Hydrophobic temperature-sensitive mesoporous silica drug delivery system and preparation method and application thereof

Abstract

The application discloses a hydrophobic temperature-sensitive mesoporous silica drug delivery system and a preparation method and application thereof, and the drug delivery system takes copper sulfide nanoparticles as a core, takes amino-modified hydrophobic mesoporous silica as a shell, and is coated with a surface coating of a temperature-sensitive polymer PEG-p(AAm-co-AN), wherein the hydrophobic mesoporous silica is prepared from silane coupling agent A151 containing a carbon-carbon double bond and a silicon source TEOS; the drug delivery system has photothermal effect and upper critical solution temperature responsiveness, can load a large amount of hydrophobic drugs such as beta-elemene, and can realize controllable release under 980nm near-infrared light irradiation. The phase transition temperature of the delivery system is 43 DEG C, so that the combination of photothermal therapy and chemotherapy can be realized while the drug release is controlled, so as to achieve more effective tumor inhibition. In addition, the preparation method is simple and has wide application prospect.

Description

TECHNICAL FIELD

[0001] The present application belongs to the field of drug delivery systems, and particularly relates to a hydrophobic temperature-sensitive mesoporous silica drug delivery system and a preparation method and application thereof. BACKGROUND

[0002] In recent years, nanodrug delivery systems have made significant progress in the field of tumor treatment, especially mesoporous silica nanoparticles (MSNs) have become ideal drug carriers due to their unique physical and chemical properties, such as large specific surface area, rich pore structure, good biocompatibility, and easy surface modification. However, traditional mesoporous silica nanoparticles have some shortcomings in drug delivery, such as premature drug leakage and easy clearance in blood circulation. In addition, tumor cells have a high metabolic rate, and their microenvironment is significantly different from that of normal cells, such as higher temperature and higher glutathione concentration, but traditional drug carriers often fail to fully utilize these differences to achieve precise treatment. For example, the hydrophilic pores of traditional MSNs are difficult to effectively adsorb hydrophobic chemotherapeutic drugs, resulting in low drug loading efficiency.

[0003] At present, temperature-sensitive polymer modified mesoporous silica nanoparticles have shown good application prospects in drug delivery. By coating hollow mesoporous silica nanoparticles with temperature-sensitive polymers, temperature-stimulated release of drugs can be achieved. However, this type of system still needs further optimization in terms of drug loading stability, release rate control, and responsiveness to tumor microenvironment.

[0004] As a new emerging treatment method, the photothermal-driven drug release strategy can achieve controllable release of drugs through photothermal effect, and change the tumor microenvironment through local hyperthermia to promote drug absorption. However, the strong absorption and scattering of light by biological tissues limit the treatment depth of the photothermal drug release strategy, and there is a lack of effective monitoring means for photothermal temperature and drug release dose. In addition, some "gatekeeper" molecules used to control drug release have limitations such as cytotoxicity and difficulty in degradation in vivo, which restrict their further application.

[0005] In summary, developing a new drug delivery system that can effectively combine photothermal effect, temperature-sensitive response, and tumor microenvironment specificity is of great significance for improving the effectiveness of tumor treatment. SUMMARY

[0006] The present application aims to overcome the shortcomings of the prior art and provide a hydrophobic temperature-sensitive mesoporous silica drug delivery system and a preparation method and application thereof.

[0007] To achieve the above-mentioned purpose, the present application adopts the following technical solutions:

[0008] In a first aspect, the present application provides a hydrophobic temperature-sensitive mesoporous silica drug delivery system, which can load a large amount of hydrophobic chemotherapeutic drugs and control the timed and targeted release of the drugs, and when the near-infrared light driven system is warmed to above 43 DEG C, the original collapsed surface phase changes to an expanded state, opening the mesoporous channels to release the drugs and avoid premature leakage of the drugs. At the same time, the system contains a photothermal agent, which can realize photothermal therapy under the driving of near-infrared light.

[0009] Specifically, the drug delivery system sequentially from inside to outside is: a photothermal core, a hydrophobic layer, and a temperature-sensitive layer; wherein the photothermal core is copper sulfide nanoparticles CuS NPs; the hydrophobic layer is mesoporous silica with hydrophobic pores, and the surface is modified with amino groups; the temperature-sensitive layer is PEG-p(AAm-co-AN); the mesoporous silica with hydrophobic pores is obtained by reacting tetraethyl orthosilicate TEOS and triethoxysilane vinyl silane A151.

[0010] The A151 used in the present application contains carbon-carbon double bonds, which can create a hydrophobic environment to load hydrophobic drugs, and a large number of A151 hinges can form a large number of hydrophobic cavities, and the hydrophobic interaction can improve the drug loading performance of the hydrophobic drugs; in addition, the carbon-carbon double bonds in A151 can also undergo click chemistry reaction with the mercapto group in beta-mercaptoethylamine to realize amino modification of the silica nanoparticles.

[0011] In a second aspect, the present application provides a preparation method of the above-mentioned hydrophobic temperature-sensitive mesoporous silica drug delivery system, which comprises the following steps:

[0012] Step (1), preparing copper sulfide nanoparticles CuS NPs.

[0013] Step (2), preparing CuS@HMS NPs:

[0014] Mixing cetyltrimethylammonium bromide CTAB, triethanolamine TEA and copper sulfide nanoparticles CuS NPs, adding tetraethyl orthosilicate TEOS and then reacting, and then adding triethoxysilane vinyl silane A151 to continue the reaction to obtain CuS@HMS NPs;

[0015] Step (3), amino modification of CuS@HMS NPs:

[0016] Mixing CuS@HMS NPs with beta-mercaptoethylamine and azobisisobutyronitrile AIBN, purging nitrogen to remove oxygen, and water bath synthesis of C@HM NPs with amino groups on the surface;

[0017] Step (4), preparing PEG-p(AAm-co-AN):

[0018] The acrylamide, acrylonitrile and azobis cyanovaleric acid are dissolved in dimethyl sulfoxide, mixed and heated to react under nitrogen to remove oxygen, to obtain poly(acrylamide-acrylonitrile) p(AAm-co-AN); then the p(AAm-co-AN) is mixed with methoxypolyethylene glycol succinimidyl carbonate PEG-SC, dissolved in anhydrous dimethyl sulfoxide to react to obtain PEG-p(AAm-co-AN);

[0019] Step (5), preparation of hydrophobic temperature-sensitive mesoporous silica C@HM@PNPs:

[0020] The PEG-p(AAm-co-AN), 1-ethyl-(3-dimethylaminopropyl) carbodiimide EDC and N-hydroxysuccinimide NHS are mixed and reacted under stirring, then the anhydrous dimethyl sulfoxide solution of C@HM NPs is added, oxygen is removed by nitrogen, and the hydrophobic temperature-sensitive mesoporous silica C@HM@PNPs are obtained after reaction.

[0021] As preferred, the copper sulfide nanoparticles CuS NPs in step (1) are prepared by the following method: cetyltrimethylammonium bromide CTAB and CuCl2·2H2O are dissolved in water and stirred, then Na2S·9H2O is added to react in water bath, and CuS NPs aqueous solution is obtained after cooling; the molar ratio of CTAB, CuCl2·2H2O and Na2S·9H2O is 1-5:2:2, more preferably 1:2:2.

[0022] As preferred, the molar ratio of CTAB, TEA, TEOS and A151 in step (2) is 10:1:3-3.3:4-10, more preferably 10:1:3.2-3.3:5; by adjusting the ratio of TEOS and A151, a nano delivery system with high drug loading capacity for hydrophobic drugs can be obtained.

[0023] As preferred, the mass ratio of CuS@HMS NPs, β-mercaptoethylamine and AIBN in step (3) is 4:1-15:1, more preferably 4:2:1.

[0024] As preferred, the molar ratio of acrylamide, acrylonitrile and azobis cyanovaleric acid in step (4) is 1:0.2-0.6:0.01, more preferably 1:0.3:0.01.

[0025] As preferred, the mass ratio of PEG-SC and p(AAm-co-AN) in step (4) is 1.2-1.5:1, more preferably 1.32:1.

[0026] Preferably, the mass ratio of PEG-p(AAm-co-AN), C@HM NPs, EDC, and NHS in step (5) is 1:2:0.02-0.1:0.01-0.1, more preferably 1:2:0.023:0.013.

[0027] In a third aspect, the present application provides the use of the above-mentioned hydrophobic temperature-sensitive mesoporous silica drug delivery system in loading a chemotherapeutic drug. The delivery system creates a hydrophobic mesoporous environment, which can use hydrophobic interaction to drive the hydrophobic chemotherapeutic drug, such as β-elemene, docetaxel, doxorubicin, etc., to actively enter the hydrophobic pore of the temperature-sensitive mesoporous silica, so as to achieve the goal of high loading efficiency.

[0028] Preferably, the mass ratio of the hydrophobic temperature-sensitive mesoporous silica drug delivery system and the chemotherapeutic drug is 1:1-10, more preferably 1:7.5.

[0029] In a fourth aspect, the present application provides the use of the above-mentioned hydrophobic temperature-sensitive mesoporous silica drug delivery system in preparing a tumor photothermal therapy synergistic chemotherapeutic drug, and the tumor is breast cancer.

[0030] Compared with the prior art, the present application has the following beneficial technical effects:

[0031] The present application combines the photothermal effect, temperature-sensitive response, and the characteristics of the tumor microenvironment, uses mesoporous silica containing hydrophobic pores as the framework, wraps the polymer polyethylene glycol-poly(acrylamide-acrylonitrile) outer cover with an upper critical solution temperature response, and uses the photothermal agent CuS NPs as the core. Near-infrared light irradiation drives CuS NPs to convert light energy into heat energy, causing the temperature of the particles themselves and the surrounding environment to rapidly rise, and the polyethylene glycol-poly(acrylamide-acrylonitrile) outer cover is opened as a temperature-responsive switch. In addition, high temperature can promote the intensification of molecular thermal motion, and a large amount of drugs in the hydrophobic pore are released, realizing chemotherapy. At the same time, high temperature can cause damage to tumor cells, realizing the combined treatment of photothermal therapy and chemotherapy, which can overall reduce the dosage of the chemotherapeutic drug, reduce the side effects of chemotherapy and alleviate drug resistance, and improve the anti-tumor effect. This multiple stimulus response can more accurately release drugs at the tumor site, reducing drug leakage in normal tissues.

[0032] The present application prepares silica nanoparticles containing hydrophobic mesoporous pores, which ingeniously uses hydrophobic interaction to improve the drug loading capacity, and the preparation method is simple, the loading effect is remarkable, and can effectively load hydrophobic drugs, such as β-elemene, docetaxel, or doxorubicin, etc.

[0033] The temperature-sensitive layer of the present application selects PEG-p(AAm-co-AN), which has a simple preparation method and high stability, and has temperature response characteristics, and the upper critical solution temperature (UCST) thereof can be regulated by adjusting the ratio of acrylonitrile (AN) and acrylamide (AAm) in the copolymer. When the local temperature is increased to above the UCST due to the photothermal effect, the polymer chain is hydrophilic and stretched, the drug is quickly released, on-demand drug delivery is achieved, and systemic toxicity is reduced. BRIEF DESCRIPTION OF DRAWINGS

[0034] Figure 1 Fig. 1 is a characterization image and performance test result of CuS NPs, wherein A) is a transmission electron microscopy image, B) is a particle size distribution graph, C) is an ultraviolet-visible-near infrared absorption curve, and D) is a photothermal conversion curve (980 nm, 2 W / cm 2 );

[0035] Figure 2 Fig. 2 is a transmission electron microscopy image of nanoparticles, wherein A) is CuS@HMS NPs, B) is C@HM NPs, and C) is C@HM@P NPs;

[0036] Figure 3 Fig. 3 is a Raman spectrum of CuS@HMS NPs and C@HM NPs;

[0037] Figure 4 Fig. 4 is a Zeta-potential graph of CuS NPs, CuS@HMS NPs, C@HM NPs, Template Removed C@HM NPs, PEG-p(AAm-co-AN), and C@HM@P NPs;

[0038] Figure 5 Fig. 5 is a transmittance result graph of PEG-p(AAm-co-AN) aqueous solution with temperature change;

[0039] Figure 6 Fig. 6 is a cell survival rate after C@HM@P NPs of different concentrations were co-incubated with 4T1 cells;

[0040] Figure 7 Fig. 7 is an in vitro efficacy evaluation graph of C@HM@P-β-ELE NPs, wherein A) is the effect of different β-ELE concentrations on cell survival rate, and B) is the cell survival rate under different treatment conditions. DETAILED DESCRIPTION

[0041] In order to make the technical problems, technical solutions and advantages to be solved by the present application more clear, the following will be described in detail in combination with the drawings and specific embodiments.

[0042] Example 1:

[0043] Take 8.5mg CuCl2and 10mg of CTAB, add 40mL water to it, stir for 20min at room temperature. Then add 12.1mg Na2S to the above solution and continue stirring for 5min, then transfer to a water bath heated at 90°C for 15min. The ink green solution obtained after ice bath cooling is CuS-CTAB NPs solution.

[0044] Example 2:

[0045] Take 8.5mg CuCl2and 50mg of CTAB, add 40mL water to it, stir for 20min at room temperature. Then add 12.1mg Na2S to the above solution and continue stirring for 5min, then transfer to a water bath heated at 90°C for 15min. The ink green solution obtained after ice bath cooling is CuS-CTAB NPs solution.

[0046] Example 3:

[0047] Mix 0.5g CTAB, 18ul TEA and 20ml CuS-CTAB NPs solution obtained in Example 1 at room temperature for 1h, then add 100ul TEOS, stir at 90°C for 30min, then add 150ul A151, stir at 90°C for 1h, cool to room temperature. Then centrifuge at 11000rpm / min for 5min, wash with methanol for 3 times to collect CuS@HMS NPs.

[0048] Example 4:

[0049] Mix 0.5g CTAB, 18ul TEA and 20ml CuS-CTAB NPs solution obtained in Example 1 at room temperature for 1h, then add 100ul TEOS, stir at 90°C for 30min, then add 125ul A151, stir at 90°C for 1h, cool to room temperature. Then centrifuge at 11000rpm / min for 5min, wash with methanol for 3 times to collect CuS@HMS NPs.

[0050] Example 5:

[0051] Take 120 mg CuS@HMS NPs in Example 3, 60 mg β-mercaptoethylamine, 30 mg AIBN into 72 ml anhydrous ethanol, remove O2 in the system by passing N2 for 15 min, and carry out the free radical addition reaction in an oxygen-free environment. The reaction is continued for 12 h under mechanical stirring at 70 °C water bath, and after the end of the reaction, it is cooled to room temperature and centrifuged at 11000 rpm / min for 10 min. The product is washed with methanol for three times, and then re-dispersed into 12.5 ml methanol, 100 mg sodium chloride is added, and it is magnetically stirred at room temperature for 24 h. After the end of the reaction, it is centrifuged at 10000 rpm / min for 5 min, and washed with methanol for three times. Such operation is repeated for three times, and finally the product is collected to obtain C@HM NPs.

[0052] Example 6:

[0053] Take 120 mg CuS@HMS NPs in Example 3, 60 mg β-mercaptoethylamine, 30 mg AIBN into 72 ml anhydrous ethanol, remove O2 in the system by passing N2 for 15 min, and carry out the free radical addition reaction in an oxygen-free environment. The reaction is continued for 12 h under mechanical stirring at 70 °C water bath, and after the end of the reaction, it is cooled to room temperature and centrifuged at 11000 rpm / min for 10 min. The product is washed with methanol for three times, and then re-dispersed into 12.5 ml methanol, 100 mg sodium chloride is added, and it is magnetically stirred at room temperature for 24 h. After the end of the reaction, it is centrifuged at 10000 rpm / min for 5 min, and washed with methanol for three times. Such operation is repeated for three times, and finally the product is collected to obtain C@HM NPs.

[0054] Example 7:

[0055] Accurately weigh 6.39 g of acrylamide and 292.67 mg of azobis cyanovaleric acid into 120 ml of anhydrous dimethyl sulfoxide, inject 1.8 ml of acrylonitrile, and mix thoroughly. After passing N2 for 20 min, it is transferred to a 60 °C water bath for heating for 6 h. After the end of the reaction, it is quickly transferred to an ice water bath for cooling, and then slowly poured into 900 ml of methanol to precipitate the polymer. The methanol solution containing the precipitate is placed in a -80 °C environment overnight to precipitate the polymer. The supernatant is poured out, and the remaining methanol solution containing the precipitate is centrifuged at 8000 rpm / min for 5 min. The obtained precipitate is washed with methanol for six times to sufficiently wash away the residual DMSO. Finally, the product is vacuum freeze-dried to obtain a white powder, which is p(AAm-co-AN). Accurately weigh 10 mg of p(AAm-co-AN) and 13.2 mg of PEG-SC into 4 ml of anhydrous dimethyl sulfoxide, and stir at 50 °C water bath for 24 h. After that, it is dialyzed with ultrapure water for 48 h, and finally the obtained white solid after vacuum freeze-drying is PEG-p(AAm-co-AN).

[0056] Example 8:

[0057] Precisely weigh 6.39 g of acrylamide and 292.67 mg of azobis cyanovaleric acid into 120 ml of anhydrous dimethyl sulfoxide, inject 2.0 ml of acrylonitrile, and mix thoroughly. After 20 min of N2, transfer to a 60°C water bath for 6 h. After the reaction is completed, quickly transfer to an ice water bath for cooling, then slowly pour into 900 ml of methanol to precipitate the polymer. The methanol solution containing the precipitate is placed in a -80°C environment overnight to precipitate the polymer. Pour out part of the supernatant, and centrifuge the remaining methanol solution containing the precipitate at 8000 rpm / min for 5 min. Wash the obtained precipitate with methanol six times to thoroughly wash away the residual DMSO. Finally, vacuum freeze-dry the product to obtain a white powder, which is p(AAm-co-AN). Precisely weigh 10 mg of p(AAm-co-AN) and 13.2 mg of PEG-SC into 4 ml of anhydrous dimethyl sulfoxide, and stir at 50°C for 24 h. Then, dialyze with ultrapure water for 48 h, and finally vacuum freeze-dry the obtained white solid to obtain PEG-p(AAm-co-AN).

[0058] Example 9:

[0059] Weigh 90 mg of PEG-p(AAm-co-AN) in Example 7 into 60 ml of anhydrous dimethyl sulfoxide to prepare a 1.5 mg / ml solution, then add 2.13 ml of EDC-DMSO solution with a concentration of 1 mg / ml and 1.2 ml of NHS-DMSO solution with a concentration of 1 mg / ml dropwise into the solution, respectively. Transfer the mixed solution to a 50°C water bath for reaction for 30 min. At the same time, take 180 mg of C@HM NPs obtained in Example 5, dissolve in 15 ml of anhydrous dimethyl sulfoxide to prepare a solution with a concentration of 12 mg / ml. After 30 min of reaction of PEG-p(AAm-co-AN), completely inject the just prepared C@HM solution, pass N2 for 10 min, and then continue to react at 50°C for 24 h. Finally, transfer the reaction completed solution to a dialysis bag and dialyze with ultrapure water for 48 h. Vacuum freeze-dry to obtain C@HM@PNPs powder.

[0060] Example 10:

[0061] Weigh 3 mg of C@HM@PNPs powder from Example 9 and dissolve it in 5 ml of anhydrous ethanol, then add 22.5 mg of β-elemene. Transfer the mixture to a 50°C water bath and stir in the dark for 24 h to fully load β-elemene into the C@HM@PNPs. After loading, centrifuge at 11000 rpm / min for 5 min, collect the precipitate, and wash twice with anhydrous ethanol to remove drug residues on the surface of the drug-loaded nanoparticles C@HM@P-β-ELE.

[0062] Example 11:

[0063] Weigh 3 mg of C@HM@PNPs powder from Example 9 and dissolve it in 5 ml of anhydrous ethanol, then add 30 mg of β-elemene. Transfer the mixture to a 50°C water bath and stir in the dark for 24 h to fully load β-elemene into the C@HM@PNPs. After loading, centrifuge at 11000 rpm / min for 5 min, collect the precipitate, and wash twice with anhydrous ethanol to remove drug residues on the surface of the drug-loaded nanoparticles C@HM@P-β-ELE.

[0064] Examples 1, 3, 5, 7, 9, 10 and 11 were characterized.

[0065] from Figure 1 A and Figure 1 As can be seen from B in Example 1, the CuS-CTAB NPs prepared in Example 1 are uniformly dispersed, with uniform particle size and a hydrated particle size of 17.40±1.92nm. Figure 1 The UV-Vis-NIR absorption results of C in CuS-CTAB NPs aqueous solution show that there is a strong absorption characteristic peak at 980 nm. Figure 1 The D-values ​​in the data show that CuS-CTAB NPs do indeed exhibit superior photothermal conversion capabilities compared to aqueous solutions.

[0066] exist Figure 2 In the TEM results of AC, CuS@HMSNNPs, C@HM NPs, and C@HM@PNPs in Examples 3, 5, and 9 are all spherical particles with a complete core-shell structure and a particle size of 50-60 nm. Furthermore, there is no significant difference in morphology among the three, possibly because the amino-modified layer is extremely thin, and the upper critical solution temperature responsive polymer shell is in a collapsed state at room temperature, making it impossible to observe in TEM. The morphological comparison of the three nanoparticles also demonstrates that neither amino modification nor encapsulation of the upper critical solution temperature responsive polymer significantly increases the particle size of CuS@HMSN NPs, nor does it disrupt the uniform dispersion of the nanoparticles. That is, this method can obtain stable C@HM@PNPs.

[0067] Figure 3To characterize the Raman spectra of CuS@HMS NPs and C@HM NPs in Examples 3 and 5. Compared with the fingerprint spectrum of CuS@HMS NPs, the spectrum of C@HM NPs appeared a stretching vibration peak of -CH2-S- at 523 cm -1

[0068] Figure 4 The Zeta-potential of nanoparticles in Examples 1, 3, 5, 7, 9 was characterized. The potential of CuS@HMSN NPs decreased slightly after being modified by amino groups, but it was still positively charged. After washing the positively charged CTAB template, C@HM NPs were negatively charged, and were linked to PEG-p(AAm-co-AN) which was also negatively charged through amide bonds, obtaining C@HM@PNPs with a Zeta-potential of -24.84 ± 0.51 mV.

[0069] Figure 5 is the critical temperature determination result of the upper critical solution temperature responsive polymer PEG-p(AAm-co-AN) in Example 7. The phase transition of PEG-p(AAm-co-AN) is reflected in the change of the transmittance of its aqueous solution. When the temperature rises to 43℃, the transmittance of PEG-p(AAm-co-AN) almost approaches 100%, and remains stable, indicating that the temperature-sensitive polymer PEG-p(AAm-co-AN) with an upper critical solution temperature of 43℃ is successfully synthesized in Example Seven.

[0070] The drug loading and encapsulation efficiency of C@HM@PNPs in Examples 10 and 11 can reach the following results: C@HM@P:β-ELE = 1:7.5, drug loading 81.32 ± 0.08%, encapsulation efficiency 58.04 ± 0.32%; C@HM@P:β-ELE = 1:10, drug loading 81.23 ± 0.67%, encapsulation efficiency 43.31 ± 1.87%.

[0071] The cytotoxicity of Example 9 was tested and evaluated by MTT method.

[0072] After 4T1 cells were inoculated in a 96-well plate and placed in an incubator, different concentrations of C@HM@P (0-600 μg / ml) were added to each well, and the plate was incubated in the incubator for 24 h. Then 33 μl of MTT solution (5 mg / ml) was added to each well, and incubated for 4 h. After removing the liquid in each well, 200 μl of dimethyl sulfoxide was added to each well, and the absorbance value at 570 nm was measured using an enzyme marker. The cell survival rate of each group was obtained by comparing the absorbance values of the experimental and control groups. ​

[0073] As Figure 6 shown, the experimental results show that even if the concentration of C@HM@P is 600 μg / mL, the cell viability is still greater than 80%, which proves that C@HM@P has good biological safety.

[0074] The in vitro anti-tumor effect of Example 10 was tested and evaluated by the MTT method.

[0075] First, 4T1 cells were inoculated in a 96-well plate and placed in an incubator for incubation, and after the cells grew to an appropriate density, they were co-incubated with different concentrations of free β-ELE and C@HM@P-β-ELE (β-ELE concentration was 0-300 μg / ml). For the laser group (Laser), after co-incubation for 4 h, the cells were irradiated with a laser for 5 min (980 nm, 2 w / cm 2 ), and incubated for another 20 h, then MTT solution (33 μl, 5 mg / ml) was added to each well, and after incubation for 4 h, the liquid in the well was removed, 100 μl of dimethyl sulfoxide was added, and the absorbance value at 570 nm was determined using an enzyme marker instrument, and finally the cell survival rate of each group was obtained. According to the results obtained, 7 groups of experiments were re-set, and the corresponding nanomaterials or drugs were added to each group in the same way, and the cell survival rates under different conditions were obtained.

[0076] The results are shown in A of Figure 7 When the concentration of β-ELE reached 80 μg / ml, the survival rate of 4T1 cells was less than 50%, and the cell survival rate of the C@HM@P-β-ELE+Laser group was even lower. B of Figure 7 proves that this result is caused by the synergistic effect of hyperthermia and chemotherapy drugs, which shows that C@HM@P-β-ELE NPs can achieve the synergistic effect of hyperthermia and chemotherapy, and achieve better anti-tumor effect.

[0077] The above only describes the embodiments of the present application and cannot be understood as limiting the scope of the present application. For those skilled in the art, the claims and drawings can be modified, innovated or applied to other technical fields, however, it should be noted that all modifications of the present application should be included in the patent protection scope of the present application.

Claims

1. A hydrophobic, temperature-sensitive mesoporous silica drug delivery system, characterized in that, The drug delivery system comprises, from the inside out: a photothermal core, a hydrophobic layer, and a thermosensitive layer; wherein, the photothermal core is copper sulfide nanoparticles CuS NPs; the hydrophobic layer is mesoporous silica with hydrophobic cavities and its surface is aminated; and the thermosensitive layer is PEG-p(AAm-co-AN). The mesoporous silica with hydrophobic cavities is obtained by reacting tetraethyl orthosilicate (TEOS) and triethoxyvinylsilane (A151). The hydrophobic, temperature-sensitive, mesoporous silica drug delivery system was prepared using the following method: Step (1): Preparation of CuS@HMSN NPs: A template agent, an alkaline catalyst, and copper sulfide nanoparticles (CuS NPs) were mixed, and then tetraethyl orthosilicate (TEOS) was added to initiate the reaction. Triethoxyvinylsilane (A151) was then added to continue the reaction, yielding CuS@HMSN NPs. The template agent was hexadecyltrimethylammonium bromide (CTAB), the alkaline catalyst was triethanolamine (TEA), and the molar ratio of the template agent, alkaline catalyst, TEOS, and A151 was 10:1:3~3.3:4~10. Step (2): Amide modification of CuS@HMSN NPs: CuS@HMSN NPs were mixed with β-mercaptoethylamine and azobisisobutyronitrile (AIBN), and nitrogen gas was introduced to remove oxygen. C@HM NPs with amino groups on the surface were synthesized in a water bath. Step (3): Preparation of hydrophobic temperature-sensitive mesoporous silicon C@HM@P NPs: PEG-p(AAm-co-AN), 1-ethyl-(3-dimethylaminopropyl)carbodiimide (EDC), and N-hydroxysuccinimide (NHS) were mixed and reacted under stirring. Then, an anhydrous dimethyl sulfoxide solution of C@HM NPs was added, and nitrogen gas was purged to remove oxygen. After the reaction, hydrophobic, temperature-sensitive mesoporous silica C@HM@P NPs were obtained. The PEG-p(AAm-co-AN) was prepared by dissolving acrylamide, acrylonitrile, and azodicyanovalerate in dimethyl sulfoxide, mixing, and purging with nitrogen gas to remove oxygen before heating to obtain poly(acrylamide-acrylonitrile). p(AAm-co-AN); then p(AAm-co-AN) is mixed with methoxy polyethylene glycol succinimide carbonate PEG-SC, dissolved in anhydrous dimethyl sulfoxide, and reacted to obtain PEG-p(AAm-co-AN); the molar ratio of acrylamide, acrylonitrile, and azodicyanovalerate is 1:0.2~0.6:0.

01.

2. The hydrophobic, temperature-sensitive mesoporous silica drug delivery system according to claim 1, characterized in that, The copper sulfide nanoparticles CuS NPs were prepared by the following method: hexadecyltrimethylammonium bromide (CTAB) and CuCl2·2H2O were dissolved in water and stirred, then Na2S·9H2O was added for a water bath reaction, and after cooling, an aqueous solution of CuS NPs was obtained; wherein the molar ratio of hexadecyltrimethylammonium bromide (CTAB), CuCl2·2H2O and Na2S·9H2O was 1~5:2:

2.

3. The hydrophobic, temperature-sensitive mesoporous silica drug delivery system according to claim 1, characterized in that, The mass ratio of CuS@HMSNNPs, β-mercaptoethylamine, and azobisisobutyronitrile (AIBN) is 4:1 to 15:

1.

4. The hydrophobic, temperature-sensitive mesoporous silica drug delivery system according to claim 1, characterized in that, The mass ratio of PEG-SC to p(AAm-co-AN) is 1.2~1.5:

1.

5. The hydrophobic, temperature-sensitive mesoporous silica drug delivery system according to claim 1, characterized in that, The mass ratio of PEG-p(AAm-co-AN), C@HM NPs, EDC, and NHS is 1:2:0.02~0.1:0.01~0.

1.

6. The application of the hydrophobic, temperature-sensitive mesoporous silica drug delivery system according to any one of claims 1-5 in the preparation of drugs loaded with chemotherapy agents, characterized in that... The chemotherapy drug is β-elemene, and the mass ratio of the hydrophobic thermosensitive mesoporous silica drug delivery system to the chemotherapy drug is 1:1~10.

7. The application of the hydrophobic thermosensitive mesoporous silica drug delivery system as described in claim 1 in the preparation of tumor photothermal therapy synergistic chemotherapy drugs.

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