A device system for rapidly thawing frozen biological samples

Abstract

The present invention discloses a set of instruments for rapidly thawing frozen biological samples, including a sample container for accommodating frozen biological samples, a combination of different electromagnetic and optical heat sources, a temperature control monitoring sensor, and a comprehensive control heating system. For different biological samples, by monitoring the temperature of the frozen biological samples in all directions, designing corresponding sample containers, and providing different electromagnetic heating methods accordingly, the frozen biological samples can be heated very quickly and the heating rate can be accurately controlled, and the temperature difference between different parts can be reduced, thereby improving the survival rate of the frozen biological samples after heating.

Description

Technical Field

[0001] The present invention relates to the technical field of cryopreservation of biological materials, and in particular to a highly efficient heating and rewarming method utilizing different energy sources in combination. Background Art

[0002] Long-term storage of biological materials can keep the current surplus resources available when needed in the future, or increase the time limit for shipping biological material resources. Long-term storage methods for biological materials usually require the use of cryogenic technology. Optimization of cryogenic storage technology will overcome problems such as solution damage and ice crystal formation.

[0003] Currently, there is a lack of ultra-fast and uniform heating methods in the field of cryogenic biological preservation. Traditional water bath heating places frozen samples in 37°C warm water to heat them up, and heat is transferred from the surface of the frozen samples to the inside. However, the energy provided by water bath heating is small and can only produce a slower heating rate. Slow heating will cause recrystallization (ice crystals will form again) during the rewarming process. The boundary heat transfer method will cause uneven heating inside and outside, and the resulting thermal stress will cause partial fracture of the frozen samples and cause damage.

[0004] Although the electromagnetic heating method subsequently adopted has improved heating rate and heating uniformity compared to water bath heating, there is still a certain temperature difference due to the field strength distribution of electromagnetic waves in biological samples, and there is a lack of control over the electromagnetic field, resulting in high power usage and difficulty in promotion. Summary of the invention

[0005] In order to overcome the problems of slow heating rate and large temperature gradient in the field of cryopreservation, the present invention provides a thawing system for efficiently and evenly and controllably heating frozen biological samples or foods.

[0006] The technical solution adopted by the present invention is to establish a combined rewarming system platform with precise frequency synthesis and feedback control. The electromagnetic resonant heating system with frequency tracking quickly transmits and converts energy to achieve rapid heating of frozen samples. In addition, laser is added to the surface part for combined heating to improve the uniformity of the temperature field. During the application process, the combined rewarming system uses infrared, optical fiber, thermocouples and other means to monitor the overall temperature inside and outside the sample, and the frequency of the electromagnetic resonant system is always adjusted with temperature feedback and power feedback. The combined rewarming system platform includes:

[0007] A combined electromagnetic and laser energy source; a container and an electromagnetic resonance cavity for loading frozen samples; a probe antenna for exciting the electromagnetic field in the cavity; a real-time monitoring system for monitoring the temperature of the frozen samples in the container; and an electromagnetic heating feedback regulation control system.

[0008] The initial signal of the electromagnetic energy source is synthesized by a frequency synthesizer or a magnetron, and is connected to a power amplifier to increase the signal power.

[0009] Preferably, the frequency range of the signal source is 100 MHz to 3 GHz, and the power amplifier increases the signal power to 100 to 800 W.

[0010] The laser energy source is located outside the electromagnetic resonance cavity and is provided with laser by one or more laser transmitters.

[0011] Preferably, the wavelength range of each laser emitter is 808nm to 1080nm, the emission power is 0.5~50W, and the spot diameter of the laser emitter is adjustable in the range of 1~20mm.

[0012] The shape of the container for loading frozen samples is a hollow cylinder, a cuboid or a sphere. The container material can be a high molecular polymer such as polyethylene, polypropylene, etc., which has a low absorption rate of electromagnetic energy. Ferromagnetic, paramagnetic or superparamagnetic nanomaterials can also be added to the container material.

[0013] Preferably, the size of the magnetic nanomaterial added to the frozen sample container is 5 to 50 nm.

[0014] The electromagnetic resonance cavity material is made of metals such as copper and iron oxide or metal oxides, and has a high quality factor (quality factor Q value>1000). The electromagnetic resonance cavity can absorb most of the electromagnetic energy transmitted through the probe antenna and excite a resonant electromagnetic field inside.

[0015] Preferably, the electromagnetic resonance cavity is a single-mode resonant electromagnetic cavity, and only one standing wave electromagnetic field can be excited in the cavity.

[0016] Preferably, there is an opening just above the electromagnetic resonance cavity, and is connected to a tubular metal waveguide. The frequency range of electromagnetic waves transmitted by the metal waveguide is determined by the cross-sectional size. The cross-sectional size of the metal waveguide is designed to be narrow and cannot transmit electromagnetic waves within the frequency range of the signal source.

[0017] Preferably, the temperature measurement may include an optical fiber sensor or a thermocouple inserted into the frozen sample; and an infrared thermometer measuring the surface of the frozen sample.

[0018] Preferably, the feedback control of the combined temperature recovery system platform can adjust the frequency and power of electromagnetic waves and the power of lasers according to the temperature distribution through a computer or a control circuit chip.

[0019] Preferably, the electromagnetic heating feedback adjustment system can calculate according to the power absorbed and fed back in the electromagnetic resonance cavity, and adjust the frequency of the electromagnetic signal source.

[0020] Compared with the prior art, the present invention uses a combined electromagnetic and laser energy source to perform internal and external uniform heating of the frozen sample by multiple energy transmissions. The electromagnetic energy is transmitted to the electromagnetic resonance cavity through the probe antenna, the energy is concentrated at the location of the frozen sample, and the frozen sample is heated and reheated as a whole. The laser energy source directly irradiates the surface of the frozen sample to further reduce the internal and external temperature difference of the frozen sample. The combined uniform heating can reduce the thermal stress generated in the frozen sample. During the heating process, the resonant frequency of the electromagnetic resonance cavity will continue to change. The feedback control system of the combined rewarming platform will always monitor the electromagnetic energy reflected from the electromagnetic resonance cavity, and adjust and control the frequency of the electromagnetic energy source, track the resonant frequency of the electromagnetic resonance cavity, ensure ultra-high-speed heating of the frozen sample, and avoid the problems of devitrification and recrystallization during the rewarming process. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 A schematic diagram of the structure of a combined rewarming system provided by an embodiment of the present invention;

[0022] Figure 2 It is a schematic diagram of the structure of a probe antenna in one embodiment of the present invention;

[0023] Figure 3 It is a structural schematic diagram of a temperature measurement system in one embodiment of the present invention;

[0024] Figure 4 A schematic diagram of the structure of a power feedback system in one embodiment of the present invention;

[0025] Markings in the figure:

[0026] 1: electromagnetic signal source; 2: power amplifier; 3: power feedback system; 4: probe antenna; 5: electromagnetic resonance cavity; 6: hollow waveguide; 7: cryopreservation container; 8: cryopreserved sample; 9: temperature measurement system; 10: laser energy source. DETAILED DESCRIPTION

[0027] The present invention is further described below with reference to the accompanying drawings. This embodiment provides a frozen biological sample rewarming device, which uses a feedback control frequency tracking method to establish a resonant electromagnetic field and combines a laser energy source to efficiently and quickly rewarm the frozen sample, while enhancing the uniformity of the temperature field, and can effectively rewarm a large volume of biological or food frozen samples and maintain biological activity.

[0028] like Figure 1 As shown, Figure 1 A schematic diagram of the structure of the combined rewarming system provided in this embodiment includes an electromagnetic signal source 1, a power amplifier 2, a power feedback system 3, a probe antenna 4, an electromagnetic resonance cavity 5, a hollow waveguide 6, a cryopreservation container 7, a cryopreserved sample 8, a temperature measurement system 9, and a laser energy source 10.

[0029] In the present invention, the frozen sample 8 is placed in a cryopreservation container 7, which can be a cryopreservation tube commonly used in the field of cryobiology or other specially designed containers taken out of liquid nitrogen or a deep low temperature refrigerator and placed in the center of the electromagnetic resonance cavity 5. The electromagnetic signal generated by the electromagnetic signal source 1 is increased in power by the power amplifier 2 and then transmitted to the probe antenna 4 through a wire, and the electromagnetic field in the electromagnetic resonance cavity 5 is excited by the probe antenna 4 for rewarming. The frequency range of the electromagnetic signal is 100MHz~3GHz, and the power is 100~800W. Figure 2 The schematic diagram of the probe antenna structure of this embodiment is shown. The base 43 of the probe antenna 4 is made of stainless steel or iron, and the center is an interface 44 for connecting the transmission line. The interface 44 is internally connected to a cylindrical needle-shaped conductor antenna 41 made of copper or gold or other high-conductivity metal or metal alloy material. The needle-shaped conductor antenna has a length of 10 to 60 mm and a diameter of 0.2 to 5 mm. The needle-shaped conductor antenna 41 is wrapped with an insulating protective layer 42. The material of 42 is a polymer material such as polytetrafluoroethylene. The insulating protective layer is tubular, with a wall thickness of 0.2 to 2 mm and a length of 1 to 20 mm.

[0030] While turning on the electromagnetic signal source 1, the laser energy source 10 also heats the frozen sample 8, and the generated laser directly irradiates the surface of the frozen sample. The wavelength range of the laser emitter is 808nm to 1080nm, the emission power is 0.5~50W, and the spot diameter of the laser emitter is adjustable in the range of 1~20mm. The energy of the electromagnetic field is concentrated in the center of the microwave resonance cavity, and the energy gradually decays outward. The energy of the laser irradiation is combined with the electromagnetic field energy to reduce the temperature difference and avoid the problem of internal fracture of the frozen sample caused by thermal stress.

[0031] In this embodiment, during the heating process, the temperature measurement system 9 measures the temperature field of the frozen sample 8. Figure 3 As shown, an optical fiber or thermocouple is inserted into the frozen sample for measurement, and an infrared thermometer measures the temperature distribution on the surface of the frozen sample. The temperature measurement system can be connected to a computer or microprocessor control to adjust the frequency and power distribution of the electromagnetic energy source and the laser energy source according to the measured temperature field.

[0032] In this embodiment, during the heating process, the power feedback system 3 is as follows: Figure 4 As shown, the directional coupler in the power feedback system has a port connected to a power meter or a spectrum analyzer, which can measure the power reflected from the microwave resonance cavity 5. The computer or microprocessor adjusts the frequency of the electromagnetic signal source according to the reflected power measured by the power feedback system to reduce the reflected power to a minimum.

Claims

1. A device system for rapidly thawing frozen biological samples, characterized in that: It includes a combined energy heat source system of electromagnetic and laser light sources, a container for loading frozen samples and an electromagnetic resonance cavity, a real-time monitoring system for monitoring the temperature of the frozen samples in the container, and an electromagnetic heating feedback regulation control system; The electromagnetic energy source in the combined energy heat source system is microwaves, which are generated by a crystal oscillator frequency synthesizer or a magnetron. The power of the microwave energy source is increased by a power amplifier, and the electromagnetic energy source and the power amplifier are connected by a coaxial transmission line; The resonant frequency of the electromagnetic resonance cavity matches that of the electromagnetic energy source or is within 1 MHz of that of the electromagnetic energy source; The electromagnetic resonance cavity is a hollow cuboid or cylinder, and the cavity wall thickness is 1-10mm; The electromagnetic wave generated by the electromagnetic energy source is connected to an antenna probe through a coaxial wire, and the antenna probe excites the resonant electromagnetic field in the electromagnetic resonance cavity. The electromagnetic field in the cavity is a standing wave when it resonates.

2. The device system for rapidly thawing and freezing biological samples according to claim 1, characterized in that: The electromagnetic signal frequency provided by the microwave signal source and the matching rectangular or circular waveguide resonant frequency range is 100MHz-3GHz. After the power amplifier increases the power, the power provided by the microwave signal source ranges from 100W to 800W. An impedance matcher is connected between the microwave signal source and the electromagnetic antenna probe to adjust the impedance matching between the signal source, the antenna and the waveguide.

3. The device system for rapidly thawing and freezing biological samples according to claim 1, characterized in that: The laser energy source in the combined energy heat source system includes one or more laser emitters, and the distance between the laser emitters and the cryopreserved samples can be adjusted; The wavelength range of each laser transmitter is 808nm to 1080nm, the emission power is between 0.5W and 50W, and the laser transmitter spot diameter can be adjusted between 1-20mm.

4. The device system for rapidly thawing and freezing biological samples according to claim 1, characterized in that: The electromagnetic antenna is made of copper, and the length of the electromagnetic antenna is 10-100mm.

5. The device system for rapidly thawing and freezing biological samples according to claim 1, characterized in that: The microwave resonant cavity has an interface for connecting to the electromagnetic antenna probe. The cavity is in the shape of a hollow cuboid or cylinder. The resonant cavity is made of copper and iron oxide materials. The cavity resonance frequency is consistent with the frequency range of the electromagnetic signal source, which is 100MHz to 3GHz.

6. The device system for rapidly thawing and freezing biological samples according to claim 1, characterized in that: The frozen sample container is in the shape of a hollow cylinder, and the frozen sample container is located in the center of the electromagnetic resonance cavity; The container used to hold the frozen samples is made of a material that absorbs the energy of the electromagnetic wave source, and is added with a high molecular polymer and zirconium oxide ceramics with magnetic materials.

7. The device system for rapidly thawing and freezing biological samples according to claim 1, characterized in that: The internal temperature of the frozen samples was measured by optical fiber and thermocouple, and the surface temperature of the frozen samples was measured by infrared thermometer.

8. The device system for rapidly thawing and freezing biological samples according to claim 1, characterized in that: The electromagnetic heating feedback regulation control system includes a directional coupler, a power meter or a spectrum analyzer; the directional coupler is connected to the electromagnetic resonance cavity, the power meter or the spectrum analyzer through a coaxial transmission line; During the heating process, the power reflected by the electromagnetic resonance cavity is measured by a power meter or a spectrum analyzer, and the frequency of the electromagnetic signal source is adjusted according to the reflected power.

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