Detailed Description
In order that the above objects, features and advantages of the invention will be readily understood, a more particular description of the invention will be rendered by reference to the appended drawings. In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present invention. The present invention may be embodied in many other forms than described herein and similarly modified by those skilled in the art without departing from the spirit of the invention, whereby the invention is not limited to the specific embodiments disclosed below.
In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings are merely for convenience in describing the present invention and simplifying the description, and do not indicate or imply that the device or element being referred to must have a specific orientation, be configured and operated in a specific orientation, and therefore should not be construed as limiting the present invention.
Furthermore, the terms "first," "second," and the like, are used for descriptive purposes only and are not to be construed as indicating or implying a relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defining "a first" or "a second" may explicitly or implicitly include at least one such feature. In the description of the present invention, the meaning of "plurality" means at least two, for example, two, three, etc., unless specifically defined otherwise.
In the present invention, unless explicitly specified and limited otherwise, the terms "mounted," "connected," "secured," and the like are to be construed broadly, and may be, for example, fixedly connected, detachably connected, or integrally formed; can be mechanically or electrically connected; either directly or indirectly, through intermediaries, or both, may be in communication with each other or in interaction with each other, unless expressly defined otherwise. The specific meaning of the above terms in the present invention can be understood by those of ordinary skill in the art according to the specific circumstances.
In the present invention, unless expressly stated or limited otherwise, a first feature "up" or "down" a second feature may be the first and second features in direct contact, or the first and second features in indirect contact via an intervening medium. Moreover, a first feature being "above," "over" and "on" a second feature may be a first feature being directly above or obliquely above the second feature, or simply indicating that the first feature is level higher than the second feature. The first feature being "under", "below" and "beneath" the second feature may be the first feature being directly under or obliquely below the second feature, or simply indicating that the first feature is less level than the second feature.
It will be understood that when an element is referred to as being "fixed" or "disposed" on another element, it can be directly on the other element or intervening elements may also be present. When an element is referred to as being "connected" to another element, it can be directly connected to the other element or intervening elements may also be present. The terms "vertical," "horizontal," "upper," "lower," "left," "right," and the like are used herein for illustrative purposes only and are not meant to be the only embodiment.
The existing brain tumor treatment scheme is mainly a conservative treatment method in nature, including methods of surgical excision, chemotherapy, radiotherapy, immunotherapy and the like, but surgical operations such as radiotherapy, chemotherapy and the like can cause serious nerve function damage, and the difficulties of obstruction of a blood brain barrier to drug delivery, complexity of tumor microenvironment, heterogeneity of tumor tissues, drug tolerance and the like also need to be overcome. Due to the high recurrence rate and lack of effective treatment regimen, especially the majority of patients diagnosed with glioblastoma have a survival rate of <10% within 5 years even after receiving treatment with traditional therapies. Moreover, the type, size and location of the tumor, as well as the age, medical history, general health, symptom type and possible side effects of the patient, are all considered in an omni-directional, multi-angular manner during the treatment, which adds a number of difficulties to the design of the treatment regimen.
At present, a plurality of researches and equipment applications TTFields are used for treating tumors, but the existing treatment technology mainly comprises electrode implantation treatment and patch electrode placement on the scalp of a patient for treatment, wherein the patch electrode is attached to the scalp of the patient for a long time to cause mild dermatitis and moderate dermatitis, and the patient must shave the head every 3-4 days, so that the physiological discomfort and psychological burden of the patient in the treatment process are increased; secondly, the patch electrode adopted by the current electric field treatment technology cannot be close to the tumor cell position, the treatment effect is low, the treatment accuracy is insufficient, the patch electrode is required to be connected to an external battery through a long lead, the external battery is required to be carried all the time, and the application range and the object of the patch electrode are limited.
The wireless implantable medical device can alleviate the above problems to a certain extent, but the current wireless energy transmission mode mainly comprises near-field inductive coupling, far-field radio frequency electromagnetic wave, midfield inductive coupling, light, ultrasound and the like, and the voltage and current are mainly induced by an externally-driven implanted bioelectric receiver, which is mostly influenced by the size of the device, the receiving distance, the complexity of organism tissues and the like, so that the transmission power is low, the power consumption is high, and the treatment effect is poor.
Referring to fig. 1, the present application firstly provides an optical signal response power generation sheet, which includes a light-permeable packaging layer 10 and a power generation assembly 20 disposed inside the packaging layer 10, wherein the power generation assembly 20 includes a first film layer 21, a second film layer 22 and a third film layer 23 which are sequentially fixed, a micro-nano wire array is embedded in the first film layer 21, the third film layer 23 is a conductive material layer, and the micro-nano wire array can receive optical signals to form a potential difference.
In the application, near infrared signals are identified through the micro-nano wire array, signal conversion is realized, external near infrared light signals are converted into electrical signals in the equipment and output, the generated electrical signals can realize the treatment of specific brain tumors, and the micro-nano wire array has ultrahigh light-dark current ratio, high response speed and excellent stability and can meet the wireless energy transmission requirement of the implanted patch electrode.
The first thin film layer 21 is embedded with a micro-nanowire array, which means that the micro-nanowire array is directly grown on the first thin film layer 21, and the first thin film layer 21 is taken as a carbon fiber textile material (CFF) as an example, carbon fibers under a microscopic level are in a net structure, and the micro-nanowire array is vertically grown in the net structure, so that light can be irradiated to the first thin film layer 21 through the encapsulation layer 10.
In some embodiments, the micro-nanowire array includes a first micro-nanowire layer and a second micro-nanowire layer, both forming a heterojunction.
Taking Te NWs (tellurium nanowire array) as an example, in the original Te NWs, photogenerated carriers are easy to combine with each other in a long migration process, and obvious electric signal output is difficult to form.
In some embodiments, the first micro-nanowire layer is a tellurium micro-nanowire layer (tellurium nanowire array) and the second micro-nanowire layer is a tellurium-selenium micro-nanowire layer (tellurium-selenium alloy nanowire array).
Se (selenium) is a homologous and adjacent element of Te (tellurium), has the same external electronic structure and similar chemical and physical properties, and when Te and Se form an alloy, teSe (tellurium selenium alloy) has a lattice structure similar to that of Te crystals, and can be considered as Se replaces atoms in Te NWs.
By adopting the same deposition method, teSe NWs (tellurium-selenium alloy nanowire array) is covered on the Te NWs array, and the construction of the heterojunction can effectively regulate and control the carrier transmission between Te NWs and TeSe NWs (Te@TeSe NWs). In summary, an internal electric field is formed at the interface in the direction from Te NWs to TeSe NWs, and a type II heterojunction is formed, when te@tese NW is illuminated by near infrared light, the photogenerated carriers of the depletion region are affected by the internal electric field, photogenerated electrons are transferred to Te NWs, and photogenerated holes are transferred to TeSe NWs, so that the probability of recombination between carriers is reduced, the service life of carriers is prolonged, te NWs on the surface of te@tese NWs form a hole transport layer from the view of carrier migration process, and Te NWs in the core form an electron transport layer.
Compared with pure Te NWs, the method avoids the migration of holes and electrons in the same medium, reduces the recombination probability, prolongs the service life of carriers of Te@TeSe NWs, ensures that the device has a mechanism with higher responsivity and light guide gain under periodic illumination, and has the characteristics of stability, short response time and self power supply.
Specifically, in experiments, the heterostructure reaches a thermal equilibrium state by means of thermal motion of electron holes without illumination, and the valence and conduction bands are also in equilibrium.
When te@tese NWs are illuminated, the photogenerated carriers of the depletion region are affected by the internal electric field, photogenerated electrons are transferred to Te NWs, and photogenerated holes are transferred to TeSe NWs. Thus, electrons accumulate in Te NWs and holes accumulate in TeSe NWs, resulting in a difference in charge distribution between the two sides of te@tese NW, creating a potential difference; due to the new electron-hole pairs in the heterostructure, electrons and holes migrate to opposite sides, creating unbalanced carrier accumulation.
Therefore, the potential is formed by the difference of space charge distribution, and when an external circuit is connected to form a loop, the micro-nanowire array provides corresponding potential output according to light so as to complete the conversion from an optical signal to an electric signal; the source of the optical signal can be changed, and the source comprises infrared radiation, special communication light waves or a linear laser and the like; the generated electric signals can be controlled by structural design and micro-nano wire arrays, and then specific voltage and specific current can be generated by the tuning equipment, so that the brain tumor can be treated.
Of course, the first micro-nanowire layer and the second micro-nanowire layer may be other elements, so long as heterojunction can be formed, and migration of holes and electrons in the same medium is avoided, and the application is not limited herein.
In some embodiments, the atomic number ratio of tellurium element to selenium element in the tellurium-selenium micro-nanowire layer is 1:1.
It can be appreciated that when Te and Se form an atomic number ratio of 1:1, the lattice structure of the alloy is similar to that of Te crystals, and can be seen as Se replaces half of atoms in Te NWs; therefore, the ordinal number ratio of 1:1 is the best choice, if the ordinal number ratio is 1:2, 1:3 or other ratios, the metal with less ordinal number in the alloy is considered to replace a small part of atoms of the other metal, only a small improvement can be obtained, the photo-generated carriers are still easy to combine with each other in a long migration process, more obvious electric signal output and higher voltage are difficult to form, and therefore, the best effect cannot be achieved.
In some embodiments, the material of the first film layer 21 is one or more of carbon fiber textile material, high molecular polymer material, polydimethylsiloxane, polyester resin, thermoplastic polyurethane elastomer, soft polyvinyl chloride, or biaxially oriented polypropylene.
Preferably, the material of the first film layer 21 is carbon fiber textile material, and small-particle organic impurities are removed through ultrasonic cleaning, so that the flexibility and corrosion resistance of the fiber textile material are good, the durability and flexibility of the device are ensured, and skin tissues or organism tissues can be better attached.
Besides, as long as the characteristics of softness, ultra-thinness and good biocompatibility are satisfied, different materials and methods can be used for manufacturing the first film layer 21, for example, a film with a specific thickness can be manufactured by using a high polymer material (PDMS), so that not only is the flexibility good, but also the thickness control requirement can be satisfied, and the first film layer 21 is manufactured by using polymer materials such as PET (polydimethylsiloxane), TPU (polyester resin), TPE (thermoplastic polyurethane elastomer), soft PVC (soft polyvinyl chloride) or BOPP (biaxially oriented polypropylene), and the like, so that good mechanical properties such as wear resistance, heat resistance, good dimensional stability and the like are added on the basis of the original properties.
In some embodiments, the material of the second film layer 22 is one or more of polymethyl methacrylate, polycarbonate, polyester resin, polysulfone, polyvinyl chloride, or polydimethylsiloxane.
Preferably, the material of the second film layer 22 is PMMA (polymethyl methacrylate), which has strong light transmittance, high strength and strong durability, and the function here is to isolate the first film layer 21 and the third film layer 23 and protect the micro-nanowire array, if the protection of PMMA is lost, the device is short-circuited, the signal voltage cannot be output, and the carbon fiber part is easily and rapidly lost due to mechanical abrasion.
In addition, materials capable of insulating the first film layer 21 and the third film layer 23 and having a certain toughness may be used as alternatives to the second film layer 22, such as PC (polycarbonate), PET (polyester resin), PSU (polysulfone), PVC (polyvinylchloride), or PDMS (polydimethylsiloxane) film having a certain thickness.
In some embodiments, the second film layer 22 completely blocks the first film layer 21 and the third film layer 23; although the complete blocking of the second thin film layer 22 can play a role in blocking the electric field, it is verified through experiments that if the second thin film layer 22 has a hollow structure, the first thin film layer 21 and the third thin film layer 23 are disconnected, so that the signal voltage cannot be output, and therefore, in order to ensure that the optical signal response generating sheet works normally, the second thin film layer 22 needs to completely block the first thin film layer 21 and the third thin film layer 23.
In some embodiments, the third thin film layer 23 is a silver micro-nanowire layer spin-coated on a side of the second thin film layer 22 remote from the first thin film layer 21.
In addition, the third film layer 23 may be formed by sputtering one or more of gold, platinum, copper or aluminum onto the second film layer 22, or by tightly adhering one or more of a metal foil, a metal fiber or a conductive rubber film onto the second film layer 22.
In some embodiments, the material of the encapsulation layer 10 is a high molecular polymer material, and the encapsulation layer 10 is prepared by fixed die reverse molding or spin coating.
After the optical signal response generating sheet is implanted into a human body, the packaging layer 10 is in direct contact with human body tissues, the biocompatibility of the high polymer material is strong, the stimulation to the human body tissues is small, and the influence of the implanted generating sheet on a patient can be reduced; in addition, the high polymer material is soft and bendable, can be well attached to human tissues of an implantation part, and can reduce the stimulation to the human tissues.
And the packaging layer 10 is prepared through the mode of fixed mould reverse mould and spin coating, on one hand, can guarantee that the packaging layer 10 is relatively less, reduce the influence of electricity generation piece to human tissue, on the other hand can make the packaging layer 10 size, thickness and the shape that prepare in batches the same to increase the uniformity of electricity generation piece, be convenient for the doctor to carry out the operation and implant.
The spin coating mode can effectively control the thickness of the material film and reduce the thickness of the organic material film as much as possible, so that the overall thickness of the optical signal response generating sheet is reduced, the influence of the generating sheet on the human body after being implanted into the human body is reduced, and the biocompatibility is increased.
In some embodiments, the encapsulation layer 10 includes a first encapsulation layer 11 and a second encapsulation layer 12 that are tightly secured to effectively isolate the power generation assembly 20 from human biological tissue.
In some embodiments, the optical signal responsive power generating sheet has an area of 2.25cm2 or less and a thickness of 0.5cm or less; by controlling the volume of the light signal response generating sheet, on one hand, the influence on the human body when the generating sheet is implanted into the human body can be reduced as much as possible, and on the other hand, the generating sheet can be implanted through minimally invasive surgery, so that the surgery burden of a patient is reduced.
The technical features of the above-described embodiments may be arbitrarily combined, and all possible combinations of the technical features in the above-described embodiments are not described for brevity of description, however, as long as there is no contradiction between the combinations of the technical features, they should be considered as the scope of the description.
The above examples illustrate only a few embodiments of the invention, which are described in detail and are not to be construed as limiting the scope of the invention. It should be noted that it will be apparent to those skilled in the art that several variations and modifications can be made without departing from the spirit of the invention, which are all within the scope of the invention. Accordingly, the scope of protection of the present invention is to be determined by the appended claims.