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1.
Adv Mater ; : e2202072, 2022 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-35580350

RESUMO

Surface oxygen vacancies have been widely discussed to be crucial for tailoring the activity of various chemical reactions from CO, NO, to water oxidation by using oxide-supported catalysts. However, the real role and potential function of surface oxygen vacancies in the reaction remains unclear because of their very short lifetime. Here, it is reported that surface oxygen vacancies can be well confined electrostatically for a polarization screening near the perimeter interface between Pt {111} nanocrystals and the negative polar surface (001) of ferroelectric PbTiO3. Strikingly, such a catalyst demonstrates a tunable catalytic CO oxidation kinetics from 200 °C to near room temperature by increasing the O2 gas pressure, accompanied by the conversion curve from a hysteresis-free loop to one with hysteresis. The combination of reaction kinetics, electronic energy loss spectroscopy (EELS) analysis, and density functional theory (DFT) calculations, indicates that the oxygen vacancies stabilized by the negative polar surface are the active sites for O2 adsorption as a rate-determining step, and then dissociated O moves to the surface of the Pt nanocrystals for oxidizing adsorbed CO. The results open a new pathway for tunable catalytic activity of CO oxidation.

2.
Bioact Mater ; 12: 143-152, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35310378

RESUMO

The induction of oxidative species, driven by oscillating electric field (E), has recently emerged as an effective approach for tumor inhibition, so-called electrodynamic therapy (EDT). While it offers a series of advantages attracting considerable attention, the fundamental mechanism and improvement strategies for EDT approach are being endeavored extensively with the aid of new material explorations. An interesting phenomenon observed in early studies is that the on-site concentration of chloride ion is highly favored for the induction of oxidative species and the efficacy of tumor inhibition. Following this discovery ignored previously, here for the first time, fine Pt/Cu alloy nanoparticles (PtCu3 NPs) are integrated with chloride ion transporter (CIT) for EDT-based combinational therapy. In this system, while PtCu3 NPs induce oxidative species under an electric field, it also effectively transforms endogenous H2O2 into •OH and consumes intracellular glutathione (GSH). More importantly, with the aid of CIT, PtCu3-PEG@CIT NPs promote the intracellular concentration of chloride ion (Cl-) by transporting extracellular Cl-, facilitating the generation of oxidative species considerably. Meanwhile, CIT delivered intracellularly increases lysosomal pH, leading to the disruption of cellular autophagy and weakening the treatment resistance. In consequence, significant tumor inhibition is enabled both in vitro and in vivo, due to the combination of unique characteristics offered by PtCu3-PEG@CIT.

3.
Biomater Sci ; 10(2): 376-380, 2022 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-34928270

RESUMO

Electrodynamic therapy (EDT) has recently emerged as an alternative approach for tumor therapy via the generation of ROS by platinum (Pt) nanoparticles under electric field. An interesting phenomenon observed during EDT is that the increased on-site concentration of chloride ions is highly beneficial for ROS generation and inhibition efficacy. Here, in this study, nanoclusters (KCC), consisting of potassium chloride (KCl) nanocrystals and amorphous calcium carbonate (CaCO3), were synthesized and integrated with platinum nanoparticles (KCCP). In this system, KCC can dissolve and release calcium and chloride ions within tumor cells. The intracellular chloride ions considerably facilitated ROS generation by Pt nanoparticles under an electric field. More importantly, the excessive calcium ions and ROS formed a cycle of mutual promotion and self-amplification in cells, leading to agitated tumor inhibition, both in vitro and in vivo.


Assuntos
Nanopartículas Metálicas , Nanopartículas , Neoplasias , Carbonato de Cálcio , Humanos , Neoplasias/tratamento farmacológico , Platina , Cloreto de Potássio
4.
J Nanobiotechnology ; 19(1): 358, 2021 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-34736483

RESUMO

Sonodynamic therapy (SDT), presenting spatial and temporal control of ROS generation triggered by ultrasound field, has attracted considerable attention in tumor treatment. However, its therapeutic efficacy is severely hindered by the intrinsic hypoxia of solid tumor and the lack of smart design in material band structure. Here in study, fine α-Fe2O3 nanoparticles armored with Pt nanocrystals (α-Fe2O3@Pt) was investigated as an alternative SDT agent with ingenious bandgap and structural design. The Schottky barrier, due to its unique heterostructure, suppresses the recombination of sono-induced electrons and holes, enabling superior ROS generation. More importantly, the composite nanoparticles may effectively trigger a reoxygenation phenomenon to supply sufficient content of oxygen, favoring the ROS induction under the hypoxic condition and its extra role played for ultrasound imaging. In consequence, α-Fe2O3@Pt appears to enable effective tumor inhibition with imaging guidance, both in vitro and in vivo. This study has therefore demonstrated a highly potential platform for ultrasound-driven tumor theranostic, which may spark a series of further explorations in therapeutic systems with more rational material design.


Assuntos
Antineoplásicos , Nanopartículas de Magnetita , Platina , Nanomedicina Teranóstica/métodos , Terapia por Ultrassom/métodos , Animais , Antineoplásicos/química , Antineoplásicos/farmacocinética , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Meios de Contraste/química , Meios de Contraste/farmacocinética , Feminino , Nanopartículas de Magnetita/química , Nanopartículas de Magnetita/toxicidade , Camundongos , Camundongos Endogâmicos BALB C , Platina/química , Platina/toxicidade , Ultrassonografia
5.
Biomater Sci ; 9(24): 8189-8201, 2021 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-34726680

RESUMO

Mitochondria are crucial metabolic organelles involved in tumorigenesis and tumor progression, and the induction of abnormal mitochondria metabolism is recognized as a strategy with strong potential for the exploration of advanced tumor therapeutics. Herein, hierarchical manganese silicate nanoclusters modified with triphenylphosphonium (MSNAs-TPP) were designed and synthesized for mitochondria-targeted tumor theranostics. The as-prepared MSNAs-TPP retains considerable dimensional and structural stability in the neutral physiological environment, favoring its accumulation at the tumor site. More interestingly, MSNAs-TPP may disassemble in a responsive manner to an acidic tumor microenvironment into ultrasmall manganese silicate nanocapsules (∼6 nm), enabling deep tumor penetration and mitochondria targeting. When reaching the mitochondria, the nanocapsules effectively deplete mitochondrial glutathione (GSH), and simultaneously release catalytic Mn2+ ions to induce amplified oxidative stress in the structure with the enriched CO2 and H2O2 from mitochondria metabolism. As a result, MSNAs-TPP presents considerable antitumor effect without a clear side effect, both in vitro and in vivo. The study may provide an alternative concept in the development of intelligent nanotherapeutics for tumor treatment with high efficacy.


Assuntos
Nanocápsulas , Neoplasias , Humanos , Peróxido de Hidrogênio , Imageamento por Ressonância Magnética , Mitocôndrias , Neoplasias/tratamento farmacológico , Microambiente Tumoral
6.
J Nanobiotechnology ; 19(1): 313, 2021 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-34641854

RESUMO

Nanoparticles, presenting catalytic activity to induce intracellular oxidative species, have been extensively explored for tumor treatment, but suffer daunting challenges in the limited intracellular H2O2 and thus suppressed therapeutic efficacy. Here in this study, a type of composite nanoparticles, consisting CaO2 core and Co-ferrocene shell, is designed and synthesized for combinational tumor treatment. The findings indicate that CaO2 core can be hydrolyzed to produce large amounts of H2O2 and calcium ions at the acidic tumor sites. Meanwhile, Co-ferrocene shell acts as an excellent Fenton catalyst, inducing considerable ROS generation following its reaction with H2O2. Excessive cellular oxidative stress triggers agitated calcium accumulation in addition to the calcium ions released from the particles. The combined effect of intracellular ROS and calcium overload causes significant tumor inhibition both in vitro and in vivo.


Assuntos
Cálcio/química , Peróxido de Hidrogênio , Nanopartículas/química , Animais , Linhagem Celular , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Feminino , Humanos , Peróxido de Hidrogênio/química , Peróxido de Hidrogênio/metabolismo , Peróxido de Hidrogênio/farmacologia , Camundongos , Camundongos Endogâmicos BALB C , Estresse Oxidativo/efeitos dos fármacos
7.
J Nanobiotechnology ; 19(1): 206, 2021 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-34246260

RESUMO

Electrodynamic therapy (EDT) has recently emerged as a potential external field responsive approach for tumor treatment. While it presents a number of clear superiorities, EDT inherits the intrinsic challenges of current reactive oxygen species (ROS) based therapeutic treatments owing to the complex tumor microenvironment, including glutathione (GSH) overexpression, acidity and others. Herein for the first time, iron oxide nanoparticles are decorated using platinum nanocrystals (Fe3O4@Pt NPs) to integrate the current EDT with chemodynamic phenomenon and GSH depletion. Fe3O4@Pt NPs can effectively induce ROS generation based on the catalytic reaction on the surface of Pt nanoparticles triggered by electric field (E), and meanwhile it may catalyze intracellular H2O2 into ROS via Fenton reaction. In addition, Fe3+ ions released from Fe3O4@Pt NPs under the acidic condition in tumor cells consume GSH in a rapid fashion, inhibiting ROS clearance to enhance its antitumor efficacy. As a result, considerable in vitro and in vivo tumor inhibition phenomena are observed. This study has demonstrated an alternative concept of combinational therapeutic modality with superior efficacy.


Assuntos
Antineoplásicos/química , Antineoplásicos/farmacologia , Compostos Férricos/química , Nanopartículas/química , Neoplasias/tratamento farmacológico , Platina/química , Animais , Catálise , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Terapia Combinada/métodos , Feminino , Glutationa , Peróxido de Hidrogênio/química , Cinética , Camundongos , Camundongos Endogâmicos BALB C , Nanopartículas/uso terapêutico , Espécies Reativas de Oxigênio , Microambiente Tumoral/efeitos dos fármacos
8.
Adv Mater ; 33(29): e2006836, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34096113

RESUMO

Macromolecular films are crucial functional materials widely used in the fields of mechanics, electronics, optoelectronics, and biology, due to their superior properties of chemical stability, small density, high flexibility, and solution-processing ability. Their electronic and mechanical properties, however, are typically much lower than those of crystalline materials, as the macromolecular films have no long-range structural ordering. The state-of-the-art for producing highly ordered macromolecular films is still facing a great challenge due to the complex interactions between adjacent macromolecules. Here, the growth of textured macromolecular films on a designed graphene/high-index copper (Cu) surface is demonstrated. This successful growth is driven by a patterned potential that originates from the different amounts of charge transfer between the graphene and Cu surfaces with, alternately, terraces and step edges. The textured films exhibit a remarkable improvement in remnant ferroelectric polarization and fracture strength. It is also demonstrated that this growth mechanism is universal for different macromolecules. As meter-scale graphene/high-index Cu substrates have recently become available, the results open a new regime for the production and applications of highly ordered macromolecular films with obvious merits of high production and low cost.

9.
Adv Sci (Weinh) ; 8(14): e2100241, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34032026

RESUMO

The conversion of endogenous H2 O2 into toxic hydroxyl radical (• OH) via catalytic nanoparticles is explored for tumor therapy and received considerable success. The intrinsic characteristics of microenvironment in tumor cells, such as limited H2 O2 and overexpressed glutathione (GSH), hinder the intracellular • OH accumulation and thus weaken therapeutic efficacy considerably. In this study, fine CaO2 nanoparticles with Cu-ferrocene molecules at the surface (CaO2 /Cu-ferrocene) are successfully designed and synthesized. Under an acidic condition, the particles release Ca2+ ions and H2 O2 in a rapid fashion, while they can remain stable in neutral. In addition, agitated production of • OH occurs following the Fenton reaction of H2 O2 and ferrocene molecules, and GSH is consumed by Cu2+ ions to avoid the potential • OH consumption. More interestingly, in addition to the exogenous Ca2+ released by the particles, the enhanced • OH production facilitates intracellular calcium accumulation by regulating Ca2+ channels and pumps of tumor cells. It turns out that promoted • OH induction and intracellular calcium overload enable significant in vitro and in vivo antitumor phenomena.


Assuntos
Cálcio/metabolismo , Cobre/metabolismo , Compostos Ferrosos/metabolismo , Glutationa/metabolismo , Metalocenos/metabolismo , Nanopartículas/uso terapêutico , Neoplasias/tratamento farmacológico , Peróxidos/metabolismo , Animais , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Modelos Animais de Doenças , Glutationa/efeitos dos fármacos , Camundongos
10.
Biomater Sci ; 9(7): 2598-2607, 2021 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-33595002

RESUMO

In this study, fine hollow nanocapsules, consisting of NiFe hydroxides (denoted as H-NiFe(OH)x), are designed and synthesized for the delivery of an anticancer drug (Doxorubicin, DOX) and tumour depletion. Owing to its fascinating characteristics of "Fe2+ preservation and regeneration", H-NiFe(OH)x presents considerable Fenton activity for hydroxyl radical (˙OH) induction. Efficient delivery of DOX is ensured due to its hollow microstructure, and a typical pH-responsive drug release is enabled. More importantly, the intracellular DOX, in addition to its intrinsic antitumour properties, induces extra exogenous H2O2 which favors the production of ˙OH by H-NiFe(OH)x in tumour cells. In consequence, remarkable in vitro and in vivo antitumour properties are successfully achieved. This drug delivery system is particularly inspirational to further studies in the exploration of intelligent therapeutic platforms for combinational tumour therapy.


Assuntos
Nanocápsulas , Neoplasias , Doxorrubicina/uso terapêutico , Sistemas de Liberação de Medicamentos , Humanos , Peróxido de Hidrogênio , Hidróxidos , Nanocápsulas/uso terapêutico , Neoplasias/tratamento farmacológico
11.
Nanotechnology ; 32(9): 095402, 2021 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-33157543

RESUMO

Silicon is considered as one of the most promising alternatives to the graphite anode for lithium-ion batteries due to its high theoretical capacity (4200 mAh g-1). However, its fragile solid electrolyte interphase cannot tolerate the large volume changes of bare silicon induced by the lithium insertion and extraction, resulting in low Coulombic efficiency. In previous reports, a yolk-shell design, such as Si@void@C, in which the well-defined space allows the silicon particles to expand freely without breaking the outer carbon shells, can effectively improve the Columbic efficiency. Here, we design a pomegranate-like silicon-based anodes self-assembled by the hollow-structured Si/void@C nanoparticles, in which silicon and some voids are together sealed in the outer carbon shells, by the magnesiothermic reduction of the colloidal SiO2@PEI nanospheres prepared by the hydrolysis of the tetraethoxysilane under the catalytic effect of polyetherimide (PEI). Due to the tolerance of the presealed void in the carbon shells of the primary hollow-structured Si/void@C nanoparticles, the prepared pomegranate-like silicon-based anodes deliver a high reversible capacity of 1615 mAh g-1 at 0.1 C and long cycle life of 73.5% capacity retention at 2 C after 500 cycles, as well as high Coulombic efficiency of 99%.

12.
RSC Adv ; 11(12): 7025-7036, 2021 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-35423197

RESUMO

We investigated the short- and medium-range structural features of sodium aluminosilicate glasses with various P2O5 (0-7 mol%) content and Al/Na ratios ranging from 0.667 to 2.000 by using molecular dynamics simulations. The local environment evolution of network former cations (Si, Al, P) and the extent of clustering behavior of modifiers (Na+) is determined through pair distribution function (PDF), total correlation function (TDF), coordination number (CN), Q x n distribution and oxygen speciation analysis. We show that Al-O-P and Si-O-Al linkage is preferred over other connections as compared to a random model and that Si-O-Si linkage is promoted by the P2O5 addition, which is related to structural heterogeneity and generates well-separated silicon-rich and aluminum-phosphorus-rich regions. Meanwhile, due to the relatively high propensity of Al to both Si and P, heterogeneity can be partly overcome with high Al content. A small amount of Si-O-P linkages have been detected at the interface of separated regions. Clustering of Na+ is also observed and intensified with the addition of P2O5. Based on the simulated structural information, a modified random network model for P2O5-bearing sodium aluminosilicate glass has been proposed, which could be useful to optimize the mobility of sodium ions and design novel functional glass compositions.

13.
J Biomed Nanotechnol ; 16(5): 640-651, 2020 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-32919484

RESUMO

Cellular starvation induced by glucose oxidase (GOx) had been extensively explored as a potential approach for tumor therapy. However, the therapeutic efficacy suffers daunting challenges due to the unsatisfactory intracellular transportation of GOx molecules. Herein for the first time, hydroxide nanoparticles with unique hollow microstructure (denoted as H-NiAl(OH)x) were designed and synthesized for GOx delivery. In this system, despite its intrinsic degradation properties in acidic tumor microenvironment, Ni2+ ions released during degradation may catalyze a Fenton reaction to induce considerable production of cytotoxic hydroxyl radicals (OH). The cavity of hollow nanocapsules provides large surface area, and favors GOx capsulation and delivery. The findings indicate the intracellular glucose can be effectively consumed by GOx transported, and the reaction products consisting of acid and H2O2 facilitate the OH induction of nanocapsules in a synergistic manner. Both in vitro and in vivo antitumor properties have been consequently achieved by H-NiAl(OH)x/GOx systems. This study offering catalytic nanocapsules based on Ni2+ ions may spark a series of follow-on explorations in constructing drug delivery and therapeutic systems for synergistic tumor treatment.


Assuntos
Nanocápsulas , Nanopartículas , Glucose Oxidase , Peróxido de Hidrogênio , Radical Hidroxila
14.
Adv Sci (Weinh) ; 7(17): 2001223, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32995127

RESUMO

Glucose-oxidase (GOx)-mediated starvation by consuming intracellular glucose has aroused extensive exploration as an advanced approach for tumor treatment. However, this reaction of catalytic oxidation by GOx is highly dependent on the on-site oxygen content, and thus starvation therapy often suffers unexpected anticancer outcomes due to the intrinsic tumorous hypoxia. Herein, porous platinum nanospheres (pPts), incorporated with GOx molecules (PtGs), are synthesized to enable synergistic cancer therapy. In this system, GOx can effectively catalyze the oxidation of glucose to generate H2O2, while pPt triggers the decomposition of both endogenous and exogenous H2O2 to produce considerable content of O2 to facilitate the glucose consumption by GOx. Meanwhile, pPt induces remarkable content of intracellular reactive oxygen species (ROS) under an alternating electric field, leading to cellular oxidative stress injury and promotes apoptosis following the mechanism of electrodynamic therapy (EDT). In consequence, the PtG nanocomposite exhibits significant anticancer effect both in vitro and in vivo. This study has therefore demonstrated a fascinating therapeutic platform enabling oxygen-inductive starvation/EDT synergistic strategy for effective tumor treatment.

15.
ACS Appl Mater Interfaces ; 12(37): 41323-41332, 2020 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-32830944

RESUMO

All-solid-state lithium batteries (ASSLBs) have been paid increasing attention because of the better security compared with conventional lithium-ion batteries with flammable organic electrolytes. However, the poor ion transport between the cathode materials greatly hinders the capacity performance of ASSLBs. Herein, an electron/ion dual-conductive electrode framework is proposed for superior performance ASSLBs. Highly electronic conductive reduced graphene oxide and carbon nanotubes interconnect with active materials in the cathodes, constructing a three-dimensional continuous electron transport network. The composite electrolyte penetrates into the porous structure of the electrode, forming a consecutive ionic conductive framework. Furthermore, the thin electrolyte film formed on the surface of the cathode effectively lowers the interfacial resistance with the electrolyte membrane. Highly electron/ion conductive electrodes, combined with the polyethylene oxide-Li6.4La3Zr1.4Ta0.6O12 (PEO-LLZTO) composite electrolyte, show excellent capacity performance for both LiFePO4 and sulfur (lithium-sulfur battery) active materials. In addition, the LiFePO4 cathode demonstrates superior capacity performance and rate capability at room temperature. Furthermore, the relationship between the low Coulombic efficiency and Li dendrite growth has been revealed in this work. An effective layer is formed on the surface of Li metal by the simple modification of cupric fluoride (CuF2), which can stabilize the electrolyte/anode interface. Finally, high-performance ASSLBs with high Coulombic efficiency can be achieved.

16.
J Mater Chem B ; 8(37): 8546-8557, 2020 09 30.
Artigo em Inglês | MEDLINE | ID: mdl-32840278

RESUMO

Amino acids are the fundamental building blocks of proteins in tumor cells. The consumption of amino acid can be an effective approach for destroying the tumor cytoskeleton and malfunctioning of the intracellular metabolic balance. Following this concept, herein, amino acid oxidase (AAO) is delivered by hollow Fe3+/tannic acid nanocapsules (HFe-TA) and incorporated within the cancer cell membrane (M) for the first time for synergistic tumor therapy. In this system (M@AAO@HFe-TA), the intracellularly delivered AAO molecules catalyze the oxidative deamination effectively and consume amino acids significantly. The upregulation of intracellular acid and H2O2 concentration facilitates the HFe-TA mediated Fenton reaction and enhances the induction of cytotoxic ˙OH. With the combined effects, considerable in vitro and in vivo tumor inhibition was achieved by M@AAO@Fe-TA due to the activated Bcl-2/Bax/Cyt C/caspase 3 mitochondrial apoptotic pathway. This study offers an alternative therapeutic platform, functioning as a biomimetic cascade nanozyme, to enable synergistic starvation and chemodynamic tumor therapy with high efficacy.


Assuntos
Antineoplásicos/uso terapêutico , Membrana Celular/química , Portadores de Fármacos/química , L-Aminoácido Oxidase/uso terapêutico , Nanocápsulas/química , Neoplasias/tratamento farmacológico , Animais , Linhagem Celular Tumoral , Feminino , Peróxido de Hidrogênio/metabolismo , Ferro/química , Camundongos Endogâmicos BALB C , Taninos/química
17.
Theranostics ; 10(17): 7671-7682, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32685012

RESUMO

Abnormal tumor microenvironment, such as hypoxia, interstitial hypertension and low pH, leads to unexpected resistance for current tumor treatment. The development of versatile drug delivery systems which present responsive characteristics to tumor microenvironment (TME) has been extensively carried out, but remains challenging. In this study, zeolitic imidazolate framework-8 (ZIF-8) coated ZnS nanoparticles have been designed and prepared for co-delivery of ICG/TPZ molecules, denoted as ZSZIT, for H2S-amplified synergistic therapy. Methods: The ZSZ nanoparticles were characterized using SEM, TEM and XRD. The in vitro viabilities of cancer cells cultured with ZSZIT under normoxia/hypoxia conditions were evaluated by cell counting kit-8 (CCK-8) assay. In addition, in vivo anti-tumor effect was also performed using male Balb/c nude mice as animal model. Results: ZSZIT shows cascade PDT and hypoxia-activated chemotherapeutic effect under an 808nm NIR irradiation. Meanwhile, ZSZIT degrades under tumor acidic environment, and H2S produced by ZnS cores could inhibit the expression of catalase, which subsequently favors the hypoxia and antitumor effect of TPZ drug. Both in vitro and in vivo studies demonstrate the H2S-sensitized synergistic antitumor effect based on cascade PDT/chemotherapy. Conclusion: This cascade H2S-sensitized synergistic nanoplatform has enabled more effective and lasting anticancer treatment.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Portadores de Fármacos/química , Nanopartículas Metálicas/química , Neoplasias/tratamento farmacológico , Fotoquimioterapia/métodos , Animais , Protocolos de Quimioterapia Combinada Antineoplásica/farmacocinética , Linhagem Celular Tumoral , Composição de Medicamentos/métodos , Sinergismo Farmacológico , Humanos , Sulfeto de Hidrogênio/química , Verde de Indocianina/administração & dosagem , Masculino , Estruturas Metalorgânicas/química , Camundongos , Neoplasias/patologia , Pró-Fármacos/administração & dosagem , Pró-Fármacos/farmacocinética , Tirapazamina/administração & dosagem , Hipóxia Tumoral/efeitos dos fármacos , Microambiente Tumoral/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto , Zeolitas/química
18.
Biomaterials ; 255: 120202, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32562941

RESUMO

Overexpression of P-glycoprotein (P-gp), which is responsible for pumping chemotherapeutic drugs out of tumor cells, has been recognized as an important cause of drug resistance in conventional chemotherapy. Herein, porous platinum nanoparticles (pPt NPs) are developed to enable the combined electrodynamic therapy (EDT) with chemotherapy. With polyethylene glycol (PEG) coating, the obtained pPt-PEG NPs could be loaded with anticancer drug doxorubicin (DOX) by utilizing the porous structure of pPt NPs. Those pPt-PEG NPs are able to produce reactive oxygen species (ROS) by triggering water decomposition under electric field, independent of O2 and H2O2 contents in the tumor. Furthermore, the ROS generated during EDT could induce the inhibition of P-glycoprotein (P-gp), in turn enhancing the efficacy of chemotherapeutic agents by facilitating intracellular accumulation of drugs. As the results, excellent synergetic therapeutic effects were observed by combining chemotherapy with EDT using DOX-loaded pPt (DOX@pPt-PEG) NPs, as demonstrated by both in vitro and in vivo experiments. This study demonstrates a new concept of combinational cancer therapy with superior therapeutic efficacy.


Assuntos
Nanopartículas Metálicas , Nanopartículas , Linhagem Celular Tumoral , Doxorrubicina , Peróxido de Hidrogênio , Platina , Porosidade
19.
Biomater Sci ; 8(14): 3844-3855, 2020 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-32555791

RESUMO

Nanoparticles presenting promoted catalytic activity, oxygen induction and loading capability are in high demand for effective synergistic tumor therapy. Herein, ferric-tannic acid complex nanocapsules with fine hollow microstructure (HFe-TA) are synthesized and loaded with a photosensitizer (indocyanine green, ICG) for synergistic tumor therapy. In acidic environment, ICG@HFe-TA decomposes and releases Fe3+ ions, TA and ICG molecules. Fe3+, with low catalytic activity, is effectively converted into highly catalytic Fe2+ by the reductant TA, enabling promoted efficacy of ˙OH induction. More importantly, the ROS (1O2) induction by ICG is significantly enhanced under 808 nm laser irradiation due to the O2 byproduct of Fe3+/Fe2+ conversion. In consequence, the ICG@HFe-TA nanoparticles exhibit considerable in vitro and in vivo tumor inhibition owing to the combined effect of ˙OH and 1O2 induced intracellularly. This study has therefore demonstrated a potential platform enabling combined photodynamic and chemodynamic therapy with high efficacy.


Assuntos
Nanocápsulas , Neoplasias , Fotoquimioterapia , Humanos , Nanocápsulas/uso terapêutico , Neoplasias/tratamento farmacológico , Fármacos Fotossensibilizantes/uso terapêutico , Espécies Reativas de Oxigênio , Taninos
20.
Adv Sci (Weinh) ; 7(7): 1903512, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32274323

RESUMO

Therapeutic systems to induce reactive oxygen species (ROS) have received tremendous success in the research of tumor theranostics, but suffered daunting challenges in limited efficacy originating from low presence of reactants and reaction kinetics within cancer cells. Here, ferrous sulfide-embedded bovine serum albumin (FeS@BSA) nanoclusters, in an amorphous nature, are designed and synthesized via a self-assembly approach. In acidic conditions, the nanoclusters degrade and simultaneously release H2S gas and Fe2+ ions. The in vitro study using Huh7 cancer cells reveals that Fe2+ released from FeS@BSA nanoclusters induces the toxic hydroxyl radical (·OH) effectively via the Fenton reaction. More interestingly, H2S gas released intracellularly presents the specific suppression effect to catalase activity of cancer cells, resulting in the promoted presence of H2O2 that facilitates the Fenton reaction of Fe2+ and consequently promotes ROS induction within the cells remarkably. After intravenous administration, the nanoclusters accumulate in the tumors of mice via the enhanced permeability and retention effect and present strong magnetic resonance imaging (MRI) signals. The findings confirm this therapeutic system can enable superior anti-tumor performance with MRI guidance and negligible side effects. This study, therefore, offers an alternative gas-amplified ROS-based therapeutic platform for synergetic tumor treatment.

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