Optogenetic stimulation device and method

Abstract

The application provides a kind of optogenetic stimulation device and method, optogenetic stimulation device includes wearable carrier, light stimulation module and external control part;Light stimulation module is fixedly arranged on wearable carrier, the light emission surface of light stimulation module faces the body surface or superficial target tissue of experimental animal;External control part is detachably electrically connected with light stimulation module by flexible connecting line;External control part is used to provide driving signal to light stimulation module, to control light stimulation module output preset parameter's stimulating light.In the application, wearable carrier stably fixes light stimulation module on the target area of experimental animal body surface, guarantees the consistency of stimulation position and the feasibility of repeated wearing;External control part is detachably electrically connected with light stimulation module, which is convenient for wearing debugging and module replacement;External control part provides driving signal to light stimulation module, so that it outputs stimulating light according to preset parameters, realizes the standardization control of light stimulation parameters, and improves the repeatability of experiment.

Description

Technical Field

[0001] This application belongs to the field of optogenetics in laboratory animals, and more specifically, relates to an optogenetic stimulation device and method. Background Technology

[0002] Optogenetics is a neurobiological research technique that involves expressing light-sensitive proteins in specific tissues and cells and then using light of a specific wavelength to stimulate and regulate the activity of related neurons or tissues and cells. It has been widely used in animal experimental research in neuroscience, physiology, pharmacy and other fields.

[0003] In optogenetic studies of surface or superficial target areas (such as the heart, gastrointestinal tract, peripheral nerves, superficial muscles, or subcutaneous tissue) in laboratory animals like mice, current technologies mainly employ methods such as implanted fiber optic stimulation, implanted micro-LED stimulation, or external illumination stimulation. Implanted fiber optic stimulation typically involves implanting a fiber optic cable into the target area via stereotactic surgery, and then transmitting light stimulation to the target tissue through an external laser or light source via the fiber optic cable. Implanted micro-LED stimulation places a miniature light source near the target area, powered and controlled via wired or wireless means. External illumination stimulation involves placing a light source outside the animal cage or on an experimental platform to irradiate the animal's surface or target area. Of these methods, implanted methods usually require surgical implantation, which is complex and prone to causing tissue damage or inflammatory reactions. Furthermore, it increases the animal's load, making long-term experiments in a free-moving state inconvenient. With external illumination methods, the distance and angle between the light source and the target area on the animal's surface easily change with the animal's movement, making it difficult to ensure the stability of the stimulation position and light intensity.

[0004] For optogenetic stimulation of superficial target areas, some studies have attempted to directly attach or temporarily weld light-emitting diodes (LEDs) to the animal's skin for localized illumination, reducing the complexity and invasiveness of deep implantation procedures. However, this approach still has the following shortcomings: First, LEDs are usually fixed to the animal's skin surface by adhesive or temporary welding, lacking a dedicated fixation carrier. This makes them prone to displacement or even detachment during animal movement, leading to unstable stimulation positions, difficulty in repeated wear, and inability to meet the needs of long-term experiments in free-movement states. Second, the LEDs are directly welded to the external driving circuit via wires, lacking a detachable connection structure. This makes it inconvenient to operate during animal wearing, device debugging, and troubleshooting, and repeated welding can easily damage the device. Third, the light output intensity often uses simple resistor current limiting or direct power supply methods, lacking standardized driving signal control. The light output is prone to fluctuations with changes in power supply voltage and temperature, making it difficult to guarantee the consistency of stimulation parameters between different experimental batches. Summary of the Invention

[0005] The purpose of this application is to provide an optogenetic stimulation device and method to solve the technical problems of unstable light source fixation, inconvenient disassembly and assembly, and difficulty in standardizing stimulation parameters in existing surface optogenetic stimulation devices.

[0006] To achieve the above objectives, the technical solution adopted in this application is as follows: A photogenetic stimulation device is provided, comprising a wearable carrier, a photostimulation module, and an external control unit; the wearable carrier is worn on the body surface of an experimental animal; the photostimulation module is fixedly disposed on the wearable carrier, with its light-emitting surface facing the body surface or superficial target tissue of the experimental animal, for emitting stimulation light; the external control unit is detachably electrically connected to the photostimulation module via a flexible connecting wire; the external control unit is used to provide a driving signal to the photostimulation module to control the photostimulation module to output stimulation light with preset parameters.

[0007] Furthermore, the photostimulation module includes a light-emitting element, a substrate, and a heat dissipation fixing structure; the light-emitting element is fixed to the front side of the substrate, and the flexible connecting wire is soldered to the positive and negative electrode pads on the substrate; the heat dissipation fixing structure is disposed on the back side of the substrate to assist the light-emitting element in heat dissipation, and fixes the flexible connecting wire between the back side of the substrate and the heat dissipation fixing structure to form a stress relief section.

[0008] Furthermore, the heat dissipation fixing structure includes a thermally conductive adhesive layer and a heat sink; the thermally conductive adhesive layer is coated on the back side of the substrate and the flexible connecting line wrapped around the back side of the substrate; the heat sink is bonded and fixed to the outer side of the back side of the substrate by the thermally conductive adhesive layer, and the flexible connecting line is pressed and fixed between the back side of the substrate and the heat sink.

[0009] Furthermore, the positive and negative electrode pads on the front side of the substrate are covered with an insulating adhesive layer to achieve electrical insulation and mechanical reinforcement of the solder joints.

[0010] Furthermore, the external control section includes a constant current driving module and a pulse control module; the constant current driving module is electrically connected to the photostimulation module through the flexible connecting line, and is used to provide a constant driving current to the photostimulation module; the pulse control module is electrically connected to the control terminal of the constant current driving module, and is used to output a programmable pulse control signal to the constant current driving module to control the pulse width, stimulation frequency, duty cycle, stimulation duration and stimulation interval of the photostimulation module.

[0011] Furthermore, the external control section also includes an external power supply module and a switch module; the external power supply module is electrically connected to the power input terminal of the constant current drive module via the switch module, and is used to supply power to the constant current drive module; the switch module is disposed on the power supply line between the external power supply module and the constant current drive module, and is used to control the on / off state of the power supply line.

[0012] Furthermore, the photostimulation module is provided in multiple ways, and the constant current driving module is set up one-to-one with the photostimulation module; the control terminal of each constant current driving module is connected to different control ports of the same pulse control module to realize independent or synchronous control of multiple photostimulation modules.

[0013] Furthermore, the flexible connecting line is fixed to the surface of the wearable carrier by stitching fixation points, and the double-line portion of the flexible connecting line is fixed by heat shrink tubing.

[0014] Furthermore, one end and / or the other end of the flexible connecting line is provided with a miniature plug-in interface, which is used to enable quick plug-in connection between the wearable carrier and the external control part.

[0015] An optogenetic stimulation method, using the above-mentioned optogenetic stimulation device, includes: Based on the type of photosensitive protein expressed by the experimental animal, the wavelength of the light-emitting element in the photostimulation module is selected, and the number and installation position of the photostimulation module are determined according to the target tissue. The wearable carrier is worn on the body surface of the experimental animal, with the light-emitting surface of the photostimulation module facing the body surface area where the target tissue is located; The external control unit provides a driving signal to the photostimulation module, controlling the photostimulation module to output stimulation light according to preset stimulation parameters, and to perform optogenetic stimulation on the body surface or superficial target tissue of the experimental animal.

[0016] The beneficial effects of the optogenetic stimulation device provided in this application are as follows: Compared with the prior art, in this application, the wearable carrier serves as the fixed carrier for the optostimulation module, which can stably maintain the optostimulation module in the target stimulation area on the surface of the experimental animal. This effectively prevents the optostimulation module from shifting or falling off during the free movement of the experimental animal, ensuring the consistency of the stimulation position and the feasibility of repeated wearing. Simultaneously, the external control unit is detachably electrically connected to the optostimulation module via a flexible connecting cable. This facilitates the wearing of the vest by the experimental animal and the adjustment of the device, and also enables independent replacement and maintenance of the optostimulation module and the external control unit, avoiding device damage caused by repeated connections. Furthermore, the external control unit provides a drive signal to the optostimulation module, enabling the optostimulation module to output stimulation light according to preset parameters, achieving standardized control of the optostimulation parameters and improving the reproducibility between different experimental batches. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in the embodiments of this application, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0018] Figure 1 This is a schematic diagram of the optogenetic stimulation device provided in the embodiments of this application; Figure 2 This is a schematic diagram illustrating the control of multiple photostimulation modules used in the optogenetic stimulation device provided in the embodiments of this application. Figure 3 A schematic diagram of the optogenetic stimulation device provided in this application embodiment worn on an experimental animal; Figure 4 This is a schematic diagram of the structure of the photostimulation module in the photogenetic stimulation device provided in the embodiments of this application; Figure 5 A wiring diagram of the external control section in the optogenetic stimulation device provided in the embodiments of this application; Figure 6 This is a schematic diagram of parallel control of the multi-channel photostimulation module in the photogenetic stimulation device provided in the embodiments of this application.

[0019] The following are the labeling elements in the figure: 10-Laboratory animals; 100-Wearable component; 110-Wearable carrier; 120-Photostimulation module; 121-Light-emitting element; 122-Substrate; 123-Positive and negative electrode pads; 124-Thermal conductive adhesive layer; 125-Heat sink; 126-Insulating adhesive wrapping layer; 200 - External control section; 210 - Constant current drive module; 211 - PT4115 constant current drive module; 212 - Power input positive terminal; 213 - Power input negative terminal; 214 - Output positive terminal; 215 - Output negative terminal; 216 - DIM dimming / enable terminal; 217 - Ground terminal; 220 - Pulse control module; 221 - Arduino Nano microcontroller; 222 - D9 pin; 223 - Ground pin; 230 - External power supply module; 231 - DC power supply; 240 - Switch module; 300 - Flexible connecting wire; 301 - Stress relief section; 302 - Seam fixing point; 303 - Heat shrink tubing; 400-Miniature plug-in interface. Detailed Implementation

[0020] To make the technical problems, technical solutions, and beneficial effects to be solved by this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and are not intended to limit the scope of this application.

[0021] It should be noted that when a component is referred to as being "fixed to" or "set on" another component, it can be directly on or indirectly on that other component. When a component is referred to as being "connected to" another component, it can be directly connected to or indirectly connected to that other component.

[0022] It should be understood that the terms "length", "width", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application.

[0023] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this application, "multiple" means two or more, unless otherwise explicitly specified.

[0024] Please refer to the following: Figure 1 and Figure 3The optogenetic stimulation device provided in this application embodiment will now be described. This optogenetic stimulation device includes a wearable portion 100 and an external control portion 200; the wearable portion 100 is connected to an experimental animal 10, and the external control portion 200 is separate from the experimental animal 10; the wearable portion 100 includes a wearable carrier 110 and a photostimulation module 120; the wearable carrier 110 is worn on the body surface of the experimental animal 10; the photostimulation module 120 is fixedly disposed on the wearable carrier 110, with the light-emitting surface of the photostimulation module 120 facing the body surface or superficial target tissue of the experimental animal 10, for emitting stimulation light; the external control portion 200 is detachably electrically connected to the photostimulation module 120 via a flexible connecting cable 300; the external control portion 200 is used to provide a driving signal to the photostimulation module 120 to control the photostimulation module 120 to output stimulation light with preset parameters.

[0025] Compared with the prior art, the optogenetic stimulation device provided in this embodiment uses a wearable carrier 110 as a fixed carrier for the optostimulation module 120. This ensures that the optostimulation module 120 is stably maintained in the target stimulation area on the body surface of the experimental animal 10, effectively preventing the optostimulation module 120 from shifting position or falling off during the free movement of the experimental animal 10, thus guaranteeing the consistency of the stimulation position and the feasibility of repeated wear. Simultaneously, the external control unit 200 is detachably electrically connected to the optostimulation module 120 via a flexible connecting cable 300. This facilitates the wearing of the vest and device adjustment by the experimental animal 10, and also enables independent replacement and maintenance of the optostimulation module 120 and the external control unit 200, avoiding device damage caused by repeated connections. Furthermore, the external control unit 200 provides a drive signal to the optostimulation module 120, enabling the optostimulation module 120 to output stimulation light according to preset parameters, achieving standardized control of the optostimulation parameters and improving the reproducibility between different experimental batches.

[0026] In a preferred embodiment of this application, the wearable carrier 110 is a wearable vest. In this embodiment, the wearable vest is made of black elastic stocking material. This material is soft, lightweight, low-cost, and elastic, allowing it to fit snugly against the torso of the experimental animal 10, thus securing the photostimulation module 120 and part of the flexible connecting wires 300. Simultaneously, the black elastic stocking material provides some shielding against scattered and leaked light emitted by the photostimulation module 120, reducing light transmission to the external environment and thereby minimizing interference from leaked light on the animal's visual responses and behavioral observations. It is understood that the wearable carrier 110 is not limited to the wearable vest described above. In other embodiments, the wearable carrier 110 may also be made of any of the following: black elastic fabric, elastic mesh, nylon elastic fabric, neoprene sheet, flexible medical tape, adjustable strap, three-dimensional printed flexible vest, or other lightweight wearable fixation structure. As long as it can fix the photostimulation module 120 and allow the experimental animal 10 to move freely, it can be used as an alternative to the wearable carrier 110 of this application.

[0027] In one embodiment of this application, please refer to Figure 4 The photostimulation module 120 includes a light-emitting element 121, a substrate 122, and a heat dissipation fixing structure. The light-emitting element 121 is fixed to the front side of the substrate 122, and the flexible connecting line 300 is soldered to the positive and negative electrode pads 123 on the substrate 122. The heat dissipation fixing structure is disposed on the back side of the substrate 122 to assist the light-emitting element 121 in heat dissipation and to fix the flexible connecting line 300 between the back side of the substrate 122 and the heat dissipation fixing structure to form a stress relief section 301. Figure 4 In the diagram, A indicates that the flexible connecting line 300 bends from the front side of the substrate 122 to the back side of the substrate 122.

[0028] In this embodiment, the substrate 122 provides a support and initial heat conduction path for the light-emitting element 121. The heat generated by the light-emitting element 121 during operation is conducted through the substrate 122 to the heat dissipation and fixing structure on the back side. The heat dissipation and fixing structure dissipates the heat to the surrounding environment, preventing heat accumulation near the light-emitting element 121 and avoiding excessive local temperature rise, thereby ensuring animal safety and the operational stability of the light-emitting element 121. Simultaneously, the flexible connecting line 300 extends from the front side of the substrate 122, bypassing the edge, to the back side of the substrate 122. The heat dissipation and fixing structure presses and fixes the flexible connecting line 300, extending to the back side, between the back side of the substrate 122 and the heat dissipation and fixing structure, forming a stress-relieving section 301 near the solder joint. When the flexible connecting line 300 is subjected to external tensile force, the tensile force first acts on the stress-relieving section 301 fixed by the heat dissipation and fixing structure, rather than being directly transmitted to the solder joint on the front side of the substrate 122. This prevents the solder joint from detaching or breaking due to direct force, improving the connection reliability and service life of the device during free-movement experiments.

[0029] Specifically, the light-emitting element 121 can be an LED chip. When the photosensitizing protein expressed by the experimental animal 10 is a redshifted photosensitizing protein such as Chrimson, ChrimsonR, or ReaChR, the light-emitting element 121 can be an Amber LED chip with a center wavelength of approximately 590 nm, such as the Cree XLamp XP-E series Amber LED. This wavelength matches the activation wavelength of the aforementioned redshifted photosensitizing proteins, effectively activating them. The 590 nm wavelength of yellow-orange light has low scattering and relatively good tissue penetration in superficial tissues, which is beneficial for the stimulation light to reach the superficial target tissue.

[0030] It is understood that the light-emitting element 121 is not limited to the aforementioned Amber LED beads. In other embodiments, the light-emitting element 121 can also be replaced with blue LEDs, green LEDs, yellow LEDs, orange LEDs, red LEDs, or near-infrared LEDs, depending on the type of photosensitive protein expressed by the experimental animal 10, as long as its wavelength can activate the corresponding photosensitive protein. The number of light-emitting elements 121 can be one, two, or more. Multiple light-emitting elements 121 can be distributed in different positions on the same wearable carrier 110 or arranged on different wearable carriers 110 to adapt to the stimulation needs of different experimental areas or different animals.

[0031] The substrate 122 can be an LED aluminum substrate with a size of 12mm×12mm. It has both electrical insulation and thermal conductivity properties, which can not only carry LED beads and provide electrical connection, but also conduct the heat generated by the LED operation from the front side to the back side of the substrate 122.

[0032] It is understood that the installation location of the photostimulation module 120 is not limited to the above embodiments. In other embodiments, the photostimulation module 120 may also be installed on the surface of the experimental animal 10, such as the chest region, abdomen, back, flank, proximal limbs, or neck, depending on the target tissue of the experimental animal 10, to adapt to the photogenetic stimulation needs of the heart, gastrointestinal tract, peripheral nerves, superficial muscles, subcutaneous tissue, or other superficial target areas.

[0033] In one embodiment of this application, please refer to Figure 4 The heat dissipation fixing structure includes a thermally conductive adhesive layer 124 and a heat sink 125. The thermally conductive adhesive layer 124 is coated on the back side of the substrate 122 and on the flexible connecting line 300 that wraps around the back side of the substrate 122. The heat sink 125 is bonded and fixed to the outer side of the back side of the substrate 122 by the thermally conductive adhesive layer 124, and the flexible connecting line 300 is pressed and fixed between the back side of the substrate 122 and the heat sink 125.

[0034] In this embodiment, the thermally conductive adhesive layer 124 serves a dual function of thermal conduction and bonding. It enables rapid heat transfer from the light-emitting element 121 from the substrate 122 to the heat sink 125, while also firmly securing the flexible connecting wire 300 to the back of the substrate 122. The heat sink 125 is bonded to the outer back of the substrate 122 via the thermally conductive adhesive layer 124. The large area of ​​the heat sink 125 effectively increases the heat dissipation area and improves heat dissipation efficiency. Simultaneously, the heat sink 125, through the thermally conductive adhesive layer 124, presses and fixes the flexible connecting wire 300, which winds around the back of the substrate 122, between the back of the substrate 122 and the heat sink 125, forming a reliable mechanical fixing structure. When the flexible connecting wire 300 is subjected to external tensile force, the pressing and fixing structure effectively bears and disperses the tensile force, preventing direct stress on the solder joints, further improving the reliability of the solder joint connection and the overall durability of the device.

[0035] Specifically, the thermally conductive adhesive layer 124 can be made of thermally conductive silicone, such as a cured thermally conductive silicone, with a thermal conductivity of 4 W / m·K. The heat sink 125 can be made of copper sheet with dimensions of 0.1 mm × 15 mm × 15 mm. The thermally conductive silicone has good thermal conductivity and adhesive strength, which can firmly bond the copper sheet to the substrate 122 while conducting heat, and at the same time provide reliable pressure and fixation for the flexible connecting line 300; the copper sheet has good thermal conductivity and flexibility, and the large-area thin sheet structure can effectively increase the heat dissipation area and improve the heat dissipation efficiency without significantly burdening the free movement of the experimental animal 10.

[0036] In one embodiment of this application, please refer to Figure 4 An insulating adhesive coating layer 126 is applied to the positive and negative electrode pads 123 on the front side of the substrate 122 to achieve electrical insulation and mechanical reinforcement of the solder joints.

[0037] In this embodiment, the insulating adhesive coating layer 126 covers the positive and negative electrode pads 123 and solder joint surfaces on the front side of the substrate 122. On the one hand, it serves as electrical insulation to prevent short circuits between the positive and negative electrode pads 123 or between the solder joints and external conductors. On the other hand, it provides mechanical reinforcement to the solder joints, enhancing the bonding strength between the solder joints and the substrate 122, reducing stress concentration at the solder joints when the flexible connecting line 300 is subjected to slight vibration or tension, and further improving the long-term reliability of the solder joints and the service life of the device.

[0038] In one embodiment of this application, please refer to the following: Figure 1 and Figure 5The external control unit 200 includes a constant current drive module 210 and a pulse control module 220. The constant current drive module 210 is electrically connected to the photostimulation module 120 via a flexible connecting line 300 and is used to provide a constant drive current to the photostimulation module 120. The pulse control module 220 is electrically connected to the control terminal of the constant current drive module 210 and is used to output a programmable pulse control signal to the constant current drive module 210 to control the pulse width, stimulation frequency, duty cycle, stimulation duration and stimulation interval of the photostimulation module 120.

[0039] In this embodiment, the constant current driving module 210 provides a constant driving current to the photostimulation module 120, enabling the light-emitting element 121 to maintain a stable light output intensity under different operating conditions and avoiding light intensity drift caused by power supply voltage fluctuations or temperature changes. The pulse control module 220, by outputting a programmable pulse control signal to the constant current driving module 210, can precisely set the pulse width, stimulation frequency, duty cycle, stimulation duration, and stimulation interval of the photostimulation, achieving flexible programming and standardized output of the photostimulation time-domain parameters. This meets the differentiated stimulation mode requirements of different optogenetic experiments and improves reproducibility within the same experiment and between different experimental batches. Through the cooperation of the constant current driving module 210 and the pulse control module 220, a general-purpose, low-cost device replaces the high-cost commercial photostimulation driver, reducing device setup costs and procurement difficulties, and facilitating rapid replication in ordinary laboratories.

[0040] Specifically, such as Figure 5 As shown, the constant current drive module 210 can be a PT4115 constant current drive module 211, which has the characteristics of small size, simple peripheral circuit, wide adjustable output current range and high constant current accuracy, and is suitable for driving low power LED light-emitting elements 121.

[0041] like Figure 5As shown, the pulse control module 220 can use an Arduino Nano microcontroller 221, which connects to a computer via a USB cable and uses the Arduino IDE software to write and upload control programs. The Arduino Nano microcontroller 221 has multiple digital output pins, which can be programmed to flexibly generate pulse width modulation signals with different frequencies and duty cycles. The signal output pins of the Arduino Nano microcontroller 221 (such as pin D9 222) are connected to the DIM dimming / enable terminal 216 of the PT4115 constant current drive module 211, and the ground pin 223 of the Arduino Nano microcontroller 221 is connected to the ground terminal 217 of the PT4115 constant current drive module 211. The signal output pin of the Arduino Nano microcontroller 221 is used to output a PWM pulse control signal. The DIM dimming / enable pin 216 of the PT4115 constant current drive module 211 is used to receive the PWM signal and control the switching transistor inside the PT4115 constant current drive module 211 to turn on and off according to the high or low level of the pulse control signal. This allows the driving current flowing through the light-emitting element 121 in the photostimulation module 120 to be switched on and off according to the time domain law of the pulse control signal, thereby achieving precise control of the photostimulation pulse width, stimulation frequency, duty cycle, stimulation duration and stimulation interval.

[0042] For example, pulse outputs with a pulse width of 10ms, a frequency of 10Hz or 15Hz, and illumination patterns with specific stimulation cycles can be achieved through program settings. The PT4115 constant current drive module 211 and the Arduino Nano microcontroller 221 are both commercially available, general-purpose, low-cost devices. Compared to high-cost commercial photostimulation drivers and their accessories, they significantly reduce the cost of device setup and improve the flexibility of self-reproduction and parameter customization in ordinary laboratories.

[0043] It is understood that the pulse control module 220 is not limited to the Arduino Nano microcontroller 221 described above. In other embodiments, the pulse control module 220 may also be any of the following: Arduino Uno, Arduino Pro Mini, ESP32, STM32, RP2040, microcontroller development board, data acquisition card, function generator, transistor-to-transistor logic level triggering device, or other control device capable of outputting digital pulse signals, as long as it can output programmable pulse control signals to the constant current drive module 210.

[0044] It is understood that the control method is not limited to the method of writing and uploading control programs through the Arduino IDE software. In other embodiments, the control method can also adopt any of the following: computer serial port control, external trigger control, synchronous trigger control of behavioral devices, or closed-loop feedback control, as long as it can send control commands to the pulse control module 220 to set the photostimulation parameters.

[0045] In one embodiment of this application, please refer to the following: Figure 1 and Figure 5 The external control unit 200 also includes an external power supply module 230 and a switch module 240; the external power supply module 230 is electrically connected to the power input terminal of the constant current drive module 210 via the switch module 240, and is used to supply power to the constant current drive module 210; the switch module 240 is disposed on the power supply line between the external power supply module 230 and the constant current drive module 210, and is used to control the on / off state of the power supply line.

[0046] In this embodiment, the external power supply module 230 provides operating power to the constant current drive module 210. The switch module 240 is located on the power supply line between the external power supply module 230 and the constant current drive module 210. By controlling the on / off state of the switch module 240, the power supply to the constant current drive module 210 and the photostimulation module 120 can be controlled, facilitating equipment power-on / off and emergency power-off operations during experiments. The external power supply module 230 can use a general-purpose DC power supply, reducing the overall cost of the device and improving power supply compatibility.

[0047] Specifically, the external power supply module 230 uses a 12V, 2A, 24W DC power supply 231. The positive terminal of the DC power supply 231 is connected to one end of the switching module 240, and the other end of the switching module 240 is connected to the positive power input terminal 212 of the constant current drive module 210; the negative terminal of the DC power supply 231 is connected to the negative power input terminal 213 of the constant current drive module 210. The switching module 240 is fixedly mounted on the positive input line of the DC power supply 231 and is used to control the power on and off of the entire drive circuit. The positive output terminal 214 and the negative output terminal 215 of the constant current drive module 210 are respectively connected to the positive and negative pads 123 on the substrate 122.

[0048] In this embodiment, the constant current output current of the PT4115 constant current drive module 211 is set to 500mA to obtain a higher electrical input power and corresponding light output of the light-emitting element 121, facilitating the application of light to the superficial target tissue of the experimental animal 10. Based on the estimated forward voltage of approximately 3.1V to 3.3V for a Cree XP-E Amber LED under 500mA conditions, the electrical input power of a single LED is approximately 1.55W to 1.65W. Assuming an LED chip area of ​​2mm × 2mm, the corresponding electrical input power surface density is approximately 387.5mW / mm² to 412.5mW / mm². This value is an estimated electrical input power calculated based on the LED chip area and is not equivalent to the actual light power density; the actual light power density should be determined by actual measurement using a power meter at the LED light-emitting surface or the animal's body surface.

[0049] It is understood that the external power supply module 230 is not limited to the aforementioned 12V, 2A, 24W DC power supply 231. In other embodiments, the external power supply module 230 may also adopt any of the following, depending on the number of light-emitting elements 121, the driving current, and the requirements of the driving circuit: 5V, 9V, 12V, 24V DC power supply, laboratory DC regulated power supply, rechargeable battery pack, mobile power supply boost module, or isolated power supply module, as long as it can provide a stable operating voltage and sufficient output power to the constant current drive module 210.

[0050] In this embodiment, the switch module 240 can be a toggle switch. In other embodiments, the switch module 240 can also be a push-button switch, a relay, an electronic switch, or a controlled power management module. It is acceptable as long as it can be installed on the power supply line between the external power supply module 230 and the constant current drive module 210 to control the on / off state of the power supply line.

[0051] In another embodiment of this application, please refer to [the relevant document / reference]. Figure 2 and Figure 6 The photostimulation module 120 is provided in multiple ways, and the constant current drive module 210 is set one-to-one with the photostimulation module 120; the control terminal of each constant current drive module 210 is connected to different control ports of the same pulse control module 220 to realize independent or synchronous control of multiple photostimulation modules 120.

[0052] In this embodiment, by setting up multiple photostimulation modules 120 and corresponding multiple constant current drive modules 210, and connecting the control terminals of each constant current drive module 210 to different control ports of the same pulse control module 220, a single pulse control module 220 can simultaneously manage multiple photostimulation outputs. Each photostimulation module 120 can be controlled independently or synchronously. Since each photostimulation module 120 is relatively independent, photostimulation of different frequencies or durations can be applied to different body surface areas according to experimental requirements, thereby meeting the needs of complex experimental scenarios such as bilateral stimulation, multi-region stimulation, or synchronous stimulation of multiple animals, effectively expanding the application range of the device, and reducing the system construction cost of multi-channel parallel experiments.

[0053] Specifically, please refer to Figure 6 Each constant current drive module 210 can be a PT4115 constant current drive module 211, and the pulse control module 220 can be an Arduino Nano microcontroller 221. The positive power input terminals 212 of multiple PT4115 constant current drive modules 211 are connected in parallel to the positive bus of the same external power supply module 230, and the negative power input terminals 213 of multiple PT4115 constant current drive modules 211 are connected in parallel to the negative bus of the same external power supply module 230, thus achieving parallel power supply for each constant current drive module 210. The DIM dimming / enable terminal 216 of each PT4115 constant current drive module 211 is connected to different digital output ports of the Arduino Nano microcontroller 221, such as D9, D10, and D11, to achieve independent pulse control of the multi-channel photostimulation module 120. The ground terminal 217 of the Arduino Nano microcontroller 221 is connected to the ground terminal 217 of each PT4115 constant current drive module 211, thereby ensuring that the pulse control signal can be stably recognized by each PT4115 constant current drive module 211. The positive output terminal 214 and the negative output terminal 215 of each PT4115 constant current drive module 211 are respectively connected to the positive and negative electrode pads 123 on the substrate 122 of their respective photostimulation module 120.

[0054] By writing control programs for different digital output ports in the Arduino Nano microcontroller 221, the pulse width, stimulation frequency, duty cycle, stimulation duration, and stimulation interval of each photostimulation module 120 can be set separately. For example, different digital output ports can output pulse signals of 10Hz, 15Hz, or other preset frequencies, thereby realizing independent photostimulation control of multiple regions, different frequencies, or different stimulation cycles.

[0055] Therefore, the embodiments of this application can be expanded into bilateral stimulation, multi-region stimulation, multi-frequency stimulation, or simultaneous stimulation systems for multiple animals, depending on experimental needs. In use, firstly, the luminescent element 121 with the corresponding wavelength is selected according to the photosensitive protein required for the experiment, and the stimulation program is set through the pulse control module 220, thus enabling controllable, stable, and repeatable photogenetic stimulation of the body surface of freely moving animals.

[0056] In one embodiment of this application, please refer to the following: Figure 3 and Figure 4 The flexible connecting line 300 is fixed to the surface of the wearable carrier 110 through the stitching fixing point 302, and the double-line portion of the flexible connecting line 300 is fixed by the heat shrink tubing 303.

[0057] In this embodiment, the flexible connecting wire 300 is fixed to the surface of the wearable carrier 110 through the stitching fixation point 302, forming a multi-point fixation on the surface of the wearable carrier 110. When the flexible connecting wire 300 is subjected to external tension, the tension first acts on the stitching fixation point 302 and is borne and dispersed by the material of the wearable carrier 110, reducing the intensity of the tension transmitted to the photostimulation module 120 and further reducing the stress burden on the solder joint and stress relief section 301. At the same time, the double-wire portion of the flexible connecting wire 300 is fixed by the heat shrink tubing 303, keeping the positive and negative wires closely parallel, reducing the relative shaking and tangling of the wires during animal activity, and improving the neatness of the wiring and the stability of the connection. Through the cooperation of the stitching fixation point 302 and the heat shrink tubing 303, the fixation of the flexible connecting wire 300 along the surface of the wearable carrier 110 is more reliable, which helps to reduce the risk of connection failure caused by cable shaking or pulling during free movement experiments.

[0058] Specifically, the flexible connecting wire 300 can use 30 AWG fine wire, which is flexible and lightweight, making it suitable for experimental devices for small animals such as mice, reducing interference with the animals' free movement.

[0059] It is understood that the flexible connecting wire 300 is not limited to the aforementioned 30 AWG fine gauge wire. In other embodiments, the flexible connecting wire 300 may also be any of the following: 28 AWG to 34 AWG silicone wire, enameled wire, fluoroplastic insulated wire, flexible ribbon cable, flexible printed circuit board, or other lightweight conductive connectors, as long as it can achieve the electrical connection between the photostimulation module 120 and the external control part 200 and has the characteristics of flexibility and lightweight.

[0060] It is understood that in other embodiments, the stress relief section 301 may also be formed by any of the following methods: adhesive, sewing, cable ties, buckles, clips, flexible encapsulation, or cable fixing base, as long as it can fix the flexible connecting line 300 to the wearable carrier 110 or the heat dissipation fixing structure, so that the flexible connecting line 300 forms a stress dispersion structure near the solder joint.

[0061] In one embodiment of this application, please refer to Figure 5 One end and / or the other end of the flexible connection cable 300 is provided with a miniature plug-in interface 400, which is used to realize quick plug-in connection between the wearable carrier 110 and the external control part 200.

[0062] In this embodiment, one and / or the other end of the flexible connecting line 300 is provided with a miniature plug-in interface 400. Through the mating of the male and female connectors of the miniature plug-in interface 400, a quick plug-in connection can be achieved between the wearable carrier 110 and the external control unit 200. When the experimental animal 10 needs to wear the vest for experiments, the electrical connection can be completed simply by quickly connecting the plug at the vest end to the socket at the external control circuit end. When the experiment is over or the vest needs to be replaced or the photostimulation module 120 needs to be adjusted, the vest end can be separated from the external control unit 200 simply by unplugging the plug. This quick plug-in structure effectively simplifies the operation process of animal wearing, device debugging, photostimulation module 120 replacement, and vest cleaning, avoiding connection damage caused by repeated disassembly and assembly in traditional welding or screw fixing methods, and improving the practicality and maintenance convenience of the device. At the same time, the miniature plug-in interface 400 is small in size and lightweight, suitable for the lightweight requirements of experimental devices for small animals such as mice, and will not significantly burden the free movement of the experimental animal 10.

[0063] Specifically, the miniature pluggable interface 400 can adopt a 1.0mm pitch dual-pin pluggable interface, such as the JST-SH 1.0mm pitch 2P interface. This interface includes a female connector located at the end of the flexible connecting line 300 near the wearable carrier 110 and a male connector located at the end of the flexible connecting line 300 near the external control part 200. The female and male connectors cooperate to form a pluggable connection. The 1.0mm pitch dual-pin pluggable interface is small in size and lightweight, suitable for the lightweight requirements of experimental devices for small animals such as mice, and can effectively reduce interference with the animal's free movement. At the same time, its plugging and unplugging operation is simple and the connection is reliable, suitable for usage scenarios where the vest needs to be frequently worn and removed during experiments.

[0064] It is understood that the miniature plug-in interface 400 is not limited to the aforementioned JST-SH 1.0mm pitch 2P interface. In other embodiments, the miniature plug-in interface 400 may also adopt any of the following: JST-GH interface, Molex miniature connector, magnetic connector, miniature aviation plug, board-to-wire connector, spring pin connector, or other lightweight quick-plug interfaces suitable for small animal wearable devices, as long as it can achieve quick plug-in connection between the wearable carrier 110 and the external control part 200 and is small in size and light in weight.

[0065] An optogenetic stimulation method, using the above-mentioned optogenetic stimulation device, includes: Based on the type of photosensitive protein expressed by the experimental animal 10, the wavelength of the light-emitting element 121 in the photostimulation module 120 is selected, and the number and installation position of the photostimulation module 120 are determined according to the target tissue. The wearable carrier 110 is worn on the body surface of the experimental animal 10, and the light-emitting surface of the light stimulation module 120 is facing the body surface area where the target tissue is located. The external control unit 200 provides a driving signal to the photostimulation module 120, controlling the photostimulation module 120 to output stimulation light according to preset stimulation parameters, and to perform photogenetic stimulation on the body surface or superficial target tissue of the experimental animal 10.

[0066] The optogenetic stimulation method provided in this application first selects the wavelength of the light-emitting element 121 according to the type of photosensitive protein, and determines the number and installation position of the photostimulation modules 120 according to the target tissue. This allows the device to adapt to the experimental needs of different photosensitive proteins and different superficial target tissues, thus having wide applicability. Then, the photostimulation modules 120 are stably worn on the target area of ​​the experimental animal 10 through a wearable carrier 110, ensuring that the photostimulation modules 120 can continuously align with the target tissue during the animal's free movement, guaranteeing the stability of the stimulation position. Finally, the external control unit 200 provides a driving signal to the photostimulation modules 120, causing the photostimulation modules 120 to output stimulation light according to preset stimulation parameters (such as pulse width, frequency, duty cycle, stimulation duration, and stimulation interval), achieving precise control of the time-domain parameters of the photostimulation. The entire method is simple to operate and can effectively improve the consistency and reproducibility of optogenetic stimulation, making it suitable for optogenetic research on various superficial target areas such as the heart, gastrointestinal tract, peripheral nerves, superficial muscles, and subcutaneous tissues.

[0067] It is understood that the optogenetic stimulation methods provided in this application are not limited to optogenetic activation. In other embodiments, the above methods can also be used for optogenetic inhibition, photoreceptor modulation, superficial tissue photostimulation, transdermal photostimulation, validation of photosensitive protein expression, behavioral synchronous photostimulation, cardiac rhythm modulation, gastrointestinal function modulation, peripheral nerve modulation, muscle activity modulation, and other animal experiments requiring low-cost wearable localized illumination. The above methods are not limited to optogenetic stimulation of the body surface of freely moving mice, but can also be used for photostimulation experiments of the body surface or superficial target areas of other experimental small animals.

[0068] In this embodiment of the application, mice were used as experimental animals for verification experiments. DBH-Cre mice were used, and 4-month-old mice were injected bilaterally into the locus coeruleus with the Cre-dependent viral vector rAAV-hSyn-DIO-rsChRmine-mCherry. After viral injection, the mice were fed for another 5 weeks to allow the redshifted light-sensitive protein rsChRmine-mCherry to be fully expressed in DBH-positive cells.

[0069] During the light stimulation experiment, the abdominal skin corresponding to the liver projection area of ​​the mice was shaved, and the light stimulation module 120 was fixed to this area with the light-emitting surface facing the skin. Light stimulation used a 10ms pulse width and a 15Hz stimulation frequency; within each 2s stimulation cycle, a 500ms pulse light stimulation was first applied, followed by a 1500ms pause. The constant current output current of the constant current drive module 210 was set to 400mA.

[0070] In the multi-channel experiment, four constant current driving modules 210 and four photostimulation modules 120 were connected. Each constant current driving module 210 drove one photostimulation module 120 and corresponded to one experimental mouse. Each driving channel operated in parallel according to a preset program, enabling simultaneous surface photostimulation of four mice with the same parameters. Actual usage results showed that all four photostimulation channels operated normally according to the preset pulse width, stimulation frequency, stimulation time, and shutdown interval, enabling parallel surface photostimulation of multiple mice. The wearable carrier 110 fixed the photostimulation module 120 to the shaved liver area abdominal skin, meeting the requirements of relatively stable target light position and repetitive multi-channel stimulation during the experiment. Therefore, from the aspects of device assembly, constant current driving, pulse control, animal wearing, and parallel operation of the four channels, the optogenetic stimulation device and method provided in this application embodiment are preliminarily demonstrated to be feasible and have practical application value.

[0071] The above description is merely a preferred embodiment of this application and is not intended to limit this application. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. An optogenetic stimulation device, characterized in that, include: Wearable carrier, the wearable carrier being worn on the body surface of an experimental animal; A photostimulation module is fixedly mounted on the wearable carrier, with the light-emitting surface of the photostimulation module facing the body surface or superficial target tissue of the experimental animal, for emitting stimulating light; The external control section is detachably electrically connected to the photostimulation module via a flexible connecting cable; the external control section is used to provide a drive signal to the photostimulation module to control the photostimulation module to output stimulation light with preset parameters.

2. The optogenetic stimulation device as described in claim 1, characterized in that, The photostimulation module includes a light-emitting element, a substrate, and a heat dissipation and fixing structure; The light-emitting element is fixed to the front side of the substrate, and the flexible connecting line is soldered to the positive and negative electrode pads on the substrate; The heat dissipation fixing structure is disposed on the back side of the substrate to assist the heat dissipation of the light-emitting element, and fixes the flexible connecting line between the back side of the substrate and the heat dissipation fixing structure to form a stress relief section.

3. The optogenetic stimulation device as described in claim 2, characterized in that, The heat dissipation fixing structure includes a thermally conductive adhesive layer and a heat sink; The thermally conductive adhesive layer is coated on the back side of the substrate and on the flexible connecting line wrapped around the back side of the substrate; The heat sink is bonded and fixed to the outer side of the back of the substrate by the thermally conductive adhesive layer, and the flexible connecting wire is pressed and fixed between the back of the substrate and the heat sink.

4. The optogenetic stimulation device as described in claim 2, characterized in that, The positive and negative electrode pads on the front side of the substrate are covered with an insulating adhesive layer to achieve electrical insulation and mechanical reinforcement of the solder joints.

5. The optogenetic stimulation device as described in claim 1, characterized in that, The external control section includes a constant current drive module and a pulse control module; the constant current drive module is electrically connected to the photostimulation module through the flexible connection line, and is used to provide a constant drive current to the photostimulation module; The pulse control module is electrically connected to the control terminal of the constant current drive module and is used to output a programmable pulse control signal to the constant current drive module to control the pulse width, stimulation frequency, duty cycle, stimulation duration and stimulation interval of the photostimulation module.

6. The optogenetic stimulation device as described in claim 5, characterized in that, The external control section also includes an external power supply module and a switch module; the external power supply module is electrically connected to the power input terminal of the constant current drive module via the switch module, and is used to supply power to the constant current drive module; The switch module is located on the power supply line between the external power supply module and the constant current drive module, and is used to control the on / off state of the power supply line.

7. The optogenetic stimulation device as described in claim 5, characterized in that, The photostimulation module is provided in multiple ways, and the constant current driving module is set up one-to-one with the photostimulation module; the control terminal of each constant current driving module is connected to different control ports of the same pulse control module to realize independent or synchronous control of multiple photostimulation modules.

8. The optogenetic stimulation device as claimed in claim 1, characterized in that, The flexible connecting line is fixed to the surface of the wearable carrier by stitching fixation points, and the double-line portion of the flexible connecting line is fixed by heat shrink tubing.

9. The optogenetic stimulation device according to any one of claims 1-8, characterized in that, One end and / or the other end of the flexible connecting line is provided with a miniature plug-in interface, which is used to enable quick plug-in connection between the wearable carrier and the external control part.

10. A method for optogenetic stimulation, using the optogenetic stimulation device as described in any one of claims 1-9, characterized in that, include: Based on the type of photosensitive protein expressed by the experimental animal, the wavelength of the light-emitting element in the photostimulation module is selected, and the number and installation position of the photostimulation module are determined according to the target tissue. The wearable carrier is worn on the body surface of the experimental animal, with the light-emitting surface of the photostimulation module facing the body surface area where the target tissue is located; The external control unit provides a driving signal to the photostimulation module, controlling the photostimulation module to output stimulation light according to preset stimulation parameters, and to perform optogenetic stimulation on the body surface or superficial target tissue of the experimental animal.

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