Self-driven sensing contact lens with intraocular pressure monitoring function and preparation method thereof

Abstract

The invention relates to the technical field of contact lenses, in particular to a self-driven sensing contact lens with an intraocular pressure monitoring function and a preparation method of the self-driven sensing contact lens. Comprising a lens, a sensing assembly, an electrode structure and a monitoring characterization module, the sensing assembly comprises a silicon substrate and a nanowire array arranged on the upper surface of the silicon substrate, the nanowire array comprises a plurality of nanowires arranged at intervals, each nanowire is perpendicular to the upper surface of the silicon substrate, and the electrode structure is arranged on the upper surface of the silicon substrate. The sensing assembly is used for generating a water volt electric signal related to deformation when the silicon substrate is deformed; the electrode structure comprises a first electrode plate arranged between the sensing assembly and the inner side of the lens and a second electrode plate adhered to the side, away from the lens, of the sensing assembly. The self-driven sensing contact lens has high sensitivity and good biocompatibility, can comprehensively and continuously capture tiny shape changes of eyeballs in different states, and provides richer and more accurate data support for intraocular pressure monitoring.

Description

Technical Field

[0001] This invention relates to the field of contact lens technology, specifically to a self-driven sensing contact lens with intraocular pressure (IOP) monitoring function and its preparation method. Background Technology

[0002] Intraocular pressure (IOP), a crucial physiological parameter, plays an indispensable role in maintaining the normal shape of the eyeball, ensuring stable physiological functions, and preserving the optical properties of refractive media. It must remain stable within a specific physiological range; fluctuations outside this range can lead to eye diseases and threaten visual health. In the field of IOP monitoring, traditional methods typically require patients to undergo regular hospital checkups, which is inconvenient and cannot achieve real-time monitoring. While existing patents disclose the integration of micro-strain sensors into contact lenses to achieve continuous IOP monitoring, providing more data support for real-time, dynamic IOP monitoring and clinical diagnosis and treatment, these contact lens sensing systems suffer from several problems. For example, in terms of performance, existing micro-strain sensors have insufficient sensitivity, struggling to consistently and accurately output signals under static or quasi-static deformation, failing to provide long-term reliable IOP data, and thus failing to meet the clinical need for long-term continuous monitoring of slow physiological parameters, hindering disease diagnosis and treatment. Regarding power supply, most rely on external power sources, resulting in large system size, poor wearing comfort, insufficient circuit power, and frequent power supply or charging affecting monitoring continuity and accuracy, limiting clinical applications. Some self-powered sensors are prone to signal attenuation, decreased stability, or insufficient reliability in high-moisture human environments, limiting their application in physiological monitoring and hindering their widespread adoption. Therefore, developing a small, comfortable, highly sensitive intraocular pressure monitoring system that can provide long-term stable and continuous monitoring and performs reliably in high-moisture human environments is of great clinical significance and has broad application prospects. Summary of the Invention

[0003] The purpose of this invention is to provide a self-driven sensing contact lens with intraocular pressure monitoring function and its preparation method. By converting mechanical energy into electrical energy through the hydrovoltaic effect, continuous monitoring of intraocular pressure can be achieved without an external power source, thus solving the problem that existing contact lenses cannot stably and continuously monitor intraocular pressure for a long time.

[0004] To achieve the above objectives, the present invention provides the following technical solution: a self-driven sensing contact lens with intraocular pressure monitoring function, comprising: a lens, as the main structure, for fitting onto the surface of the eyeball; A sensing component includes a silicon substrate and a nanowire array disposed on the upper surface of the silicon substrate, the nanowire array comprising a plurality of spaced nanowires, each nanowire being perpendicular to the upper surface of the silicon substrate, the sensing component being used to generate a deformation-related hydrovoltaic signal when the silicon substrate undergoes deformation. The electrode structure includes a first electrode sheet and a second electrode sheet. The first electrode sheet is disposed between the inner side of the sensing component and the lens, and the second electrode sheet is attached to the surface of the sensing component away from the lens. The monitoring and characterization module, connected to the electrode structure, is used to characterize signals related to the hydroelectric signal.

[0005] Furthermore, the first electrode completely covers the lower surface of the silicon substrate; The second electrode sheet is attached to the central region of the upper surface of the nanowire array, and the area covered does not exceed 80% of the total area of ​​the upper surface of the nanowire array.

[0006] Furthermore, in the nanowire array, the diameter of the nanowire is set to any value between 10nm and 500nm, the spacing between two adjacent nanowires is any value between 10nm and 500nm, and the average height of the multiple nanowires is any value between 5μm and 30μm.

[0007] Furthermore, the ratio of the thickness of the silicon substrate to the average height of the plurality of nanowires is any value in the range of 10:(1-100).

[0008] Furthermore, the monitoring and characterization module includes a display module for displaying a light signal that is proportional to the hydroelectric signal.

[0009] Furthermore, the lens is made of a polymer, the thickness of the lens is limited to the range of 30μm-500μm, and the electrode structure is made of a composite of carbon nanotubes and the polymer.

[0010] This application also provides a method for preparing the above-mentioned self-driven sensing contact lens, comprising the following steps: S1. A lens is formed by casting the degassed mixed material, wherein the mixed material is a mixture of prepolymer and curing agent; S2. Mix carbon nanotubes, polymers and organic solvents evenly to form a mixture, and heat the mixture to obtain a composite. S3. Obtain a silicon substrate, perform chemical etching on the silicon substrate to form a nanowire array, and obtain a sensing component; S4. The composite obtained in step S2 is coated on the upper and lower surfaces of the sensing component to form a first electrode sheet and a second electrode sheet. S5. Bond the first electrode sheet to the lens; S6. Connect the first electrode plate and the second electrode plate to the monitoring and characterization module; S7. Perform thermosetting treatment at a temperature of 70℃-130℃ to fix the sensing component and the monitoring and characterization module to the lens to obtain a self-driven sensing contact lens.

[0011] Further, in step S1, the mass ratio of the prepolymer to the curing agent in the mixture is (7-12):1, and the curing temperature is any value between 70℃ and 130℃.

[0012] Further, in step S2, the concentration of carbon nanotubes in the mixture is 0.02-0.2 g / mL, and the heating treatment temperature is any value between 30℃ and 80℃.

[0013] Furthermore, in step S3, during the chemical etching process, metal nanoparticles are used as a catalyst and a mask to achieve selective etching.

[0014] The beneficial effects of this invention are as follows: The self-driven sensing contact lens with intraocular pressure monitoring function provided in this application, by combining the lens with a self-powered sensing component, can form a continuous and stable electrical output based on the structural characteristics of the nanowire array and the water-voltaic effect, and has high sensitivity. It can comprehensively and continuously capture the minute shape changes of the eyeball in different states, providing richer and more accurate data support for intraocular pressure monitoring.

[0015] The self-driven sensing contact lens provided in this application can work stably and reliably in a simulated body fluid environment, and has good biocompatibility. It will not irritate or cause adverse reactions to eye tissues, ensuring its safety for human use. In practical applications, it can accurately reflect the real situation of intraocular pressure, providing a new and feasible solution for intraocular pressure monitoring.

[0016] The self-driven sensing contact lens provided in this application can also be integrated with display modules such as LED devices. This not only demonstrates its great potential for seamless integration in functional systems, but also provides the possibility of achieving intuitive visual feedback, which can present the intraocular pressure monitoring results as intuitive visual signals, enabling users or medical personnel to quickly and conveniently obtain intraocular pressure information, greatly improving the efficiency and practicality of monitoring.

[0017] The above description is merely an overview of the technical solution of the present invention. In order to better understand the technical means of the present invention and to implement it in accordance with the contents of the specification, the preferred embodiments of the present invention are described in detail below with reference to the accompanying drawings. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the integrated structure of a self-driven sensing contact lens according to an embodiment of the present invention; Figure 2 This is a SEM image of the cross-section of the nanowire array shown in Embodiment 1 of the present invention; Figure 3 The output voltage curves of the self-driven sensing contact lens shown in Embodiment 1 of the present invention at different IOP levels are shown. Figure 4 The curve showing the relationship between the output voltage and IOP of the self-driven sensing contact lens as illustrated in Embodiment 1 of the present invention; Figure 5 This is a photograph of a self-driven sensing contact lens, as shown in Embodiment 1 of the present invention, worn on the eyeball of a live rabbit. Figure 6 The output voltage curve of the self-driven sensing contact lens worn on the rabbit's eyeball, as shown in Embodiment 1 of the present invention; Figure 7 Cell viability and proliferation status of the self-driven sensing contact lens shown in Embodiment 1 of the present invention, as detected by CCK-8 assay. Figure 8 The self-driven sensing contact lens shown in Embodiment 1 of the present invention distinguishes between live and non-living cells by live / dead fluorescence staining. Figure 9 This illustrates the electrical output when a self-driven sensing contact lens is integrated with an LED device, as shown in Embodiment 1 of the present invention. Figure label: 1. Lens; 2. Silicon substrate; 3. Nanowire array; 5. First electrode sheet; 4. Second electrode sheet; 6. Mold. Detailed Implementation

[0019] The technical solution of the present invention will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0020] In the description of this invention, it should be noted that the terms "center," "upper," "lower," "vertical," "horizontal," and "inner," etc., indicating orientation or positional relationships, are based on the orientation or positional relationships shown in the accompanying drawings and are only for the convenience of describing the invention and simplifying the description, not to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the invention. Furthermore, the terms "first," "second," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance. In the description of this invention, it should be noted that unless otherwise explicitly specified and limited, the terms "connected" and "linked" should be interpreted broadly. For example, it can refer to a fixed connection, a detachable connection, or an integral connection; it can refer to a mechanical connection or an electrical connection; it can refer to a direct connection or an indirect connection through an intermediate medium; it can refer to the internal connection of two elements. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances. Furthermore, the technical features involved in the different embodiments of the invention described below can be combined with each other as long as they do not conflict with each other.

[0021] Please see Figure 1A preferred embodiment of this application discloses a self-driven sensing contact lens with intraocular pressure monitoring function, comprising a lens 1, a sensing component, an electrode structure, and a monitoring and characterization module. This self-driven sensing contact lens utilizes the structural features of the sensing component to generate a deformation-induced voltaic effect, thereby forming a continuous and stable electrical output to monitor changes in intraocular pressure. The sensing component includes a silicon substrate 2 and a nanowire array 3. The nanowire array 3 includes multiple nanowires spaced apart on the silicon substrate 2, and each nanowire is perpendicular to the upper surface of the silicon substrate 2. The sensing component generates a deformation-related voltaic signal when the silicon substrate 2 deforms; that is, when the silicon substrate 2 deforms, it causes a change in the shape of the nanowire array 3, resulting in a change in the spacing between the tips of the multiple nanowires, thereby causing a change in the voltaic output of the nanowire array 3, realizing the intraocular pressure sensing function. The electrode structure includes a first electrode sheet 5 and a second electrode sheet 4. The first electrode sheet 5 is disposed between the sensing component and the inner side of the lens 1. The second electrode sheet 4 is attached to the surface of the sensing component away from the lens 1. A conductive path is formed between the second electrode 4 and the first electrode 5 to convert changes in intraocular pressure into a transmittable electrical signal. The monitoring and characterization module is connected to the electrode structure to characterize signals related to the water voltage signal. Based on the structural features of the nanowire array 3, the sensing component in this self-driven sensing contact lens possesses intraocular pressure sensing capabilities under water-containing conditions. It maintains stable and continuous electrical output performance on the surface of the eye with high water content, exhibiting excellent anti-interference capabilities and environmental adaptability. It does not suffer from signal attenuation, decreased stability, or insufficient reliability due to high water content, thus making this self-driven sensing contact lens a promising candidate for applications in physiological monitoring.

[0022] In one embodiment, the monitoring and characterization module includes a display module for displaying a light signal proportional to the water voltage signal. Under normal operating conditions, the sensing component continuously monitors changes in intraocular pressure while providing power to the display module. Based on the power provided by the sensing component, the display module can characterize the monitoring data collected by the sensing component and directly present the monitoring results, enabling the monitoring results to be conveyed to the user intuitively and accurately. In this embodiment and other embodiments, it is preferable that the first electrode 5 completely covers the lower surface of the silicon substrate 2; the second electrode 4 is attached to the central region of the upper surface of the nanowire array 3, and the area of ​​its coverage does not exceed 80% of the total area of ​​the upper surface of the nanowire array 3. Since the generation and transmission path of the electrical signal during the deformation of the nanowire array 3 depends on the layout of the electrode 4, attaching the second electrode 4 to the central region ensures that its effective contact area with the nanowire array 3 is in a position where the deformation is relatively uniform and significant. This ensures that the electrical signal generated by the deformation of the nanowire array 3 can be accurately and efficiently captured and smoothly transmitted to subsequent circuits for further processing and analysis. Meanwhile, by limiting the coverage area of ​​the second electrode 4, sufficient contact space can be reserved between the nanowires and the liquid, ensuring that the liquid can flow freely in the nanowire array 3, thereby generating a stable and sufficiently strong water voltaic signal; it also helps to ensure that a stable and reliable electrical connection is formed between the second electrode 4 and the nanowire array 3, so that the electrical signal can be transmitted smoothly, providing accurate data support for subsequent intraocular pressure monitoring.

[0023] In one embodiment, the parameters of the nanowire array 3 were precisely set. Specifically, the diameter of the nanowires was set to any value within the range of 10 nm to 500 nm, the spacing between two adjacent nanowires was set to any value within the range of 10 nm to 500 nm, and the average height of the multiple nanowires was set to any value within the range of 5 μm to 30 μm. By adjusting the diameter of the nanowires and the spacing between adjacent nanowires, the density of nanowires on the silicon substrate 2 can be effectively controlled, thereby adjusting and optimizing the interaction between the nanowire array 3 and the liquid. Reasonably defined nanowire diameters and spacing between adjacent nanowires ensure sufficient liquid flow within the nanowire array 3, thereby improving the stability and intensity of the water-voltaic output. Simultaneously, this also helps improve the signal output stability of the sensor under static or quasi-static deformation conditions, meeting the requirements for long-term monitoring of intraocular pressure parameters. In this embodiment and other embodiments, the ratio of the thickness of the silicon substrate 2 to the average height of the multiple nanowires is set to 10:(1-100). By limiting the ratio between the height of the nanowires and the thickness of the silicon substrate 2, the spacing between the tips of adjacent nanowires can be effectively altered during deformation, thereby stably inducing changes in the hydrovoltaic output and significantly improving the accuracy and reliability of the sensing. Simultaneously, through comprehensive optimization and limitation of the average height of the nanowires and the thickness of the silicon substrate 2, the overall thickness of the sensing component can be rationally designed, ensuring both good flexibility and sufficient mechanical strength. This allows the sensing component 2 to flexibly adapt to deformations of varying degrees of bending, ensuring a linear response between nanowire deformation and intraocular pressure changes, thus improving monitoring accuracy; and it can also withstand external pressure to a certain extent, ensuring stable operation in complex working environments.

[0024] In one embodiment, the material of lens 1 is preferably a polymer material, such as polydimethylsiloxane (PDMS). The thickness of lens 1 is limited to the range of 30μm-500μm. Simultaneously, to ensure the structural rationality and performance stability of the entire self-driven sensing contact lens, the thickness of the sensing component is limited to not exceeding the thickness of lens 1. Limiting the thickness of lens 1 within this range not only provides sufficient and appropriate oxygen supply to the eyeball, meeting the oxygen requirements for normal physiological activities and effectively avoiding eye discomfort or diseases caused by insufficient oxygen permeability, but also helps ensure that lens 1 has sufficient strength and toughness. It will not easily deform during daily wear or operation due to excessive thinness, affecting its normal function and wearing comfort, nor will it cause difficulties in the demolding process during manufacturing due to excessive thickness, reducing the defect rate in the production process and improving production efficiency and product quality. Limiting the thickness of the sensing component to no more than the thickness of lens 1 helps achieve good physical compatibility and adaptation between the sensing component and lens 1. This ensures their spatial structural coordination, allowing for a tight fit and seamless integration. It also ensures mutual matching in terms of physical properties such as stress and deformation, guaranteeing that the sensing component and lens 1 can work together to perform intraocular pressure monitoring in various usage scenarios without interference or damage due to physical mismatch. In this embodiment and other embodiments, the electrode structure is made of a composite of carbon nanotubes (CNTs) and polymer materials. The high conductivity of carbon nanotubes improves signal conversion efficiency, while the polymer enhances the adhesion between the electrode structure and the sensing component. Furthermore, it is preferable that the polymer material used in the electrode structure is consistent with the material of lens 1 to improve compatibility between the electrode structure and lens 1. This allows for more coordinated deformation of lens 1 and electrode structure under temperature changes or external forces, reducing stress concentration caused by material differences and lowering the risk of structural damage.

[0025] This application also provides a method for preparing the above-mentioned self-driven sensing contact lens, comprising the following steps: S1. Lens 1 is formed by casting the degassed mixture, and the result is as follows: Figure 1 As shown in (b), the mixed material is a mixture of prepolymer and curing agent; S2. Mix carbon nanotubes, polymers and organic solvents evenly to form a mixture, and heat the mixture to obtain a composite. S3. Obtain silicon substrate 2, and perform chemical etching on silicon substrate 2 to form nanowire array 3, as shown in the figure. Figure 1 As shown in (c), the sensing component is obtained; S4. The composite material obtained in step S2 is coated on the upper and lower surfaces of the sensing component, and the result is as follows. Figure 1As shown in (d), a first electrode plate 5 and a second electrode plate 4 are formed; S5. Bond the first electrode sheet 5 to the lens 1; S6. Connect the first electrode plate 5 and the second electrode plate 4 to the monitoring and characterization module; S7. A thermosetting process was performed at a temperature of 70℃-130℃ to fix the sensing components and monitoring / characterization module to lens 1. The results are as follows: Figure 1 As shown in (e), a self-driven sensing contact lens is obtained.

[0026] In step S1, degassing effectively removes air bubbles from the mixture of prepolymer and curing agent, preventing them from negatively impacting the quality of lens 1. The degassing process typically involves using a vacuum degassing device to continuously evacuate the mixture under a set vacuum level, effectively removing air bubbles. The size and shape of mold 6 must be precisely designed and manufactured according to the final specifications of lens 1. During curing, the curing temperature and time can be controlled to ensure complete curing of the mixture, thus forming a prototype lens 1 with good physical and chemical properties. After curing, mold 6 must be allowed to cool naturally to a suitable temperature before demolding to avoid damaging lens 1.

[0027] In step S2, an ultrasonic dispersion device can be used to ultrasonically treat the mixture under certain ultrasonic power and time conditions, so that the carbon nanotubes and polymers are fully dispersed in the organic solvent to form a uniform and stable mixture. During the heating process, it is necessary to observe the state changes of the mixture to ensure that the polymer can fully interact with the carbon nanotubes to form a composite with good properties.

[0028] In step S3, before chemical etching of the silicon substrate 2, the substrate can be cleaned to remove surface impurities and contaminants to ensure the smooth progress of subsequent chemical etching. During the etching process, parameters such as etching time, temperature, and etching solution concentration can be controlled to form multiple neatly arranged and uniformly sized nanowires on the silicon substrate 2 according to design requirements. These nanowires together form a nanowire array 3, thereby obtaining a sensing component with intraocular pressure sensing function.

[0029] In step S7, the composite material is fully cured through the thermal curing process, which firmly bonds the sensing component to the lens 1 and ensures a stable connection between the monitoring and characterization module and the sensing component, ultimately resulting in a high-performance self-driven sensing contact lens.

[0030] In one embodiment, in step S1, the mass ratio of the prepolymer to the curing agent in the mixture is limited to (7-12):1, allowing the prepolymer and curing agent to react fully and form a polymer network structure with good physical and chemical properties. This ensures that the final lens 1 possesses suitable hardness, elasticity, and optical properties. The curing temperature is set to any value between 70℃ and 130℃ to ensure that the curing reaction proceeds at a suitable rate. This prevents incomplete reaction due to excessively low temperatures, which could affect the quality of lens 1, and also prevents side reactions due to excessively high temperatures, which could damage the structure and performance of lens 1. In this embodiment and other embodiments, in step S2, the concentration of carbon nanotubes in the mixture is limited to the range of 0.02 g / mL to 0.2 g / mL, allowing the carbon nanotubes to be uniformly dispersed in the organic solvent and fully mixed and interact with the polymer to form a high-performance composite. The polymer is a substance formed by polymerizing the prepolymer. The heat treatment temperature is any value between 30℃ and 80℃. This temperature range can provide a suitable environment for the fusion of polymer and carbon nanotubes, promote the formation of stable chemical bonds and physical structures between them, and thus improve the overall performance of the composite.

[0031] In one embodiment, in step S3, during the chemical etching process, metal nanoparticles are used as a catalyst and mask to achieve selective etching. During chemical etching, the metal nanoparticles act as a mask to protect the covered area from etching while simultaneously catalyzing the etching reaction in the uncovered areas, thereby forming nanowires with precisely controlled diameter and uniformity, further enhancing the intraocular pressure monitoring performance of the self-driven sensor contact lens. The metal nanoparticles are preferably gold, silver, or platinum, with a particle size limited to the range of 10 nm to 100 nm. By precisely controlling the metal particle size, the distribution of catalytic active sites during the chemical etching process can be optimized, improving catalytic efficiency and enhancing etching selectivity, allowing for precise control of the nanowire morphology (such as diameter and uniformity).

[0032] Example 1 S1. Weigh 10g of dimethylsiloxane monomer as the prepolymer, and weigh 1g of curing agent (Sylgard184). Mix the weighed prepolymer and curing agent evenly, and place them in a vacuum degassing device for 30 minutes to degas and form a mixture. Then, pour 0.5mL of the mixture into the contact lens mold and cure it at 110℃ for 1 hour. After curing, remove the mold from the constant temperature curing chamber and allow it to cool to a suitable temperature before demolding.

[0033] S2. Weigh 5 mL of polydimethylsiloxane, 10 mL of dichloromethane, and 0.3 g of carbon nanotubes. Mix the weighed carbon nanotubes, polydimethylsiloxane, and organic solvent evenly to form a mixture. Heat the mixture at 40°C to obtain the composite. Polydimethylsiloxane is a polymer obtained by polymerization of dimethylsiloxane monomer as a prepolymer.

[0034] S3. Obtain an n-type silicon substrate with a thickness of 60 μm. First, immerse the silicon substrate in a seed solution containing 0.05 M AgNO3 and 4.5 M HF for 15 seconds, then remove it to allow Ag nanoparticles to deposit on the silicon substrate surface. Subsequently, transfer the silicon substrate to a mixture of 0.4 M H2O2 and 4.8 M HF for etching for 15 minutes. Then, immerse the silicon substrate in a 5.4 M HNO3 solution to dissolve the remaining Ag nanoparticles on the silicon substrate. After the Ag nanoparticles are dissolved, remove the silicon substrate, rinse it with deionized water, and dry it under a nitrogen flow. Finally, as shown... Figure 2 As shown, the silicon substrate is thinned to 6 μm and a nanowire array is formed on the silicon substrate with an average height of 15 μm to obtain a sensing component.

[0035] S4. The composite obtained in step S2 is coated on the upper and lower surfaces of the sensing component to form the first electrode sheet and the second electrode sheet.

[0036] S5. Adhere the first electrode sheet to the inside of the lens.

[0037] S6. Connect the first electrode plate and the second electrode plate to the monitoring and characterization module.

[0038] S7. Perform heat curing treatment at a temperature of 110℃ to fix the sensing components and monitoring characterization module to the lens. After curing for 1 hour, a self-driven sensing contact lens is obtained.

[0039] To comprehensively evaluate the practical application performance of the self-driven sensing contact lens prepared in Example 1 in the field of intraocular pressure (IOP) monitoring, its performance was tested. Considering the close anatomical size of pig eyes compared to human eyes, and their similarities in physiological structure and function, surgical pig eyes were selected to construct the IOP monitoring model. This aimed to simulate the real environment of the human eye as closely as possible, ensuring the reliability and generalizability of the test results. Furthermore, a PVC (polyvinyl chloride) pipeline was used to tightly connect the digital pressure gauge, the pig eye, and the syringe pump, constructing a testing system capable of real-time display and calibration of intraocular pressure. During the test, the self-driven sensing contact lens was attached to the surface of the pig eye, ensuring a tight fit between the lens and the cornea to avoid gaps or air bubbles that could affect signal acquisition and transmission. Subsequently, the pig eye with the self-driven sensing contact lens attached was completely immersed in water with a composition and osmotic pressure similar to human tears, simulating the physiological aquatic environment of the eye and making the test conditions closer to actual human conditions. Physiological saline was injected or drawn using the syringe pump to adjust changes in intraocular pressure. During the adjustment process, closely observe the changes in the reading of the digital pressure gauge to ensure that the intraocular pressure changes according to the preset gradient, and at the same time record the electrical signal output of the self-driven sensor contact lens corresponding to each pressure point.

[0040] It should be noted that the average Young's modulus of porcine corneas is higher than that of human corneas. Young's modulus is a physical quantity that describes the stress-strain relationship of a material within its elastic deformation range. A higher Young's modulus means that under the same intraocular pressure change, the deformation of the porcine cornea is relatively smaller. This places higher demands on the detection sensitivity of the self-driven sensing contact lens. If this self-driven sensing contact lens can accurately detect the minute deformations of the porcine cornea under these conditions and convert them into measurable electrical signals, then it fully demonstrates its strong application potential and reliability in monitoring intraocular pressure in the human eye.

[0041] During the test, the initial intraocular pressure was precisely set to 7.5 mmHg. Figure 1 As shown in (e), to maintain the shape of the eyeball. Since the intraocular pressure (IOP) of a healthy human eye is typically between 10 mmHg and 21 mmHg, while glaucoma patients may experience higher or lower pressures, to comprehensively evaluate the performance of this self-driven sensing contact lens under different intraocular pressure conditions, especially simulating extreme intraocular pressure situations that may occur in glaucoma patients, a step-by-step increase in IOP was used during the test, gradually increasing the IOP from an initial 7.5 mmHg to 30 mmHg, while simultaneously monitoring and recording changes in the output voltage of the sensing component. The results show that the output voltage exhibits a regular change corresponding to changes in IOP. Specifically, as shown... Figure 3As shown, the output voltage of the sensing component gradually decreases as intraocular pressure continues to rise. This is because when intraocular pressure increases, the surface of the eyeball undergoes a certain degree of deformation. This deformation is transmitted to the sensing component attached to the surface of the eyeball, causing the sensing component to bend, and the degree of bending continuously increases. This mechanical deformation of the sensing component changes its internal charge distribution and conductivity, thereby causing a corresponding change in the output voltage.

[0042] To quantify the sensitivity of this self-driven sensing contact lens to changes in intraocular pressure (IOP), a performance metric called pressure responsiveness (PR) was introduced and defined. PR directly reflects the response characteristics of the sensing component's output signal to changes in intraocular pressure, and its value can be calculated using the following equation: , Where ΔIOP represents the change in intraocular pressure, measured in millimeters of mercury (mmHg); ΔV represents the change in the output voltage of the sensing component, measured in millivolts (mV). Calculations show that, as... Figure 4 As shown, the pressure response of this sensing component reaches -4.4 mV / mmHg. The negative sign indicates that the output voltage is inversely related to changes in intraocular pressure, meaning that the output voltage decreases when intraocular pressure increases. This high pressure response value fully demonstrates the excellent sensitivity of this self-driven sensing contact lens, enabling it to generate significant and measurable changes in electrical signals even with subtle changes in intraocular pressure.

[0043] Furthermore, analysis of the relationship between output voltage and intraocular pressure reveals a good linear response between the output voltage and IOP. The correlation coefficient R was calculated using a linear fitting method. 2 The correlation coefficient is 0.99, which is extremely close to the ideal value of 1. This correlation coefficient indicates a close and stable linear relationship between the output voltage and intraocular pressure, thereby ensuring the reliability of the self-driven sensing contact lens in terms of signal discrimination ability and pressure response correlation, and providing accurate and reliable data support for intraocular pressure monitoring.

[0044] Minimum detection resolution (Res) is also an important indicator for evaluating sensor performance, reflecting the smallest change in intraocular pressure that the sensor can detect. The minimum detection resolution (Res) of this self-driven sensing contact lens can be calculated using the following equation: Where σ is the standard deviation of the output voltage, used to measure the dispersion of the output voltage signal; GF is the strain sensitivity coefficient of the sensing component, and its calculation formula is: Where ΔV / V0 represents the relative change in the output voltage of the sensing component, and ε is the applied strain. By accurately measuring the standard deviation of the output voltage and combining it with the calculated pressure responsiveness value, the detection resolution of this self-powered sensing contact lens is calculated to be 0.74 mmHg. This detection resolution significantly exceeds the 1-2 mmHg resolution requirement of the widely used clinical gold standard—the Goldmann applanation tonometer. This result demonstrates that this self-powered sensing contact lens possesses highly sensitive detection capabilities, enabling precise and timely tracking of minute dynamic changes in physiological intraocular pressure. Whether in routine monitoring of physiological intraocular pressure fluctuations or in the early diagnosis and treatment of eye diseases, this self-powered sensing contact lens can provide a self-powered, continuous, and stable static intraocular pressure output signal within the physiological pressure range, providing strong technical support for eye health monitoring and disease management.

[0045] To comprehensively evaluate the self-powered performance of this self-powered sensing contact lens in a biological aquatic environment, a series of experimental tests were designed and conducted. During the testing phase, such as... Figure 5 As shown, a rabbit eye was selected as the experimental subject, and the self-driven sensing contact lens was securely attached to its surface. To ensure accurate data acquisition, copper wires were used to electrically connect the sensing component of the self-driven sensing contact lens to an electrochemical workstation (model CHI630E), and the output voltage signal was recorded in real time and accurately using a data acquisition system. Throughout the testing process, experimental conditions were strictly controlled to ensure the rabbit eye was in a stable physiological state, thus eliminating interference from external factors on the test results.

[0046] Test results are as follows Figure 6 As shown, under tear hydration, this self-powered sensing contact lens can continuously generate a stable and consistent voltage signal. This phenomenon fully demonstrates that the self-powered sensing contact lens possesses reliable self-powering capability and long-term continuous stable operation characteristics in a biological aquatic environment. This also indicates that in practical eye monitoring applications, this self-powered sensing contact lens can operate independently and stably in complex ocular physiological environments without external power supply support, providing energy security for subsequent applications such as intraocular pressure monitoring.

[0047] Biocompatibility is a key indicator for evaluating the safe application of medical devices in humans. To comprehensively evaluate the biocompatibility of this self-powered sensing contact lens, two experimental methods were used: CCK-8 cell viability assay and live / dead fluorescence staining. The test results are as follows: Figure 7 , Figure 8 As shown.

[0048] In the CCK-8 cell viability assay, the self-powered sensing contact lens was co-cultured with mouse embryonic fibroblasts (MEF) for 1-3 days. Throughout the culture process, the standard operating procedures for cell culture were strictly followed to ensure a suitable and stable growth environment for the cells. Figure 7 As shown in the results, after 1-3 days of co-culture, the cell viability exceeded 90%, and there was no significant difference in cell viability compared to the control group that did not come into contact with the contact lens. This result indicates that the self-driven sensing contact lens does not significantly inhibit or toxicize the normal growth and metabolism of cells during direct contact, demonstrating good cell compatibility.

[0049] The biocompatibility of this contact lens was further verified from the perspective of cell morphology and survival status through live / dead fluorescence staining experiments. Figure 8 As shown, the cells co-cultured with the self-driven sensing contact lens maintained their morphology well, with clear cell structures and no obvious abnormal morphological changes such as cell shrinkage or rupture. Simultaneously, no obvious cell death or apoptosis signals were detected; most cells exhibited green fluorescence (representing live cells), and virtually no cells exhibited red fluorescence (representing dead cells). This further demonstrates that the sensor material used in this self-driven sensing contact lens possesses excellent cell compatibility, maintaining the normal physiological state of cells during long-term contact, thus providing a reliable safety guarantee for its application in biological tissues such as the human eye.

[0050] To verify the significant potential of this sensing component in wearable devices, a self-powered sensing contact lens was integrated with a commercial LED device. Specifically, microelectronic interconnect technology was used to electrically connect the sensing component within the self-powered contact lens to the LED device. Subsequently, the performance of the integrated contact lens was tested in environments without biological fluids such as tears and in tear-water environments. The results are as follows: Figure 9 As shown.

[0051] like Figure 9 As shown in (a), under dry conditions, in an environment devoid of biological fluids such as tears, the self-powered sensing contact lens failed to illuminate the LED device. This phenomenon indicates that in the absence of the crucial conditions provided by a biological aquatic environment, the sensing component cannot generate sufficient electrical energy to drive the LED device. However, in a tear-rich environment, such as… Figure 9As shown in (b) and (c), the sensing component in this self-powered sensing contact lens generates electrical energy capable of driving the connected LED device through the water voltaic effect in the aquatic environment. This water voltaic effect is an energy conversion mechanism based on the interaction between a nanowire array and water, generating sufficient electrical energy to drive the connected LED device, causing it to emit noticeable and stable brightness. This visual effect also demonstrates the energy generation capability of the sensing component in a biological aquatic environment. Therefore, the self-powered sensing contact lens provided in this application has a dual-functional sensing component. Specifically, the sensing component possesses high-sensitivity sensing capabilities, capable of detecting minute deformations of the eyeball and converting them into electrical signals, providing a reliable technical means for monitoring physiological parameters such as intraocular pressure; simultaneously, in the presence of physiological environments such as tears, the sensing component can generate sufficient electrical energy through the water voltaic effect, thus serving as a potential internal energy source to provide power to other integrated modules. Therefore, based on this sensing component, a highly integrated contact lens or other wearable device can be designed to monitor intraocular pressure changes in real time. This provides crucial data support for the early diagnosis and prevention of eye diseases. Simultaneously, it utilizes its own generated power to drive display modules such as LED devices, presenting the monitoring results to users or medical personnel in an intuitive visual signal format, such as using changes in LED brightness or flashing frequency to represent intraocular pressure levels. This eliminates the need for an external power source or a signal transmission module to transmit detection results to an external display device, significantly improving the portability and practicality of the highly integrated contact lens or other wearable device.

[0052] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0053] The embodiments described above are merely illustrative of several implementations of the present invention, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the invention patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these all fall within the protection scope of the present invention. Therefore, the protection scope of this invention patent should be determined by the appended claims.

Claims

1. A self-driven sensor contact lens having an intraocular pressure monitoring function, characterized by, include: Lenses, as the main structure, are used to adhere to the surface of the eyeball; A sensing component includes a silicon substrate and a nanowire array disposed on the upper surface of the silicon substrate, the nanowire array comprising a plurality of spaced nanowires, each nanowire being perpendicular to the upper surface of the silicon substrate, the sensing component being used to generate a deformation-related hydrovoltaic signal when the silicon substrate undergoes deformation. The electrode structure includes a first electrode sheet and a second electrode sheet. The first electrode sheet is disposed between the inner side of the sensing component and the lens, and the second electrode sheet is attached to the surface of the sensing component away from the lens. A monitoring and characterization module, connected to the electrode structure, is used to characterize signals related to the hydroelectric signal.

2. The self-powered, sensory contact lens of claim 1, wherein, The first electrode completely covers the lower surface of the silicon substrate; The second electrode sheet is attached to the central region of the upper surface of the nanowire array, and the area covered does not exceed 80% of the total area of ​​the upper surface of the nanowire array.

3. The self-powered, sensory contact lens of claim 1, wherein, In the nanowire array, the diameter of the nanowire is set to any value between 10nm and 500nm, the spacing between two adjacent nanowires is any value between 10nm and 500nm, and the average height of the multiple nanowires is any value between 5μm and 30μm.

4. The self-powered, sensory contact lens of claim 3, wherein, The ratio of the thickness of the silicon substrate to the average height of the plurality of nanowires is any value in the range of 10:(1-100).

5. The self-actuated sensory contact lens of any one of claims 1-4, wherein, The monitoring and characterization module includes a display module for displaying a light signal that is proportional to the hydroelectric signal.

6. The self-powered sensory contact lens of any one of claim 5, wherein, The lens is made of polymer, and the thickness of the lens is limited to the range of 30μm-500μm. The electrode structure is made of a composite of carbon nanotubes and the polymer.

7. The method of claim 1-6, wherein the self- powered sensor contact lens is prepared by, Includes the following steps: S1. A lens is formed by casting the degassed mixed material, wherein the mixed material is a mixture of prepolymer and curing agent; S2. Mix carbon nanotubes, polymers and organic solvents evenly to form a mixture, and heat the mixture to obtain a composite. S3. Obtain a silicon substrate, perform chemical etching on the silicon substrate to form a nanowire array, and obtain a sensing component; S4. The composite obtained in step S2 is coated on the upper and lower surfaces of the sensing component to form a first electrode sheet and a second electrode sheet. S5. Bond the first electrode sheet to the lens; S6. Connect the first electrode plate and the second electrode plate to the monitoring and characterization module; S7. Perform thermosetting treatment at a temperature of 70℃-130℃ to fix the sensing component and the monitoring and characterization module to the lens to obtain a self-driven sensing contact lens.

8. The production method according to claim 1, wherein In step S1, the mass ratio of the prepolymer to the curing agent in the mixture is (7-12):1, and the curing temperature is any value between 70℃ and 130℃.

9. The production method according to claim 2, wherein In step S2, the concentration of carbon nanotubes in the mixture is 0.02-0.2 g / mL, and the heating treatment temperature is any value between 30℃ and 80℃.

10. The production method according to claim 1, wherein In step S3, during the chemical etching process, metal nanoparticles are used as catalysts and masks to achieve selective etching.

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