Hollow‐Core Magnetic Colloidal Nanocrystal Clusters with Ligand‐Exchanged Surface Modification as Delivery Vehicles for Targeted and Stimuli‐Responsive Drug Release

The fabrication of hierarchical magnetic nanomaterials with well‐defined structure, high magnetic response, excellent colloidal stability, and biocompatibility is highly sought after for drug‐delivery systems. Herein, a new kind of hollow‐core magnetic colloidal nanocrystal cluster (HMCNC) with porous shell and tunable hollow chamber is synthesized by a one‐pot solvothermal process. Its novelty lies in the “tunability” of the hollow chamber and of the pore structure within the shell through controlled feeding of sodium citrate and water, respectively. Furthermore, by using the ligand‐exchange method, folate‐modified poly(acrylic acid) was immobilized on the surface of HMCNCs to create folate‐targeted HMCNCs (folate‐HMCNCs), which endowed them with excellent colloidal stability, pH sensitivity, and, more importantly, folate receptor‐targeting ability. These assemblages exhibited excellent colloidal stability in plasma solution. Doxorubicin (DOX), as a model anticancer agent, was loaded within the hollow core of these folate‐HMCNCs (folate‐HMCNCs‐DOX), and drug‐release experiments proved that the folate‐HMCNCs‐DOX demonstrated pH‐dependent release behavior. The folate‐HMCNCs‐DOX assemblages also exhibited higher potent cytotoxicity to HeLa cells than free doxorubicin. Moreover, folate‐HMCNCs‐DOX showed rapid cell uptake apart from the enhanced cytotoxicity to HeLa cells. Experimental results confirmed that the synthesized folate‐HMCNCs are smart nanovehicles as a result of their improved folate receptor‐targeting abilities and also because of their combined pH‐ and magnetic‐stimuli response for applications in drug delivery.     

Dual‐Targeted Selenium Nanoparticles for Synergistic Photothermal Therapy and Chemotherapy of Tumors

A combination of chemo‐ and photothermal therapy has emerged as a promising tactic for cancer therapy. However, the intricacy of accurate delivery and the ability to initiate drug release in specific tumor sites remains a challenging puzzle. Hence, to assure that the chemotherapeutic drug and photothermal agent are synchronously delivered to a tumor area for their synergistic effect, dual‐target (RC‐12 and PG‐6 peptides) functionalized selenium nanoparticles loaded with both doxorubicin (DOX) and indocyanine green (ICG) were designed and successfully synthesized. The as‐synthesized nanoparticles exhibited good monodispersity, size stability, and consistent spectral characteristics compared with those of ICG or DOX alone. The nanoparticles underwent self‐immolated cleavage under irradiation from a near‐IR laser and released the loaded drug owing to sufficient hyperthermia. Moreover, the internalized nanoparticles triggered the overproduction of intracellular reactive oxygen species to induce cell apoptosis. Taken together, this study provides a sequentially triggered nanosystem to achieve precise drug delivery by chemo‐photothermal combination.     

Facile Solvothermal Synthesis of Mesostructured Fe3O4/Chitosan Nanoparticles as Delivery Vehicles for pH‐Responsive Drug Delivery and Magnetic Resonance Imaging Contrast Agents

We report a facile fabrication of a host–metal–guest coordination‐bonding system in a mesostructured Fe₃O₄/chitosan nanoparticle that can act as a pH‐responsive drug‐delivery system. The mesostructured Fe₃O₄/chitosan was synthesized by a solvothermal approach with iron(III) chloride hexahydrate as a precursor, ethylene glycol as a reducing agent, ammonium acetate as a porogen, and chitosan as a surface‐modification agent. Subsequently, doxorubicin (DOX), acting as a model drug (guest), was loaded onto the mesostructured Fe₃O₄/chitosan nanoparticles, with chitosan acting as a host molecule to form the NH₂? Zn^II? DOX coordination architecture. The release of DOX can be achieved through the cleavage of coordination bonds that are sensitive to variations in external pH under weakly acidic conditions. The pH‐responsive nature of the nanoparticles was confirmed by in vitro releases and cell assay tests. Furthermore, the relaxation efficiency of the nanoparticles as high‐performance magnetic resonance imaging contrast agents was also investigated. Experimental results confirm that the synthesized mesostructured Fe₃O₄/chitosan is a smart nanovehicle for drug delivery owing to both its pH‐responsive nature and relaxation efficiency.     

Tumour‐Targeted Drug Delivery with Mannose‐Functionalized Nanoparticles Self‐Assembled from Amphiphilic β‐Cyclodextrins

Multivalent mannose‐functionalized nanoparticles self‐assembled from amphiphilic β‐cyclodextrins (β‐CDs) facilitate the targeted delivery of anticancer drugs to specific cancer cells. Doxorubicin (DOX)‐loaded nanoparticles equipped with multivalent mannose target units were efficiently taken up via receptor‐mediated endocytosis by MDA‐MB‐231 breast cancer cells that overexpress the mannose receptor. Upon entering the cell, the intracellular pH causes the release of DOX, which triggers apoptosis. Targeting by multivalent mannose significantly improved the capability of DOX‐loaded nanoparticles to inhibit the growth of MDA‐MB‐231 cancer cells with minimal side effects in vivo. This targeted and controlled drug delivery system holds promise as a nanotherapeutic for cancer treatment.     

An Adjustable pH‐Responsive Drug Delivery System Based on Self‐Assembly Polypeptide‐Modified Mesoporous Silica

In this study, an adjustable pH‐responsive drug delivery system using mesoporous silica nanoparticles (MSNs) as the host materials and the modified polypeptides as the nanovalves is reported. Since the polypeptide can self‐assemble via electrostatic interaction at pH 7.4 and be disassembled by pH changes, the modified poly(l ‐lysine) and poly(l ‐glutamate) are utilized for pore blocking and opening in the study. Poly(l ‐lysine)‐MSN (PLL‐MSN) and poly(l ‐glutamate)‐MSN (PLG‐MSN) are synthesized via the ring opening polymerization of N‐carboxyanhydrides onto the surface of mesoporous silica nanoparticles. The successful modification of the polypeptide on MSN is proved by Zeta potential change, X‐ray photoelectron spectroscopy (XPS), solid state NMR, and MALDI‐TOF MS. In vitro simulated dye release studies show that PLL‐MSN and PLG‐MSN can successfully load the dye molecules. The release study shows that the controlled release can be constructed at different pH by adjusting the ratio of PLL‐MSN to PLG‐MSN. Cellular uptake study indicates that the drug is detected in both cytoplasm and nucleus, especially in the nucleus. In vitro cytotoxicity assay indicates that DOX loaded mixture nanoparticles (ratio of PLL‐MSN to PLG‐MSN is 1:1) can be triggered for drug release in HeLa cells, resulting in 88% of cell killing.     

Preparation of a Camptothecin Prodrug with Glutathione‐Responsive Disulfide Linker for Anticancer Drug Delivery

We present here a novel camptothecin (CPT) prodrug based on polyethylene glycol monomethyl ether‐block‐poly(2‐methacryl ester hydroxyethyl disulfide‐graft‐CPT) (MPEG‐SS‐PCPT). It formed biocompatible nanoparticles (NPs) with diameters of approximately 122 nm with a CPT loading content as high as approximately 25 wt % in aqueous solution. In in vitro release studies, these MPEG‐SS‐PCPT NPs could undergo triggered disassembly and much faster release of CPT under glutathione (GSH) stimulus than in the absence of GSH. The CPT prodrug had high antitumor activity, and another anticancer drug, doxorubicin hydrochloride (DOX ? HCl), could also be introduced into the prodrug with a high loading amount. The DOX ? HCl‐loaded CPT prodrug could deliver two anticancer drugs at the same time to produce a collaborative cytotoxicity toward cancer cells, which suggested that this GSH‐responsive NP system might become a promising carrier to improve drug‐delivery efficacy.     

Synthesis,self‐assembly,drug‐release behavior,and cytotoxicity of triblock and pentablock copolymers composed of poly(ε‐caprolactone), poly(L‐lactide), and poly(ethylene glycol)

Biocompatible and biodegradable ABC and ABCBA triblock and pentablock copolymers composed of poly(ε‐caprolactone) (PCL), poly(L ‐lactide) (PLA), and poly(ethylene glycol) (PEO) with controlled molecular weights and low polydispersities were synthesized by a click conjugation between alkyne‐terminated PCL‐b‐PLA and azide‐terminated PEO. Their molecular structures, physicochemical and self‐assembly properties were thoroughly characterized by means of FT‐IR, ¹H‐NMR, gel permeation chromatography, differential scanning calorimetry, wide‐angle X‐ray diffraction, dynamic light scattering, and transmission electron microscopy. These copolymers formed microphase‐separated crystalline materials in solid state, where the crystallization of PCL block was greatly restricted by both PEO and PLA blocks. These copolymers self‐assembled into starlike and flowerlike micelles with a spherical morphology, and the micelles were stable over 27 days in aqueous solution at 37 °C. The doxorubicin (DOX) drug‐loaded nanoparticles showed a bigger size with a similar spherical morphology compared to blank nanoparticles, demonstrating a biphasic drug‐release profile in buffer solution and at 37 °C. Moreover, the DOX‐loaded nanoparticles fabricated from the pentablock copolymer sustained a longer drug‐release period (25 days) at pH 7.4 than those of the triblock copolymer. The blank nanoparticles showed good cell viability, whereas the DOX‐loaded nanoparticles killed fewer cells than free DOX, suggesting a controlled drug‐release effect. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2010     

以磁纳米粒为核的pH敏感型聚谷氨酸树状分子药物载体

报道了一种新的肽类树枝状分子改性磁性纳米药物载体.以天然氨基酸L-谷氨酸为原料,通过收敛法合成了聚(L-谷氨酸)树状分子,将多巴胺配体键合到聚(L-谷氨酸)树状分子上,用核磁(1H-NMR)、质谱(MS)对合成出的树状分子配体进行了表征,然后通过配体交换对四氧化三铁磁纳米粒表面进行多功能化.以阿霉素为模型药物通过pH敏...     

Stimuli‐responsive zein‐based nanoparticles as a potential carrier for ellipticine: Synthesis,release, and in vitro delivery

In the present research, we have investigated a drug delivery system based on the pH‐responsive behaviors of zein colloidal nanoparticles coated with sodium caseinate (SC) and poly ethylene imine (PEI). These systematically designed nanoparticles were used as nanocarriers for encapsulation of ellipticine (EPT), as an anticancer drug. SC and PEI coatings were applied through electrostatic adsorption, leading to the increased size and improved polydispersity index of nanoparticles as well as sustained release of drug. Physicochemical characteristics such as hydrodynamic diameter, size distribution, zeta potential and morphology of nanoparticles prepared using different formulations and conditions were also determined. Based on the results, EPT was encapsulated into the prepared nanoparticles with a high drug loading capacity (5.06%) and encapsulation efficiency (94.8%) under optimal conditions. in vitro experiments demonstrated that the release of EPT from zein‐based nanoparticles was pH sensitive. When the pH level decreased from 7.4 to 5.5, the rate of drug release was considerably enhanced. The mechanism of pH‐responsive complexation in the drug encapsulation and release processes was extensively investigated. The pH‐dependent electrostatic interactions and drug state were hypothesized to affect the release profiles. Compared to the EPT‐loaded zein/PEI nanoparticles, the EPT‐loaded zein/SC nanoparticles exhibited a better drug sustained‐release profile, with a smaller initial burst release and longer release period. According to the results of in vitro cytotoxicity experiments, drug‐free nanoparticles were associated with a negligible cytotoxicity, whereas the EPT‐loaded nanoparticles displayed a high toxicity for the cancer cell line, A549. Our findings indicate that these pH‐sensitive protein‐based nanoparticles can be used as novel nanotherapeutic tools and potential antineoplastic drug carriers for cancer chemotherapy with controlled release.     

Tragacanth gum‐based pH‐responsive magnetic hydrogels for “smart” chemo/hyperthermia therapy of solid tumors

The drug delivery performances of pH‐responsive magnetic hydrogels (MHs) composed of tragacanth gum (TG), poly(acrylic acid) (PAA), and Fe₃O₄ nanoparticles (NPs) were investigated in terms of physicochemical as well as biological features. The fabricated drug delivery systems (DDSs) were analyzed using Fourier transform infrared spectroscopy, X‐ray diffraction, vibrating sample magnetometer, scanning electron microscopy, and transmission electron microscopy. The synthesized MHs were loaded with doxorubicin hydrochloride (Dox) as a universal model anti‐cancer drug. The MHs showed excellent Dox loading and encapsulation efficiencies, mainly due to strong hydrogen bonding and electrostatic interaction between the drug and polymeric matrix, as well as porous micro‐structures of the fabricated MHs. The drug‐loaded MHs showed negligible drug release values in physiological condition. In contrast, in cancerous condition (pH 5.0), both MHs exhibited highest drug release values that qualified them as “smart” DDSs. The cytocompatibilities of the MHs as well as the cytotoxicity of the Dox‐loaded MHs were investigated against human epidermoid‐like carcinoma (Hela) cells through MTT assay. In addition, hyperthermia therapy induced by Fe₃O₄ NPs was applied to locally raise temperature inside the Hela cells at 45 ± 3°C to promote cell death. As a result, the Dox‐loaded MHs can be considered as potential DDSs for chemo/hyperthermia therapy of solid tumors.     

Hydrogen Peroxide and Glutathione Dual Redox‐Responsive Nanoparticles for Controlled DOX Release

Polymer nanoparticulate drug delivery systems that respond to reactive oxygen species (ROS) and glutathione (GSH) simultaneously at biologically relevant levels hold great promise to improve the therapeutic efficacy to cancer cells with reduced side effects of chemo drugs. Herein, a novel redox dual‐responsive amphiphilic block copolymer (ABP) that consists of a hydrophilic poly (ethylene oxide) block and a hydrophobic block bearing disulfide linked phenylboronic ester group as pendant is synthesized, and the DOX loaded nanoparticles (BSN‐DOX) based on ABPs with varied hydrophobic block length are fabricated for DOX delivery. The self‐immolative leaving reaction of phenylboronic ester triggered by extracellular ROS and the cleavage of disulfide linkages induced by intracellular GSH both lead to rapid DOX release from BSN‐DOX, resulting in an on‐demand DOX release. Moreover, BSN‐DOX show better tumor inhibition and lower side effects in vivo compared with free drug.     

肝靶向海藻酸钠载药纳米粒的细胞毒性研究

本研究将具有肝靶向性分子甘草次酸（GA）偶联在具有生物相容性和生物可降解性的天然高分子海藻酸钠（ALG）上,合成了甘草次酸改性的海藻酸钠（GA—ALG）;对广谱抗癌药物阿霉素（DOX）进行包封,制备了肝靶向载药纳米粒,并考察了GA—ALG载药纳米粒的体外释药性能和对肝癌细胞的抑制作用．利用核磁、红外和元素分析技术对GA—ALG结构和GA取代度进行了表征;对GA—ALG载药纳米粒的形貌、粒径、表面Zeta电位等进行了测定,结果显示纳米粒具有较规则球形结构,其水合粒径为（214±11）nm．GA—ALG载药纳米粒在模拟生理条件下（pH7．4）可持续释药长达20天;MTT结果显示GA-ALG载药纳米粒对7703肝癌细胞的具有明显的杀伤作用．     

Biocompatible Triplex Ag@SiO2@mTiO2 Core–Shell Nanoparticles for Simultaneous Fluorescence‐SERS Bimodal Imaging and Drug Delivery

Herein, we report the synthesis of biocompatible triplex Ag@SiO₂@mTiO₂ core–shell nanoparticles (NPs) for simultaneous fluorescence‐surface‐enhanced Raman scattering (F‐SERS) bimodal imaging and drug delivery. Stable Raman signals were created by typical SERS tags that were composed of Ag NPs for optical enhancement, a reporter molecule of 4‐mercaptopyridine (4‐Mpy) for a spectroscopic signature, and a silica shell for protection. A further coating of mesoporous titania (mTiO₂) on the SERS tags offered high loading capacity for a fluorescence dye (flavin mononucleotide) and an anti‐cancer drug (doxorubicin (DOX)), thereby endowing the material with fluorescence‐imaging and therapeutic functions. The as‐prepared F‐SERS dots exhibited strong fluorescence when excited by light at 460 nm whilst a stable, characteristic 4‐Mpy SERS signal was detected when the excitation wavelength was changed to longer wavelength (632.8 nm), both in solution and after incorporation inside living cells. Their excellent biocompatibility was demonstrated by low cytotoxicity against MCF‐7 cells, even at a high concentration of 100 μg mL^?1. In vitro cell cytotoxicity confirmed that DOX‐loaded F‐SERS dots had a comparable or even greater therapeutic effect compared with the free drug, owing to the increased cell‐uptake, which was attributed to the possible endocytosis mechanism of the NPs. To the best of our knowledge, this is the first proof‐of‐concept investigation on a multifunctional nanomedicine that possessed a combined capacity for fast and multiplexed F‐SERS labeling as well as drug‐loading for cancer therapy.     

NIR-triggered drug delivery system based on phospholipid coated ordered mesoporous carbon for synergistic chemo-photothermal therapy of cancer cells

Chemo-photothermal treatment is one of the most efficient strategies for cancer therapy. However, traditional drug carriers without near-infrared absorption capacity need to be loaded with materials behaving photothermal properties, as it results in complicated synthesis process, inefficient photothermal effects and hindered NIR-mediated drug release. Herein we report a facile synthesis of a polyethylene glycol (PEG) linked liposome (PEG-liposomes) coated doxorubicin (DOX)-loaded ordered mesoporous carbon (OMC) nanocomponents (PEG-LIP@OMC/DOX) by simply sonicating DOX and OMC in PEG-liposomes suspensions. The as-obtained PEG-LIP@OMC/DOX exhibits a nanoscale size (600±15 nm), a negative surface potential (-36.70 mV), high drug loading (131.590 mg/g OMC), and excellent photothermal properties. The PEG-LIP@OMC/DOX can deliver loaded DOX to human MCF-7 breast cancer cells (MCF-7) and the cell toxicity viability shows that DOX unloaded PEG-LIP@OMC has no cytotoxicity, confirming the PEG-LIP@OMC itself has excellent biocompatibility. The NIR-triggered release studies demonstrate that this NIR-responsive drug delivery system enables on-demand drug release. Furthermore, cell viability results using human MCF-7 cells demonstrated that the combination of NIR-based hyperthermal therapy and triggered chemotherapy can provide higher therapeutic efficacy than respective monotherapies. With these excellent features, we believe that this phospholipid coating based multifunctional delivery system strategy should promote the application of OMC in nanomedical applications.     

NIR-triggered drug delivery system based on phospholipid coated ordered mesoporous carbon for synergistic chemo-photothermal therapy of cancer cells

Chemo-photothermal treatment is one of the most efficient strategies for cancer therapy. However, traditional drug carriers without near-infrared absorption capacity need to be loaded with materials behaving photothermal properties, as it results in complicated synthesis process, inefficient photothermal effects and hindered NIR-mediated drug release. Herein we report a facile synthesis of a polyethylene glycol (PEG) linked liposome (PEG-liposomes) coated doxorubicin (DOX)-loaded ordered mesoporous carbon (OMC) nanocomponents (PEG-LIP@OMC/DOX) by simply sonicating DOX and OMC in PEG-liposomes suspensions. The as-obtained PEG-LIP@OMC/DOX exhibits a nanoscale size (600 ± 15 nm), a negative surface potential (−36.70 mV), high drug loading (131.590 mg/g OMC), and excellent photothermal properties. The PEG-LIP@OMC/DOX can deliver loaded DOX to human MCF-7 breast cancer cells (MCF-7) and the cell toxicity viability shows that DOX unloaded PEG-LIP@OMC has no cytotoxicity, confirming the PEG-LIP@OMC itself has excellent biocompatibility. The NIR-triggered release studies demonstrate that this NIR-responsive drug delivery system enables on-demand drug release. Furthermore, cell viability results using human MCF-7 cells demonstrated that the combination of NIR-based hyperthermal therapy and triggered chemotherapy can provide higher therapeutic efficacy than respective monotherapies. With these excellent features, we believe that this phospholipid coating based multifunctional delivery system strategy should promote the application of OMC in nanomedical applications.     

Mesoporous silica nanoparticles for 19F magnetic resonance imaging,fluorescence imaging,and drug delivery

Multifunctional mesoporous silica nanoparticles (MSNs) are good candidates for multimodal applications in drug delivery, bioimaging, and cell targeting. In particular, controlled release of drugs from MSN pores constitutes one of the superior features of MSNs. In this study, a novel drug delivery carrier based on MSNs, which encapsulated highly sensitive ¹⁹F magnetic resonance imaging (MRI) contrast agents inside MSNs, was developed. The nanoparticles were labeled with fluorescent dyes and functionalized with small molecule-based ligands for active targeting. This drug delivery system facilitated the monitoring of the biodistribution of the drug carrier by dual modal imaging (NIR/¹⁹F MRI). Furthermore, we demonstrated targeted drug delivery and cellular imaging by the conjugation of nanoparticles with folic acid. An anticancer drug (doxorubicin, DOX) was loaded in the pores of folate-functionalized MSNs for intracellular drug delivery. The release rates of DOX from the nanoparticles increased under acidic conditions, and were favorable for controlled drug release to cancer cells. Our results suggested that MSNs may serve as promising ¹⁹F MRI-traceable drug carriers for application in cancer therapy and bio-imaging.     

Co‐delivery of 10‐Hydroxycamptothecin with Doxorubicin Conjugated Prodrugs for Enhanced Anticancer Efficacy

Well‐defined amphiphilic linear‐dendritic prodrugs (MPEG‐b‐PAMAM‐DOX) are synthesized by conjugating doxorubicin (DOX), to MPEG‐b‐PAMAM through the acid‐labile hydrazone bond. The amphiphilic prodrugs form self‐assembled nanoparticles in deionized water and encapsulate the hydrophobic anticancer drug 10‐hydroxycamptothecin (HCPT) with a high drug loading efficiency. Studies on drug release and cellular uptake of the co‐delivery system reveal that both drugs are released in a pH‐dependent manner and effectively taken up by MCF‐7 cells. In vitro methyl thiazolyl tetrazolium (MTT) assays and drug‐induced apoptosis tests demonstrate the HCPT‐loaded nanoparticles suppress cancer cell growth more efficiently than the MPEG‐b‐PAMAM‐DOX prodrugs, free HCPT, and physical mixtures of MPEG‐b‐PAMAM‐DOX and HCPT at equivalent DOX or HCPT doses.

     

普鲁兰多糖的硬脂酸修饰及其作为纳米药物载体的研究

利用1-(3-二甲氨基丙基)-3-乙基碳二亚胺盐酸盐(EDC)和4-二甲氨基吡啶(DMAP)催化硬脂酸(SA)与具有良好生物相容性的普鲁兰多糖(Pullulan)反应, 将硬脂酸接枝在普鲁兰分子链的羟基上, 得到取代度不同的疏水改性两亲性普鲁兰多糖衍生物PUSA1, PUSA2 及PUSA3, 其临界胶束浓度分别为50, 32, 18 μg/mL; 透射电镜(TEM)图像显示透析法制备的PUSA 自组装颗粒为球形. 以阿霉素为模型药物制备了PUSA 载药纳米粒, 考察了载药纳米粒的载药量、包封率和体外药物释放. 结果表明PUSA3 的包封率高达84%, 载药量达7.79%. 药物可在37 ℃, pH＝7.4 的PBS 溶液中持续释放90 h 以上. 细胞毒性实验(MTT)结果显示当PUSA 的浓度高达1000 μg/mL 时48 h 后细胞存活率依然在90%左右. 流式细胞及荧光分析表明载药纳米粒的细胞摄取率远远高于游离药物. 说明PUSA 是一种新型的有潜在应用价值的药物载体材料.     

N-Doped graphene quantum dot@mesoporous silica nanoparticles modified with hyaluronic acid for fluorescent imaging of tumor cells and drug delivery

The authors describe new bifunctional mesoporous silica nanoparticles (NPs) for specific targeting of tumor cells and for intracellular delivery of the cancer drug doxorubicin (DOX). Mesoporous silica nanoparticles (MSNPs) were coated with blue fluorescent N-graphene quantum dots, loaded with the drug DOX, and finally coated with hyaluronic acid (HA). Cellular uptake of the NPs with an architecture of the type HA-DOX-GQD@MSNPs enabled imaging of human cervical carcinoma (HeLa) cells via fluorescence microscopy. The cytotoxicity of the nanoparticles on HeLa cells was also assessed. The results suggest that the NPs are higher cytotoxicity effect and exert in living cell imaging ability. Compared to the majority of other drug nanocarrier systems, the one described here enables simultaneous DOX release and fluorescent monitoring.

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Graphical abstract Schematic of the bifunctional mesoporous silica nanoparticles were obtained via the Stöber method, along with the doxorubicin loaded and the hyaluronic acid capped. The sensor shows good specificity and significant cytotoxicity effect on Hela cells. (TEOS: tetraethyl orthosilicate; GQDs: graphene quantum dots; DOX: doxorubicin; HA: Hyaluronic acid).

     

Enhanced Anticancer Efficacy by ATP‐Mediated Liposomal Drug Delivery

A liposome‐based co‐delivery system composed of a fusogenic liposome encapsulating ATP‐responsive elements with chemotherapeutics and a liposome containing ATP was developed for ATP‐mediated drug release triggered by liposomal fusion. The fusogenic liposome had a protein–DNA complex core containing an ATP‐responsive DNA scaffold with doxorubicin (DOX) and could release DOX through a conformational change from the duplex to the aptamer/ATP complex in the presence of ATP. A cell‐penetrating peptide‐modified fusogenic liposomal membrane was coated on the core, which had an acid‐triggered fusogenic potential with the ATP‐loaded liposomes or endosomes/lysosomes. Directly delivering extrinsic liposomal ATP promoted the drug release from the fusogenic liposome in the acidic intracellular compartments upon a pH‐sensitive membrane fusion and anticancer efficacy was enhanced both in vitro and in vivo.