CN102967834A - Device and method for magnetic resonance engine - Google Patents

Abstract

The invention discloses a magnetic resonance engine device. One end of a first valve is connected to one end of a first pipeline, and the other end of the first pipeline is provided with a semi-permeable membrane. The first valve and the second valve are connected through a second pipeline. A detection coil is sleeved, the outlet of the compression pump, the second valve and the third valve are respectively connected to the three channels of the tee, and the third valve is connected to the vacuum pump through a third pipeline. Also disclosed is a magnetic resonance engine method, in which the hyperpolarized inert gas penetrates into the PFA from the semi-permeable membrane under the action of negative pressure; gradually compresses the space of the cavity; conducts nuclear magnetic resonance sampling for high-concentration gas; and extracts the residual gas row away. The invention has simple structure and convenient operation. After the hyperpolarized inert gas is collected and compressed, the signal intensity of the hyperpolarized inert gas can be further improved by increasing the sample concentration of the hyperpolarized inert gas in the detection coil.

Description

A magnetic resonance engine device and method

technical field

The invention belongs to the field of nuclear magnetic resonance spectroscopy, and more specifically relates to a surge impact test device and a magnetic resonance engine method, which is suitable for hyperpolarized inert gas nuclear magnetic resonance.

Background technique

So far, commercial nuclear magnetic resonance spectrometers have been very mature, typically products from companies such as Bruker in Germany and Agilent in the United States. The NMR spectrometer first applies an electromagnetic wave of a specific frequency to the sample in a strong magnetic field through a coil. After the sample absorbs the electromagnetic wave of a specific frequency and undergoes a relaxation process, it will radiate an electromagnetic wave of a certain frequency. The coil and electronic circuit can convert and process the electromagnetic wave radiated by the sample to obtain the final magnetic resonance signal.

H核在磁场中由波尔兹曼分布决定的热平衡极化度P_H＝10₅~10₆，而由激光光泵和自旋交换技术可以将惰性气体核的极化度P_noble□gas提高10000倍以上，因此，激光产生的非平衡核自旋极化惰性气体的核磁共振信号大大的强于热平衡极化的质子信号，使得它们可能成为重要的生物和医学新诊断技术的造影剂。In recent years, the use of hyperpolarized noble gas techniques to enhance NMR sensitivity has become a popular research area in NMR spectroscopy. The NMR signal intensity (S) is proportional to the polarization degree P ₀ of the sample nucleus, namely:

The thermal equilibrium polarizability P _H of H nuclei determined by the Boltzmann distribution in the magnetic field is 10 ₅ ~10 ₆ , while the polarizability P _{noble gas} of inert gas nuclei can be increased by laser optical pumping and spin exchange technology More than 10,000 times, therefore, the nuclear magnetic resonance signals of non-equilibrium nuclear spin-polarized inert gases produced by lasers are much stronger than the proton signals of thermal equilibrium polarization, making them possible to become important contrast agents for new diagnostic techniques in biology and medicine.

At present, for the detection method of hyperpolarized inert gas magnetic resonance signals, the optical pump spin exchange polarization device is usually used to generate hyperpolarized inert gas, which is directly transported to the PFA tube in the detection coil, and then used The detection coil obtains the nuclear magnetic resonance signal of the hyperpolarized inert gas. The nuclear magnetic resonance signal of hyperpolarized inert gas is very strong, which also makes it successfully applied in many new aspects beyond the scope of traditional work, such as the use of hyperpolarized inert gas in lung MRI and brain functional imaging, in material science research The adsorption and chemical shift of laser polarized ¹²⁹ Xe can be used to study porous materials. In terms of chemistry, since the chemical shift of laser polarized ¹²⁹ Xe is particularly sensitive to the environment, hyperpolarized ¹²⁹ Xe is especially suitable for molecular probes.

However, the hyperpolarized noble gas NMR signal intensity detected in the experiment is often not as high as the signal intensity when it was produced. The main reasons include: 1) Due to the influence of the cleanliness of the collection device, pipeline, etc., material types, and paramagnetic substances, the polarization degree of some hyperpolarized inert gases will be lost; Due to the space limitation in the noble gas pipeline, the density of the arriving hyperpolarized noble gas signal is low; 3) Although the optical pump spin exchange working gas used in the experiment is a high-pressure mixed gas, such as 5atm ⁸ , the mixed gas usually consists of The main components of the NFC include pressure-increasing gas ⁴ He and fluorescence quenching gas N ₂ , while the content of inert gas is only 1-3%, that is, the amount of hyperpolarized inert gas generated is limited. For newer applications such as human lung MRI and biological probes, how to increase the amount or pressure of hyperpolarized inert gas and further enhance the hyperpolarized inert gas NMR signal in detection is an urgent problem to be solved.

The magnetic resonance engine of the present invention mainly increases the concentration (density or pressure) of the hyperpolarized inert gas by compressing the mixed gas, separating the mixed gas, and compressing the hyperpolarized inert gas, aiming to provide a further hyperpolarized inert gas NMR Signal method.

Contents of the invention

The purpose of the present invention is to solve the above problems in the prior art, provide a surge impact test device, and also provide a magnetic resonance engine method, the device is simple in structure, easy to operate, and can collect hyperpolarized inert gas and after compression, by increasing the hyperpolarized inert gas sample concentration in the detection coil, the signal intensity of the hyperpolarized inert gas is further increased.

In order to achieve the above object, the present invention adopts the following technical solutions:

A magnetic resonance engine device, comprising a first valve, a second valve, a third valve, a vacuum pump, a compression pump and a compression pump controller, one end of the first valve is connected to one end of a first pipeline, and the other end of the first pipeline is provided with a semi-permeable The first valve and the second valve are connected through the second pipeline, the second pipeline is covered with a detection coil, the outlet of the compression pump, the second valve and the third valve are respectively connected to the three channels of the tee, and the third valve It is connected with the vacuum pump through the third pipeline.

A magnetic resonance engine device also includes a polarizer and a peristaltic pump, the polarizer is connected with the peristaltic pump, and the peristaltic pump is connected with the first pipeline through a semipermeable membrane.

The first pipe, the second pipe, the third pipe and the tee mentioned above are all perfluoroalkoxy vinyl ether resins.

A method for a magnetic resonance engine, comprising the steps of:

Step 1 (A), open the first valve, the second valve and the third valve, and start the vacuum pump until the vacuum degree in each pipe and valve in the device is lower than 4psi, and the piston of the compression pump is sucked to the nearest three due to the negative pressure. pass the process;

Step 2 (B), close the third valve, the hyperpolarized inert gas enters the first pipeline through the semi-permeable membrane, the compression pump controller controls the piston of the compression pump to move away from the tee, and the hyperpolarized inert gas fills the compression pump volume space;

Step 3 (C), close the first valve, the controller of the compression pump controls the piston of the compression pump to compress in the direction close to the tee, and press the hyperpolarized inert gas into the second pipeline between the first valve and the second valve, close the second valve;

Step 4 (D), start the detection coil to sample the hyperpolarized inert gas in the second pipeline;

Step 5 (E), after the sampling is completed, open the second valve and the third valve, pump the vacuum pump to extract the sampled inert gas out of the system, and return to step 1 to cycle until the sampling is stopped.

The hyperpolarized noble gas as described above ^is129Xe .

Compared with the prior art, the present invention has the following advantages and effects:

1. Improved the method of testing the hyperpolarized inert gas NMR signal in the mixed gas in the original experiment, which can separate the hyperpolarized inert gas from the mixed gas, and increase the sample density through the magnetic resonance engine technology;

2. It can overcome the problem of small filling factor Q value and weak signal due to the small inner diameter of the pipeline and low sample concentration, and can greatly enhance the magnetic resonance signal.

3. Different from the problem that radio frequency excitation and reception must be synchronized in the traditional nuclear magnetic resonance process, using the long longitudinal relaxation time T ₁ of hyperpolarized inert gas and good water solubility and fat solubility, radio frequency The two processes of excitation and reception are separated.

Description of drawings

Fig. 1 is a device connection diagram of the present invention;

Fig. 2 is a flow chart of the method of the present invention.

In the figure: 1-semipermeable membrane; 2-first valve; 3-detection coil; 4-vacuum pump; 5-compression pump controller; 6-compression pump; 7-second valve; 8-third valve; 9- 10-second pipeline; 11-third pipeline; 12-tee; 13-peristaltic pump; 14-polarizer.

Detailed ways

Below in conjunction with accompanying drawing, the present invention is described in further detail:

Implementation 1:

As shown in Figure 1, a kind of magnetic resonance engine device comprises a first valve 2, a second valve 7, a third valve 8, a vacuum pump 4, a compression pump 6 and a compression pump controller 5, one end of the first valve 2 is connected to the first One end of the pipeline 9 is connected, the other end of the first pipeline 9 is provided with a semi-permeable membrane 1, the first valve 2 and the second valve 7 are connected through the second pipeline 10, the second pipeline 10 is provided with a detection coil 3, and the compression pump 6 The outlet, the second valve 7 and the third valve 8 are respectively connected to the three channels of the tee 12 , and the third valve 8 is connected to the vacuum pump 4 through the third pipeline 11 .

A magnetic resonance engine device further includes a polarizer 14 and a peristaltic pump 13, the polarizer 14 is connected to the peristaltic pump 13, and the peristaltic pump 13 is connected to the first pipeline 9 through the semipermeable membrane 1.

The first pipe 9, the second pipe 10, the third pipe 11 and the tee 12 are all perfluoroalkoxy vinyl ether resins.

The hyperpolarized inert gas may include: hyperpolarized ³ He, hyperpolarized ⁸⁷ Kr, hyperpolarized ¹³¹ Xe and ¹²⁹ Xe, etc.

Example 2:

The hyperpolarized inert gas is ¹²⁹ Xe,

After the experiment started, at first the first valve 2, the second valve 7, and the third valve 8 were all kept open, and the vacuum pump 4 was started to suck all the air in the pipeline of the whole system to keep the vacuum degree lower than 4psi. If the air is drawn outside the system, the system will be in and maintain a negative pressure state. At this time, the piston of the compression pump 6 will be in its own state close to the three-way 12. When the system is in a vacuum state, the third valve 8 is closed to isolate the pipeline system from the vacuum system. Since the semipermeable membrane 1 is a one-way chemical membrane, it can only allow ¹²⁹ Xe gas molecules to pass through. When there is a pressure difference between the two ends of the membrane 1 , the hyperpolarized ¹²⁹ Xe gas in the hyperpolarized ¹²⁹ Xe solution will pass through the semipermeable membrane 1 and enter the first pipeline 9 . With the continuous inflow of ¹²⁹ Xe gas, the gas will gradually fill the volume space of the compression pump 6 , and the piston of the compression pump 6 will gradually move away from the tee 12 .

After the gas fills the volume space of the compression pump 6, close the first valve 2, so that ¹²⁹ Xe gas no longer enters the area on the right side of the first valve 2, and the compression pump controller 5 controls the piston of the compression pump 6 to compress the gas in the cavity. Make the ¹²⁹ Xe gas gradually enter the area between the first valve 2 and the second valve 7, at this time close the second valve 7, and start the detection coil 3 to sample the high-concentration hyperpolarized ¹²⁹ Xe gas in the second pipeline 10 .

Example 3:

A magnetic resonance engine method, comprising the steps of:

Step 1 (A), open the first valve 2, the second valve 7 and the third valve 8, and start the vacuum pump 4 until the vacuum degree in each pipeline and valve in the device is lower than 4psi, and the piston of the compression pump 6 is compressed due to negative pressure. Suction to the process closest to the tee 12;

Step 2 (B), close the third valve 8, the hyperpolarized inert gas enters the first pipeline 9 through the semi-permeable membrane 1, the compression pump controller 5 controls the piston of the compression pump 6 to move away from the tee 12, and the superpolarized inert gas The polarized inert gas fills the volume space of the compression pump 6;

Step 3 (C), close the first valve 2, the compression pump controller 5 controls the piston of the compression pump 6 to compress in the direction close to the tee 12, and press the hyperpolarized inert gas into the first valve 2 and the second valve 7 Between the second pipeline 10, close the second valve 7;

Step 4 (D), start the detection coil 3 to sample the hyperpolarized inert gas in the second pipeline 10;

Step 5 (E), after the sampling is completed, open the second valve 7 and the third valve 8, pump the sampled inert gas out of the system with the vacuum pump 4, and return to step 1 to cycle until the sampling is stopped.

The working process of the magnetic resonance engine is divided into four steps, namely: suction-compression-sampling-exhaust. Inhalation refers to the process in which the hyperpolarized inert gas in the solution penetrates from the semi-permeable membrane into the pipeline of PFA (Perfluoroalkoxy-perfluoroalkoxy vinyl ether resin) under negative pressure; when the compression pump When a sufficient amount of hyperpolarized inert gas in the cavity is collected, the compression pump gradually compresses the space of the cavity to maximize the concentration of hyperpolarized inert gas in the pipeline in the coil area; after the compression process is completed, the high-concentration gas is subjected to nuclear magnetic resonance Sampling; finally open the relevant valves, use a vacuum pump to pump out the residual gas, and then enter the next suction cycle, repeating itself. The working process of a magnetic resonance engine is very similar to a mechanical engine intake stroke-compression stroke-ignition stroke exhaust stroke.

The specific embodiments described herein are merely illustrative of the spirit of the invention. Those skilled in the art to which the present invention belongs can make various modifications or supplements to the described specific embodiments or adopt similar methods to replace them, but they will not deviate from the spirit of the present invention or go beyond the definition of the appended claims range.

Claims (5)

1. magnetic resonance engine apparatus, it is characterized in that: comprise the first valve (2), the second valve (7), the 3rd valve (8), vacuum pump (4), compression pump (6) and compression pump controller (5), the first valve (2) one ends are connected with the first pipeline (9) one ends, the first pipeline (9) other end is provided with semi-permeable diaphragm (1), the first valve (2) is connected by second pipe (10) with the second valve (7), be arranged with magnetic test coil (3) on the second pipe (10), the outlet of compression pump (6), the second valve (7) is connected with three passages of threeway (12) respectively with the 3rd valve (8), is connected by the 3rd pipeline (11) between the 3rd valve (8) and the vacuum pump (4).

2. a kind of magnetic resonance engine apparatus according to claim 1, it is characterized in that: also comprise polarizer (14) and peristaltic pump (13), polarizer (14) is connected with peristaltic pump (13), and peristaltic pump (13) is connected with the first pipeline (9) by semi-permeable diaphragm (1).

3. a kind of magnetic resonance engine shape device according to claim 1, it is characterized in that: described the first pipeline (9), second pipe (10), the 3rd pipeline (11) and threeway (12) are the perfluorinated alkoxy vinyl ether resin.

4. a method of utilizing the described device of claim 1 to carry out the magnetic resonance engine is characterized in that, may further comprise the steps:

Step 1(A), open the first valve (2), the second valve (7) and the 3rd valve (8), start vacuum pump (4), until the low vacuum in each pipeline and the valve is in 4psi in the device, the piston of compression pump (6) is because negative pressure is drawn to the process of the most close threeway (12);

Step 2(B), close the 3rd valve (8), hyperpolarized noble gas sees through semi-permeable diaphragm (1) and enters the first pipeline (9), the piston of compression pump controller (5) control compression pump (6) is to the direction motion away from threeway (12), and hyperpolarized noble gas is full of the volume space of compression pump (6);

Step 3(C), close the first valve (2), the piston of compression pump controller (5) control compression pump (6) is to the direction compression near threeway (12), hyperpolarized noble gas is pressed into second pipe (10) between the first valve (2) and the second valve (7), closes the second valve (7);

Step 4(D), start detection coil (3) is sampled to the hyperpolarized noble gas in the second pipe (10);

Step 5(E), after sampling finishes, open the second valve (7) and the 3rd valve (8), vacuum pump (4) will be sampled inert gas extraction system complete outside, return step 1 and circulate until stop to sample.

5. the method for a kind of magnetic resonance engine according to claim 4, it is characterized in that: described hyperpolarized noble gas is ¹²⁹Xe.

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