arranged in a matrix on the inner side of the flexible substrate 41. Several LED particles are equidistantly distributed in the column direction of the matrix, that is, along the axial direction of the flexible substrate 41. The positive and negative poles of the LED particles in the column direction are arranged in the same way. Several LED particles are equidistantly distributed in the row direction of the matrix, that is, along the circumference of the flexible substrate 41. The positive and negative poles of the LED particles in the row direction are arranged in the same way to illuminate the sample tube 21 at the center of the radio frequency coil 22.

[0043] Existing technologies involve inserting optical fibers into the sample, which can lead to fiber contamination. This necessitates cleaning the fibers after each detection, a cumbersome and complex process that also alters the uniformity of the magnetic field in the sample area, severely impacting the quality of the detected NMR signal. This invention arranges LED light source particles 42 uniformly and in a matrix within a flexible LED light source array 23, illuminating the area around the RF coil 22. This eliminates the need for inserting optical fibers or other additional materials into the NMR sample tube 21, thus avoiding the need for cleaning the fibers. The process is simple, convenient, and practical, avoiding the drawbacks of existing methods where fiber insertion affects magnetic field uniformity and consequently, the quality of the detected NMR signal.

[0044] In this embodiment, as Figure 3-6 As shown, the flexible substrate 41 also includes a first busbar 43 and a second busbar 44. The first busbar 43 is disposed on the inner side of the flexible substrate 41, and the second busbar 44 is disposed on the outer side of the flexible substrate 41. The positions of the first busbar 43 and the second busbar 44 coincide in space. The first busbar 43 is electrically connected to the positive electrode of the LED light source particle 42, and the second busbar 44 is electrically connected to the negative electrode of the LED light source particle 42.

[0045] In this embodiment, as Figure 3-6 As shown, the flexible substrate 41 also includes a first pad 45 and a second pad 46. The first pad 45 is disposed on the inner side of the flexible substrate 41, and the second pad 46 is disposed on the outer side of the flexible substrate 41. The positions of the first pad 45 and the second pad 46 coincide in space. The first pad 45 is electrically connected to the first busbar 43, and the second pad 46 is electrically connected to the second busbar 44.

[0046] Specifically, the first pad 45 and the second pad 46 are both copper pads. The first busbar 43 and the first pad 45 electrically connected to it are disposed on the same side (i.e., the inner side or the outer side) of the flexible substrate 41, and the second busbar 44 and the second pad 46 electrically connected to it are disposed on the other side (i.e., the inner side or the outer side) of the flexible substrate 41.

[0047] In this embodiment, the flexible substrate 41 has a via 47 at the position of the LED light source particle 42, and the negative electrode of the LED light source particle 42 is electrically connected to the second busbar 44 through the via 47.

[0048] In this embodiment, the size of the first slit is less than 1 mm, and the size of the second slit is also less than 1 mm. Specifically, the second slit is the gap formed by the flexible substrate 41 and the radio frequency coil 22. The distance between the flexible substrate 41 and the sample tube 21 is equal to the thickness of the radio frequency coil 22, typically 1-2 mm. The length of the flexible substrate 41 exceeds the length of the radio frequency coil 22 to effectively illuminate all samples in the detection area.

[0049] In this embodiment, the interval between two adjacent LED light source particles 42 distributed along the axial direction is greater than the interval at which they make electrical contact; the interval between two adjacent LED light source particles 42 arranged along the circumferential direction is greater than the interval at which they make electrical contact when the flexible substrate 41 is bent.

[0050] Specifically, the spacing between two adjacent LED particles arranged in the axial direction should be such that they do not come into physical contact; similarly, the spacing between two adjacent LED particles arranged in the circumferential direction should be such that the two LED particles do not come into physical contact when the flexible substrate 41 is bent.

[0051] An NMR spectrometer, such as Figure 1 As shown, the device includes a probe 12, which includes a light-induced dynamic nuclear polarization module 13. The device is characterized by further including a superconducting magnet 11, with the probe 12 passing through an inner hole in the superconducting magnet 11. The superconducting magnet 11 has an inner hole adapted to accommodate the probe 12, and a portion of the probe 12 passes through the inner hole of the superconducting magnet 11.

[0052] In this embodiment, as Figure 1 As shown, it also includes a driver 15, a console 16, and a control terminal 17 that are electrically connected to each other; a first cable 14 is electrically connected between the driver 15 and the flexible LED light source array 23; a second cable 18 is electrically connected between the console 16 and the RF coil 22; a third cable 19 is electrically connected between the console 16 and the control terminal 17; and a fourth cable 20 is electrically connected between the console 16 and the driver 15.

[0053] Specifically, the first cable 14 and the fourth cable 20 are two-core copper cables, the second cable 18 is an RF coaxial cable, the third cable 19 is a network cable, and the control terminal 17 is a computer.

[0054] A method for using an NMR spectrometer, applicable to NMR spectrometers, characterized by comprising:

[0055] Step 101: Place sample tube 21 into probe 12. Sample tube 21 contains the sample to be tested. Control terminal 17 generates control sequence and sends control sequence to console 16 through third cable 19.

[0056] Step 102: The console 16 is used to generate radio frequency pulse signals and LED drive control signals according to the timing of the control sequence. The console 16 sends the radio frequency pulse signals and LED drive control signals to the radio frequency coil 22 and the driver 15 respectively through the second cable 18 and the fourth cable 20. The LED drive control signal is output to the driver 15 through the IO interface of the console 16.

[0057] Step 103: The driver 15 generates an LED driving current signal according to the LED driving control signal, and sends the LED driving current signal to the flexible LED light source array 23 through the first cable 14. The flexible LED light source array 23 lights up the LED light source particles 42 according to the LED driving current signal. The lighting duration is controlled by the lighting duration in the LED light pulse command in the control sequence, and the lighting start time is the start time in the LED light pulse command in the control sequence.

[0058] Step 104: The radio frequency coil 22 sends the radio frequency pulse signal to the sample to be tested in the sample tube 21, receives the NMR signal generated by the sample to be tested in response to the radio frequency pulse signal during the duration of the sampling command in the control sequence, and sends the NMR signal to the console 16 through the second cable 18.

[0059] Step 105: During the sampling control command in the control sequence, the radio frequency coil 22 in the probe 12 and the console 16 receive the dynamically nuclear polarized NMR signal. The console 16 converts the NMR signal into a digital signal and sends the digital signal to the control terminal 17 for display via the third cable 19, and displays it to the NMR spectrometer operator.

[0060] In this embodiment, in step 101: as Figure 7 As shown, the control sequence includes, in chronological order, a pre-saturation pulse command, a delay command, an angle excitation pulse command, an LED light pulse command, an RF pulse command, and a sampling command.

[0061] Specifically, the pre-saturation pulse command is as follows: Figure 7The Pre and Delay commands in the text are: Figure 7 The Delay and angle excitation pulse commands in the text are: Figure 7 The t1 and LED light pulse commands are as follows: Figure 7 The LED and RF pulse commands are as follows Figure 7 The RF and sampling commands in the text are Figure 7 FID in.

[0062] The above embodiments are only for illustrating the technical concept and features of the present invention, and are intended to enable those skilled in the art to understand and implement the present invention. They should not be construed as limiting the scope of protection of the present invention. All equivalent changes or modifications made in accordance with the spirit and essence of the present invention should be covered within the scope of protection of the present invention.

Claims

1. A light-induced dynamic nuclear polarization module, characterized in that, The application relates to a flexible LED light source array and a sample tube arranged inside the flexible LED light source array, wherein a radio frequency coil is arranged between the sample tube and the flexible LED light source array, the sample tube is movably arranged in the radio frequency coil, the radio frequency coil is fixed in the flexible LED light source array, a first gap is formed between the sample tube and the radio frequency coil, a second gap is formed between the radio frequency coil and the flexible LED light source array, the flexible LED light source array comprises a hollow columnar flexible substrate, a plurality of LED light source particles are distributed on the inner side of the flexible substrate, and the LED light source particles are used for irradiating the sample tube; the inner side of the flexible substrate is provided with a plurality of the LED light source particles in the axial direction and the circumferential direction, the LED light source particles comprise an anode and a cathode, the anodes have the same direction, and the cathodes have the same direction; the flexible substrate further comprises a first bus and a second bus, the first bus is arranged on the inner side of the flexible substrate, the second bus is arranged on the outer side of the flexible substrate, the positions of the first bus and the second bus coincide in space, the first bus is electrically connected to the anodes of the LED light source particles, and the second bus is electrically connected to the cathodes of the LED light source particles; the interval between two adjacent LED light source particles arranged in the axial direction is greater than the interval at which the two LED light source particles are in electrical contact; and the interval between two adjacent LED light source particles arranged in the circumferential direction is greater than the interval at which the two LED light source particles are in electrical contact when the flexible substrate is bent.

2. A light-induced dynamic nuclear polarization module as claimed in claim 1, characterized in that, The flexible substrate is provided with a via hole at the position of the LED light source particle, and the cathode of the LED light source particle is electrically connected to the second bus through the via hole.

3. A light-induced dynamic nuclear polarization module as claimed in claim 1, characterized in that, The size of the first gap is less than 1 mm, and the size of the second gap is less than 1 mm.

4. An NMR spectrometer comprising a probe, the probe comprising a light-induced dynamic nuclear polarization module as claimed in any one of claims 1-3, characterized in that, The application further comprises a superconducting magnet, and the probe is arranged in the inner hole of the superconducting magnet.

5. A NMR spectrometer as claimed in claim 4, characterised in that, The application further comprises a driver, a control console and a control terminal which are electrically connected to each other; the first cable is electrically connected between the driver and the flexible LED light source array; the second cable is electrically connected between the control console and the radio frequency coil; the third cable is electrically connected between the control console and the control terminal; and the fourth cable is electrically connected between the control console and the driver.

6. A method of using an NMR spectrometer as claimed in claim 5, characterized in that The application further comprises Step 101: the control terminal generates a control sequence and sends the control sequence to the control console through the third cable; Step 102: the control console generates a radio frequency pulse signal and an LED driving control signal according to the time sequence of the control sequence, and sends the radio frequency pulse signal and the LED driving control signal to the radio frequency coil and the driver through the second cable and the fourth cable respectively; Step 103: the driver generates an LED driving current signal according to the LED driving control signal, and sends the LED driving current signal to the flexible LED light source array through the first cable, so that the LED light source particles in the flexible LED light source array are lighted according to the LED driving current signal. Step 104: The radio frequency coil sends a radio frequency pulse signal to the sample to be detected in the sample tube, receives an NMR signal generated by the sample to be detected in response to the radio frequency pulse signal, and sends the NMR signal to the control console through a second cable; Step 105: The control console converts the NMR signal into a digital signal and sends the digital signal to the control terminal for display through a third cable.

7. A method of using an NMR spectrometer as claimed in claim 6, wherein, In the step 101: The control sequence includes, in chronological order, a pre-saturation pulse command, a delay command, an angle excitation pulse command, an LED light pulse command, a radio frequency pulse command, and a sampling command.

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