Lubricating layer with hydrogen-loaded complex as well as preparation method and application of lubricating layer

Abstract

The invention relates to the field of medical equipment lubricants, in particular to a lubricating layer with a hydrogen-loaded complex and a preparation method and application of the lubricating layer. The preparation method comprises the following steps: dispersing palladium nanoparticles into deionized water to obtain a palladium nanoparticle solution; hydrogen is introduced into the palladium nanoparticle solution in a bubbling mode for hydrogenation reaction, and palladium hydride particles are obtained; dissolving the polydopamine powder to obtain a polydopamine solution; the polydopamine solution and the palladium hydride particles are subjected to ultrasonic treatment, and a composite coating solution is obtained; spraying the composite coating liquid on the surface of the tracheal catheter cuff to obtain a composite coating; and drying the composite coating to obtain the lubricating layer with the hydrogen-loaded complex. According to the preparation method, palladium hydride nanoparticles can be bonded by using polydopamine, so that the flowability and hydrogen loading capacity of the palladium hydride nanoparticles can be improved, and therefore, active hydrogen can be accurately controlled and continuously generated between a cuff wall and a pressed mucous membrane, and mucous membrane injury caused by an oxidative stress effect under oppression ischemia can be reduced.

Description

Technical Field

[0001] The present application relates to the field of medical device lubricants, and particularly to a lubricating layer having a hydrogen-carrying complex, a preparation method thereof, and an application thereof. Background Art

[0002] General anesthesia with an endotracheal tube (ETT) is still the most common surgical anesthesia method at present. After the ETT cuff is inflated, it can seal the airway for artificial ventilation and prevent the occurrence of regurgitation and aspiration at the same time. With the significant increase in the number of patients requiring emergency tracheal intubation, the ETT cuff plays an irreplaceable role in the establishment of artificial airways. However, establishing an appropriate cuff pressure is challenging. Studies have shown that the capillary venous pressure of the airway mucosa is about 24 cmH 2 O, and the hydrostatic pressure of the mucosal lymphatic vessels is about 7 cmH 2 O. Existing studies have shown that when the mucosa is compressed by more than 35 cmH 2 O, the capillary and lymphatic return of the airway mucosa will be blocked, which makes the airway mucosa in a state of compressive ischemia as Figure 4 shown. Improper establishment of cuff pressure and various factors during surgery will significantly increase the cuff pressure of the tracheal tube, resulting in too high a cuff pressure of the tracheal tube. If the high cuff pressure persists, mucosal damage will occur in a short time under the ischemic state of the airway mucosa, thus causing airway mucosal damage in patients undergoing general anesthesia tracheal intubation. Airway mucosal damage can cause cilia shedding, epithelial cell necrosis, and epithelial cell apoptosis. With the destruction of the epithelial layer of the airway mucosa, too high a cuff pressure will cause postoperative sore throat, and to a certain extent, it will also cause mucosal edema and ulcers, and severely, it will cause postoperative airway stenosis or even fatal tracheal rupture. Paying attention to the damage of cuff pressure to the airway mucosa is an important aspect of airway protection in patients undergoing general anesthesia. Existing investigations have found that more than 80.3% of anesthesiologists will inflate the cuff pressure to 53.3 cmH 2 O. In addition, many factors during surgery, such as changes in the patient's body position and the establishment of artificial pneumoperitoneum, will cause an increase in cuff pressure.

[0003] To reduce the damage to airway mucosa caused by excessive cuff pressure, based on the characteristics that liquid has better buffering effect and more balanced stress conduction than air, normal saline can be used to expand the ETT cuff, or after expanding the cuff with alkalized lidocaine solution, part of the lidocaine will penetrate through the cuff wall to play a mucosal protective role. However, most of these methods buffer the pressure conduction in terms of physical properties, and their buffering effect is limited. With the in-depth research, it is found that the essence of cuff compression-induced mucosal injury is a kind of tissue ischemic injury, and it will suffer from ischemia-reperfusion injury again when perfusion is restored after pressure release. During this injury process, a large amount of hydroxyl radicals (·OH) will be generated, which will induce oxidative stress injury of mucosal cells. And ·OH is mainly generated through a large number of pathways such as the xanthine oxidase metabolic pathway, the "respiratory burst" of neutrophils, and the auto-oxidation increase of catecholamines. A large amount of ·OH will cause the imbalance between tissue oxidation and antioxidant, leading to tissue oxidative stress injury. The free radical activity after this ischemia-reperfusion has the characteristics of being rapid and short-lived. Based on the characteristics of mucosal injury caused by cuff compression, theoretically, using a reducing agent to neutralize ·OH can reduce mucosal cell injury to a certain extent. The applicant's previous research found that dissolving natural antioxidant hydrogen (Hydrogen, H 2 ) in normal saline to expand the ETT cuff. Based on the strong penetration characteristics of hydrogen, hydrogen overflows from the solute and penetrates through the cuff wall to act on the compressed mucosa, so as to Figure 5 play an antioxidant stress effect as shown. Therefore, hydrogen can reduce mucosal injury under high cuff pressure, and the principle of this reduction may be related to reducing the pyroptosis process of compressed mucosal cells.

[0004] Hydrogen is the smallest gaseous element in nature and is a natural antioxidant. At present, the safety of hydrogen for the human body has been confirmed. Hydrogen has a strong antioxidant stress effect. Existing studies have shown that inhaling hydrogen with a volume concentration of 2% can successfully reduce the cerebral infarction area and improve the prognosis in a rat model of stroke. Through in vivo and in vitro studies, it is confirmed that hydrogen has a selective neutralizing effect on the highly damaging reactive oxygen species hydroxyl radical (·OH) and peroxynitrite anion (ONOO -) while having no effect on the physiologically active superoxide anion (O 2 -·) etc. have no neutralizing effect. Therefore, hydrogen is considered to have a selective antioxidant stress effect. Since then, a large number of studies have confirmed the effectiveness of hydrogen intervention in various ischemia-reperfusion injury models. However, hydrogen exists in a gaseous state at room temperature and is slightly soluble in water, with a solubility of only 1.8 ml / 100 ml at room temperature and atmospheric pressure. And existing studies have found that the proportion of hydrogen permeating through the cuff after overflowing from hydrogen-rich saline is limited, and this permeation proportion is generally about 12%, which greatly weakens the probability of hydrogen acting on the compressed mucosa. Therefore, the current technical difficulty of the ETT cuff lies in how to make hydrogen act more effectively on the compressed airway mucosa. And the key to this technical difficulty is how to improve the supply mode of hydrogen and make hydrogen act precisely on the airway mucosa to enhance the mucosal protection effect of hydrogen. Therefore, developing a carrier with hydrogen release ability to slowly and continuously release hydrogen between the cuff wall and the compressed mucosa may be an effective way to break through the current research bottleneck.

[0005] With the development of hydrogen in the medical field, the research on hydrogen production methods has also emerged. Currently, the most commonly used method is to use professional equipment to electrolyze water to produce hydrogen, but this method is limited by energy consumption and related equipment and has higher requirements for safety factors. Existing studies have shown that noble metal particles have perfect hydrogen storage capacity. Especially noble metal nanoparticles palladium (Pb), which is an important industrial hydrogenation catalyst. It can adsorb hydrogen molecules on the surface to form palladium hydride (PdH) nanoparticles (the molar ratio of H:Pd is 0.2:1), which is a good hydrogen storage device. In addition, palladium hydride can dissociate into single hydrogen atoms, and the dissociated hydrogen atoms can even combine into the lattice of Pd nanocrystals; under the catalytic action of Pd nanoparticles, the dissociated hydrogen atoms existing in the form of ·H or / and H- on the surface of palladium hydride have significantly higher reduction ability. These dissociated hydrogen atoms are beneficial to the hydrogenation of oxidation products, especially the scavenging of highly oxidized ·OH. PdH has a unique ·OH-triggering property, specifically releasing highly reducing hydrogen atoms instead of bubble-like hydrogen molecules in the presence of ·OH, as shown in the following chemical formula:

[0006] Pd + H 2 →PdH x；

[0007] PdH + ·OH → Pd + H 2 O + (·H or H - );

[0008] In existing research, ·OH-triggered PdH has been applied to the study of neurodegenerative diseases, reducing central neuroinflammation by selectively scavenging ·OH in the brain. Then, based on the generation of a large amount of ·OH during the process of mucosal compression injury, it is speculated that PdH can be used in the lubricating coating of the cuff, and PdH can be triggered by ·OH and release active hydrogen atoms to precisely consume hydroxyl radicals between the cuff wall and the mucosa. In addition, these active hydrogen atoms can further selectively neutralize other reactive oxygen components. However, the hydrogen-carrying capacity of current single Pd nanoparticles is limited, so it is necessary to further increase the hydrogen content of Pd nanoparticles. Summary of the Invention

[0009] This application provides a lubricating layer with a hydrogen-carrying complex, its preparation method and application, to solve the following technical problem: how to increase the hydrogen content of Pd nanoparticles.

[0010] In a first aspect, an embodiment of this application provides a preparation method of a lubricating layer with a hydrogen-carrying complex, and the preparation method includes:

[0011] Disperse palladium nanoparticles into deionized water to obtain a palladium nanoparticle solution;

[0012] Introduce hydrogen into the palladium nanoparticle solution in a bubbling manner for a hydrogenation reaction to obtain hydrogenated palladium particles;

[0013] Dissolve polydopamine powder to obtain a polydopamine solution;

[0014] Ultrasonically treat the polydopamine solution and the hydrogenated palladium particles to obtain a composite coating solution;

[0015] Spray the composite coating solution on the surface of the tracheal tube cuff to obtain a composite coating;

[0016] Dry the composite coating to obtain a lubricating layer with a hydrogen-carrying complex.

[0017] Optionally, the mass m1 of the polydopamine solute in the polydopamine solution and the mass m2 of the hydrogenated palladium particles satisfy the relationship: m1:m2 ≥ 20:1.

[0018] Optionally, the frequency of the ultrasonic treatment is 35 kHz to 45 kHz, and the time of the ultrasonic treatment is 30 min to 60 min.

[0019] Optionally, the spraying pressure is 0.2 MPa to 0.5 MPa, the spraying spray distance is 5 cm to 10 cm, and the number of spraying times is 2 to 3 times.

[0020] Optionally, the diameter of the palladium nanoparticles is 5 nm to 10 nm; and / or

[0021] The particle size of the polydopamine powder is 50 nm to 200 nm; and / or

[0022] The mass concentration of the composite coating solution is 0.5 mg / mL to 2 mg / mL.

[0023] Optionally, the method for preparing the polydopamine powder includes:

[0024] Dissolve dopamine hydrochloride in a tris(hydroxymethyl)aminomethane hydrochloride buffer solution to obtain a hydrochloric acid solution of dopamine;

[0025] Perform an auto-oxidation reaction on the hydrochloric acid solution of dopamine under an alkaline environment, so that the dopamine undergoes auto-oxidative polymerization to obtain polydopamine nanoparticles;

[0026] Freeze-dry the polydopamine nanoparticles to obtain polydopamine powder.

[0027] Optionally, the temperature of the auto-oxidation reaction is 23°C to 27°C, the time of the auto-oxidation reaction is 6 h to 24 h, and the pH value of the auto-oxidation reaction is 7 to 9.

[0028] Optionally, the auto-oxidation reaction includes performing the auto-oxidation reaction under stirring conditions, and the rotation speed of the stirring is 200 rpm to 500 rpm; and / or

[0029] The mass concentration of the hydrochloric acid solution of dopamine is 0.5 mg / mL to 2 mg / mL.

[0030] In a second aspect, the present application provides a lubricating layer having a hydrogen-carrying complex, and the lubricating layer is prepared by the preparation method described in the first aspect.

[0031] In a third aspect, the present application provides an endotracheal tube cuff, and the surface of the cuff has the lubricating layer described in the second aspect.

[0032] The above technical solutions provided by the embodiments of the present application have the following advantages compared with the prior art:

[0033] A preparation method of a lubricating layer with a hydrogen-carrying complex provided by an embodiment of the present application. In this preparation method, palladium nanoparticles and hydrogen are used as raw materials, and small granular palladium hydride particles can be synthesized by the method of hydrogen bubbling, which enables the palladium hydride particles to have more surface binding sites, effectively increasing the hydrogen-carrying capacity of the palladium hydride particles. Additionally, ultrasonic treatment is performed on a polydopamine solution and palladium hydride particles, and through ultrasonic treatment, the polydopamine and palladium hydride particles are fully mixed. Based on the adhesiveness and reducibility of polydopamine, the damping property on the surface of the palladium hydride particles and the ability of the palladium hydride particles to bind hydrogen atoms can be effectively reduced, thereby improving the fluidity and hydrogen-carrying capacity of the palladium hydride particles. Based on the fluidity and hydrogen-carrying capacity of the composite coating liquid, a lubricating layer with a sufficient thickness can be formed on the surface of the tracheal tube cuff through spraying treatment and drying, so as to accurately control and continuously generate active hydrogen between the cuff wall and the compressed mucosa, thereby reducing mucosal damage caused by oxidative stress effects under compression ischemia. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] The accompanying drawings herein are incorporated into the specification and form a part of this specification, showing embodiments consistent with the present application, and are used together with the specification to explain the principles of the present application.

[0035] To more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the accompanying drawings required for use in the description of the embodiments or the prior art. Obviously, for those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0036] Figure 1 It is a schematic flow chart of a preparation method of a lubricating layer with a hydrogen-carrying complex provided by an embodiment of the present application;

[0037] Figure 2 It is a detailed schematic flow chart of a preparation method of a lubricating layer with a hydrogen-carrying complex provided by an embodiment of the present application;

[0038] Figure 3 It is a schematic principle diagram of a preparation method of a lubricating layer with a hydrogen-carrying complex provided by an embodiment of the present application;

[0039] Figure 4 It is a schematic principle diagram of mucosal damage caused by excessive cuff pressure provided by the present application;

[0040] Figure 5 It is a schematic principle diagram of the potential mechanism of using hydrogen-rich saline to expand the cuff to protect airway mucosa provided by the present application;

[0041] Figure 6 It is a schematic concept diagram of using PdH for the tracheal tube lubricating coating to protect airway mucosa provided by the present application;

[0042] Figure 7 Transmission electron microscopy (TEM) detection results of Pd particles and PdH particles and hydrogen release capacity results of PdH particles provided in Example 1 of this application; among them, Figure 7 A is the TEM detection result of Pd particles, and the scale bar is 50 nm; Figure 7 B is the TEM detection result of PdH particles, and the scale bar is 50 nm; Figure 7 C is the hydrogen release capacity curve result of PdH particles;

[0043] Figure 8 Comparison result diagrams of the lubricating layer after forming under a magnifying glass for 0.5 h and 6 h provided in Example 2 of this application; among them, the tracheal tube cuff with the loaded coating is within the white frame line;

[0044] Figure 9 Results diagrams of the toxicity of different doses of the lubricating layer to cells and the scavenging ability of reactive oxygen species provided in Example 2 of this application; among them, Figure 9 A is the toxicity result diagram of different doses of the lubricating layer to cells; Figure 9 B is the scavenging ability result diagram of different doses of the lubricating layer to reactive oxygen species in cells;

[0045] Figure 10 Comparison result diagrams of airway mucosal injury between the tracheal tube cuff provided in Example 2 of this application and the tracheal tube cuff with a traditional lubricating coating; among them, Figure 10 A is a typical hematoxylin and eosin staining image of the airway mucosa by the tracheal tube cuff with a traditional lubricating coating, the scale bar is 100 μm, the black arrow indicates vascular congestion, the red arrow indicates epithelial injury, and the blue arrow indicates inflammatory exudation; Figure 10 B is the TEM result diagram of the airway mucosa by the tracheal tube cuff provided in Example 2, and the scale bar is 2 μm. Detailed implementation manners

[0046] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions in the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings in the embodiments of this application. Obviously, the described embodiments are some but not all of the embodiments of this application. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of this application without creative efforts shall fall within the protection scope of this application.

[0047] Various embodiments of the present application may exist in the form of a range; it should be understood that the description in the form of a range is only for convenience and brevity, and should not be construed as a rigid limitation on the scope of the present application; therefore, it should be considered that the described range description has specifically disclosed all possible sub-ranges and single values within that range; for example, it should be considered that the range description from 1 to 6 has specifically disclosed sub-ranges such as from 1 to 3, from 1 to 4, from 1 to 5, from 2 to 4, from 2 to 6, from 3 to 6, etc., and single numbers within the range, such as 1, 2, 3, 4, 5, and 6, and this applies regardless of the range; in addition, whenever a numerical range is indicated herein, it means including any cited number (fraction or integer) within the indicated range.

[0048] As used herein, the term "comprising" and the like means "including but not limited to". Relative terms such as "first" and "second" are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. "And / or" describes the associated relationship of associated objects and indicates that three relationships may exist. For example, A and / or B may mean: A exists alone, A and B exist simultaneously, and B exists alone; where A and B may be singular or plural. "At least one" means one or more, and "a plurality" means two or more; "at least one kind", "at least one of the following items (pieces)" or similar expressions refer to any combination of these items, including any combination of single items (pieces) or plural items (pieces); for example, "at least one of a, b, or c", or, "at least one of a, b, and c" can both represent: a, b, c, a - b (i.e., a and b), a - c, b - c, or a - b - c, where a, b, and c can be single or multiple respectively. The "parts representation method" such as weight parts, mass parts, etc. represents the proportional relationship between each component. In the proportional relationships involved herein, the parameters that need to be described by proportion should be understood as the antecedents of the proportion formula in the order of description, and the proportional numbers should be understood as the consequents of the proportion formula. For example, if the mass ratio of substance A, substance B, and substance C is 1:2:3, then substance A, substance B, and substance C should correspond one by one with the proportional numbers in the proportion formula in the order of description, that is, the mass of substance A: the mass of substance B: the mass of substance C = 1:2:3.

[0049] Unless otherwise specifically stated, various raw materials, reagents, instruments, equipment, etc. used herein can be obtained through market purchase or can be prepared by existing methods.

[0050] It should be noted that based on the prior art described in the background art, the inventor found that: using PdH in the lubricating coating of tracheal catheters may protect the airway mucosa, and its overall concept is as Figure 6As shown. However, the hydrogen storage capacity of current nano Pd metal monomers is limited. Therefore, it is necessary to improve the hydrogen storage capacity of nano Pd metal monomers at present. In addition, at present, the tracheal catheter coating of airway mucosa mainly uses a lubricating coating prepared with local anesthetics such as tetracaine or lidocaine. This lubricating coating is mainly based on the analgesic effect of local anesthetics to reduce discomfort symptoms such as throat pain caused by mucosal damage during patient intubation. The preparation method of this lubricating coating is to mix lidocaine with a mass concentration of 2% or tetracaine with a mass concentration of 1% in liquid paraffin or lubricating mucilage to prepare a lubricant, or directly use dyclonine mucilage as a lubricant, and evenly apply it on the surface of the ETT cuff before use to form a lubricating layer. This lubricating layer only reduces the subjective discomfort of patients through the local anesthetic effect of anesthetics, only alleviates the related pain and discomfort symptoms after mucosal damage, and cannot fundamentally solve the occurrence of patients' discomfort, nor can it effectively prevent airway mucosal damage.

[0051] The inventors found through a large number of creative experiments that: nano polydopamine materials not only have high adhesion performance. When using polydopamine (PDA) to evenly load Pd particles after hydrogen storage onto the tracheal catheter cuff wall, it can effectively increase the autocatalytic efficiency of Pd (as Figure 3 shown). Based on this discovery, using the PDA-Pd hydrogen storage system to prepare the lubricating coating of the ETT cuff can continuously produce active hydrogen between the cuff wall and the compressed mucosa, so as to reduce mucosal damage caused by oxidative stress effects under compression ischemia. Further introducing mesoporous silica nanoparticles (MSN) into the PDA-Pd hydrogen storage system to form a hydrogen storage complex, the ETT coating prepared by it can precisely and controllably continuously produce active hydrogen between the cuff wall and the compressed mucosa. Therefore, the ETT coating prepared by this hydrogen storage complex can provide a new option for mucosal protection of tracheal intubation patients and reduce the occurrence of tracheal intubation-related complications; at the same time, the application of this hydrogen storage complex is also an innovative measure to expand the hydrogen energy industry into the field of medical health.

[0052] Figure 1 Exemplarily shows a schematic flow chart of a preparation method of a lubricating layer with a hydrogen storage complex provided by an embodiment of the present application;

[0053] Figure 3 Exemplarily shows a schematic principle diagram of a preparation method of a lubricating layer with a hydrogen storage complex provided by an embodiment of the present application;

[0054] As Figure 1 and Figure 3 shown, a preparation method of a lubricating layer with a hydrogen storage complex provided by an embodiment of the present application, the preparation method includes:

[0055] S1. Disperse palladium nanoparticles into deionized water to obtain a palladium nanoparticle solution;

[0056] S2. Introduce hydrogen into the palladium nanoparticle solution in a bubbling manner for a hydrogenation reaction to obtain palladium hydride particles;

[0057] S3. Dissolve polydopamine powder to obtain a polydopamine solution;

[0058] S4. Ultrasonically treat the polydopamine solution and the palladium hydride particles to obtain a composite coating solution;

[0059] S5. Spray the composite coating solution onto the surface of the tracheal tube cuff to obtain a composite coating;

[0060] S6. Dry the composite coating to obtain a lubricating layer with a hydrogen-carrying complex.

[0061] It should be noted that before use, the tracheal tube cuff can be thoroughly cleaned with isopropanol or deionized water to remove impurities and oil stains on the surface of the tracheal tube cuff, and then it can be further cleaned using an ultrasonic cleaner (ultrasonic frequency is 40 kHz, working time is 10 min - 15 min).

[0062] It should be noted that the palladium nanoparticles can be synthesized through a simple redox route.

[0063] It should be noted that the embodiment of the present application provides a preparation method for a lubricating layer with a hydrogen-carrying complex. This preparation method has significant technical advantages in the research of the cross-field of materials science and biomedical engineering and can effectively solve some problems in related applications of the prior art. The specific principle is as follows:

[0064] During the preparation process, palladium nanoparticles and hydrogen are first selected as key raw materials. In a unique way of hydrogen bubbling, hydrogen is slowly and continuously introduced into the reaction system containing palladium nanoparticles. During this process, hydrogen molecules come into full contact with palladium nanoparticles and react, thus synthesizing small particles of palladium hydride. Compared with those prepared by traditional methods, the palladium hydride particles synthesized through hydrogen bubbling have extremely obvious structural advantages. Their particle size is smaller, which increases the specific surface area and thus has more surface binding sites. These abundant surface binding sites can effectively increase the hydrogen-carrying capacity of the palladium hydride particles, laying a good foundation for subsequent applications.

[0065] The next step is equally crucial. Mix the polydopamine solution with the prepared palladium hydride particles above and perform ultrasonic treatment. Under the action of ultrasound, the high-frequency vibration of ultrasonic waves generates powerful energy, prompting the full mixing of polydopamine and palladium hydride particles. Polydopamine has unique chemical properties. It has adhesiveness and can bind different substances together; it also has reducibility, and this reducibility can effectively react with certain chemical groups on the surface of palladium hydride particles. Through these two characteristics, polydopamine can reduce the damping on the surface of palladium hydride particles, weaken the interaction between palladium hydride particles, and thus improve the fluidity of palladium hydride particles. At the same time, polydopamine can also reduce the ability of palladium hydride particles to bind hydrogen atoms, making the binding of hydrogen atoms on the particle surface more stable and easier to release, further increasing the hydrogen-carrying capacity of palladium hydride particles.

[0066] Based on the good fluidity and high hydrogen-carrying capacity of the composite coating liquid after the above treatment, the composite coating liquid is subsequently sprayed evenly on the surface of the tracheal tube cuff by means of spraying treatment. During the spraying process, the spraying amount and range can be precisely controlled to ensure uniform distribution of the coating. After spraying, through drying treatment, the solvent in the composite coating liquid volatilizes, thereby forming a lubricating layer with sufficient thickness on the surface of the tracheal tube cuff. This lubricating layer can precisely control and continuously generate active hydrogen between the cuff wall and the compressed mucosa. In the human physiological environment, this lubricating layer will generate a large amount of active hydrogen, and these active hydrogen can effectively neutralize the harmful free radicals generated by oxidative stress, reduce the mucosal damage caused by the oxidative stress effect under compression ischemia, and provide better protection for the health of patients.

[0067] In some alternative embodiments, the mass m1 of the polydopamine solute in the polydopamine solution and the mass m2 of the palladium hydride particles satisfy the relationship: m1:m2 ≥ 20:1.

[0068] In these embodiments, the mass m1 of the polydopamine solute in the polydopamine solution and the mass m2 of the palladium hydride particles can satisfy the relationship: m1:m2 ≥ 20:1, such that the polydopamine solute in the polydopamine solution is in an excessive state compared to the palladium hydride particles, so as to prompt the full mixing of polydopamine and palladium hydride particles, thereby effectively reducing the damping on the surface of palladium hydride particles and the ability of palladium hydride particles to bind hydrogen atoms, and improving the fluidity and hydrogen-carrying capacity of palladium hydride particles.

[0069] In some alternative embodiments, the frequency of the ultrasonic treatment is 35 kHz to 45 kHz, and the time of the ultrasonic treatment is 30 min to 60 min.

[0070] In these embodiments, the frequency of the ultrasonic treatment can be 35 kHz to 45 kHz, and the time of the ultrasonic treatment can be 30 min to 60 min, so that polydopamine and palladium hydride particles are fully mixed, thereby effectively reducing the damping property on the surface of the palladium hydride particles and the ability of the palladium hydride particles to bind hydrogen atoms, in order to improve the fluidity and hydrogen storage capacity of the palladium hydride particles.

[0071] The frequency of the ultrasonic treatment can be 35 kHz, 36 kHz, 37 kHz, 38 kHz, 39 kHz, 40 kHz, 41 kHz, 42 kHz, 43 kHz, 44 kHz or 45 kHz.

[0072] The time of the ultrasonic treatment can be 30 min, 35 min, 40 min, 45 min, 50 min, 55 min or 60 min.

[0073] In some alternative embodiments, the spraying pressure is 0.2 MPa to 0.5 MPa, the spraying spray distance is 5 cm to 10 cm, and the number of spraying times is 2 to 3 times.

[0074] In these embodiments, the spraying pressure can be 0.2 MPa to 0.5 MPa, the spraying spray distance can be 5 cm to 10 cm, and the number of spraying times can be 2 to 3 times, so that the composite coating liquid is evenly spread on the surface of the tracheal tube cuff, and a uniform lubricating layer can be formed after drying.

[0075] The spraying pressure can be 0.2 MPa, 0.3 MPa, 0.4 MPa or 0.5 MPa.

[0076] The spraying spray distance can be 5 cm, 6 cm, 7 cm, 8 cm, 9 cm or 10 cm.

[0077] The number of spraying times can be 2 times or 3 times.

[0078] In some alternative embodiments, the diameter of the palladium nanoparticles is 5 nm to 10 nm; and / or

[0079] the particle size of the polydopamine powder is 50 nm to 200 nm; and / or

[0080] the mass concentration of the composite coating liquid is 0.5 mg / mL to 2 mg / mL.

[0081] In these embodiments, the diameter of the palladium nanoparticles can be 5 nm to 10 nm, so that the palladium nanoparticles have a sufficient specific surface area to facilitate the adsorption of a sufficient number of hydrogen atoms by the palladium nanoparticles during the subsequent hydrogenation reaction, thereby increasing the hydrogen storage capacity of palladium hydride; in addition, the particle size of the polydopamine powder can be 50 nm to 200 nm, so that the polydopamine and palladium hydride particles are fully mixed, thereby effectively reducing the damping property on the surface of the palladium hydride particles and the ability of the palladium hydride particles to bind hydrogen atoms, and increasing the fluidity and hydrogen storage capacity of the palladium hydride particles; furthermore, the mass concentration of the composite coating solution can be 0.5 mg / mL to 2 mg / mL, so that there are sufficient polydopamine-palladium hydride particles in the composite coating solution to facilitate the formation of a lubricating layer with a sufficient thickness in the subsequent process.

[0082] The diameter of the palladium nanoparticles can be 5 nm, 6 nm, 7 nm, 8 nm, 9 nm or 10 nm.

[0083] The particle size of the polydopamine powder can be 50 nm, 60 nm, 70 nm, 80 nm, 90 nm, 100 nm, 110 nm, 120 nm, 130 nm, 140 nm, 150 nm, 160 nm, 170 nm, 180 nm, 190 nm or 200 nm.

[0084] The mass concentration of the composite coating solution can be 0.5 mg / mL, 0.6 mg / mL, 0.7 mg / mL, 0.8 mg / mL, 0.9 mg / mL, 1.0 mg / mL, 1.1 mg / mL, 1.2 mg / mL, 1.3 mg / mL, 1.4 mg / mL, 1.5 mg / mL, 1.6 mg / mL, 1.7 mg / mL, 1.8 mg / mL, 1.9 mg / mL or 2.0 mg / mL.

[0085] Figure 2 Exemplarily, a detailed flowchart showing the preparation method of a lubricating layer with a hydrogen storage complex provided by an embodiment of the present application is shown;

[0086] In some alternative embodiments, as Figure 2 shown, the preparation method of the polydopamine powder includes:

[0087] S401. Dissolve dopamine hydrochloride in a tris(hydroxymethyl)aminomethane hydrochloride buffer solution to obtain a hydrochloric acid solution of dopamine.

[0088] S402. Perform an auto-oxidation reaction on the hydrochloric acid solution of dopamine in an alkaline environment, so that the dopamine undergoes auto-oxidative polymerization to obtain polydopamine nanoparticles.

[0089] S403. Freeze-dry the polydopamine nanoparticles to obtain polydopamine powder.

[0090] In these embodiments, dopamine hydrochloride is first used as a raw material to dissolve and form a hydrochloric acid solution of dopamine. Then, in an alkaline environment, the hydrochloric acid solution of dopamine undergoes an auto-oxidation reaction, and through the auto-oxidation reaction, dopamine can polymerize itself to form a large amount of polydopamine. Subsequently, through freeze-drying, the moisture of the polydopamine can be fully removed to obtain pure polydopamine powder.

[0091] In some alternative embodiments, the temperature of the auto-oxidation reaction is 23°C to 27°C, the time of the auto-oxidation reaction is 6h to 24h, and the pH value of the auto-oxidation reaction is 7 to 9.

[0092] In these embodiments, the temperature of the auto-oxidation reaction can be 23°C to 27°C, the time of the auto-oxidation reaction can be 6h to 24h, and the pH value of the auto-oxidation reaction can be 7 to 9, so that there is sufficient temperature, time, and appropriate pH value in the auto-oxidation polymerization stage of dopamine, and thus a large amount of polydopamine can be obtained.

[0093] The temperature of the auto-oxidation reaction can be 23°C, 24°C, 25°C, 26°C, or 27°C.

[0094] The time of the auto-oxidation reaction can be 6h, 8h, 10h, 12h, 14h, 16h, 18h, 20h, 22h, or 24h.

[0095] The pH value of the auto-oxidation reaction can be 7, or 8, or 9.

[0096] In some alternative embodiments, the auto-oxidation reaction includes performing the auto-oxidation reaction under stirring conditions, and the rotation speed of the stirring is 200 rpm to 500 rpm; and / or

[0097] The mass concentration of the hydrochloric acid solution of dopamine is 0.5 mg / mL to 2 mg / mL.

[0098] In these embodiments, the auto-oxidation reaction can include performing the auto-oxidation reaction under stirring conditions, and the rotation speed of the stirring can be 200 rpm to 500 rpm, so that the polydopamine and palladium hydride particles are fully mixed, thereby effectively reducing the damping property on the surface of the palladium hydride particles and the ability of the palladium hydride particles to bind hydrogen atoms, to improve the fluidity and hydrogen-carrying capacity of the palladium hydride particles; in addition, the mass concentration of the hydrochloric acid solution of dopamine can be 0.5 mg / mL to 2 mg / mL, so that the hydrochloric acid solution of dopamine has a sufficient amount of dopamine components, and the sufficient amount of dopamine components can effectively undergo an auto-oxidation reaction and obtain a large amount of polydopamine components.

[0099] Based on a general inventive concept, an embodiment of the present application provides a lubricating layer having a hydrogen-carrying complex, and the lubricating layer is prepared by the preparation method.

[0100] This lubricating layer is realized based on the above preparation method. The specific steps of this preparation method can refer to the above embodiments. Since this lubricating layer adopts some or all of the technical solutions of the above embodiments, it at least has all the beneficial effects brought by the technical solutions of the above embodiments, and will not be elaborated one by one here.

[0101] Based on a general inventive concept, an embodiment of the present application provides a cuff for an endotracheal tube, and the surface of the cuff has the lubricating layer.

[0102] This cuff of the endotracheal tube is realized based on the above lubricating layer. The specific composition and source of this lubricating layer can refer to the above embodiments. Since this cuff of the endotracheal tube adopts some or all of the technical solutions of the above embodiments, it at least has all the beneficial effects brought by the technical solutions of the above embodiments, and will not be elaborated one by one here.

[0103] The present application will be further described below in conjunction with specific embodiments. For the experimental methods without specific conditions indicated in the following embodiments, they are usually measured according to national standards / industry standards; if there are no corresponding national standards / industry standards, they are carried out according to general international standards, conventional conditions or the conditions recommended by the manufacturer.

[0104] Example 1

[0105] As Figure 2 shown, a preparation method of a lubricating layer having a hydrogen-carrying complex includes:

[0106] S1. Dispersing palladium nanoparticles into deionized water to obtain a palladium nanoparticle solution;

[0107] S2. Introducing hydrogen into the palladium nanoparticle solution in a bubbling manner for a hydrogenation reaction to obtain palladium hydride particles;

[0108] S3. Dissolving polydopamine powder to obtain a polydopamine solution;

[0109] S401. Dissolving dopamine hydrochloride in a tris(hydroxymethyl)aminomethane hydrochloride buffer solution to obtain a hydrochloric acid solution of dopamine;

[0110] S402. Performing an auto-oxidation reaction on the hydrochloric acid solution of dopamine in an alkaline environment to cause auto-oxidative polymerization of dopamine to obtain polydopamine nanoparticles;

[0111] S403. Freeze-drying the polydopamine nanoparticles to obtain polydopamine powder;

[0112] S4. Ultrasonically treat the polydopamine solution and palladium hydride particles to obtain a composite coating solution;

[0113] S5. Spray the composite coating solution on the surface of the tracheal tube cuff to obtain a composite coating;

[0114] S6. Dry the composite coating to obtain a lubricating layer with a hydrogen-carrying complex. The specific steps are as follows:

[0115] 1. Preparation of nano-palladium particles. Synthesize Pd nano-particles through a simple redox route. The specific steps include:

[0116] (1) First, prepare a mixed aqueous solution of 106.4 mg of vinylpyrrolidone solution (PVP), 60 mg of acrylic acid solution (AA), 301 mg of KBr, and 56.3 mg of Na 2 PdCl 4 . Then, take 11 mL of the mixed aqueous solution and magnetically stir and heat it in an oil bath at 80 °C for 3 h. Then cool the mixed aqueous solution to room temperature. Then use an Amcon ultrafiltration tube (MWCO is 100 kDa, and the micropores are 20 nm) to collect and purify the mixed aqueous solution, and wash the Pd nano-particles three times to obtain Pd nano-particles (the diameter of the Pd nano-particles is 5 nm to 10 nm).

[0117] (2) Disperse the obtained Pd nano-particles in 10 mL of deionized water and store them in the dark for subsequent use to obtain a palladium nano-particle solution.

[0118] (3) Pour the palladium nano-particle solution (2 mL, mass concentration 2 mg / mL) into a 20 mL vial. At the same time, bubble the hydrogen generated by a hydrogen generator into the palladium nano-particle solution to hydrogenate the palladium nano-particles. Stop hydrogenation bubbling after 15 min to obtain PdH nano-particles. Then seal the constructed PdH nano-particles and store them in the dark for subsequent use.

[0119] 2. Preparation of polydopamine (PDA)

[0120] (1) Raw material preparation: Dopamine hydrochloride (DA·HCl): purity ≥ 98%, commonly used in biomaterial research; Tris [Tris(hydroxymethyl)aminomethane]: analytical pure (≥ 99%), used to prepare buffer solutions. Deionized water (DI Water): resistivity ≥ 18.2 MΩ·cm to ensure the purity of the experimental system. Ammonia water (optional, used to adjust pH): mass concentration 25% - 28%, experimental grade.

[0121] 2. Experimental equipment: magnetic stirrer (with temperature control function); ultrasonic cleaner (optional, for cleaning substrate materials); pH meter (accuracy of 0.01); glass beakers or polytetrafluoroethylene beakers (100 mL and 250 mL specifications respectively); vacuum filtration device (optional, for collecting precipitated PDA particles); freeze dryer (optional, for obtaining dry PDA powder)

[0122] 3. PDA preparation process

[0123] (1) Prepare Tris-HCl buffer solution:

[0124] 1) Add 900 mL of deionized water to a beaker, place a magnetic stir bar, and slowly add 1.211 g of Tris (target concentration of 10 mM) while stirring.

[0125] 2) Use concentrated hydrochloric acid (HCl) or ammonia water to adjust the pH of the solution in the beaker to 8.5 (the pH value for common PDA synthesis).

[0126] 3) Finally, make up to 1 L and stir evenly for standby.

[0127] (2) Dissolve dopamine hydrochloride:

[0128] Weigh 200 mg of dopamine hydrochloride (DA·HCl) and dissolve it in 100 mL of the prepared Tris-HCl buffer solution to make its concentration 2 mg / mL (the molar concentration of this Tris-HCl buffer solution ≈ 10.5 mM); then stir rapidly to ensure complete dissolution of dopamine hydrochloride, and the system becomes a colorless or light yellow transparent liquid (DA·HCl).

[0129] (3) Conduct self-oxidation reaction:

[0130] Stirring conditions: At room temperature (25°C ± 2°C), use magnetic stirring (200 rpm - 500 rpm) for uniform mixing;

[0131] Reaction time: 6 h - 24 h (usually the color of the system is the darkest at 12 h, and the most PDA particles are generated).

[0132] Under alkaline conditions, dopamine undergoes oxidation-polymerization to form black PDA nanoparticles or films by itself, and the color of the solution gradually changes to dark brown or black.

[0133] (4) Collect PDA particles

[0134] After the reaction is completed, PDA particles can be collected by centrifugation (rotation speed of 10000 rpm, time of 15 min) or vacuum filtration (using a filter membrane with a pore size of 0.22 μm).

[0135] Wash with deionized water 2 to 3 times to remove unreacted precursors.

[0136] (5) Freeze-drying:

[0137] If solid PDA powder is needed, the sample can be frozen at -80 °C for 12 h and then freeze-dried at -50 °C for 48 h to obtain dry PDA powder.

[0138] 4. Key influencing factors and optimization:

[0139] Effect of pH: PDA can be synthesized at a pH of 7 - 9 for the autoxidation reaction, but the autoxidation reaction is most stable and the PDA yield is high at a pH of 8.5.

[0140] Effect of temperature: The conditions for the autoxidation reaction based on room temperature (25 °C) are relatively mild; although the autoxidation reaction can be accelerated at temperatures above 40 °C, it is easy to cause aggregation of PDA particles.

[0141] Stirring speed: Appropriate stirring (200 rpm - 50 rpm) helps the uniform formation of particles, but too fast stirring speed may cause aggregation and precipitation of PDA.

[0142] Precursor concentration: PDA can be formed with a mass concentration of DA·HCl of 0.5 mg / mL - 2 mg / mL, and the higher the mass concentration, the larger the diameter of the formed PDA particles (however, it is necessary to control the particle size of PDA to 50 nm - 200 nm to facilitate subsequent reactions).

[0143] Based on the solution oxidation method, dopamine autoxidation reaction can be promoted to generate PDA in a Tris-HCl buffer solution with a pH of 8.5. This solution oxidation method has the characteristics of simple operation and mild reaction, and can be applied to nanoparticle synthesis, biomaterial modification or surface coating. The final PDA product can be extracted and preserved by methods such as centrifugation, filtration, and freeze-drying.

[0144] Example 2

[0145] On the basis of the content disclosed in Example 1, the following further operations are carried out:

[0146] 5. Preparation process of polydopamine (PDA)-Pd coating:

[0147] (1) Cleaning of the tracheal tube cuff:

[0148] Thoroughly clean the surface of the tracheal tube cuff with isopropyl alcohol or deionized water to remove surface impurities and oil. An ultrasonic cleaner (ultrasonic frequency of 40 kHz, cleaning time of 10 min to 15 min) can be used to further ensure that there is no dust or grease on the surface. After cleaning, rinse repeatedly with deionized water and dry the tracheal tube by air drying or using a dust-free cloth.

[0149] (2) Palladium hydride particle dispersion:

[0150] Mix the hydrogenated palladium hydride nanoparticles (PdH) that have been hydrogenated with the prepared polydopamine solution at a mass ratio of 20:1. Use an ultrasonic processor (frequency of 40 kHz, power of 200 W) to disperse the PdH nanoparticles in the polydopamine solution to ensure their uniform distribution in the polydopamine solution and avoid agglomeration of PdH nanoparticles. The ultrasonic treatment time is 30 min to 60 min until the PdH particles are completely dispersed and there is no obvious precipitation in the solution.

[0151] (3) Coating preparation:

[0152] Mix the prepared polydopamine solution and the dispersion of palladium hydride evenly according to the mass ratio of polydopamine to PdH particles of 20:1 to finally obtain a composite coating solution. The mass concentration of the composite solution should be controlled within the range of 0.5 mg / mL to 2 mg / mL to ensure the uniformity and thickness of the lubricating coating.

[0153] (4) Spraying operation:

[0154] Load the composite coating solution into a spray gun or atomizing nozzle, and adjust the appropriate spray pressure to 0.2 MPa to 0.5 MPa and the spray distance to 5 cm to 10 cm. Use spraying technology to evenly spray the composite coating solution on the surface of the tracheal tube cuff. Keep the spraying equipment stable during coating to ensure the uniformity of each layer of the coating. The coating thickness can be controlled by the number of spraying times, generally spraying 2 to 3 times to ensure that the coating reaches the required thickness (0.5 mm).

[0155] (5) Coating curing:

[0156] After spraying, place the coated tracheal tube cuff at room temperature for natural drying or dry it in an oven at 60 °C for 2 h to 4 h to ensure that the polydopamine coating and palladium particles are firmly attached to the surface of the catheter. Low-temperature curing (for example, curing at 50 °C for 12 h) can be carried out when necessary to enhance the stability of the coating.

[0157] Related experiments and effect data:

[0158] 1. Perform transmission electron microscopy detection on the Pd particles and PdH particles prepared in Example 1, and simultaneously detect the hydrogen release ability of the PdH particles. The results are asFigure 7 As shown in Figure 7 , it can be seen that the preparation method of a lubricating layer with a hydrogen-carrying complex provided by the embodiment of the present application has a relatively uniform distribution of PdH particles and a high hydrogen-carrying capacity of PdH particles.

[0159] 2. Observe the morphological changes of the lubricating layer prepared in Example 2 under a magnifying glass. The comparison results after 0.5 h and 6 h of the formation of the lubricating layer are as Figure 8 shown in Figure 8 . It can be seen that the preparation method of a lubricating layer with a hydrogen-carrying complex provided by the embodiment of the present application has the lubricating layer prepared by this preparation method sprayed on the surface of the tracheal tube cuff and has not changed its morphology for 6 h, indicating that the lubricating layer has good stability.

[0160] 3. Scrape a part of the lubricating layer prepared in Example 2, and add this part of the lubricating layer to the cell culture medium in different doses for culture, and at the same time detect the scavenging ability of reactive oxygen species in the culture medium. The results are as Figure 9 shown in Figure 9 . It can be seen that a lubricating layer with a hydrogen-carrying complex provided by the embodiment of the present application has a scavenging ability of more than 70% for reactive oxygen species at different doses.

[0161] 4. Respectively conduct actual animal experiments on the tracheal tube cuff with a lubricating layer obtained in Example 2 and the traditional tracheal tube cuff using an anesthetic agent as the lubricating layer (preparing a lubricant by mixing lidocaine with a mass concentration of 2% or tetracaine with a mass concentration of 1% in liquid paraffin or lubricating mucilage, and then coating it on the surface of the tracheal tube cuff to form a lubricating coating): respectively insert the tracheal tube cuff with a lubricating layer of the present application and the traditional tracheal tube cuff into the airway mucosa of an animal model (usually a rabbit), and analyze the airway mucosa damage when the cuff pressure rises from 30 cmH 2 O to more than 40 cmH 2 O. The results are as Figure 10 shown in Figure 10 . It can be seen that a lubricating layer with a hydrogen-carrying complex provided by the embodiment of the present application can effectively improve the damage tolerance of the airway mucosa for the tracheal tube cuff with this lubricating layer.

[0162] In summary, the preparation method of a lubricating layer with a hydrogen-carrying complex provided by the embodiment of the present application is based on the adhesiveness and reducibility of polydopamine. Using polydopamine can bond palladium hydride nanoparticles to effectively reduce the damping property on the surface of palladium hydride particles and the ability of palladium hydride particles to bind hydrogen atoms, so as to improve the fluidity and hydrogen-carrying capacity of palladium hydride particles, thereby enabling precise control and continuous generation of active hydrogen between the cuff wall and the compressed mucosa to reduce mucosal damage caused by oxidative stress effects under compression ischemia.

[0163] In addition, a lubricating layer with a hydrogen-carrying complex provided by an embodiment of the present application. Both the polydopamine and palladium hydride particles in the lubricating layer have reducibility, that is, the lubricating layer has a strong ability to neutralize reactive oxygen species, and can remove the reactive oxygen species generated during the compression of the airway mucosa from the root cause of damage. In addition, both palladium hydride and polydopamine in the lubricating layer are mixed in a nanomaterial-based manner. Therefore, the functional molecules of the overall lubricating layer have low damping, that is, the functional molecules in the lubricating layer have good lubricity.

[0164] In addition, a lubricating layer with a hydrogen-carrying complex provided by an embodiment of the present application overcomes the controllability barrier of hydrogen supply in the biological field and overcomes the defects that pure hydrogen is difficult to control and extremely difficult to accurately act on the target position. Therefore, the lubricating layer realizes the controllable and triggered release of the action of hydrogen atoms.

[0165] The above are only the specific embodiments of the present application, enabling those skilled in the art to understand or implement the present application. Various modifications to these embodiments will be obvious to those skilled in the art. The general principles defined in the present application can be implemented in other embodiments without departing from the spirit or scope of the present application. Therefore, the present application will not be limited to these embodiments shown in the present application, but will conform to the widest scope consistent with the principles and novel features claimed in the present application.

Claims

1. A method for preparing a lubricating layer having a hydrogen-carrying complex, the method comprising: dispersing palladium nanoparticles in deionized water to obtain a palladium nanoparticle solution; Introducing hydrogen into the palladium nanoparticle solution in a bubbling manner to perform a hydrogenation reaction to obtain palladium hydride particles; dissolving polydopamine powder to obtain a polydopamine solution; Ultrasonic treatment is performed on the polydopamine solution and the palladium hydride particles to obtain a composite coating liquid; Spraying the composite coating liquid on the surface of the endotracheal tube cuff to obtain a composite coating; The composite coating is dried to obtain a lubricating layer having a hydrogen-carrying complex.

2. The preparation method according to claim 1, wherein the mass m1 of the polydopamine solute in the polydopamine solution and the mass m2 of the palladium hydride particles satisfy the relationship: m1:m2≥20:

1.

3. The preparation method according to claim 1, wherein the frequency of the ultrasonic treatment is 35kHz to 45kHz, and the time of the ultrasonic treatment is 30min to 60min.

4. The preparation method according to claim 1, wherein the spraying pressure is 0.2 MPa to 0.5 MPa, the spraying distance is 5 cm to 10 cm, and the number of spraying is 2 to 3 times.

5. The preparation method according to claim 1, wherein the diameter of the palladium nanoparticles is 5 nm to 10 nm; and / or The particle size of the polydopamine powder is 50nm to 200nm; and / or The mass concentration of the composite coating liquid is 0.5 mg / mL to 2 mg / mL.

6. The preparation method according to claim 1, wherein the preparation method of the polydopamine powder comprises: dissolving dopamine hydrochloride in tris(hydroxymethylaminomethane) hydrochloric acid buffer to obtain a dopamine hydrochloric acid solution; subjecting the dopamine hydrochloric acid solution to a self-oxidation reaction in an alkaline environment, so that the dopamine undergoes self-oxidation polymerization to obtain polydopamine nanoparticles; The polydopamine nanoparticles are freeze-dried to obtain polydopamine powder.

7. The preparation method according to claim 6, wherein the temperature of the self-oxidation reaction is 23°C to 27°C, the time of the self-oxidation reaction is 6h to 24h, and the pH of the self-oxidation reaction is 7 to 9.

8. The preparation method according to claim 6, wherein the self-oxidation reaction comprises carrying out the self-oxidation reaction under stirring, and the stirring speed is 200 rpm to 500 rpm; and / or The mass concentration of the dopamine hydrochloric acid solution is 0.5 mg / mL to 2 mg / mL.

9. A lubricating layer having a hydrogen-carrying complex, wherein the lubricating layer is prepared by the preparation method according to any one of claims 1 to 8. 10 . A cuff for an endotracheal tube, the surface of the cuff having the lubricating layer according to claim 9 .

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