阅读说明：本技术 非侵入式活体电子自旋共振方法和系统 (Non-invasive in vivo electron spin resonance method and system ) 是由 周江 周明瑞 周彬 于 2018-07-04 设计创作，主要内容包括：本公开提供了一种通过非侵入式高压放电装置在活体或非活体生物样本内安全地产生不成对电子的方法,从而在不灌注或植入外源性顺磁物质的条件下,能够应用电子自旋共振(ESR)技术检测活体或非活体生物样本的组织结构和生理活动,并进一步地获取神经介质活动、生物分子代谢、受体及化学成份信息,从而构成非侵入式活体电子自旋共振波谱仪、三维成像仪和大脑-计算机接口(Electron Spin Resonance Spectrometer&Imaging-Brain Computer Interface,ESRI-BCI)系统。(The present disclosure provides a method for safely generating unpaired electrons in a living or non-living biological sample by a non-invasive high voltage discharge device, so that the tissue structure and physiological activities of the living or non-living biological sample can be detected by using an Electron Spin Resonance (ESR) technology without perfusion or implantation of an exogenous paramagnetic substance, and further the information of nerve medium activity, biomolecule metabolism, receptors and chemical components can be obtained, thereby constituting a non-invasive living Electron Spin Resonance Spectrometer, a three-dimensional imager and a Brain-Computer Interface (ESRI-BCI) system.)

1. A non-invasive in vivo Electron Spin Resonance (ESR) method, wherein non-paired electrons are safely generated in a living or non-living biological sample by non-invasive high-voltage discharge, and under the condition of no perfusion or implantation of exogenous paramagnetic substances, the ESR technology is used for detecting the tissue structure and physiological activity of the living or non-living biological sample, and further acquiring the information of nerve medium activity, biomolecule metabolism, receptors and chemical components, comprising:

a high voltage power supply (101), a non-invasive discharge unit (102), a radio frequency Radio (RF) source (103), a radio frequency resonator assembly (104), a radio frequency switch or coupling assembly (105), a radio frequency receiving and data sampling assembly (106), a static uniform magnetic field assembly (107), an optional three-dimensional gradient magnetic field assembly (108), wherein the radio frequency resonator assembly (104) contains the living or non-living biological sample (110) and is placed within the static uniform magnetic field and optional gradient magnetic field generated by the static uniform magnetic field assembly (107) and optional three-dimensional gradient magnetic field assembly (108), and is connected with the RF source (103) through the radio frequency switch or coupling assembly (105) to generate resonance at a set radio frequency; and

an Electron Spin resonance spectrometer, a three-dimensional imager, and a Brain-Computer Interface (electronic Spin resonance spectrometer & Imaging-Brain Computer Interface, ESRI-BCI) (109) that receives and processes data from the radio frequency receiving and data sampling assembly (106) to measure and visualize ESR resonance data by being in operable communication with the high voltage power supply (101), RF source (103), radio frequency switch or coupling assembly (105), radio frequency resonator assembly (104), static uniform magnetic field assembly (107), and optionally three-dimensional gradient magnetic field assembly (108), and further, may parse Brain neural activity signals from the ESR resonance data into a data stream that can be accepted by a Computer system;

the exogenous paramagnetic substances (exogenous paramagnetic species) include spin labels (spin probes), spin probes (spin probes), nano paramagnetic probes (nano paramagnetic probes), and paramagnetic contrast agents (paramagnetic contrast agents).

2. The ESR method as claimed in claim 1, wherein the high voltage power source (101) and the non-invasive discharge unit (102) can apply a positive polarity high voltage or a negative polarity high voltage to the living or non-living organism sample (110) through an air gap, and form a loop through the air gap, so that there is no need to place a conductor on the surface of the living or non-living organism sample (110) to achieve the non-invasive discharge, and the positive polarity high voltage or the negative polarity high voltage is a voltage capable of ionizing the air gap.

3. The ESR method as claimed in claim 1, wherein the high voltage power source (101) can apply the positive polarity high voltage through the non-invasive discharge unit (102) to deprive electrons from valence shells of molecules and/or anions in the living or non-living biological sample (110), thereby generating the unpaired electrons.

4. The ESR method according to claim 1, wherein the high voltage power source (101) can transfer a certain amount of isolated electrons in the identical fermi state, i.e. free electrons, to the living or non-living biological sample (110) by applying the negative polarity high voltage through the non-invasive discharge unit (102), and the free electrons are immediately captured by the positive terminal and/or the positive valence electron layer of the polar molecules in the living or non-living biological sample (110), thereby generating the unpaired electrons.

5. The method of generating the unpaired electrons according to claims 3 and 4, further characterized in that the conduction velocity of the high voltage discharge is the speed of light, and the unpaired electrons can be instantaneously loaded to related molecules and/or ions at any position in the living or non-living biological sample (110), so that the ESR technology can be applied to obtain the dynamic spatial distribution information of the unpaired electrons in the living or non-living biological sample (110), and the dynamic spatial distribution information can reflect the tissue structure and physiological activity of the living or non-living biological sample (110);

further, such factors as chemical bonds of related molecules and/or ions of the unpaired electron carrier, nuclear magnetic dipoles, electron magnetic dipoles and adjacent groups cause the effect of hyperfine splitting of the ESR spectrum, so that ESR technology can be applied to further obtain information on nerve medium activity, biomolecule metabolism, receptors and chemical components.

6. The RF source (103) of claim 1, operable in a Continuous Wave (Continuous Wave) mode or a Time Domain (Time Domain) pulse mode, with an operating frequency selected in the range of 300KHz ~ 300 GHz.

7. The static uniform magnetic field assembly (107) of claim 1 wherein the source of the static uniform magnetic field is a permanent magnet, a room temperature electromagnet or a superconducting electromagnet, said magnet being of a cylindrical closed type or a biplanar open type, and having a magnetic field strength selected within the range of 0.00001T ~ 10.7.7T to accommodate an ESR frequency of 300KHz ~ 300 GHz.

8. The living or non-living biological sample (110) of claim 1, wherein the sample is a body, tissue, organ or cell of a plant, animal or human.

9. The ESR method according to claim 1, further comprising the steps of:

(1) first placing said living or non-living biological subject (110) in an electrically isolated environment within said radio frequency resonator assembly (104) within said static uniform magnetic field assembly (107), wherein said living or non-living biological subject (110) has no detectable naturally occurring said unpaired electrons therein, as with other substances in nature;

(2) then starting the high-voltage power supply (101), applying the positive polarity high voltage or the negative polarity high voltage through the non-invasive discharge unit (102), generating the unpaired electrons in the living or non-living biological sample (110), wherein the polar molecules and/or ions in the living or non-living biological sample (110) make the sample have good conductors such as conductivity and nonmetal, so that the sample can store electric charges in an insulating environment and can be regarded as equivalent capacitance, and the biological capacitance effect can stably maintain the unpaired electrons in the living or non-living biological sample (110);

(3) then, turning off the high-voltage output of the high-voltage power supply (101), starting ESR working cycles, detecting the tissue structure and physiological activity of the living or non-living biological sample (110), and further acquiring information of nerve medium activity, biomolecule metabolism, receptors and chemical components, wherein each ESR working cycle comprises a radio frequency excitation sequence, an optional magnetic field gradient coding sequence and a radio frequency receiving data sampling sequence;

(4) finally, after the ESR working period is finished, the high-voltage power supply (101) is started again to enter the next cycle; the start and stop of the high voltage power supply (101) is interspersed in the gap of each ESR duty cycle, within each ESR duty cycle, the high voltage power supply (101) enters a quiescent state, stopping the activity of all high voltage driven devices to avoid electromagnetic interference with the ESR duty cycle, the ESRI-BCI (109) manages the high voltage output and ESR duty cycle by operably communicating with the high voltage power supply (101), RF source (103), radio frequency switch or coupling assembly (105), radio frequency resonator assembly (104), static uniform magnetic field assembly (107), and optionally three dimensional gradient magnetic field assembly (108), receives and processes data from the radio frequency reception and data sampling assembly (106) to measure and visualize ESR resonance data, resolve and process cerebral nerve signals.

10. A non-invasive in vivo Electron Spin Resonance Spectrometer, three-dimensional imager, and Brain-Computer Interface (Electron Spin Resonance Spectrometer & Imaging-Brain Computer Interface, ESRI-BCI) system, comprising:

a high voltage power supply (101), a non-invasive discharge unit (102), a radio frequency Radio (RF) source (103), a radio frequency resonator assembly (104), a radio frequency switch or coupling assembly (105), a radio frequency receive and data sampling assembly (106), a static uniform magnetic field assembly (107), an optional three-dimensional gradient magnetic field assembly (108), and an ESRI-BCI (109);

the ESRI-BCI (109) comprises an FPGA data processing and peripheral control module (109 _ A) and a human-computer interface computer (109 _ B);

the static uniform magnetic field component (107) comprises a static uniform magnetic field Coil driving module (107 _ A) and a static uniform magnetic field Coil, the static uniform magnetic field Coil is a pair of hollow Helmholtz coils (107 _ B), and the static uniform magnetic field component (107) can convert static uniform magnetic field intensity codes from the FPGA data processing and peripheral control module (109 _ A) into a static uniform magnetic field of 0.0001T ~ 0.0107T so as to adapt to ESR frequency of 3MHz-300 MHz;

the three-dimensional gradient magnetic field assembly (108) comprises an XYZ gradient magnetic field coil driving module (108 _ A) and an XYZ gradient magnetic field coil (108 _ B), wherein the XYZ gradient magnetic field coil (108 _ B) is a disk-type biplane gradient coil embedded in an inner diameter plane of the Helmholtz coil (107 _ B), and is formed by superposing an X gradient magnetic field coil (108 _ B _ Gx), a Y gradient magnetic field coil (108 _ B _ Gy) and a Z gradient magnetic field coil (108 _ B _ Gz) along the axial lead direction of the Helmholtz coil (107 _ B), and the three-dimensional gradient magnetic field assembly (108) can convert gradient magnetic field codes from the FPGA data processing and peripheral control module (109 _ A) into gradient magnetic fields so as to obtain two-dimensional or three-dimensional spatial distribution information of the unpaired electrons in the living or non-living biological sample (110);

the radio frequency resonator assembly (104) comprises a radio frequency transmit-receive resonant coil (104 _ a) being an air-core coil with an inner diameter equal to or less than the helmholtz coil (107 _ B) center-to-center spacing, the center plane of which is perpendicular to the plane of the helmholtz coil (107 _ B) and coplanar with the axial center line of the helmholtz coil (107 _ B);

the high-voltage power supply (101) comprises a high-voltage pulse driving module (101 _ A) which can convert a high-voltage pulse waveform code from the FPGA data processing and peripheral control module (109 _ A) into a positive-polarity discharge single pulse or a negative-polarity discharge single pulse of 1KV ~ 100KV, and the positive-polarity discharge single pulse or the negative-polarity discharge single pulse is applied to the living or non-living biological sample (110) placed in a static uniform magnetic field and an XYZ gradient magnetic field through the non-invasive discharge unit (102) to generate the unpaired electrons in the living or non-living biological sample;

the radio frequency switch or coupling component (105) comprises a radio frequency transmit receive switch module (105 _ A);

the RF source (103) comprises a radio frequency pulse excitation module (103 _ A) which can convert the radio frequency waveform code from the FPGA data processing and peripheral control module (109 _ A) into a radio frequency pulse electromagnetic wave with the frequency of 3MHz ~ 300MHz and the power of 1nW ~ 100W, and the radio frequency pulse electromagnetic wave is applied to the living or non-living biological sample (110) placed in the static uniform magnetic field and the XYZ gradient magnetic field through the radio frequency transceiving switch module (105 _ A) and the radio frequency transceiving resonance coil (104 _ A);

the radio frequency receiving and data sampling assembly (106) comprises a radio frequency receiving and data sampling module (106 _ A), and ESR Spin-lattice relaxation time (T1), Spin-Spin relaxation time (T2), Free Induction Decay signal (Free Induction Decay), Spin Echo signal (Spin Echo), Gradient Echo signal (Gradient Echo) of the unpaired electrons in the living or non-living biological sample (110) placed in the static uniform magnetic field and XYZ Gradient magnetic field and pulse sequence signals derived from the above signals can be acquired by the radio frequency receiving and data sampling module (105 _ A) and the radio frequency receiving and data sampling resonance coil (104 _ A) and sent to the FPGA data processing and peripheral control module (109 _ A);

the FPGA data processing and peripheral control module (109 _ A) can compile corresponding work cycles according to a basic physical process of an ESR phenomenon, each cycle comprises a high-voltage pulse sequence and an ESR system work period (a radio frequency excitation sequence, a magnetic field gradient coding sequence and a radio frequency receiving data sampling sequence), sends a high-voltage pulse waveform code, a radio frequency excitation waveform code, a radio frequency receiving and transmitting switch control code, a static uniform magnetic field strength code and a gradient magnetic field code to corresponding modules, performs fast Fourier transform, spin echo and gradient echo K space decoding on radio frequency receiving data, and transmits the data to the human-computer interface computer (109 _ B) through a data communication interface;

the human-computer interface computer (109 _ B) converts the data transmitted by the FPGA data processing and peripheral control module (109 _ A) into a spectrogram or a three-dimensional space real-time dynamic image which reveals the tissue structure and physiological activity of the living or non-living biological sample (110) and contains information of nerve medium activity, biomolecule metabolism, receptors and chemical components, and further can obtain a three-dimensional image of the brain nerve cell activity on a time scale of the order of mu s because of ESR Spin-lattice relaxation time (T1), Spin-Spin relaxation time (T2), Free Induction Decay signal (Free Induction Decay), Spin Echo signal (Spin Echo) and gradient Echo signal (Gradientecho) and pulse sequence signals derived from the signals are 5 orders of magnitude faster than corresponding nuclear magnetic resonance signals and 3 orders of magnitude faster than nerve synapse conduction speed, therefore, the real-time thinking consciousness of the brain can be directly input into the computer through the interpretation and identification of the computer program, thereby constituting the non-perfusion non-invasive living body ESRI-BCI.

11. The high voltage pulse drive module (101 _ a) of claim 10, further characterized in that a user programmable arbitrary waveform single pulse (user programmable arbitrary waveform single pulse) can be generated, comprising common square pulses (rectangular pulses), gaussian pulses (gaussian pulses), cosine square pulses (cosine square), sine pulse (sine pulse), etc., and the pulse width, polarity, amplitude and repetition frequency of each pulse are user programmable to adapt to the time-frequency response characteristics of different types of high voltage pulse drive circuits and different ESR system duty cycles.

12. The high voltage pulse driving module (101 _ a) according to claim 10, further characterized in that a positive polarity discharge single pulse adapted for positive polarity dc discharge is provided.

13. The high voltage pulse driver module (101 _ a) of claim 10, further characterized in that a negative polarity discharge single pulse is provided, suitable for a negative polarity dc discharge.

14. The hv pulse driver module (101 _ a) according to claim 10, further characterized by being adapted to alternately provide said positive polarity discharge monopulse or negative polarity discharge monopulse for ac discharge in a user programmed sequence of values.

15. The high voltage pulse drive module (101 _ a) of claim 10, further characterized in that the width of said positive polarity discharge monopulse or negative polarity discharge monopulse is adjustable between 0.01 μ s ~ 1000 μ s in accordance with a user programmed value.

16. The high voltage pulse driving module (101 _ a) of claim 10, further characterized in that the time interval between said positive polarity discharge monopulse or negative polarity discharge monopulse is adjusted to between 0.01ms ~ 5000ms and 5000ms according to a user programmed value.

17. The high voltage pulse driving module (101 _ a) of claim 10, further characterized in that the time interval between said positive polarity discharge single pulse or said negative polarity discharge single pulse and the start of said ESR duty cycle is adjusted to be between 0.01ms ~ 5000ms and 5000ms according to a user programmed value.

18. The non-invasive discharge unit (102) according to claim 10, characterized by being a corona discharge unit (102 _ a) or a dielectric barrier discharge unit (102 _ B).

19. The corona discharge unit (102 _ a) according to claim 18, further characterized in that it is formed by connecting a high voltage electrode (301) to the output end of the high voltage pulse driving module (101 _ a) through an external insulated wire by a series resistor (302), the resistor is coated on the external surface by an insulating material (303), the resistance value of the resistor is selected between 0.5M Ω ~ 15M Ω according to the impedance characteristic of the living or non-living organism sample (110), the high voltage electrode is a conductor which is matched with the surface shape of the living or non-living organism sample (110), the discharge end of the high voltage electrode is arranged at 0 ~ 100mm distance from the surface of the living or non-living organism sample (110), the high voltage electrode can safely generate contact discharge, or generate low temperature plasma which can be safely contacted by the living or non-living organism sample (110) through the air in the gap, and form corona discharge.

20. The dielectric barrier discharge unit (102 _ B) according to claim 18, further characterized in that it is formed by connecting a dielectric material (401) to the output end of the high voltage pulse driving module (101 _ a) through an external insulated wire by a series high voltage electrode (402), the high voltage electrode is a conductor conforming to the surface shape of the living or non-living organism sample (110), the discharge end is coated on the external surface by the dielectric material, the material and thickness of the dielectric material are selected according to the impedance characteristics of the living or non-living organism sample (110), the external surface is placed at 0 ~ 100mm from the surface of the living or non-living organism sample (110), a contact discharge can be safely generated, or a low temperature plasma which the living or non-living organism sample (110) can safely contact can be generated by air in a gap, and a dielectric barrier discharge is formed.

Technical Field

The present disclosure relates to Electron Spin Resonance (ESR), and more particularly to a non-invasive in vivo Electron Spin Resonance Spectrometer, three-dimensional imager, and Brain-Computer Interface (ESRI-BCI) system.

Background

The Electron Spin Resonance (ESR) phenomenon, also known as Electron Paramagnetic Resonance (EPR), was first observed in 1944 by e.zavoisky. Earlier, Isidor Rabi first described and measured Nuclear Magnetic Resonance (NMR) of molecular beams in 1938 in a further Stern-Gerlach experiment, and Edward Mills Purcell and Felix Bloch observed the same phenomena in solids and liquids, respectively, in 1946.

Nuclear Magnetic Resonance (NMR) is a phenomenon in which nuclei absorb and re-emit electromagnetic waves in a magnetic field, and Magnetic Resonance Imaging (MRI), originally called Nuclear Magnetic Resonance Imaging (NMRI), is a form of NMR that has proven to be a highly versatile imaging technique that has overwhelmed the advantages of ESR in the field of medical diagnostics. In contrast, the development of ESR in vivo is very slow, the basic principle of ESR is similar to that of NMR, but it is excited by unpaired electrons rather than nuclei. Since most of the substances including organisms lack of naturally occurring paramagnetic substances (i.e., substances containing unpaired electrons), the prior art requires that an exogenous paramagnetic substance (including spin label, spin probe, nano paramagnetic probe, paramagnetic contrast agent, etc.) be perfused or implanted in vivo to observe the ESR signal, for example, U.S. Pat. No. 5,548 (System and method for performing in vivo imaging and oximetry and FT microscopical by pulsed radio frequency electronic response, Obercor 21, 1997), US5865746 (Invivo imaging and oximatory by pulsed radio frequency biological response, February 2, 1999) disclose ESR-based in vivo imaging and oximetry systems and methods, respectively, all of which mention the need for "… in vivo imaging contrast agent in vivo a living sample to be imaged" (… introduces the paramagnetic contrast agent in an imaged living sample) ";

U.S. Pat. No. 5,973,973 (nanoparticule probe for in vivo monitoring of tissue oxygenation, November 29,2011) discloses a new class of nanoparticule probes useful for monitoring in vivo oxygenation using ESR technology, the first paragraph of which claims "… a hererin ear of the progressor, mechenchyl, myoplast, and islet cell a least one probe-introduced thermal, a kind of probe-compounded a output or a biological thermal of the for use: # STR00019# hererin R is selected from the group consisitioning of … (… wherein each progenitor cell, mesenchymal cell, myoblast and islet cell probe comprises at least one probe, the composition of which is …)";

U.S. Pat. No. 2,447 (Electron spin response for medical imaging, January 2,2018) discloses an ESR medical imaging system, the first paragraph of which claims describes "ESR signal from the biological sample a magnetic species, … a magnetic species and the nanoparticles is a magnetic ion nanoparticles (SPION) (ESR signal is derived from paramagnetic substances contained in biological samples, … wherein the paramagnetic substances are SPION nanoparticles)";

chinese patent application publication CN106659417A (electron paramagnetic resonance method and system, application publication No. 2017.05.10) provides Electron Paramagnetic Resonance (EPR) systems and methods for transcutaneous oxygen monitoring (TCOM) and subcutaneous oxygen monitoring (SCOM), which claims the expression "… measures the EPR resonance of the EPR probe, … the EPR probe comprises an oxygen sensitive EPR material embedded in an oxygen permeable polymer, … the EPR probe is adherable to a surface of a tissue of a subject, … the EPR probe is implanted in a tissue of a subject";

the above example reflects the fact that: for living biological samples, the signal observation of the current ESR system completely depends on the perfusion or implantation of exogenous paramagnetic substances, which is unacceptable in the field of general medical diagnosis, and is the main reason why the ESR technique is not commonly used.

On the other hand, MRI has many disadvantages, including particularly expensive manufacturing and operating costs, long scan times for obtaining a desired spatial resolution, etc., and usually 10 ~ 30 minutes for MRI with a magnetic field strength of 0.1T ~ 3T to acquire images, magnets are the most expensive components of MRI scanners, low-field MRI scanners below 0.75T are mostly permanent magnets, some models may weigh even more than 100 tons, are very bulky and heavy, and have limited accuracy and temperature stability, permanent magnets have special safety problems in that ferromagnetic objects are difficult to remove once they are in direct contact with them because their magnetic field cannot be "turned off.

The preferred medium and high fields above 0.75T are 1.5T, 3T superconducting magnets, an electromagnetic field formed by superconductors has extremely high field strength and stability, and is also expensive, and the cryogenic liquid helium system is expensive and difficult to operate. In practice superconducting magnets cannot be "turned off" either because Quench (Quench) and rapid Boiling of liquid helium (boil-off) caused by rapid turn-off present a risk of explosion and must be immediately evacuated. Restarting the superconducting magnet requires several thousand liters of valuable liquid helium to be perfused, the superconducting current to be slowly raised and calibrated, and finally, millions of dollars are spent. Nevertheless, liquid helium cooled superconducting magnets are still the most common type of MRI scanner today.

For brain neurophysiologic activity detection, functional magnetic resonance imaging (fMRI), one of the few non-invasive, non-nuclear radiation exposure-free means, its derived blood oxygen level-dependent contrast technique (BOLD fMRI), which does not directly measure brain functional activity, is not sensitive to the reduction of local deoxyhemoglobin (due to increased neuronal activity, increased local blood flow) by MRI, which is associated with neuronal activity, and thus indirectly reflects brain neuronal activity, the time resolution of fMRI is more likely to depend on physiological dynamics than the rate at which images are acquired.

The Magnetoencephalogram (MEG) technique is a direct measurement of the extremely weak biological magnetic field signal emitted by the nerve current in the brain, the time resolution can reach 1ms, the spatial resolution error is within 0.5mm ~ 1mm, the brain magnetic field is only hundreds of fT (10)^-15T), is extremely weak, and requires a good Magnetic Shielded Room (MSR), with walls sloping awayThe permalloy is used as a high-magnetic-conductivity shielding material, pure aluminum with the thickness of 8 mm is wrapped outside the permalloy to be used as an eddy current shielding layer, the pure aluminum skin is reinforced by a 15 cm aluminum strip, a second permalloy shielding layer is covered outside the pure aluminum strip, and the permalloy shielding layer is different from an electric shielding layer in that the magnetic shielding layer does not need to be grounded. The shielding chamber is completely closed during examination, after the stimulation of sound, light, electricity, etc. is produced by the stimulator outside the chamber, the stimulation is sent into the shielding chamber through the small hole on the chamber wall, and in order to monitor the patient, the chamber is equipped with the lighting and camera equipment which is processed by special degaussing, in the shielding chamber, the head of the examined person is placed in the specially sensitive liquid helium cooling superconducting quantum interference element (SQUID) array. MEG integrates such a large amount of high cost hardware that it is several times more expensive than most superconducting MRI.

Positron Emission Tomography (PET) is currently the only imaging technique that can show biomolecular metabolism, receptor and neuromediator activity in vivo, and its principle is to identify a substance, generally necessary for biological metabolism, such as: glucose, proteins, nucleic acids, fatty acids, labelled with short-lived radionuclides (e.g.¹⁸F，¹¹C, etc.), and after the substance is injected into a human body, the substance is accumulated in the metabolism to reflect the condition of the metabolic activity of the life, so that the diagnosis purpose is achieved, and the time resolution is in the second order.

In summary, MRI, BOLD fMRI, MEG, PET represent the highest level of current medical imaging technology, and ESR has also been successfully applied to the study of paramagnetic substances, but these are always difficult to overcome due to their bulkiness, extreme expense, slow response, reagent perfusion, and nuclear radiation exposure.

Disclosure of Invention

In view of the above drawbacks of the prior art, the present disclosure provides a non-invasive in vivo Electron Spin Resonance (ESR) system and method, and further discloses preferred embodiments thereof: a non-invasive in vivo Electron Spin Resonance Spectrometer, a three-dimensional imager, and a Brain-Computer Interface (Electron Spin Resonance Spectrometer & Imaging-Brain Computer Interface, ESRI-BCI) system.

A non-invasive in-vivo ESR method for safely generating unpaired electrons in a living or non-living biological sample through non-invasive high-voltage discharge, detecting the tissue structure and physiological activity of the living or non-living biological sample by using an ESR technology under the condition of not infusing or implanting exogenous paramagnetic substances (exogenous paramagnet netics), and further acquiring the information of nerve medium activity, biomolecule metabolism, receptors and chemical components, which comprises the following steps:

a high voltage power supply 101, a non-invasive discharge unit 102, a radio frequency Radio (RF) source 103, a radio frequency resonator assembly 104, a radio frequency switch or coupling assembly 105, a radio frequency receiving and data sampling assembly 106, a static uniform magnetic field assembly 107, an optional three-dimensional gradient magnetic field assembly 108, wherein the radio frequency resonator assembly 104 contains the living or non-living biological sample 110 and is placed within the static uniform magnetic field and optional gradient magnetic field generated by the static uniform magnetic field assembly 107 and optional three-dimensional gradient magnetic field assembly 108, and is connected to the RF source 103 through the radio frequency switch or coupling assembly 105 to generate resonance at a set radio frequency; and

a Spectrometer, three-dimensional imager and Brain-Computer Interface (ESRI-BCI) 109 that receives and processes data from the radio frequency reception and data sampling component 106 by operative communication with the high voltage power supply 101, RF source 103, radio frequency switch or coupling component 105, radio frequency resonator component 104, static uniform magnetic field component 107 and optional three-dimensional gradient magnetic field component 108 to measure and visualize ESR Resonance data and further to interpret Brain neural activity signals from the ESR Resonance data into a data stream that can be accepted by a Computer system;

the exogenous paramagnetic substances (exogenous paramagnetic species) include spin labels (spin probes), spin probes (spin probes), nano paramagnetic probes (nano paramagnetic probes), and paramagnetic contrast agents (paramagnetic contrast agents).

The high voltage power supply 101 and the non-invasive discharge unit 102 can apply a positive polarity high voltage or a negative polarity high voltage, which is a voltage capable of ionizing the air gap, to the living or non-living biological sample 110 through the air gap and form a loop through the air gap, so that there is no need to place a conductor on the surface of the living or non-living biological sample 110 to realize the non-invasive discharge;

the high voltage power supply 101 may deprive electrons from the valence shells of molecules and/or anions within the living or non-living biological sample 110 by applying the positive polarity high voltage through the non-invasive discharge unit 102, thereby generating the unpaired electrons;

the high voltage power supply 101 can transfer a certain amount of isolated electrons in an identical fermi state, i.e. free electrons, to the living or non-living biological sample 110 by applying the negative polarity high voltage through the non-invasive discharge unit 102, and the free electrons are immediately captured by the positive terminal and/or positive valence electron layer of the polar molecules in the living or non-living biological sample 110, so as to generate the unpaired electrons;

the conduction velocity of the high-voltage discharge is the speed of light, and the unpaired electrons can be instantaneously loaded on relevant molecules and/or ions at any position in the living or non-living biological sample 110, so that the ESR technology can be applied to obtain the dynamic spatial distribution information of the unpaired electrons in the living or non-living biological sample 110, and the dynamic spatial distribution information can reflect the tissue structure and physiological activity of the living or non-living biological sample 110;

further, such factors as chemical bonds of related molecules and/or ions of the unpaired electron carrier, nuclear magnetic dipoles, electron magnetic dipoles and adjacent groups cause the ultra-fine splitting effect of the ESR spectrum, so that the ESR technology can be applied to further obtain information of nerve medium activity, biomolecule metabolism, receptors and chemical components;

the RF source 103 can operate in a Continuous Wave (Continuous Wave) mode or a Time Domain (Time Domain) pulse mode, and the operating frequency thereof can be selected within the range of 300KHz ~ 300 GHz;

the source of the static uniform magnetic field assembly 107 can be a permanent magnet, a normal temperature electromagnet or a superconducting electromagnet, the magnet can be a cylinder closed type or a biplane open type, and the magnetic field intensity can be selected within the range of 0.00001T ~ 10.7.7T so as to adapt to the ESR frequency of 300KHz ~ 300 GHz;

the living or non-living biological sample 110 can be a body, tissue, organ, or cell of a plant, animal, or human;

the ESR method of the non-invasive living body comprises the following steps:

(1) first, the living or non-living biological subject 110 is placed in the static uniform magnetic field assembly 107 in an electrically isolated environment within the resonator assembly 104, wherein the living or non-living biological subject 110, like other substances in nature, has no detectable naturally occurring unpaired electrons therein;

(2) then, the high voltage power supply 101 is started, the positive polarity or negative polarity high voltage is applied through the non-invasive discharge unit 102, the unpaired electrons are generated in the living or non-living biological sample 110, and various polarity molecules and/or ions in the living or non-living biological sample 110 make the sample have good conductors such as conductivity and nonmetal, so that charges can be stored in an insulating environment and can be regarded as equivalent capacitance, and the unpaired electrons in the living or non-living biological sample 110 can be stably maintained due to the biological capacitance effect;

(3) then, the high voltage output of the high voltage power supply 101 is turned off, and ESR working cycles are started, tissue structures and physiological activities of the living or non-living biological sample 110 are detected, and information of nerve medium activity, biomolecule metabolism, receptors and chemical components is further acquired, wherein each ESR working cycle comprises a radio frequency excitation sequence, an optional magnetic field gradient coding sequence and a radio frequency receiving data sampling sequence;

(4) finally, after the ESR working period is completed, the high-voltage power supply 101 is started again to enter the next cycle; start-stop of high voltage power supply 101 alternates every in ESR duty cycle's clearance, every in the ESR duty cycle, high voltage power supply 101 gets into the state of rest, stops all high voltage drive device's activity to avoid right ESR duty cycle's electromagnetic interference. The ESRI-BCI109 manages the high voltage output and ESR duty cycle by operatively communicating with the high voltage power supply 101, RF source 103, radio frequency switch or coupling assembly 105, radio frequency resonator assembly 104, static uniform magnetic field assembly 107, and optional three-dimensional gradient magnetic field assembly 108, receives and processes data from the radio frequency receiving and data sampling assembly to measure and visualize ESR resonance data, and analytically processes cerebral neural signals.

Compared with the prior art, the method provided by the disclosure can be used for detecting living or non-living biological samples by using the ESR technology in a non-invasive manner under the condition of no perfusion or implantation of exogenous paramagnetic substances, and has great technical advantages:

first, the electron magnetic moment is 658 times greater than proton, so the same resonance frequency, ESR requires 658 times weaker magnetic field than NMR, and if the resonance frequency is set at 200MHz, the MRI scanner requires a 4.7T high field superconducting magnet, while ESRI requires only 0.0071T (i.e., 7.1mT or 71 Gauss) magnet, and using no more than 3kg air-cored Helmholtz Coil (Helmholtz Coil) is sufficient to generate such a field, tens of thousands times lighter than a permanent magnet or a superconducting magnet, for a volume of the human brain;

secondly, under the above conditions, the spin-lattice relaxation time (T1) and the spin-spin relaxation time (T2) of electrons are about 5 mus and 10ns respectively, the spectral line width is from several KHz to several MHz, the T1 and the T2 corresponding to protons are about 1s and 0.1s respectively, the spectral line width is from several Hz to several KHz, therefore, under the same radio frequency excitation frequency, the response speed of ESR is theoretically 20 ten thousand times and 5 orders of magnitude faster than that of NMR, the spectral line resolution is 1 thousand times and 3 orders of magnitude higher, therefore, the tissue structure and physiological activity of the living or non-living biological sample can be captured at high speed, and further the information of nerve medium activity, biological molecule metabolism, receptors and chemical components can be obtained, thereby the three-dimensional image of brain nerve cell activity can be obtained on the time scale of mus level, the real-time consciousness of brain can be directly input into a computer through interpretation and identification by a computer program, thereby constituting non-invasive living body ESRI-BCI;

as can be seen from the above comparative data, the method provided by the present disclosure is 1 thousand times faster than MEG in response speed, biochemical analysis ability exceeds PET without nuclear radiation exposure, weight and cost are more than the beginnings of current MRI, BOLD fMRI, MEG and PET devices, which will enable the portable non-invasive living Electron Spin Resonance Imaging (ESRI) to enter thousands of households like a personal computer that eliminates a hundred tons of large computers in the year, and a brain-computer interface (BCI) derived therefrom will also improve human-computer interaction ability to the thought of world.

Drawings

Preferred embodiments of the present disclosure are described herein with reference to the accompanying drawings, and how to practice the embodiments will become readily apparent to those skilled in the art from the description herein.

FIG. 1 is a schematic diagram of ESR method for non-invasive living body

FIG. 2 is a system diagram of a preferred embodiment of a non-invasive in vivo ESR method;

FIG. 3 is a schematic diagram of a corona discharge unit structure;

FIG. 4 is a schematic diagram of a dielectric barrier discharge cell structure;

FIG. 5 is a schematic of the high voltage pulse sequence and ESR system duty cycle (radio frequency excitation sequence, magnetic field gradient encoding sequence, and radio frequency receive data sampling sequence);

fig. 6 is a schematic diagram of a high voltage pulse waveform, wherein:

a is square pulse (rectangular pulse);

b is cosine square pulse (cosine squared);

c is sinc pulse (sinc pulse);

d is a Gaussian pulse;

e is a user programmable arbitrary waveform single pulse (user programmable arbitrary waveform single pulse);

FIG. 7 is a three-dimensional view of a Helmholtz coil and RF transceiver resonance coil configuration;

fig. 8 is a top view from left to right of Z, Y, X gradient magnetic field coils, respectively;

FIG. 9 is an exploded view of a Helmholtz coil, XYZ gradient magnetic field coils, and a radio frequency transmit-receive resonance coil;

FIG. 10 is an exploded view of a Helmholtz coil, XYZ gradient magnetic field coils, and a radio frequency transmit-receive resonance coil, particularly illustrating how the XYZ gradient magnetic field coils are superimposed;

FIG. 11 is a diagram showing the overall assembly effect of a Helmholtz coil, an XYZ gradient magnetic field coil, a radio frequency transmit-receive resonance coil and a dielectric barrier discharge unit;

FIG. 12 is a diagram showing the overall effect of the Helmholtz coil, the XYZ gradient magnetic field coil, the RF transmitting/receiving resonance coil, and the dielectric barrier discharge unit loaded on the human body.

Detailed Description

Before explaining at least one embodiment of the disclosure in detail, it is to be understood that the methods provided by the disclosure are not necessarily limited in its application to the details of construction, arrangement and the parameters of the components and/or methods set forth in the following description and/or illustrated in the drawings and/or examples, and that the methods provided by the disclosure are capable of other embodiments or of being practiced or carried out in various ways, which are explained in detail below in connection with the drawings and the embodiments.

A non-invasive in vivo Electron Spin Resonance Spectrometer, three-dimensional imager and Brain-Computer Interface (Electron Spin Resonance Spectrometer & Imaging-Brain Computer Interface, ESRI-BCI) system, specifically comprising:

a high voltage power supply 101, a non-invasive discharge unit 102, a radio frequency Radio (RF) source 103, a radio frequency resonator assembly 104, a radio frequency switch or coupling assembly 105, a radio frequency receive and data sampling assembly 106, a static uniform magnetic field assembly 107, an optional three-dimensional gradient magnetic field assembly 108, and an ESRI-BCI109, as shown in fig. 1.

The ESRI-BCI109 comprises an FPGA data processing and peripheral control module 109_ A and a human-computer interface computer 109_ B;

the static uniform magnetic field component 107 comprises a static uniform magnetic field Coil driving module 107_ a and a static uniform magnetic field Coil, and with reference to fig. 2 and 7, the static uniform magnetic field Coil is a pair of air-core Helmholtz coils (Helmholtz coils) 107_ B with a diameter of 360mm, and the static uniform magnetic field component 107 can convert a static uniform magnetic field strength code from the FPGA data processing and peripheral control module 109_ a into a static uniform magnetic field with a diameter of 0.0001T ~ 0.0107.0107T, so as to adapt to ESR frequencies of 3MHz-300 MHz;

the three-dimensional gradient magnetic field assembly 108 comprises an XYZ gradient magnetic field coil driving module 108_ A, XYZ gradient magnetic field coil 108_ B, with reference to fig. 2, 8, 9 and 10, the XYZ gradient magnetic field coil 108_ B is a disk-type biplane gradient coil embedded in an inner diameter plane of the helmholtz coil 107_ B, and is formed by superimposing an X gradient magnetic field coil 108_ B _ Gx, a Y gradient magnetic field coil 108_ B _ Gy and a Z gradient magnetic field coil 108_ B _ Gz along an axial direction of the helmholtz coil 107_ B, and the three-dimensional gradient magnetic field assembly 108 can encode and convert a gradient magnetic field from the FPGA data processing and peripheral control module 109_ a into a gradient magnetic field to obtain two-dimensional or three-dimensional spatial distribution information of the unpaired electrons in the live or non-live biological sample 110;

the rf resonator assembly 104 includes an rf resonant coil 104_ a, which is an air core coil with an inner diameter equal to or less than the center-to-center distance of the helmholtz coil 107_ B, and a center plane thereof is perpendicular to the plane of the helmholtz coil 107_ B and coplanar with the axial line of the helmholtz coil 107_ B, and with reference to fig. 2 and 7, the rf resonant coil 104 is an air core coil with an inner diameter of 180mm, which is wrapped in an insulating material and connected to the helmholtz coil 107_ B through a support member 201;

the high voltage power supply 101 includes a high voltage pulse driving module 101_ a, which can convert the high voltage pulse waveform code from the FPGA data processing and peripheral control module 109_ a into a positive or negative voltage of 1KV ~ 100KV, and is applied to the living or non-living organism sample 110 placed in the static uniform magnetic field and the XYZ gradient magnetic field by the non-invasive discharging unit 102 to generate the unpaired electrons inside thereof, in conjunction with fig. 6, the high voltage pulse driving module 101_ a can generate user programmable arbitrary waveform single pulses (user programmable random pulse) including common square pulses (rectangular pulses), gaussian pulses (gaussian pulses), cosine square pulses (cosine square pulses), sine pulses (sine pulses) and the like, and the pulse width, polarity, amplitude and repetition frequency of each pulse are user programmable to adapt to the time-frequency response characteristics of different types of high voltage pulse driving circuits and different ESR operation periods of the system;

the high-voltage pulse driving module 101_ a may provide a positive polarity discharging single pulse, which is suitable for positive polarity dc discharging;

the high-voltage pulse driving module 101_ a can provide negative polarity discharge single pulse, and is suitable for negative polarity direct current discharge;

the high-voltage pulse driving module 101_ a may alternately provide a positive polarity discharge single pulse and a negative polarity discharge single pulse according to a numerical sequence programmed by a user, and is suitable for ac discharge;

the high voltage pulse driving module 101_ a may adjust the width of the high voltage pulse to be between 0.01 μ s ~ 1000 μ s according to a value programmed by a user;

the high voltage pulse driving module 101_ a may adjust a time interval between high voltage pulses to be 0.01ms ~ 5000ms according to a value programmed by a user;

the high voltage pulse driving module 101_ a may adjust a time interval between the high voltage pulse and the rf excitation start time to be 0.01ms ~ 5000ms according to a value programmed by a user;

the rf switch or coupling component 105 includes an rf transmit receive switch module 105_ a;

the RF source 103 comprises a radio frequency pulse excitation module 103_ a, which can convert the radio frequency waveform code from the FPGA data processing and peripheral control module 109_ a into radio frequency electromagnetic wave with frequency of 3MHz ~ 300MHz and power of 1nW ~ 100W, and is applied to the living or non-living biological sample 110 placed in the static uniform magnetic field and XYZ gradient magnetic field through the radio frequency transceiving switch module 105_ a and radio frequency transceiving resonance coil 104_ a;

the rf receiving and data sampling module 106 comprises an rf receiving and data sampling module 106_ a, which can collect ESR Spin-lattice relaxation time (T1), Spin-Spin relaxation time (T2), Free Induction Decay signal (Free Induction Decay), Spin Echo signal (Spin Echo), Gradient Echo signal (Gradient Echo) of unpaired electrons in the living or non-living biological sample 110 placed in the static uniform magnetic field and XYZ Gradient magnetic field through the rf transceiving switch module 105_ a and the rf transceiving resonance coil 104_ a, and transmit pulse sequence signals derived from these signals to the FPGA data processing and peripheral control module 109_ a;

the FPGA data processing and peripheral control module 109_ a may compile corresponding work cycles according to a basic physical process of an ESR phenomenon, and with reference to fig. 5, each cycle includes a high-voltage pulse sequence and an ESR system work period (a radio frequency excitation sequence, a magnetic field gradient coding sequence, and a radio frequency received data sampling sequence), transmits the high-voltage pulse waveform code, the radio frequency excitation waveform code, a radio frequency transmit-receive switch control code, a static uniform magnetic field strength code, and a gradient magnetic field code to the corresponding module, performs fast fourier transform, spin echo, and gradient echo K spatial decoding on radio frequency received data, and transmits the data to the human-computer interface computer through a data communication interface;

the human-computer interface computer 109_ B converts the data transmitted from the FPGA data processing and peripheral control module 109_ a into a spectrogram or three-dimensional space real-time dynamic image which reveals the tissue structure and physiological activity of the living or non-living biological sample 110, including information of nerve medium activity, biomolecule metabolism, receptors and chemical components, further due to the Spin-lattice relaxation time (T1), Spin-Spin relaxation time (T2), Free Induction Decay signal (Free Induction Decay), Spin Echo signal (Spin Echo) and Gradient Echo of ESR, and pulse sequences derived from the above signals are 5 orders of magnitude faster than the corresponding nuclear magnetic resonance signals, 3 orders of magnitude faster than the nerve synapse conduction speed, and can obtain a three-dimensional image of brain nerve cell activity on a time scale of the order of μ s, therefore, the real-time thinking consciousness of the brain can be directly input into the computer through the interpretation and identification of the computer program, thereby constituting the non-invasive living ESRI-BCI. Additionally, in conjunction with FIG. 2, the schematic diagram of the present embodiment, in which a communication interface is used to connect the human-machine interface computer and the FPGA data processing and peripheral control module, the present disclosure contemplates that the communication interface may be implemented by any medium, including but not limited to a wired link, a wireless link, and an optical link;

the non-invasive discharge unit 102 may be a corona discharge unit 102_ a or a dielectric barrier discharge unit 102_ B;

with reference to fig. 3, the corona discharge unit 102_ a is covered in an outer insulating layer 303, and is formed by connecting a high voltage electrode 301 to an output end of the high voltage pulse driving module 101_ a through a series resistor 302 via a wire, wherein a resistance value of the resistor is selected between 0.5M Ω ~ 15M Ω according to an impedance characteristic of the living or non-living biological sample 110, the high voltage electrode is a conductor conforming to a surface shape of the living or non-living biological sample 110, and a discharge end thereof is disposed at a distance of 0 ~ 100mm from a surface of the living or non-living biological sample 110, so that a contact discharge can be safely generated, or a low temperature plasma which can be safely contacted by the living or non-living biological sample 110 can be generated through air in a gap to form a corona discharge;

with reference to fig. 4, the dielectric barrier discharge unit 102_ B is formed by connecting a dielectric material 401 to the output end of the high voltage pulse driving module 101_ a through an external insulated wire by serially connecting high voltage electrodes 402, wherein the high voltage electrodes are conductors conforming to the surface shape of the living or non-living biological sample 110, the discharge ends of the high voltage electrodes are coated on the outer surface by the dielectric material, the material and the thickness of the dielectric material are selected according to the impedance characteristics of the living or non-living biological sample 110, the outer surface of the dielectric material is placed at a distance of 0 ~ 100mm from the surface of the living or non-living biological sample 110, so that contact discharge can be safely generated, or low temperature plasma which can be safely contacted by the living or non-living biological sample 110 can be generated through air in the gap, so that dielectric barrier;

with reference to fig. 11, the dielectric barrier discharge unit 102_ B may be adhered to the inner side of the rf transceiving resonance coil 104_ a;

with reference to fig. 12, the dielectric barrier discharge unit 102_ B may generate a dielectric barrier discharge at the forehead or the occipital region of the head of a human body.

While the methods provided by the present disclosure have been described in conjunction with specific embodiments thereof, many obvious substitutions, modifications and changes will be apparent to those skilled in the art, and it is intended that the present disclosure encompass all such substitutions, modifications and changes as fall within the spirit and broad scope of the appended claims. Further, such as high voltage pulse circuits, rf transceiver circuits, gradient magnetic field driving circuits, FPGA circuits, computer programming, and ESR system principles are known in the relevant art and have well established components or products, and thus the present disclosure focuses on methods for safely generating unpaired electrons in living or non-living biological samples by non-invasive high voltage discharge to detect tissue structure and physiological activity in living or non-living biological samples using ESR techniques without perfusing exogenous paramagnetic substances, and will not be discussed in detail for those not referring to the appended claims.