Contact lens based on up-conversion luminescent nano material and preparation method thereof
By using uniaxial electrostatic spraying technology to form core-shell structured upconversion luminescent nanomaterials in contact lenses, the problem of low light transmittance caused by uneven nanoparticle dispersion has been solved, achieving high light transmittance and biocompatibility in contact lenses.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- GANSU KANGSHILI CONTACT LENS CO LTD
- Filing Date
- 2026-02-04
- Publication Date
- 2026-05-12
AI Technical Summary
The uneven dispersion of nanoparticles in the contact lens substrate leads to low light transmittance.
Rare-earth upconversion luminescent nanoparticles were encapsulated in a chitosan matrix using uniaxial electrostatic spraying technology to form a core-shell structured upconversion luminescent nanomaterial. This nanomaterial was then integrated into the contact lens substrate through a cross-linking reaction to form a natural refractive index gradient transition layer.
It significantly improves the light transmittance of contact lenses and enhances their affinity with corneal cells, avoiding direct contact between nanoparticles and corneal epithelial cells.
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Figure SMS_1
Abstract
Description
Technical Field
[0001] This invention relates to the field of contact lens technology, and in particular to a contact lens based on upconversion luminescent nanomaterials and its preparation method. Background Technology
[0002] Upconversion luminescent materials (such as rare-earth-doped nanoparticles), as nonlinear optical materials, can convert low-energy infrared photons into high-energy visible photons through nonlinear processes such as multiphoton absorption, which can then be captured by retinal cells, ultimately enabling the visualization of infrared light. Doping such upconversion nanoparticles into biocompatible polymers to prepare wearable devices (such as contact lenses) has enormous application potential, for example: assisting drivers in seeing in low-light conditions, improving nighttime reconnaissance capabilities, and enhancing the visual perception of patients with night blindness and cataracts in low-light environments. However, the direct dispersion of nanoparticles in contact lens substrates results in uneven dispersion, affecting the light transmittance of contact lenses. Therefore, researching a contact lens based on upconversion luminescent nanoparticles and its preparation method to improve the light transmittance of contact lenses is of great significance. Summary of the Invention
[0003] The purpose of this invention is to provide a contact lens based on upconversion luminescent nanomaterials and its preparation method, so as to solve the problems of uneven dispersion of nanoparticles and low light transmittance of contact lenses in the prior art.
[0004] To achieve the above-mentioned objectives, the present invention provides the following technical solution: This invention provides a contact lens based on upconversion luminescent nanomaterials, the contact lens comprising a contact lens substrate and a core-shell structured upconversion luminescent nanomaterial dispersed in the contact lens substrate; The core-shell structured upconversion luminescent nanomaterial is mainly composed of chitosan and rare earth upconversion luminescent nanoparticles.
[0005] Preferably, the rare-earth upconversion luminescent nanoparticles contain CaF2:Er 3+ Nanoparticles, NaYF4:Er,Ho nanoparticles, NaYF4:Er nanoparticles, or NaYF4:Er,Tm nanoparticles.
[0006] Preferably, the particle size of the rare earth on-conversion luminescent nanoparticles is 10~100nm.
[0007] This invention also provides a method for preparing contact lenses based on the above-described upconversion luminescent nanomaterials, comprising the following steps: (1) Rare earth upconversion luminescent nanoparticles were dispersed in a chitosan solution, and then subjected to uniaxial electrostatic spraying and freeze-drying to obtain core-shell structured upconversion luminescent nanomaterials; (2) Mix methacryloyloxypropyltris(trimethylsiloxane), N,N-dimethylacrylamide, N-vinylpyrrolidone, hydroxyethyl methacrylate, ethylene glycol dimethacrylate and an initiator to obtain a mixture; (3) Disperse the core-shell structured upconversion luminescent nanomaterial in water, and then mix the resulting dispersion with the above mixture to carry out a cross-linking reaction to obtain contact lenses.
[0008] Preferably, in step (1), the concentration of the chitosan solution is 10~20 mg / mL; and the content of the rare earth onconversion luminescent nanoparticles in the chitosan solution is 4~6 mg / mL.
[0009] Preferably, in step (1), the process parameters of the uniaxial electrostatic spray are: voltage of 5~15kV, injection flow rate of 0.1~1mm / min, and receiving distance of 5~10cm.
[0010] Preferably, the mass ratio of the methacryloyloxypropyltris(trimethylsiloxane)silane, N,N-dimethylacrylamide, N-vinylpyrrolidone, hydroxyethyl methacrylate, ethylene glycol dimethacrylate, and initiator is 30~40:20~40:10~15:8~15:0.3~0.8:0.1~0.6.
[0011] Preferably, the mass content of the core-shell structured upconversion luminescent nanomaterial in the mixture is 6-12%.
[0012] Preferably, the crosslinking reaction is carried out at a temperature of 80~120℃ for a time of 20~60min.
[0013] The beneficial effects of this invention are: (1) The present invention uses uniaxial electrostatic spraying technology to encapsulate rare earth upconversion luminescent nanoparticles in a chitosan matrix to form a core-shell structured upconversion luminescent nanomaterial. The chitosan shell forms a natural refractive index gradient transition layer between the luminescent nanoparticles and the contact lens substrate, which effectively reduces reflection loss and improves the emissivity of visible light generated by upconversion.
[0014] (2) The present invention significantly improves the light transmittance of contact lenses by adding upconversion luminescent nanomaterials with core-shell structure.
[0015] (3) Chitosan has excellent biocompatibility. Encapsulating rare earth upconversion luminescent nanoparticles in a chitosan matrix completely avoids direct contact between the luminescent nanoparticles and corneal epithelial cells, which is beneficial to enhancing the affinity with corneal cells. Detailed Implementation
[0016] This invention provides a contact lens based on upconversion luminescent nanomaterials, the contact lens comprising a contact lens substrate and a core-shell structured upconversion luminescent nanomaterial dispersed in the contact lens substrate; The core-shell structured upconversion luminescent nanomaterial is mainly composed of chitosan and rare earth upconversion luminescent nanoparticles.
[0017] In this invention, the rare-earth upconversion luminescent nanoparticles contain CaF2:Er 3+ Nanoparticles, NaYF4:Er,Ho nanoparticles, NaYF4:Er nanoparticles, or NaYF4:Er,Tm nanoparticles.
[0018] In this invention, the particle size of the rare earth on-conversion luminescent nanoparticles is 10~100nm, preferably 20~80nm, and more preferably 30~50nm.
[0019] This invention also provides a method for preparing contact lenses based on the above-described upconversion luminescent nanomaterials, comprising the following steps: (1) Rare earth upconversion luminescent nanoparticles were dispersed in a chitosan solution, and then subjected to uniaxial electrostatic spraying and freeze-drying to obtain core-shell structured upconversion luminescent nanomaterials; (2) Mix methacryloyloxypropyltris(trimethylsiloxane), N,N-dimethylacrylamide, N-vinylpyrrolidone, hydroxyethyl methacrylate, ethylene glycol dimethacrylate and an initiator to obtain a mixture; (3) Disperse the core-shell structured upconversion luminescent nanomaterial in water, and then mix the resulting dispersion with the above mixture to carry out a cross-linking reaction to obtain contact lenses.
[0020] In this invention, in step (1), the concentration of the chitosan solution is 10~20 mg / mL, specifically 10 mg / mL, 12 mg / mL, 15 mg / mL, 18 mg / mL, or 20 mg / mL; the content of the rare earth onconversion luminescent nanoparticles in the chitosan solution is 4~6 mg / mL, specifically 4 mg / mL, 5 mg / mL, or 6 mg / mL.
[0021] In this invention, the number-average molecular weight of the chitosan is 500,000 to 1,000,000.
[0022] In this invention, in step (1), the process parameters of the uniaxial electrostatic spray are as follows: voltage is 5~15kV, specifically 5kV, 6kV, 7kV, 8kV, 9kV, 10kV, 11kV, 12kV, 13kV, 14kV, 15kV; injection velocity is 0.1~1mm / min, specifically 0.2mm / min, 0.4mm / min, 0.5mm / min, 0.6mm / min, 0.8mm / min; receiving distance is 5~10cm, specifically 5cm, 6cm, 7cm, 8cm, 9cm, 10cm.
[0023] In this invention, the freeze-drying temperature is -40 to -20°C, specifically -40°C, -35°C, -30°C, -25°C, or -20°C; the freeze-drying time is 18 to 26 hours, specifically 20 hours, 22 hours, 24 hours, or 26 hours.
[0024] In this invention, the mass ratio of the methacryloyloxypropyltris(trimethylsiloxane)silane, N,N-dimethylacrylamide, N-vinylpyrrolidone, hydroxyethyl methacrylate, ethylene glycol dimethacrylate, and initiator is 30~40:20~40:10~15:8~15:0.3~0.8:0.1~0.6.
[0025] In this invention, the mass content of the core-shell structured upconversion luminescent nanomaterial in the mixed liquid is 6-12%, specifically 6%, 8%, 10%, or 12%.
[0026] In this invention, the temperature of the crosslinking reaction is 80~120℃, specifically 80℃, 90℃, 100℃, 110℃, or 120℃; the time is 20~60min, specifically 20min, 30min, 40min, 50min, or 60min.
[0027] The technical solutions provided by the present invention will be described in detail below with reference to the embodiments, but they should not be construed as limiting the scope of protection of the present invention.
[0028] Example 1
[0029] Chitosan (molecular weight 500,000-1,000,000) was dissolved in an aqueous acetic acid solution (1% concentration) and magnetically stirred overnight to obtain a chitosan solution with a concentration of 15 mg / mL. Then, NaYF4:Er,Ho nanoparticles (particle size 20-40 nm) were added to the chitosan solution, with a NaYF4:Er,Ho nanoparticle concentration of 5 mg / mL. The mixture was stirred at room temperature for 6 hours, followed by uniaxial electrostatic spraying with the following parameters: voltage 10 kV, injection flow rate 0.4 mm / min, receiving distance 8 cm, and aluminum foil as the receiving material. The collected material was freeze-dried at -30°C for 24 hours to obtain a core-shell structured upconversion luminescent nanomaterial. Methacryloxypropyltris(trimethylsiloxane)silane, N,N-dimethylacrylamide, N-vinylpyrrolidone, hydroxyethyl methacrylate, ethylene glycol dimethacrylate, and azobisisobutyronitrile were mixed evenly in a mass ratio of 35:30:12:10:0.7:0.5 to obtain a mixture. Upconversion luminescent nanomaterials with core-shell structure were dispersed in deionized water. The dispersion was then mixed with the above-mentioned mixture, wherein the mass content of the upconversion luminescent nanomaterials in the mixture was 10%. After magnetic stirring for 1 hour, the mixture was homogeneous. An appropriate amount of the homogeneous mixture was injected into a contact lens mold and placed at 80°C for crosslinking polymerization for 40 minutes. After the reaction was completed, the lens was taken out and soaked in 75% / 25%, 50% / 50%, and 25% / 75% ethanol / water mixtures for 4 hours each. Finally, it was soaked in pure water overnight to obtain a contact lens based on upconversion luminescent nanomaterials, which was designated as Sample-1.
[0030] Example 2
[0031] The difference from Example 1 is that the concentration of the chitosan solution was 20 mg / mL, while all other conditions were the same, resulting in contact lenses based on upconversion luminescent nanomaterials, denoted as Sample-2.
[0032] Example 3
[0033] The difference from Example 1 is that the concentration of the chitosan solution was 10 mg / mL, while all other conditions were the same, resulting in contact lenses based on upconversion luminescent nanomaterials, denoted as Sample-3.
[0034] Example 4
[0035] The difference from Example 1 is that the mass content of the core-shell structured upconversion luminescent nanomaterial in the mixture is 6%, while all other conditions are the same, resulting in contact lenses based on the upconversion luminescent nanomaterial, denoted as Sample-4.
[0036] Example 5
[0037] The difference from Example 1 is that the mass content of the core-shell structured upconversion luminescent nanomaterial in the mixture is 12%, while all other conditions are the same, resulting in contact lenses based on the upconversion luminescent nanomaterial, denoted as Sample-5.
[0038] Comparative Example 1
[0039] Methacryloxypropyltris(trimethylsiloxane)silane, N,N-dimethylacrylamide, N-vinylpyrrolidone, hydroxyethyl methacrylate, ethylene glycol dimethacrylate, and azobisisobutyronitrile were mixed evenly in a mass ratio of 35:30:12:10:0.7:0.5 to obtain a mixture. NaYF4:Er,Ho nanoparticles were dispersed in deionized water. The dispersion was then mixed with the above-mentioned mixture, wherein the mass content of NaYF4:Er,Ho nanoparticles in the mixture was 10%. After magnetic stirring for 1 hour, the mixture was homogeneous. An appropriate amount of the homogeneous mixture was injected into a contact lens mold and placed at 80°C for cross-linking polymerization for 40 minutes. After the reaction was completed, the lens was taken out and soaked in 75% / 25%, 50% / 50%, and 25% / 75% ethanol / water mixtures for 4 hours each. Finally, it was soaked in pure water overnight to obtain contact lenses based on upconversion luminescent nanoparticles, which was designated as control sample-1.
[0040] Comparative Example 2
[0041] The difference from Example 1 is that the concentration of the chitosan solution was 25 mg / mL, while all other conditions were the same, resulting in contact lenses based on upconversion luminescent nanomaterials, which were designated as Comparative Sample-2.
[0042] Comparative Example 3
[0043] The difference from Example 1 is that the concentration of the chitosan solution was 2 mg / mL, while all other conditions were the same, resulting in contact lenses based on upconversion luminescent nanomaterials, which were designated as control sample-3.
[0044] The samples from Examples 1-5 and Comparative Examples 1-3 were tested using the following methods: (1) Oxygen permeability: The oxygen permeability was determined by polarography according to ISO 9913-1 standard, and the unit is Dk / t. Dk is the oxygen permeability coefficient of the test sample, and t is the radial thickness or the average harmonic center thickness.
[0045] (2) Night vision effect: Using a fluorescence spectrophotometer, the excitation wavelength is 1.5um, and the emission of light at 550nm (visible light) is detected.
[0046] (3) Cytotoxicity: Tested according to ISO 10993-5-1999 standard.
[0047] (4) Visible light transmittance: The transmittance of the lens in the 400~700 nm wavelength range was measured using a UV-Vis spectrophotometer.
[0048] The test results are shown in Table 1: Table 1. Test results of Examples 1-5 and Comparative Examples 1-3
[0049] As shown in Table 1, the addition of core-shell upconversion luminescent nanomaterials significantly improved the light transmittance of contact lenses. The highest light transmittance, reaching 93.9%, was achieved when the mass content of the core-shell upconversion luminescent nanomaterials in the mixture was 10%. The light transmittance of the contact lenses decreased when the concentration of the chitosan solution was too low or too high.
[0050] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.
Claims
1. A contact lens based on upconversion luminescent nanomaterials, characterized in that, The contact lens includes a contact lens substrate and a core-shell structured upconversion luminescent nanomaterial dispersed in the contact lens substrate; The core-shell structured upconversion luminescent nanomaterial is mainly composed of chitosan and rare earth upconversion luminescent nanoparticles.
2. The contact lens based on upconversion luminescent nanomaterials according to claim 1, characterized in that, The rare-earth upconversion luminescent nanoparticles contain CaF2:Er 3+ Nanoparticles, NaYF4:Er,Ho nanoparticles, NaYF4:Er nanoparticles, or NaYF4:Er,Tm nanoparticles.
3. The contact lens based on upconversion luminescent nanomaterials according to claim 1 or 2, characterized in that, The rare earth on-conversion luminescent nanoparticles have a particle size of 10~100nm.
4. The method for preparing contact lenses based on upconversion luminescent nanomaterials according to any one of claims 1 to 3, characterized in that, Includes the following steps: (1) Rare earth upconversion luminescent nanoparticles were dispersed in a chitosan solution, and then subjected to uniaxial electrostatic spraying and freeze-drying to obtain core-shell structured upconversion luminescent nanomaterials; (2) Mix methacryloyloxypropyltris(trimethylsiloxane), N,N-dimethylacrylamide, N-vinylpyrrolidone, hydroxyethyl methacrylate, ethylene glycol dimethacrylate and an initiator to obtain a mixture; (3) Disperse the core-shell structured upconversion luminescent nanomaterial in water, and then mix the resulting dispersion with the above mixture to carry out a cross-linking reaction to obtain contact lenses.
5. The method for preparing contact lenses based on upconversion luminescent nanomaterials according to claim 4, characterized in that, In step (1), the concentration of the chitosan solution is 10~20 mg / mL; the content of the rare earth onconversion luminescent nanoparticles in the chitosan solution is 4~6 mg / mL.
6. The method for preparing contact lenses based on upconversion luminescent nanomaterials according to claim 4 or 5, characterized in that, In step (1), the process parameters of the uniaxial electrostatic spray are: voltage of 5~15kV, injection flow rate of 0.1~1mm / min, and receiving distance of 5~10cm.
7. The method for preparing contact lenses based on upconversion luminescent nanomaterials according to claim 6, characterized in that, The mass ratio of the methacryloyloxypropyltris(trimethylsiloxane)silane, N,N-dimethylacrylamide, N-vinylpyrrolidone, hydroxyethyl methacrylate, ethylene glycol dimethacrylate, and initiator is 30~40:20~40:10~15:8~15:0.3~0.8:0.1~0.
6.
8. The method for preparing contact lenses based on upconversion luminescent nanomaterials according to claim 5 or 7, characterized in that, The mass content of the core-shell structured upconversion luminescent nanomaterial in the mixture is 6-12%.
9. The method for preparing contact lenses based on upconversion luminescent nanomaterials according to claim 8, characterized in that, The cross-linking reaction is carried out at a temperature of 80~120℃ for a time of 20~60min.