Prussian Blue-Based Non-Spherical Photothermal Swimming Nanomotors and Preparation Method Thereof

Abstract

The present invention provides a non-spherical photothermal electrophoresis nanomotor based on Prussian blue and a preparation method thereof. The preparation method includes: ultrasonically dispersing mesoporous Prussian nanocubes (MPB) in solvent water 1, and under stirring conditions, dropping a water-soluble polymer dissolved in solvent water 2, adjusting the mixed pH value to weakly alkaline and maintaining the same stirring rate to continue stirring for more than 0.5 h, then dropping a polar organic solvent, continuing to stir at the same rate for more than 0.5 h, dropping a silicon source TEOS, continuing to stir and react at room temperature at the same rate for more than 48 h, then centrifuging, washing and drying to obtain the target product. The raw materials of the present invention have low cost, and the prepared nanomotor has both high drug-loading capacity, photothermal therapy ability and photothermal-driven movement ability.

Description

Technical Field

[0001] The present invention belongs to the technical field of nanomotors, and relates to non-spherical photothermal electrophoresis nanomotors based on Prussian blue and a preparation method thereof. Background Art

[0002] A nanomotor is a micro / nano material capable of autonomous movement, which can convert the energy of the surrounding environment into autonomous movement. This ability enables it to exhibit unique application advantages and development prospects in application fields such as drug delivery, biomedicine, environmental remediation, and micro / nano engineering.

[0003] The propulsion mechanisms of nanomotors are mainly divided into three categories. The first category is bubble propulsion: bubbles are generated at the tail of the micro / nano motor through a catalytic reaction, and the reaction force of the bubbles is used to drive the motor forward, similar to rocket launch. The second category is self-phoresis: an asymmetric field is constructed around the motor through a chemical or physical reaction to trigger the flow of the surrounding fluid, and the flow of the fluid is used to push the motor. Among them, according to the different fields, self-phoresis can be further divided into self-electrophoresis, self-diffusiophoresis, self-thermophoresis, and self-phonophoresis. The third category is directly using microorganisms to drive micro / nano motors, which is called biological agent propulsion.

[0004] Photothermal electrophoresis-driven nanomotors usually use Janus nanoparticles. One side can perform photothermal conversion, while the other side has no photothermal conversion ability. When light is absorbed on the photothermal surface of such particles, a local temperature gradient is formed on the entire particle surface. This temperature gradient can generate a corresponding osmotic pressure gradient, thereby causing fluid flow at the interface between the particle and the solvent. For particles under uniform light stimulation, the particles will move along the rotational symmetry axis, so as to realize the rapid and accurate arrival of the photothermal-driven motor at the lesion site.

[0005] However, at present, most photothermal electrophoresis nanomotors are based on spherical and gold nanoparticles. From the perspective of morphology, their development is limited, and the spherical fluid resistance coefficient is relatively high, affecting the movement speed of the motor; from the perspective of materials, the raw material cost of gold nanoparticles is relatively high, affecting the industrialization development of the motor. Summary of the Invention

[0006] Aiming at the problems existing in the prior art, the present invention aims to provide non-spherical photothermal electrophoresis nanomotors based on Prussian blue and a preparation method thereof, with low raw material cost, and the prepared motors have high drug loading capacity, photothermal therapy ability, and photothermal-driven movement ability.

[0007] The technical solution adopted by the present invention to achieve the above technical purpose is as follows:

[0008] The present invention provides a method for preparing non-spherical photothermal electrophoresis nanomotors based on Prussian blue, including:

[0009] Ultrasonically disperse mesoporous Prussian nanocubes (MPB) in solvent water 1. Under stirring conditions, dropwise add a water-soluble polymer dissolved in solvent water 2. Adjust the mixed pH value to weakly alkaline and continue stirring at the same stirring rate for more than 0.5 h. Then, dropwise add a polar organic solvent and continue stirring at the same rate for more than 0.5 h. Next, dropwise add the silicon source TEOS and continue stirring at room temperature at the same rate for more than 48 h. After centrifugation, washing, and drying, the target product is obtained.

[0010] Preferably, the molar ratio of MPB, water-soluble polymer, and TEOS is 26.63:1:102.51; the concentration of MPB dispersed in solvent water 1 is 2 mg / mL, and the concentration of the water-soluble polymer dissolved in solvent water 2 is 0.5 g / mL; the volume ratio of solvent water 1 to the polar organic solvent is 1:(8 - 18).

[0011] Preferably, the water-soluble polymer mainly includes polyamides such as polyacrylamide and polybutenamide, and polyacids such as polyvinyl acid and polyacrylic acid.

[0012] Preferably, the polar organic solvent includes ketones, alcohols, pyridines, etc.

[0013] Preferably, ammonia water is used to adjust the pH value to be between 7.8 and 10.2.

[0014] Preferably, the stirring rate is 300 - 800 rpm.

[0015] The present invention also provides non-spherical photothermal electrophoresis nanomotors based on Prussian blue, which are prepared by the above preparation method.

[0016] Preferably, the nanomotors perform photothermal-driven motion under 808 nm near-infrared light irradiation.

[0017] The beneficial effects of the present invention are as follows:

[0018] The present invention breaks away from the traditional situation of spherical and Au-based photothermal electrophoresis nanomotors. Using Prussian blue nanoparticles as the photothermal conversion part and mesoporous silica as the non-photothermal conversion part, non-spherical and asymmetric nanomotors are prepared by the microemulsion method. This material can perform photothermal-driven motion under 808 nm near-infrared light irradiation, changing the current situation of photothermal electrophoresis motors mainly based on Janus spherical nanoparticles. At the same time, the photothermal part is changed from the commonly used gold nanomaterial to Prussian blue, and the raw material cost is lower. The prepared motors have high drug-loading capacity, photothermal therapy ability, and photothermal-driven motion ability, realizing multi-functional integration. Description of the Drawings

[0019] Figure 1 SEM results of the nanomotors prepared in the embodiments of the present invention.

[0020] Figure 2 Motion diagram of the nanomotors prepared in the embodiments of the present invention under a two-photon fluorescence confocal microscope.

[0021] Figure 3 Photothermal conversion ability of the nanomotors prepared in the examples of the present invention. Detailed implementation manners

[0022] To illustrate the present invention more clearly, the present invention will be further described in detail below in conjunction with embodiments and with reference to the accompanying drawings. Those skilled in the art should understand that the specific content described below is illustrative rather than restrictive, and should not be used to limit the protection scope of the present invention.

[0023] Embodiment

[0024] The preparation method of the non-spherical photothermal nanomotors based on Prussian blue in this embodiment is as follows:

[0025] Preparation of mesoporous Prussian nanocubes (MPB): Specifically, 300 mg of potassium ferricyanide (K3[Fe(CN)6]) solid and 6 g of polyvinylpyrrolidone (PVP) are dissolved in 40 mL of dilute hydrochloric acid (0.01 M), and stirred at a speed of 500 rpm at room temperature until clear and transparent. The solution is transferred to a stainless steel polytetrafluoroethylene reaction kettle and reacted at 80 °C for 24 h. After cooling, it is centrifuged at 10,000 rpm for 30 min, washed several times with deionized water and ethanol, and dried overnight at 60 °C in a vacuum oven to obtain mesoporous Prussian blue (MPB) nanocubes.

[0026] Weigh 20 mg of mesoporous Prussian nanocubes (MPB) and ultrasonically disperse them in 10 mL of water at a frequency of 100 KHz. Under the stirring condition of a rate of 500 rpm, 70 μL of an aqueous solution of polyacrylamide with a concentration of 0.5 g / mL is added dropwise. After adjusting the pH value of the mixed solution to 8.5 with ammonia water, stirring continues for 1 h. Then 100 mL of acetone solvent is added dropwise, and after stirring for 1 h, 20 μL of TEOS is added dropwise. After stirring and reacting at room temperature for 48 h, it is centrifuged at a rate of 12,000 rpm for 20 min. After washing 3 times with deionized water and ethanol, it is vacuum dried at 40 °C for 12 h to obtain the target product.

[0027] The SEM results of the nanomotors are shown in Figure 1 , and the results show that the material presents a conjoined non-spherical shape, about 100 nm in length and about 50 nm in width.

[0028] The motion diagram of the nanomotors under a two-photon fluorescence confocal microscope is shown in Figure 2, The results show that the material can move effectively under the irradiation of 808 nm NIR light. According to the statistical calculation of the software, the total moving distance reaches 843 μm within 20 s, and the average speed is 42 μm / s. Without NIR light irradiation, the motor mainly makes irregular Brownian motion nearby and basically does not move far from its original area.

[0029] The drug-loading capacity of the nanomotor loaded with doxorubicin (DOX) was measured by ultraviolet-visible spectrophotometry, as shown in Table 1. The results show that the material has a high drug-loading capacity, and each milligram of the motor can load 714.52 μg of DOX.

[0030] Table 1 Absorbance and drug-loading capacity results of residual DOX after the motor is loaded with drugs

[0031]

[0032] The near-infrared photothermal conversion ability of the nanomotor is shown in Figure 3 , The results show that for an aqueous solution of the motor with a concentration of 500 μg / mL, after being irradiated with 808 nm near-infrared light (NIR) with a power of 2 W / cm 2 for 2.5 min, the motor can be heated from room temperature to 64.2 °C, proving that it has good photothermal conversion ability and potential photothermal therapy ability.

[0033] Obviously, the above-mentioned embodiments of the present invention are merely examples for more clearly explaining the present invention, rather than limitations on the implementation manners of the present invention. For those of ordinary skill in the art, based on the above description, other different forms of changes or modifications can be made. It is impossible to list all the implementation methods here. Any obvious changes or modifications derived from the technical solutions of the present invention still fall within the protection scope of the present invention.

Claims

1. Preparation method of non-spherical photothermal electrophoresis nanomotor based on Prussian blue, comprising: Ultrasonically disperse mesoporous Prussian nanocubes MPB in solvent water 1. Under stirring conditions, dropwise add a water-soluble polymer dissolved in solvent water 2. Adjust the mixed pH value to weakly alkaline and continue stirring at the same stirring rate for more than 0.5 h. Then, dropwise add a polar organic solvent and continue stirring at the same rate for more than 0.5 h. Next, dropwise add the silicon source TEOS and continue stirring at room temperature at the same rate for a reaction for more than 48 h. After centrifugation, washing, and drying, the target product is obtained; both solvent water 1 and solvent water 2 are water, and the water-soluble polymer is polyacrylamide.

2. The preparation method of the non-spherical photothermal electrophoresis nanomotor based on Prussian blue according to claim 1, characterized in that The molar ratio of MPB, water-soluble polymer, and TEOS is 26.63:1:102.51; the concentration of MPB dispersed in solvent water 1 is 2 mg / mL, and the concentration of the water-soluble polymer dissolved in solvent water 2 is 0.5 g / mL; the volume ratio of solvent water 1 to the polar organic solvent is 1:8 - 18.

3. The preparation method of the non-spherical photothermal electrophoresis nanomotor based on Prussian blue according to claim 1, characterized in that The polar organic solvent includes ketones, alcohols, and pyridines.

4. The preparation method of the non-spherical photothermal electrophoresis nanomotor based on Prussian blue according to claim 1, characterized in that Adjust the pH value to be between 7.8 and 10.2 using ammonia water.

5. The preparation method of the non-spherical photothermal electrophoresis nanomotor based on Prussian blue according to claim 1, characterized in that, The stirring rate is 300 - 800 rpm.

6. Non-spherical photothermal electrophoresis nanomotor based on Prussian blue, prepared by the preparation method of the non-spherical photothermal electrophoresis nanomotor based on Prussian blue according to any one of claims 1 - 5.

7. The non-spherical photothermal electrophoresis nanomotor based on Prussian blue according to claim 6, wherein The nanomotor undergoes photothermal-driven motion under 808 nm near-infrared light irradiation.

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