Polymer capsule based on photoelectric responsiveness and preparation method thereof

Abstract

The invention relates to a photoelectric responsive polymer capsule and a preparation method thereof. The capsule comprises a photoelectric responsive polymer shell and a drug core. The photoelectric responsive polymer shell has sensitivity to light, and can generate reversible structural changes, including contraction, expansion or formation and closing of holes, under an illumination condition. The drug core is located in the photoelectric responsive polymer shell and interacts with the shell, and controllable release of the drug is achieved. The photoelectric responsive polymer capsule disclosed by the invention can realize high controllability of drug release under an illumination condition, and has the advantages of accuracy, reversibility and adjustability. The preparation method is simple and effective, and is suitable for sustained release requirements of various drugs.

Description

Technical Field

[0001] This invention relates to the field of drug sustained release, and more specifically, to a photoelectro-responsive polymer capsule and its preparation method. Background Technology

[0002] Controlled drug delivery systems can precisely release packaged drug molecules at the lesion site in time and space under specific stimulus conditions, offering numerous advantages such as high drug utilization and low toxicity, providing new insights for the precision treatment of various major diseases, such as cancer. Therefore, the design and development of stimulus-triggered controlled drug delivery systems is receiving widespread attention from researchers. The materials constituting controlled drug delivery systems are called "smart materials," which can respond to stimuli from the organism's internal environment (pH, redox, enzymes, etc.) or external environment (temperature, electricity / magnetism, ultrasound, and light, etc.). Before and after the response, the material undergoes changes in composition or conformation, disrupting the original equilibrium of the delivery system and thus releasing the drug. Light is a clean, non-invasive, and effective stimulus source. The use of light of specific wavelengths for the precise treatment of tumors mainly includes photodynamic therapy, photothermal therapy, photoacoustic imaging, and light-controlled drug delivery systems. Among these treatment systems, light-controlled drug delivery systems achieve high-concentration light-controlled release of drugs at the lesion site by adjusting the wavelength and intensity of light, as well as the illumination time and space, thereby reducing the toxicity of drugs to normal sites. Therefore, light-controlled drug delivery systems have great application value and broad development prospects in the biomedical field.

[0003] Traditional drug delivery systems are often limited by external factors such as temperature and pH, making their control challenging. Among numerous controlled-release drug delivery systems, photocontrolled drug delivery systems, which utilize specific light illumination to control drug release, have shown broad application potential and attracted widespread attention from researchers. Photoresponsive polymers possess high light sensitivity and can undergo reversible structural changes under light conditions; therefore, they can be applied to drug delivery systems to achieve highly precise control over drug release. Summary of the Invention

[0004] The purpose of this invention is to address the shortcomings of existing technologies by providing a photosensitive polymer capsule for drug sustained release and its preparation method. The photosensitive polymer shell is sensitive to light and undergoes reversible structural changes under light irradiation, including contraction, expansion, or the formation and closure of pores. The drug core is located within the photosensitive polymer shell and interacts with it, achieving controlled drug release. Special processes during capsule preparation ensure the capsule's stability and controllability, making it suitable for a wide range of drug sustained release applications.

[0005] This invention provides a photoresponse polymer capsule, characterized by comprising:

[0006] 1.1. Photoresponsive polymer shell: This shell is sensitive to light and can undergo reversible structural changes under light exposure. These changes can include contraction, expansion, or the formation and closure of pores, enabling precise control over the capsule structure.

[0007] 1.2. Drug core: Located inside the photoelectro-responsive polymer shell, it interacts with the shell to achieve controlled drug release.

[0008] Preparation method: This invention also provides a method for preparing photoresponsive polymer capsules, comprising the following steps:

[0009] 1. Prepare a mixture of N-isopropylacrylamide (Nipam) and waterborne polyurethane (PU) with a concentration ratio of 1:1, and sonicate for 30 minutes.

[0010] 2. Use a pipette to transfer 0.6ml-1ml of the mixture into the mold and irradiate with a UV lamp for about 10 minutes.

[0011] 3. Add the drug core to the capsule shell to form a mixture.

[0012] 4. Use a pipette to transfer 0.5 ml of the Nipam / PU mixed solution onto a flat surface, and irradiate with a UV lamp for about 10 minutes to obtain a Nipam / PU film.

[0013] 5. Adhere the Nipam / PU membrane and the capsule shell sample containing the mixed drug core together with Nipam / PU, and then irradiate it under a UV lamp for about 5 minutes until the capsule shell and the membrane adhere together.

[0014] 6. Place the prepared capsules in a dry environment (25℃) and let them stand for about 30 minutes to obtain the final product.

[0015] Preferably, the drug core can be in one of the following forms: solid, liquid, or semi-solid. The specific type and properties of the drug can be selected according to actual needs.

[0016] Preferably, the photoelectric responsive polymer shell structure can be precisely controlled by adjusting the irradiation time of ultraviolet or visible light.

[0017] Preferably, a crosslinking agent can be added to the mixture of Nipam and waterborne polyurethane to enhance the stability of the photoresponsive polymer shell.

[0018] The advantages of this invention are:

[0019] The photoelectroresponsive polymer capsules of this invention enable highly controllable drug release under light irradiation, offering advantages such as precision, reversibility, and adjustability. The preparation method is simple and effective, suitable for various drug sustained-release requirements. Attached Figure Description

[0020] Figure 1 This invention discloses a drug release mechanism diagram for a photoelectric responsive polymer capsule used for sustained drug release.

[0021] Figure 2 This is a flowchart of the preparation process of a photoelectroresponsive polymer capsule for drug sustained release disclosed in this invention. Detailed Implementation

[0022] The present invention will be further illustrated below with reference to the accompanying drawings and specific embodiments. These embodiments are implemented based on the technical solutions of the present invention, and it should be understood that these embodiments are only used to illustrate the present invention and are not intended to limit the scope of the present invention.

[0023] This embodiment presents a photoelectroresponsive polymer capsule for drug sustained release and its preparation method. The preparation process is as follows: Figure 2 The specific preparation steps are as follows:

[0024] Step S01: Prepare a mixture of N-isopropylacrylamide (Nipam) and waterborne polyurethane (PU) with a concentration of 5 μg / ml and a concentration ratio of 1:1, and sonicate for 30 min.

[0025] Step S02: Use a pipette to transfer 0.6ml-1ml of the mixture into the mold and irradiate it with a UV lamp for about 10 minutes;

[0026] Step S03: Add the drug core to the capsule shell to form a mixture.

[0027] Step S04: Use a pipette to transfer 0.5 ml of a 5 μg / ml Nipam / PU mixed solution onto a flat surface, and irradiate with a UV lamp for about 10 minutes to obtain a Nipam / PU membrane.

[0028] Step S05: Adhere the Nipam / PU membrane and the capsule shell sample containing the mixed drug core together with Nipam / PU, and then irradiate it under a UV lamp for about 5 minutes until the capsule shell and the membrane adhere together.

[0029] Step S06: Place the prepared capsules in a dry environment (25°C) and let them stand for 30 minutes to obtain the final product.

[0030] The photoelectric responsive polymer capsule prepared through the above steps has the following characteristics:

[0031] The photosensitive polymer capsule for drug sustained release prepared by the process described in this embodiment has a photosensitive polymer shell that is sensitive to light and can undergo reversible structural changes under light irradiation. These changes can include contraction, expansion, or the formation and closure of pores, enabling precise control over the capsule structure. The capsule is prepared at a wavelength of 365 nm and a light intensity of 20 mW / cm². 2 Under light irradiation, drug release reaches over 90% after 5 hours, and virtually no further drug release occurs after 20 hours. Furthermore, after the light is removed, the pores created by light exposure close, and drug release from the capsule ceases.

[0032] The above description is merely a preferred embodiment of the present invention. It should be noted that for those skilled in the art, other parts not specifically described are existing technology or common knowledge. 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 photoelectro-responsive polymer capsule, characterized in that it comprises: 1.

1. Photoelectro-responsive polymer shell, which is sensitive to light and can undergo reversible structural changes under light conditions. 1.

2. The drug core is located inside the photoelectro-responsive polymer shell and interacts with the shell to achieve controlled drug release.

2. The photoresponsive polymer capsule of claim 1, wherein, The photoelectro-responsive polymer shell exhibits responsiveness to light of different wavelengths.

3. The photoresponsive polymer capsule of claim 1, wherein, The structural changes of the photoelectroresponsive polymer shell include contraction, expansion, or the formation and closure of pores.

4. The photoresponsive polymer capsule of claim 1, wherein, The drug core is in one of the following forms: solid, liquid, or semi-solid.

5. A method for preparing photoresponsive polymer capsules, comprising the following steps: 5.1 Prepare a mixture of N-isopropylacrylamide (Nipam) and waterborne polyurethane (PU) with a concentration ratio of 1:1, and sonicate for 30 min. 5.2 Use a pipette to transfer 0.6ml-1ml of the mixture into the mold and irradiate with a UV lamp for about 10 minutes. 5.3 Add the drug core to the capsule shell to form a mixture. 5.4 Use a pipette to transfer 0.5 ml of Nipam / PU mixed solution onto a flat surface and irradiate with a UV lamp for about 10 minutes. 5.5 Adhere the Nipam / PU membrane and the capsule shell sample containing the mixed drug core together with Nipam / PU, and then irradiate it under a UV lamp for about 5 minutes until the capsule shell and the membrane adhere together. 5.6 Place the prepared capsules in a dry environment (25°C) and let them stand for about 30 minutes to obtain the final product.

6. The method of claim 5, wherein, By adjusting the irradiation time of ultraviolet or visible light, the structure of the photoelectric responsive polymer shell can be precisely controlled.

7. The method of claim 5, wherein, A crosslinking agent can be added to the mixture of N-isopropylacrylamide (Nipam) and waterborne polyurethane (PU) to enhance the stability of the photoresponsive polymer shell.

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