A biomimetic targeting noble metal-based PLGA drug-carrying nanoparticle for lung cancer cell membranes, its preparation method and application

Abstract

This invention discloses a biomimetic targeted noble metal-based PLGA nanoparticle for lung cancer cell membranes, comprising a drug-loaded core and a lung cancer cell membrane encapsulating the core. The drug-loaded core structure sequentially includes an inner core layer and an intermediate core layer. The inner core layer is the chemotherapeutic drug cisplatin, and the intermediate core layer is PLGA with good biocompatibility. The outer surface of the PLGA is modified with a noble metal, wherein the noble metal is one or two of gold, ruthenium, and platinum. This invention also discloses a method for preparing the above-mentioned biomimetic targeted noble metal-based PLGA nanoparticle for lung cancer cell membranes. This nanoparticle and its preparation method can effectively target tumor cells and generate heat under near-infrared irradiation. The drug cisplatin loaded in the PLGA NPs will be exposed and released from the inside, achieving a synergistic effect of chemotherapy-photothermal therapy.

Description

Technical Field

[0001] This invention relates to the field of nanobiomedicine technology, specifically to a biomimetic targeting noble metal-based PLGA nanoparticle for lung cancer cell membranes, its preparation method, and its application. Background Technology

[0002] In the ongoing exploration and practice of cancer treatment, although traditional chemotherapy can inhibit tumor growth to a certain extent, the serious toxic side effects and drug resistance caused by its systemic distribution have always been problems that urgently need to be solved.

[0003] Nanoparticle drug delivery technology, by constructing nanoparticles with specific functions, enables targeted delivery and controlled release of drugs, thereby significantly improving efficacy and reducing side effects. However, single treatment methods often cannot fully meet the complex and ever-changing needs of tumor treatment. Photothermal therapy, as a non-invasive physical therapy method, utilizes the difference in temperature sensitivity and tolerance between tumor tissue and normal tissue. It uses laser irradiation to heat the tumor site to a certain temperature and maintain it for a period of time, achieving the goal of killing tumor cells without damaging normal tissue. Combining nanoparticle drug delivery technology with photothermal therapy not only enables precise targeted drug delivery but also further enhances the therapeutic effect through the photothermal effect, creating a synergistic effect.

[0004] However, existing nanoparticle-based photothermal therapy systems still have some shortcomings. For example, the long residence time of drug-carrying nanoparticles (NPs) in the body may lead to their accumulation and potential toxicity; the lack of specificity for tumor sites may cause thermal damage to normal tissues surrounding the tumor. Summary of the Invention

[0005] Based on the above description, the present invention provides a biomimetic targeting noble metal-based PLGA nanoparticle for lung cancer cell membranes, its preparation method, and its application.

[0006] In a first aspect, the present invention provides a biomimetic targeting noble metal-based PLGA nanoparticle for lung cancer cell membranes, wherein the nanoparticle comprises a drug-carrying core and a lung cancer cell membrane encapsulating the core.

[0007] Preferably, the drug-loaded core structure comprises an inner core layer and an intermediate core layer in sequence; the inner core layer is the chemotherapy drug cisplatin, the intermediate core layer is PLGA with good biocompatibility, and the outer surface of the PLGA is modified with a noble metal, wherein the noble metal is one or two of gold, ruthenium, and platinum.

[0008] Secondly, the present invention provides a method for preparing biomimetic targeting noble metal-based PLGA nanoparticles for lung cancer cell membranes, the preparation method comprising:

[0009] (i) Preparation of Cis-loaded PLGA NPs (Cis@PLGA NPs) using emulsion solvent evaporation method.

[0010] (ii) Surface modification of precious metals (PM) with HS-PEG-NH2 (PM-PEG).

[0011] (III) Cis@PLGA NPs and PM-PEG were coupled by amide reaction to prepare Cis@PLGA-PEG-PM NPs.

[0012] (iv) Noble metal-modified Cis@PLGA NPs drug-carrying nanoparticles coated on lung cancer cell membranes (LCM@Cis@PLGA-PEG-PM NPs).

[0013] Furthermore, the preparation method of Cis-loaded PLGA NPs (Cis@PLGA NPs) using the emulsion solvent evaporation method described in step (I) specifically includes: dissolving the drug cisplatin (Cis) and PLGA in 10 mL of chloroform at a mass ratio of 50:50 to form a homogeneous organic phase solution; then adding 20 mL of 2% polyvinyl alcohol as an aqueous phase solution as a stabilizer; after the organic and aqueous phases are mutually saturated, emulsifying the mixture with 250 W ultrasound for 10 minutes, evaporating the organic solvent, centrifuging at 20,000 rpm for 30 minutes, and finally purifying the Cis-loaded PLGA NPs (Cis@PLGA NPs).

[0014] Furthermore, the PLGA mentioned in step (i) is a carboxyl-functionalized PLGA with a molecular weight of 80,000.

[0015] Furthermore, the noble metal surface modification HS-PEG-NH2 (PM-PEG) method described in step (II) specifically includes: preparing a 100mM noble metal salt solution and a 100mM HS-PEG-NH2 solution, adjusting the pH of the reaction solution to a weakly alkaline condition; then, under stirring, slowly adding the reducing agent sodium borohydride (NaBH4, 10mM) to the noble metal salt solution, centrifuging at 16000g for 10min at 4℃, and washing twice to obtain PM-PEG.

[0016] Furthermore, the noble metal salt ion mentioned in step (ii) is Au. 3+ Ru 3+ Pt 4+ One or two of the above; the molar ratio of the noble metal salt, HS-PEG-NH2 and NaBH4 is 1:(3-4):(3-4).

[0017] Furthermore, the amide reaction coupling method described in step (iii) specifically includes: dispersing Cis@PLGA NPs in a 30% ethanol solution, adding an EDC-NHS acylation catalyst (5 mM, EDC and NHS mixed in a molar ratio of 1:1.2), and stirring for 30 minutes to activate the carboxyl groups on the surface of Cis@PLGA NPs. Subsequently, adding PM-PEG prepared in step (ii) in a molar ratio of 1:1 and stirring for 20 minutes allows the activated carboxyl groups on the surface of PLGA NPs to undergo an amidation reaction with the amino groups on PM-PEG, forming amide bonds to obtain Cis@PLGA-PEG-PM NPs.

[0018] Furthermore, the method for coating lung cancer cell membranes with noble metal-modified Cis@PLGA NPs nanoparticles in step (iv) specifically includes: taking A549 lung cancer cells in the logarithmic growth phase, scraping the cells off with a cell scraper, collecting the cells by centrifugation at 500g, washing with isotonic pre-cooled PBS, discarding the supernatant after centrifugation, adding hypotonic solution and incubating on ice for 20 minutes, repeatedly freezing and thawing the cell solution after the ice bath in room temperature and liquid nitrogen until the cells are completely broken, then centrifuging at 500g to obtain the supernatant, and centrifuging at 15000g to obtain the precipitate, which is the cell membrane fragment, and then sonicating it in an ice bath with an ultrasonic cell disruptor to obtain uniformly dispersed nanoscale cell membrane fragments. Then, the noble metal-modified Cis@PLGA NPs drug-carrying nanoparticles were vortex-mixed with lung cancer cell membrane fragments at a mass ratio of 1:3, and allowed to stand for 30 minutes. Subsequently, the mixture was filtered 3 to 5 times through 0.75μm, 0.45μm and 0.22μm filter membranes, respectively, according to the pore size from large to small, to obtain lung cancer cell membrane biomimetic targeting noble metal-based PLGA drug-carrying nanoparticles.

[0019] Thirdly, the present invention provides an application of biomimetic targeting noble metal-based PLGA nanoparticles for lung cancer cell membrane in the treatment of lung cancer, as described in the first aspect.

[0020] The mechanism of action of the drug-loaded nanoparticles of this invention is as follows: cisplatin is encapsulated in biocompatible and biodegradable PLGA to form nanoparticles (NPs), and noble metal atoms are modified onto these NPs. Since these NPs resonate in the near-infrared direction, and PLGA is biodegradable, heat is generated during near-infrared irradiation, accelerating the hydrolysis of the PLGA NPs. This exposes and releases the cisplatin loaded within the PLGA NPs, resulting in a significant synergistic effect of chemophotothermal therapy.

[0021] The beneficial effects of this invention are:

[0022] First, by disguising nanoparticles with cancer cell membranes, they can actively sense and target tumor cells, mitigating the clearance effect of the immune system. Second, by encapsulating the drug within biocompatible PLGA, premature drug release in the bloodstream is reduced, lowering non-specific toxicity to normal tissues. Furthermore, the superior photothermal conversion properties of noble metal materials (gold, ruthenium, platinum) efficiently convert light energy into heat energy; localized heating not only promotes the degradation of the PLGA matrix but also accelerates the release of cisplatin. This combination of chemotherapy (cisplatin's cytotoxic effects) and photothermal therapy (NIR-induced local high-temperature killing of cancer cells) demonstrates a significant synergistic effect. Attached Figure Description

[0023] Figure 1 a is a TEM morphology image of the LCM@Cis@PLGA-PEG-Au / Ru NPs drug-carrying nanoparticles prepared in Example 4 of this invention; Figure 1 b is a TEM image of the LCM@Cis@PLGA-PEG-Au / Pt NPs drug-carrying nanoparticles prepared in Example 5 of this invention; Figure 1 c is a TEM image of the LCM@Cis@PLGA-PEG-Ru / Pt NPs nanoparticles prepared in Example 6 of this invention, with a scale bar of 100 nm.

[0024] Figure 2 The results show the biocompatibility of noble metal-based PLGA nanoparticles with and without lung cancer cell membranes.

[0025] Figure 3 Results of targeting analysis of noble metal-based PLGA nanoparticles for biomimetic targeting of lung cancer cell membranes.

[0026] Figure 4 To simulate the thermal cracking of PLGA on the surface of drug-loaded nanoparticles under near-infrared irradiation conditions, releasing the internal drug.

[0027] Figure 5 To enhance the tumor-killing ability of noble metal-based PLGA nanoparticles that are biomimetic targeting of lung cancer cell membranes.

[0028] Figure 6 The curves show the changes in tumor volume in tumor-bearing mice after receiving different treatments.

[0029] Figure 7H&E staining images of tumors in tumor-bearing mice after different treatments, where a: PBS; b: Cis; c: Cis@PLGA-PEG-Au NPs; d: Cis@PLGA-PEG-Au NPs+NIR; e: LCM@Cis@PLGA-PEG-Au NPs+NIR; f: LCM@Cis@PLGA-PEG-Au / Ru NPs+NIR. Detailed Implementation

[0030] The present invention will be further described below with reference to embodiments.

[0031] Example 1: A method for preparing biomimetic targeted noble metal (gold) PLGA nanoparticles for lung cancer cell membranes, comprising the following steps:

[0032] (1) The drug cisplatin (Cis) and carboxyl-functionalized PLGA were dissolved in 10 mL of chloroform at a mass ratio of 50:50 to form a homogeneous organic phase solution. Then, 20 mL of 2% polyvinyl alcohol was added to the organic solution as an aqueous phase solution as a stabilizer. After the organic and aqueous phases were saturated, the mixture was emulsified with 250 W ultrasound for 10 minutes, the organic solvent was evaporated, and the mixture was centrifuged at 20,000 rpm for 30 minutes to finally purify the Cis-loaded PLGA NPs (Cis@PLGA NPs).

[0033] (2) Prepare 100 mM HAuCl4 solution and 100 mM HS-PEG-NH2 solution, adjust the pH of the reaction solution to 7.4, and slowly add sodium borohydride (NaBH4, 10 mM) as a reducing agent to the HAuCl4 solution while stirring. The molar ratio of HAuCl4, HS-PEG-NH2 and NaBH4 is 1:3:3. Centrifuge at 16000 g for 10 min at 4 °C and wash twice to obtain PM-PEG.

[0034] (3) EDC and NHS were mixed in a molar ratio of 1:1.2 to prepare a 5mM EDC-NHS acylation catalyst. Then, Cis@PLGA NPs were dispersed in a 30% ethanol solution, and the EDC-NHS acylation catalyst was added. The mixture was stirred for 30 minutes to activate the carboxyl groups on the surface of Cis@PLGA NPs. Subsequently, PM-PEG prepared in step (2) was added in a molar ratio of 1:1 and stirred for 20 minutes to allow the activated carboxyl groups on the surface of PLGA NPs to undergo an amidation reaction with the amino groups on PM-PEG to form amide bonds, thus obtaining Cis@PLGA-PEG-PM NPs.

[0035] (4) A549 lung cancer cells in the logarithmic growth phase were collected by scraping off the cells with a cell scraper, centrifuged at 500g, washed with isotonic pre-cooled PBS, centrifuged again, the supernatant was discarded, and a hypotonic solution was added and the cells were incubated on ice for 20 minutes. The cell solution after the ice bath was repeatedly frozen and thawed at room temperature and in liquid nitrogen until the cells were completely broken. Then, the supernatant was obtained by centrifugation at 500g, and the precipitate obtained by centrifugation at 15000g was cell membrane fragments. These fragments were then ultrasonically treated in an ice bath using an ultrasonic cell disruptor to obtain uniformly dispersed nanoscale cell membrane fragments. Then, Cis@PLGA-PEG@Au NPs drug-carrying nanoparticles and lung cancer cell membrane fragments were vortexed and mixed evenly at a mass ratio of 1:3. After standing for 30 minutes, the mixture was filtered 3-5 times through 0.75μm, 0.45μm and 0.22μm filter membranes, respectively, according to the pore size from large to small, to obtain lung cancer cell membrane biomimetic targeted noble metal (gold) PLGA drug-carrying nanoparticles LCM@Cis@PLGA-PEG-Au NPs.

[0036] Example 2: A method for preparing biomimetic targeted noble metal (ruthenium) PLGA nanoparticles for lung cancer cell membranes, comprising the following steps:

[0037] The difference between this embodiment and Example 1 is that the noble metal modified on the Cis@PLGA surface is Ru, the noble metal salt solution used is RuCl3, and the molar ratio of RuCl3, HS-PEG-NH2, and NaBH4 is 1:3:3. Other steps are the same as in Example 1, ultimately yielding LCM@Cis@PLGA-PEG-Ru NPs.

[0038] Example 3: A method for preparing biomimetic targeted noble metal (platinum) PLGA nanoparticles for lung cancer cell membranes, comprising the following steps:

[0039] The difference between this embodiment and Embodiment 1 is that the noble metal modified on the Cis@PLGA surface is Pt, and the noble metal salt solution used is H2PtCl6. 4+ The reaction molar ratio of HS-PEG-NH2 and NaBH4 was 1:4:4, and the other steps were the same as in Example 1, finally yielding LCM@Cis@PLGA-PEG-Pt NPs.

[0040] Example 4: A method for preparing biomimetic targeted noble metal (gold, ruthenium) PLGA nanoparticles for lung cancer cell membranes, comprising the following steps:

[0041] The difference between this embodiment and Embodiment 1 is that the noble metals modified on the Cis@PLGA surface are Au and Ru, and the noble metal salt solution used is a mixture of HAuCl4 and RuCl3. 3+ Ru 3+The reaction molar ratio of HS-PEG-NH2 and NaBH4 was 0.5:0.5:3:3, and the other steps were the same as in Example 1, finally yielding LCM@Cis@PLGA-PEG-Au / Ru NPs.

[0042] Example 5: A method for preparing biomimetic targeted noble metal (gold, platinum) PLGA nanoparticles for lung cancer cell membranes, comprising the following steps:

[0043] The difference between this embodiment and Embodiment 1 is that the noble metals modified on the Cis@PLGA surface are Au and Pt, and the noble metal salt solution used is a mixture of HAuCl4 and H2PtCl6. 3+ Pt 4+ The reaction molar ratio of HS-PEG-NH2 and NaBH4 was 0.5:0.5:4:4, and the other steps were the same as in Example 1, finally yielding LCM@Cis@PLGA-PEG-Au / Pt NPs.

[0044] Example 6: A method for preparing biomimetic targeted noble metal (ruthenium, platinum) PLGA nanoparticles for lung cancer cell membranes, comprising the following steps:

[0045] The difference between this embodiment and Embodiment 1 is that the noble metals modified on the Cis@PLGA surface are Ru and Pt, and the noble metal salt solution used is a mixture of RuCl3 and H2PtCl6. 3+ Pt 4+ The reaction molar ratio of HS-PEG-NH2 and NaBH4 was 0.5:0.5:4:4, and the other steps were the same as in Example 1, finally yielding LCM@Cis@PLGA-PEG-Au / Pt NPs.

[0046] Example 7: Morphological characterization of the drug-loaded nanoparticles prepared in Examples 4-6 of this invention.

[0047] Dissolve an appropriate amount of the prepared sample in deionized water, and after superdispersion, drop 5 μL onto a carbon-coated copper grid. Allow it to adsorb naturally and air dry at room temperature. Observe the morphology of the nanoparticles under a transmission electron microscope at 200 kV.

[0048] TEM characterization images of the LCM@Cis@PLGA-PEG-Au / Ru NPs, LCM@Cis@PLGA-PEG-Au / Pt NPs, and LCM@Cis@PLGA-PEG-Ru / Pt NPs drug-loaded nanoparticles prepared in Examples 4, 5, and 6 of this invention are shown below. Figure 1 As shown in Figure ac, the nanoparticles have a regular spherical structure, uniform size, and obvious membrane coating characteristics, indicating that the nanoparticles coated with lung cancer cell membranes have been successfully synthesized.

[0049] Example 8: Comparison of biocompatibility of lung cancer cell membrane-coated noble metal-based PLGA drug-carrying nanoparticles

[0050] To further verify the biocompatibility of the materials of this invention, Cis@PLGA-PEG-Au NPs, Cis@PLGA-PEG-Ru NPs, Cis@PLGA-PEG-Pt NPs, LCM@Cis@PLGA-PEG-Au NPs, LCM@Cis@PLGA-PEG-Au NPs, LCM@Cis@PLGA-PEG-Ru NPs, and LCM@Cis@PLGA-PEG-Pt NPs were prepared according to the method for preparing biomimetic targeted noble metal-based PLGA nanoparticles for lung cancer cell membranes of this invention. Normal human lung epithelial cells BEAS-2B were used as a cell model. BEAS-2B cells (8×10⁻⁶) were... 3 Cells were seeded into 96-well plates with 100 μL of culture medium added to each well. After 24 hours of cell culture, the original culture medium was removed, and culture medium containing the above six types of nanoparticles was added. The plates were then incubated at 37°C in a 5% CO2 incubator for another 24 hours. 10 μL of CCK-8 solution was added to each well of the plate, and after incubation for 1-3 hours, the absorbance at 450 nm was measured using a microplate reader to calculate cell viability.

[0051] like Figure 2 As shown, the average cell viability of cell-membrane-uncoated single noble metal-based PLGA nanoparticles (Cis@PLGA-PEG-AuNPs, Cis@PLGA-PEG-Ru NPs, Cis@PLGA-PEG-Pt NPs) was approximately 80%, indicating that the cell-membrane-uncoated single noble metal-based PLGA nanoparticles have a certain degree of biocompatibility. After treatment with cancer cell-coated single noble metal-based PLGA nanoparticles (LCM@Cis@PLGA-PEG-Au NPs, LCM@Cis@PLGA-PEG-Ru NPs, LCM@Cis@PLGA-PEG-Pt NPs), the viability of BEAS-2B cells increased to over 90%, further improving the biocompatibility of the nanoparticles.

[0052] Example 9: Targeting Analysis of Biomimetic Targeting Noble Metal-Based PLGA Nanoparticles for Lung Cancer Cell Membrane

[0053] Under laser irradiation conditions, the specificity of biomimetic targeted noble metal-based PLGA nanoparticles for lung cancer cell membranes was evaluated by flow cytometry. Pancreatic cancer cells (Panc02), breast cancer cells (MDA-MB-231), and lung cancer cells (A549) were seeded in 60 mm dishes and cultured for 24 h. Using the nanoparticles prepared in Example 1 as an example, culture medium containing LCM@Cis@PLGA-PEG-Au NPs nanoparticles was added, and the cells were cultured for another 24 h. Apoptosis and necrosis were then analyzed using the Annexin V-FITC apoptosis detection kit and flow cytometry.

[0054] The cytotoxicity of LCM@Cis@PLGA-PEG-Au NPs nanoparticles to homologous cells was further investigated by flow cytometry analysis of apoptosis / necrosis. To assess the percentage of viable cells (Q4), early apoptotic (Q3), late apoptotic (Q2), and necrotic (Q1) cells, in vitro cells after different treatments were stained with Annexin V / PI. Figure 3 The results showed that, compared with the PBS control group, the percentages of apoptosis and necrosis in pancreatic cancer cells Panc02 and breast cancer cells MDA-MB-231 treated with laser irradiation and LCM@Cis@PLGA-PEG-Au NPs nanoparticles were lower, indicating that LCM@Cis@PLGA-PEG-Au NPs nanoparticles had no tumor-killing ability against heterologous cells and could not specifically recognize and kill them. A549 cells treated with laser irradiation of LCM@Cis@PLGA-PEG-Au NPs nanoparticles showed significant apoptosis and necrosis, approximately 92%, confirming the high specificity of LCM@Cis@PLGA-PEG-Au NPs nanoparticles in killing homologous cells.

[0055] Example 10: Under simulated near-infrared irradiation conditions, the PLGA surface of the drug-loaded nanoparticles ruptures upon heating, releasing the internal drug.

[0056] A549 cells were distributed at a rate of 1 × 10⁶ cells per well. 5Cells were seeded at a density of [insert cell density here] / mL in 6-well cell culture plates and cultured at 37°C in a 5% CO2 incubator for 24 h. The original culture medium was removed, and the cells were treated with culture medium containing LCM@Cis@PLGA-PEG-Au NPs nanoparticles and LCM@Cis@PLGA-PEG-Au / Ru NPs nanoparticles, respectively. The cells were then cultured at 37°C in a 5% CO2 incubator for another 24 h. Simultaneously, normal A549 cells were cultured as a negative control. After 24 hours, the two groups containing LCM@Cis@PLGA-PEG-Au NPs and LCM@Cis@PLGA-PEG-Au / Ru NPs nanoparticles were irradiated with an 808 nm laser for 10 minutes, while the other two groups were not treated with laser irradiation. 10 μL of CCK-8 solution was added to each well of the plate, and after incubation for 1–3 hours, the absorbance at 450 nm was measured using a microplate reader to calculate cell viability.

[0057] like Figure 4 As shown, under simulated in vivo near-infrared irradiation conditions, the noble metals in the LCM@Cis@PLGA-PEG-Au NPs+NIR and LCM@Cis@PLGA-PEG-Au / Ru NPs+NIR groups firstly, as photothermal converters, efficiently convert the absorbed NIR light energy into heat energy, leading to a local temperature increase around the nanoparticles. This triggers the thermally responsive degradation of the PLGA polymer, accelerating the release of the encapsulated anticancer drug cisplatin (Cis). The cell viability of the LCM@Cis@PLGA-PEG-Au NPs+NIR group was approximately 33%, and that of the LCM@Cis@PLGA-PEG-Au / Ru NPs+NIR group was approximately 22%. This not only demonstrates the photothermal synergistic effect of the drug on lung cancer cells but also highlights the performance advantages of the dual noble metal materials. In the group without NIR irradiation treatment, due to the lack of photothermal conversion effect, PLGA did not undergo thermally responsive degradation, and the natural degradation rate remained relatively slow, resulting in only a weak release of the encapsulated drug Cis. The drug-loaded nanoparticles did not exhibit any additional effects on cell viability, indicating that their photothermal effect was inactive under these conditions and did not directly participate in or affect cell viability. The cell viability of both groups remained at a high level, with the viability of LCM@Cis@PLGA-PEG-Au NPs group being approximately 73% and the viability of LCM@Cis@PLGA-PEG-Au / Ru NPs group being approximately 66%.

[0058] Example 11: Tumor-killing ability of biomimetic targeted noble metal-based PLGA nanoparticles for lung cancer cell membrane

[0059] According to the method for preparing biomimetic targeted noble metal-based PLGA nanoparticles for lung cancer cell membranes of the present invention, LCM@Cis@PLGA-PEG-Au NPs nanoparticles, LCM@Cis@PLGA-PEG-Ru NPs nanoparticles, LCM@Cis@PLGA-PEG-Pt NPs nanoparticles, LCM@Cis@PLGA-PEG-Au / Ru NPs nanoparticles, LCM@Cis@PLGA-PEG-Au / Pt NPs nanoparticles, and LCM@Cis@PLGA-PEG-Ru / Pt NPs nanoparticles and Cis@PLGA-PEG-Ru NPs nanoparticles were prepared. A549 cells (8×10⁻⁶) were then subjected to these preparations. 3 The cells were seeded into 96-well plates with 100 μL of culture medium added to each well. After 24 h of cell culture, the original culture medium was removed, and culture medium containing the above six types of nanoparticles was added. The plates were then incubated at 37°C in a 5% CO2 incubator for another 24 h. The cells were then irradiated with an 808 nm laser for 10 minutes, and 10 μL of CCK-8 solution was added to each well. After incubation for 1-3 hours, the absorbance at 450 nm was measured using a microplate reader to calculate cell viability.

[0060] The cell proliferation assay was used to study the cancer cell killing efficiency of biomimetic targeted noble metal-based PLGA nanoparticles for lung cancer cells, such as... Figure 5As shown, the average viability of A549 cells treated with single noble metal-based PLGA nanoparticles (LCM@Cis@PLGA-PEG-Au NPs, LCM@Cis@PLGA-PEG-Ru NPs, LCM@Cis@PLGA-PEG-Pt NPs) coated with cancer cells and followed by near-infrared irradiation was approximately 33%, indicating that the single noble metal-based PLGA nanoparticles coated with cancer cells can specifically recognize target cells and effectively kill tumor cells. Notably, cell viability further decreased after treatment with cancer cell-coated bimetallic PLGA nanoparticles (LCM@Cis@PLGA-PEG-Au / Ru NPs, LCM@Cis@PLGA-PEG-Au / Pt NPs, and LCM@Cis@PLGA-PEG-Ru / Pt NPs) combined with near-infrared irradiation. Among these, the LCM@Cis@PLGA-PEG-Au / Ru NPs nanoparticle treatment group showed a more significant tumor-killing effect when combined with near-infrared irradiation. This may be related to the synergistic enhancement of the photothermal effect between the bimetallic nanostructures. Under NIR light irradiation, the bimetals induce a stronger localized surface plasmon resonance (LSPR) effect, which promotes the efficient conversion of light energy to heat energy. Compared to single noble metal-based nanoparticles, bimetallic nanostructures provide more hotspot areas, resulting in more concentrated heat and a higher temperature gradient within the target cells, effectively enhancing the local thermotherapy effect.

[0061] Example 12: Tumor growth inhibition effect of lung cancer cell membrane biomimetic targeted noble metal-based PLGA nanoparticles coupled with near-infrared irradiation

[0062] A549 cells (3 × 10) 6 100 μL of Ham's F-12K medium was used to subcutaneously inoculate male Balb / c nude mice (8-10 weeks old, 20 g). Tumor volume was measured using digital calipers and calculated using the following formula: Tumor volume = (Tumor length) × (Tumor width) 2 / 2. When the tumor volume reaches 50mm 3 Mice were treated with Cis, Cis@PLGA-PEG@Au NPs, Cis@PLGA-PEG@Au NPs+NIR, LCM@Cis@PLGA-PEG@Au NPs+NIR, and LCM@Cis@PLGA-PEG@Au / Ru NPs+NIR (40 μL, Cis concentration equivalent to 5 μg / mL). All formulations were injected into mice via the tail vein every 2 days. Near-infrared irradiation was administered (or not) according to group assignment. Three hours after injection, mice were irradiated with an 808 nm laser (2.83 W / cm²). 2Ten minutes after treatment, control mice were injected with PBS. Tumor volume (V) was measured every two days for 16 days. Tumor volume changes during treatment were expressed as relative tumor volume V / V0 (V0 being the tumor volume at the start of treatment). After 16 days, mice were sacrificed, and tumors were fixed in 10% neutral buffered formalin for 24 hours, washed with PBS, and stored in 70% ethanol (4°C). After OCT embedding, tumors were cut into ~5 μm pieces, stained with hematoxylin and eosin (H&E), and analyzed using an optical microscope.

[0063] To maximize treatment efficacy, patients were divided into five groups: Cis, Cis@PLGA-PEG-Au NPs, Cis@PLGA-PEG-Au NPs+NIR, LCM@Cis@PLGA-PEG-Au NPs+NIR, and LCM@Cis@PLGA-PEG-Au / Ru NPs+NIR. A control group receiving no treatment was also included. Figure 6 As shown, at the end of the experiment, untreated tumors grew to 5.3 times their initial size, while free Cis treatment initially only slightly reduced tumor size compared to the original size. Comparing the tumor growth rates of the Cis@PLGA-PEG-Au NPs and Cis@PLGA-PEG-Au NPs+NIR treatment groups, it was found that near-infrared irradiation indeed enhanced the efficacy of the nanoparticles; this indicates that the precious metal gold on the nanoparticles exerted a photothermal effect, resulting in a better therapeutic effect for lung cancer. Simultaneously, comparing the tumor growth rates of the Cis@PLGA-PEG-Au NPs+NIR and LCM@Cis@PLGA-PEG-Au NPs+NIR treatment groups, it was found that LCM@Cis@PLGA-PEG-Au NPs+NIR, coated with cancer cell membranes, had better therapeutic efficacy. This is due to the ingenious encapsulation of lung cancer cell membranes, which enabled the drug-carrying nanoparticles to target specific cancer cells, promoting drug accumulation and release at the tumor site. Similar to the results of in vivo experiments, the dual noble metal-based PLGA nanoparticles coated with cancer cells exhibited superior anti-tumor effects under NIR irradiation compared to single noble metal-based PLGA nanoparticles, demonstrating a synergistic enhancement of the bimetallic photothermal effect.

[0064] Figure 7The images (af) show representative H&E-stained tumor sections after different treatments. Mice injected with PBS exhibited typical pathological features of lung cancer, such as tightly packed tumor cells. Tumor tissues from the Cis, Cis@PLGA-PEG-Au NPs, Cis@PLGA-PEG-Au NPs+NIR, LCM@Cis@PLGA-PEG-Au NPs+NIR, and LCM@Cis@PLGA-PEG-Au / Ru NPs+NIR groups all showed punctate necrosis and intercellular gaps. Furthermore, LCM@Cis@PLGA-PEG-Au / Ru NPs irradiated with 808nm laser showed the most significant tumor cell necrosis and shrinkage. Lung cancer cell membranes specifically target tumor tissue; under 808nm infrared irradiation, the heat generated by the outermost noble metal substrate and PLGA nanoshell, along with the released drugs, can jointly kill cancer cells, thereby enhancing the anti-cancer effect. Therefore, near-infrared photothermal therapy based on noble metals combined with cisplatin chemotherapy can achieve better anti-cancer efficacy than current single-therapies.

[0065] The present invention has been described above by way of example, and the description is relatively specific and detailed, but it should not be construed as limiting the scope of the present invention. Those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the present invention, and all such modifications and substitutions should be covered within the scope of the claims of the present invention.

Claims

1. A biomimetic targeting noble metal-based PLGA nanoparticle for lung cancer cell membranes, characterized in that: The formulation includes a drug-loaded core and a lung cancer cell membrane covering the core. The drug-loaded core structure comprises an inner nuclear layer and an intermediate nuclear layer. The inner nuclear layer is the chemotherapy drug cisplatin, and the intermediate nuclear layer is PLGA. The outer surface of the PLGA is modified with a noble metal, specifically two of gold, ruthenium, and platinum. The specific preparation method is as follows: S1: Cisplatin (Cis) and PLGA were dissolved in 10 mL of chloroform at a 1:1 mass ratio to form a homogeneous organic phase solution; then 20 mL of 2% polyvinyl alcohol was added as a stabilizer to the aqueous phase; after the organic and aqueous phases were saturated, the mixture was emulsified using 250 W ultrasound for 10 minutes; the organic solvent was evaporated, and the mixture was centrifuged at 20,000 rpm for 30 minutes to finally purify Cis@PLGA NPs loaded with Cis. S2: Prepare a 100mM noble metal salt solution and a 100mM HS-PEG-NH2 solution. Adjust the pH of the reaction solution to a weakly alkaline condition. Under stirring, slowly add 10mM sodium borohydride (NaBH4) to the noble metal salt solution. The noble metal ions, HS-PEG-NH2, and NaBH4 react in a certain proportion. Centrifuge at 16000g for 10 min at 4℃ and wash twice to obtain PM-PEG. S3: Amidotropic coupling of Cis@PLGA NPs and PM-PEG to prepare noble metal-modified Cis@PLGA NPs nanoparticles Cis@PLGA-PEG-PM NPs. The specific steps are as follows: EDC and NHS are mixed in a molar ratio of 1:1.2 to prepare a 5mM EDC-NHS acylation catalyst. Then, Cis@PLGA NPs are dispersed in a 30% ethanol solution, and the EDC-NHS acylation catalyst is added. The mixture is stirred for 30 minutes to activate the carboxyl groups on the surface of Cis@PLGA NPs. Subsequently, PM-PEG prepared in step S2 is added in a certain proportion and stirred for 20 minutes to allow the activated carboxyl groups on the surface of PLGA NPs to undergo an amidation reaction with the amino groups on PM-PEG to form amide bonds, thus obtaining Cis@PLGA-PEG-PM NPs. S4: Lung cancer cell membrane coated with noble metal-modified Cis@PLGANPs nanoparticles, specifically including: taking A549 lung cancer cells in the logarithmic growth phase, scraping the cells off with a cell scraper, collecting the cells by centrifugation at 500g, washing with isotonic pre-cooled PBS, discarding the supernatant after centrifugation, adding hypotonic solution and incubating on ice for 20 minutes, repeatedly freezing and thawing the cell solution at room temperature and in liquid nitrogen until the cells are completely broken, then centrifuging at 500g to obtain the supernatant, centrifuging at 15000g to obtain the precipitate, which is the cell membrane fragment, and then sonicating on ice in an ultrasonic cell disruptor to obtain uniformly dispersed nanoscale cell membrane fragments, then vortexing the noble metal-modified Cis@PLGA NPs nanoparticles and lung cancer cell membrane fragments at a mass ratio of 1:3, letting stand for 30 minutes, and then filtering through 0.75μm, 0.45μm and 0.22μm filter membranes 3-5 times respectively according to the pore size from large to small, to obtain lung cancer cell membrane biomimetic targeted noble metal-based PLGA nanoparticles.

2. The method for preparing drug-loaded nanoparticles according to claim 1, characterized in that, The PLGA mentioned in step S1 is a carboxyl-functionalized PLGA with a molecular weight of 80,000.

3. The method for preparing drug-loaded nanoparticles according to claim 1, characterized in that, The pH of the reaction solution in step S2 is 7.

4.

4. The method for preparing drug-loaded nanoparticles according to claim 1, characterized in that, The noble metal ion mentioned in step S2 is Au. 3+ Ru 3+ Pt 4+ The two types of the noble metal salt, HS-PEG-NH2 and NaBH4 react in a molar ratio of 1:(3-4):(3-4).

5. The method for preparing drug-loaded nanoparticles according to claim 1, characterized in that, The molar ratio of Cis@PLGANPs to PM-PEG is 1:

1.

6. The use of lung cancer cell membrane biomimetic targeting noble metal-based PLGA nanoparticles as described in any one of claims 1 to 5 in the preparation of lung cancer therapeutic drugs.

Images