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1.
Front Bioeng Biotechnol ; 11: 1298723, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38033822

RESUMO

Introduction: Smart elastomers, which possess self-healing and shape memory capabilities, have immense potential in the field of biomedical applications. Polycarbonates and polyesters have gained widespread interest due to their remarkable biocompatibility over the last century. Nevertheless, the lack of functional versatility in conventional polyesters and polycarbonates means that they fall short of meeting the ever-evolving demands of the future. Methods: This paper introduced a new smart elastomer, named mPEG43-b-(PMBC-co-PCL)n, developed from polyester and polycarbonate blends, that possessed shape memory and self-heal capabilities via a physical crosslinking system. Results: The material demonstrated a significant tensile strength of 0.38 MPa and a tensile ratio of 1155.6%, highlighting its favorable mechanical properties. In addition, a conspicuous shape retrieval rate of 93% was showcased within 32.5 seconds at 37°C. Remarkably, the affected area could be repaired proficiently with no irritation experienced during 6h at room temperature, which was indicative of an admirable repair percentage of 87.6%. Furthermore, these features could be precisely modified by altering the proportion of MBC and ε-CL to suit individual constraints. Discussion: This innovative elastomer with exceptional shape memory and self-heal capabilities provides a solid basis and promising potential for the development of self-contracting intelligent surgical sutures in the biomedical field.

2.
Environ Sci Pollut Res Int ; 30(42): 96554-96561, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37578587

RESUMO

In this study, we have utilized corn bract, a green agricultural by-product, as a carrier. It is subsequently modified with zinc sulfide to synthesize an efficient composite material termed as corn bract/polydopamine@zinc sulfide (CB/PDA@ZnS). This novel composite demonstrates significant potential for biomass removal of mercury ions (Hg(II)). The composition, structure, and morphology of CB/PDA@ZnS composites are characterized by Fourier transform infrared (FT-IR) spectrum, thermogravimetric analysis (TGA), X-ray powder diffraction (XRD), and scanning electron microscope (SEM). The effect of pH value, adsorbent dosage, initial Hg(II) concentration, adsorption time and temperature, and coexistence ions on the adsorption behavior is investigated. The results show that CB/PDA@ZnS can efficiently remove Hg(II) from water with uptake capacities of 333.03 mg/g and removal efficiency of 99.91% under an optimal conditions (pH of 3, the adsorbent dosage of 0.015 g, contact time of 90 min, and initial concentration of 100 mg/L) at room temperature. The fitting analysis of the experimental data reveals that the adsorption process of Hg(II) follows the quasi-secondary adsorption kinetic model as well as the Langmuir isothermal adsorption model, which is a spontaneous heat absorption process. In addition, the composite adsorbent obtained exhibit excellent selectivity for Hg(II) ions and anti-coexisting ion interference performance. After five cycles of adsorption-desorption experiments, the corresponding adsorption capacity is 331.11 mg/g, accounting for 93.33% of the first adsorption capacity, indicating that the adsorbent has excellent regeneration performance. The stability of the adsorbent and the adsorption mechanism of Hg(II) ion are systematically discussed using FT-IR, XRD, and X-ray photoelectron spectroscopy (XPS). Finally, this adsorbent is tested for the removal of industrial wastewater containing Hg(II), and the adsorption and removal efficiency are 331.67 mg/g and 99.50%, respectively. This study provides a very valuable information for future Hg(II) removal from aqueous solutions.


Assuntos
Mercúrio , Poluentes Químicos da Água , Mercúrio/análise , Zea mays , Dopamina/análise , Espectroscopia de Infravermelho com Transformada de Fourier , Água , Adsorção , Cinética , Poluentes Químicos da Água/análise , Concentração de Íons de Hidrogênio
3.
Colloids Surf B Biointerfaces ; 226: 113310, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37054465

RESUMO

The size of the nanoparticles is moderate and the dispersion is well, which will not be recognized nonspecifically and clearance by the endothelial reticular system. In this study, stimuli-responsive polypeptides nano-delivery system has been constructed, which can realize the response to various stimuli in the tumor microenvironment. Tertiary amine groups are grafted to the side chain of polypeptides as the point of charge reversal and particle expansion. In addition, a new kind of liquid crystal monomer was prepared by substituting cholesterol-cysteamine, which can promote polymers to realize the transformation of spatial conformation by adjusting the ordered arrangement of macromolecules. The introduction of hydrophobic elements greatly enhanced the self-assembly performance of polypeptides, which could effectively improve the drug loading and encapsulation rate of nanoparticles. Nanoparticles could achieve targeted aggregation in tumor tissues, and there were no toxicity and side effects on normal bodies during treatment, with good safety in vivo.


Assuntos
Doxorrubicina , Nanopartículas , Doxorrubicina/química , Sistemas de Liberação de Medicamentos , Nanopartículas/uso terapêutico , Nanopartículas/química , Polímeros/química , Peptídeos/química , Concentração de Íons de Hidrogênio , Portadores de Fármacos/química , Liberação Controlada de Fármacos , Linhagem Celular Tumoral
4.
Environ Sci Pollut Res Int ; 30(25): 67059-67070, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37103700

RESUMO

In this study, ZnS nanoparticles were loaded on the surface of zeolite NaA and embedded in a carbon aerogel to prepare C@zeolite-ZnS, where zeolite NaA was used in order to adsorb Zn2+ ions released during ion exchange, and the carbon aerogel had good dispersion as a carrier for ZnS to solve the ZnS agglomeration problem. The morphology and structure of C@zeolite-ZnS were characterized by FT-IR, XRD, SEM, BET, and XPS. C@zeolite-ZnS showed excellent selectivity and high removal rate for Hg(II) ions with a maximum adsorption capacity of 795.83 mg/g. When the pH, adsorption time, and Hg(II) ion concentration were 6, 30 min, and 25 mg/L at 298 K, the corresponding adsorption and removal rates reached 99.90% and 124.88 mg/g, respectively. Thermodynamic studies have shown that the adsorption process is a spontaneous heat absorption process. Furthermore, after up to 10 cycles of adsorption, the adsorbent still exhibited outstanding stability and high adsorption capacity with removal rates exceeding 99%. In conclusion, C@zeolite-ZnS, which is stable and reusable and has the ability to meet industrial emission standards after adsorption of Hg(II) ions, is very promising for industrial applications.


Assuntos
Mercúrio , Zeolitas , Zeolitas/química , Amido , Espectroscopia de Infravermelho com Transformada de Fourier , Sulfetos/química , Carbono
5.
Colloids Surf B Biointerfaces ; 224: 113232, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36868182

RESUMO

A series of novel poly(amino acid)s materials were designed to prepare drug-loaded nanoparticles by physical encapsulation and chemical bonding. The side chain of the polymer contains a large number of amino groups, which effectively increases the loading rate of doxorubicin (DOX). The structure contains disulfide bonds that showing a strong response to the redox environment, which can achieve targeted drug release in the tumor microenvironment. Nanoparticles mainly present spherical morphology with the suitable size for participating in systemic circulation. cell experiments demonstrate the non-toxicity and good cellular uptake behavior of polymers. In vivo anti-tumor experiments shows nanoparticles could inhibit tumor growth and effectively reduce the side effects of DOX.


Assuntos
Nanopartículas , Neoplasias , Humanos , Sistemas de Liberação de Medicamentos , Preparações de Ação Retardada/farmacologia , Aminoácidos , Sistemas de Liberação de Fármacos por Nanopartículas , Doxorrubicina/farmacologia , Doxorrubicina/química , Polímeros/química , Portadores de Fármacos/química , Nanopartículas/química , Oxirredução , Concentração de Íons de Hidrogênio , Microambiente Tumoral
6.
Drug Deliv Transl Res ; 13(9): 2394-2406, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-36913103

RESUMO

Enhancing tissue permeability and achieving drug aggregation is the key to targeted tumor therapy. A series triblock copolymers of poly(ethylene glycol)-poly(L-lysine)-poly(L-glutamine) were synthesized by ring-opening polymerization, and charge-convertible nano-delivery system was constructed by loading doxorubicin (DOX) with 2-(hexaethylimide) ethanol on side chain. In normal environment (pH = 7.4), the zeta potential of the drug-loaded nanoparticle solution is negative, which is conducive to avoiding the identification and clearance of nanoparticles by the reticulo-endothelial system, while potential-reversal can be achieved in the tumor microenvironment, which effectively promotes cellular uptake. Nanoparticles could effectively reduce the distribution of DOX in normal tissues and achieve targeted aggregation at tumor sites, which can effectively improve the antitumor effect, while would not causing toxicity and damage to normal body.


Assuntos
Nanopartículas , Neoplasias , Humanos , Aminoácidos , Sistemas de Liberação de Medicamentos , Preparações de Ação Retardada , Doxorrubicina/química , Nanopartículas/química , Neoplasias/tratamento farmacológico , Concentração de Íons de Hidrogênio , Portadores de Fármacos/química , Microambiente Tumoral
7.
RSC Adv ; 13(5): 3155-3163, 2023 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-36756444

RESUMO

Notwithstanding the rapid development of suture elastomers to meet the needs of practical surgery, utilizing the elastomers' self-healing function as a surgical suture to facilitate the healing of wounds has not been addressed. Here, a biodegradable aliphatic polycarbonate smart elastomer, mPEG113-b-PMBC n , was synthesized from aliphatic polycarbonate monomer with methoxy polyethylene glycol (mPEG113, 5.0 kDa) as initiator, which exhibited excellent mechanical properties, highly efficient self-repairing, and remarkable shape memory behavior. The polymers possess outstanding self-healing ability for 150 min. Meanwhile, after 46.33 ± 1.18 s, the temporary shape of the obtained polymer had been recovered. The results of biocompatibility tests reveal that the polymers have excellent biocompatibility and can be regarded as good biomedical materials. Then, in vivo experiments were used to prove the self-healing knotting ability of the polymers and quickly close a wound surface using a programmed shape at physiological temperature. The results demonstrated that the injury wound can be effectively healed compared with traditional sutures, which will offer new study suggestions for subsequent healing areas.

8.
Water Sci Technol ; 87(2): 469-491, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36706294

RESUMO

To mitigate the environmental hazards of boron mud waste accumulation, we prepared environmental-friendly SiO2 aerogels by extracting them through alkaline leaching treatment and optimized the experimental conditions. The optimum process parameters for alkaline leaching solution NaOH concentration, leaching temperature, solid-to-liquid ratio, and leaching time were 2 mol/L, 95 °C, 1:4, and 3 h, respectively. In this work, cheap and non-toxic hydroxy silicone oil (PDMS-OH) and hydrogen-containing silicone oil (PMHS) were used as surface modifiers instead of toxic and expensive trimethylchlorosilane (TMCS) in the SiO2 aerogel modification process. The best performance under the optimum conditions was achieved with 60% PDMS-OH-modified SiO2 aerogel. Organic liquid spills, represented by toluene, pose a great danger to the environment and water bodies. We treated free toluene on the water surface with the aerogel mentioned above and its adsorption capacity was up to 2,655 mg/g. After the adsorption of toluene, the aerogels coalesced into agglomerates for subsequent collection and handling. Furthermore, after five repeated applications, the adsorption capacity remained at 91.43% of the initial application. Overall, this research provided an inexpensive and simple solution for the treatment of organic liquids in wastewater.


Assuntos
Boro , Tolueno , Dióxido de Silício , Adsorção , Óleos de Silicone , Água
9.
J Mater Chem B ; 10(44): 9266-9279, 2022 11 16.
Artigo em Inglês | MEDLINE | ID: mdl-36342458

RESUMO

Nanotechnology-mediated drug delivery systems suffer from insufficient retention in tumor tissues and unreliable drug release at specific target sites. Herein, we developed an epidermal growth factor receptor-targeted multifunctional micellar nanoplatform (GE11-DOX+CEL-M) by encapsulating celecoxib into polymeric micelles based on the conjugate of GE11-poly(ethylene glycol)-b-poly(trimethylene carbonate) with doxorubicin to suppress tumor growth and metastasis. The polymeric micelles maintained stable nanostructures under physiological conditions but quickly disintegrated in a weakly acidic environment, which is conducive to controlled drug release. Importantly, GE11-DOX+CEL-M micelles effectively delivered the drug combination to tumor sites and enhanced tumor cell uptake through GE11-mediated active tumor targeting. Subsequently, GE11-DOX+CEL-M micelles dissociated in response to intracellular slightly acidic microenvironmental stimuli, resulting in rapid release of celecoxib and doxorubicin to synergistically inhibit the proliferation and migration of tumor cells. Systemic administration of GE11-DOX+CEL-M micelles into mice bearing subcutaneous 4T1 tumor models resulted in higher tumor growth suppression and decreased lung metastasis of tumor cells compared with micelles without GE11 decoration or delivering only doxorubicin. Furthermore, the micelles effectively reduced the systemic toxicity of the chemotherapy drugs. This nanotherapeutic system provides a promising strategy for safe and effective cancer therapy.


Assuntos
Micelas , Neoplasias , Camundongos , Animais , Celecoxib/farmacologia , Linhagem Celular Tumoral , Doxorrubicina , Polímeros , Neoplasias/tratamento farmacológico
10.
RSC Adv ; 12(49): 31792-31800, 2022 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-36380957

RESUMO

As known, mercury contamination is one of the current environmental issues due to the high toxicity of mercury. Corn bract (CB) is an agricultural by-product, and its final treatment is generally incineration that causes air pollution. In this study, a new type of high-efficiency biomass adsorbent (CB@MoS2) for adsorption of Hg(ii) was obtained, and its morphology and structure were characterized with FT-IR, XRD, SEM and TEM. The results showed that when the pH value, Hg(ii) ion concentration and adsorption time were 4, 100 mg L-1 and 120 min, the adsorption capacity and removal rate could reach 332.50 mg g-1 and 99.75%. In addition, CB@MoS2 had a good selectivity for Hg(ii) ions. The adsorption behavior followed pseudo-second-order kinetics, indicating that the adsorption of Hg(ii) ions by CB@MoS2 was a chemical adsorption. After five adsorption-desorption experiments, it still possessed good adsorption performance and effective regeneration. In short, CB@MoS2 has high efficiency and good reusability, and will become a candidate material for the treatment of mercury-containing industrial wastewater.

11.
Water Sci Technol ; 86(3): 496-510, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35960833

RESUMO

Microporous organic polymers (MOPs) possessing large specific surface area with high stability are suitable adsorbent to remove contaminants from water, such as organic pollutant and heavy metal contaminants. Herein, a phenanthroline-based microporous organic polymer (Phen-MOP) has been synthesized through the coupling between benzene and 1,10-phenanthroline. The adsorption kinetics and thermodynamics were investigated. This Phen-MOP exhibited good adsorption efficiency for removal of Cu(II) from water with high structural stability and reusability. The maximum removal efficiency could reach to 98.47% at a Cu(II) concentration of 20 mg/L, pH = 7, 25 °C. It was found by investigating the adsorption isotherms that the maximum adsorption capacity Qm was 128.53 mg/g. Interestingly, after the adsorption of Cu(II), the resulting Phen-MOP-Cu can serve as an efficient heterogeneous catalyst for the Ullmann-type reaction. The structure and composition of the Phen-MOP-Cu were characterized by Fourier transform infrared (FT-IR), X-ray diffraction (XRD), thermogravimetric analysis (TGA), Brunauer-Emmett-Teller (BET), scanning electron microscope (SEM), energy-dispersive X-ray spectroscopy (EDX) and X-ray photoelectron spectroscopy (XPS). The results indicated that this catalyst possessed immense specific surface area, large pore volume and high stability. The catalyst was easily recyclable and did not significantly lose catalytic activity after being reused six times.


Assuntos
Fenantrolinas , Poluentes Químicos da Água , Adsorção , Concentração de Íons de Hidrogênio , Cinética , Fenantrolinas/análise , Polímeros , Espectroscopia de Infravermelho com Transformada de Fourier , Água , Poluentes Químicos da Água/química
12.
Environ Sci Pollut Res Int ; 29(56): 84287-84299, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35780271

RESUMO

Iron-sulfur nano compounds have been proven to be effective in mercury removal, but the agglomeration, poor dispersion and mobility, and easy oxidation challenges limit their application. Herein, carbon black originating from pyrolysis of waste tires was used as a carrier of nano-FeS to obtain an efficient adsorbent (C@PDA-FeS). It is found that the C@PDA-FeS shows outstanding adsorption ability, excellent selectivity, and high removal rate. A maximum adsorption capacity of 1754 mg/g is obtained, and the residual Hg(II) ion concentration is as low as 3.2 µg/L in the simulated industrial wastewater, which meets the industrial discharge standard under the optimal conditions. Meanwhile, the removal rate of Hg(II) ion can reach 99.8% after up to 10 cycles. More importantly, the C@PDA-FeS still shows good adsorption efficiency, and the removal rate of Hg(II) ion is over 99% (25 mg/L Hg(II) concentration) after 90 days of storage, demonstrating the long-term stability and promising future of the adsorbent. In addition, the waste adsorbent (C@PDA-FeS/HgS) is reused as a photocatalyst to degrade methylene blue, and the corresponding degradation rate is 92.9% (10 mg/L).


Assuntos
Mercúrio , Poluentes Químicos da Água , Fuligem , Pirólise , Poluentes Químicos da Água/análise , Cinética , Mercúrio/análise , Águas Residuárias/análise , Adsorção , Concentração de Íons de Hidrogênio
13.
Small ; 18(18): e2200439, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35355393

RESUMO

The intercrystalline interfaces have been proven vital in heterostructure catalysts. However, it is still challenging to generate specified heterointerfaces and to make clear the mechanism of a reaction on the interface. Herein, this work proposes a strategy of Fe-catalyzed cascade formation of heterointerfaces for comprehending the hydrogen evolution reaction (HER). In the pure solid-phase reaction system, Fe catalyzes the in situ conversion of MoO2 to MoC and then Mo2 C, and the consecutive formation leaves lavish intercrystalline interfaces of MoO2 -MoC (in Fe-MoO2 /MoC@NC) or MoC-Mo2 C (in Fe-MoC/ß-Mo2 C@NC), which contribute to HER activity. The improved HER activity on the interface leads to further checking of the mechanism with density functional theory calculation. The computation results reveal that the electroreduction (Volmer step) produced H* prefers to be adsorbed on Mo2 C; then two pathways are proposed for the HER on the interface of MoC-Mo2 C, including the single-molecular adsorption pathway (Rideal mechanism) and the bimolecular adsorption pathway (Langmuir-Hinshelwood mechanism). The calculation results further show that the former is favorable, and the reaction on the MoC-Mo2 C heterointerface significantly lowers the energy barriers of the rate-determining steps.


Assuntos
Hidrogênio , Ferro , Catálise , Hidrogênio/química , Molibdênio/química
14.
Int J Biol Macromol ; 206: 232-241, 2022 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-35157903

RESUMO

In this study, the metal-organic framework ZIF-8 has been successfully planted on the surface of chitosan microspheres (CS/PDA@ZIF-8) using polydopamine as connecting material for the first time, which avoids the use of expensive, non-renewable, and non-biodegradable polystyrene microspheres commonly used as templates to prepare core-shell structures. Moreover, the metal-organic framework ZIF-8 was prepared specially by three different methods and all characterized by SEM, TEM, and BET, and the ZIF-8 shell prepared at room temperature presents a regular morphology, uniform size, large specific surface area (353.1 m2/g) than the shells prepared by the other methods including. The CS/PDA@ZIF-825@Pd with high catalytic activity and high stability was especially prepared by encapsulating Pd nanoparticles into the pores of CS/PDA@ZIF-825. Notably, the fabricated catalyst performed well in an array of reactions, for example the Kapp value of the p-nitrophenol reduction reaction reached 0.0426 s-1, and the TOF of the Suzuki coupling reaction reached 128 h-1. In addition, the ZIF-67, UiO-66, UiO-66-NH2, HKUST-1, and NH2-MIL-53(Al) were also grown on chitosan microcapsules successively to prepare the core-shell microspheres, which prove the universal applicability of this strategy. And beyond that, the introduction of chitosan microspheres endows the material with biodegradable properties and excellent recycling properties.


Assuntos
Quitosana , Estruturas Metalorgânicas , Catálise , Quitosana/química , Microesferas , Nitrofenóis , Paládio/química , Ácidos Ftálicos
15.
Int J Biol Macromol ; 184: 358-368, 2021 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-34126154

RESUMO

In this study, an environmental-friendly palladium catalyst with high efficiency, magnetic, recoverability, reusability, and excellent stability was prepared and thoroughly characterized by the Fourier transform infrared spectroscopy (FT-IR), Scanning electron microscopy (SEM), X-ray diffraction (XRD), Elemental mapping, Thermogravimetric analysis (TGA) and Energy-dispersive X-ray spectroscopy (EDX). Results demonstrates that melamine provides a coordination point on the surface of chitosan microspheres, which provides a platform for the uniform distribution of palladium (II) and combines with palladium (II) firmly to avoid unnecessary leaching of nanoparticles. Besides, Fe3O4/CS-Me@Pd microcapsules exhibited high catalytic performance in reducing p-NP in water at room temperature (150-300 s). This composite was also effective in the Suzuki-Miyaura coupling reaction under mild conditions with high catalytic performance (TON = 3.8 × 104, TOF = 7.6 × 104). Reproducibility experiments also showed that Fe3O4/CS-Me@Pd microcapsules have high recovery efficiency and can work at least six times during these two catalytic reactions. The hot filtration test indicated that the catalyst has heterogeneous nature.


Assuntos
Quitosana/química , Nitrofenóis/química , Paládio/química , Triazinas/química , Água/química , Cápsulas , Catálise , Química Verde , Fenômenos Magnéticos , Microscopia Eletrônica de Varredura , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios X
16.
Int J Biol Macromol ; 182: 1120-1129, 2021 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-33892041

RESUMO

In this study, a new tannic acid cross-linking cellulose/polyethyleneimine functionalized magnetic composite (MCP) as a biomass adsorbent of Hg(II) ions was prepared. The morphology and structure of MCP were characterized with FT-IR, TG, XRD, SEM and TEM. The effect of the different factors such as pH, contact time, initial Hg(II) ion concentration, and adsorption temperature on the adsorption behavior was investigated. The results showed that MCP exhibited an excellent selectivity and reutilization, fast removal rate, and very high adsorption capacity. The corresponding adsorption capacity and removal rate of could reach 99.00% and 247.51 mg/g when the pH value, adsorption time, Hg(II) ion concentration were 5, 180 min and 100 mg/L at 293 K. The kinetics followed the pseudo-second-order, which indicated that the adsorption behavior of MCP for Hg(II) ion belonged to the chemical adsorption process and external diffusion. The thermodynamic study showed that the adsorption process was a spontaneous and exothermic process. After the fifth adsorption-desorption experiment, it still had better adsorption performance and reutilization. All in all, MCP with highly stable and efficient, as well as excellent reusability will be a candidate for industry-level applications from wastewater with Hg(II) ions.


Assuntos
Celulose/análogos & derivados , Polietilenoimina/análogos & derivados , Taninos/química , Adsorção , Celulose/química , Concentração de Íons de Hidrogênio , Polietilenoimina/química , Termodinâmica
17.
Acta Biomater ; 118: 182-195, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33045399

RESUMO

Stimulus-responsive nanosystem is a powerful method to improve the bioavailability and reduce the side effects of anticancer agents. In the present study, a customized dual pH-responsive micellar nanoplatform (DOX+LAP-M) based on polycarbonate-doxorubicin conjugate micelles was prepared to co-deliver the chemotherapeutic agent lapatinib for inhibiting tumor growth and metastasis. DOX+LAP-M micelles with spherical morphology had a size of ~112 nm and had an initial negative surface charge, which are favorable characteristics for long-term circulation in the blood. Once the micelles accumulated in tumor tissues, the intrinsic tumor extracellular acidity triggered the charge switch of DOX+LAP-M micelles from -1 to 9 mV, thereby facilitating cell internalization and tumor penetration. Subsequently, the pH-sensitive micellar core accelerated the release of doxorubicin and lapatinib in the acidic intracellular environment. DOX+LAP-M micelles effectively inhibited the proliferation, migration, and invasion of 4T1 cells in vitro; furthermore, the administration of DOX+LAP-M micelles in 4T1 xenograft-bearing mice suppressed solid tumor growth with an inhibitory rate of 90.2% and significantly decreased pulmonary metastatic nodules, without significant systemic toxicity. This multifunctional micellar system has high potential for clinical cancer therapy.


Assuntos
Neoplasias da Mama , Micelas , Animais , Neoplasias da Mama/tratamento farmacológico , Doxorrubicina/farmacologia , Humanos , Concentração de Íons de Hidrogênio , Lapatinib , Camundongos , Cimento de Policarboxilato
18.
J Control Release ; 326: 350-364, 2020 10 10.
Artigo em Inglês | MEDLINE | ID: mdl-32707209

RESUMO

Stimuli-responsive nanotechnology-mediated drug co-delivery system is a notable strategy to improve access of the systemically administered chemotherapeutics to the tumors. Herein, a tailor-made 2,3-dimethylmaleic-anhydride-poly(ethylene glycol)-ε-poly-l-lysine-doxorubicin /lapatinib polymeric nanoplatform (DMMA-P-DOX/LAP) for synergistically eliminating breast cancer is developed by encapsulating lapatinib into dual-pH responsive charge switchable biopolymer-doxorubicin conjugate nanoparticles. The physicochemical properties of polymeric nanoparticles are conducive to their stable circulation in the physiological condition, but reverse the surface charge from negative to positive ultrasensitively in slightly acidic tumor microenvironment, facilitating cell internalization and deep tumor penetration. Subsequently, DOX and LAP are synchronously released into the cytoplasm in response to the significantly increased acidity of intracellular environment. As a result, the combination therapy by DMMA-P-DOX/LAP nanoparticles compels the solid tumors to contract significantly or even vanish completely in the MCF-7 tumor model, moreover, the structural composition with amino acid and bioinert PEG ensures the favorable biosecurity of the co-delivery system in vivo. This dual-pH responsive nanotechnology-mediated drug co-delivery system provides great potentials for safe and effective cancer therapy.


Assuntos
Neoplasias da Mama , Nanopartículas , Neoplasias da Mama/tratamento farmacológico , Doxorrubicina/uso terapêutico , Portadores de Fármacos/uso terapêutico , Sistemas de Liberação de Medicamentos , Feminino , Humanos , Concentração de Íons de Hidrogênio , Polietilenoglicóis/uso terapêutico , Polilisina , Microambiente Tumoral
19.
Adv Mater ; 32(31): e2000038, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32596808

RESUMO

Fenton reaction-mediated oncotherapy is an emerging strategy which uses iron ions to catalytically convert endogenous hydrogen peroxide into hydroxyl radicals, the most reactive oxygen species found in biology, for efficient cancer therapy. However, Fenton reaction efficiency in tumor tissue is typically limited due to restrictive conditions. One strategy to overcome this obstacle is to increase the temperature specifically at the tumor site. Herein, a tumor-targeting iron sponge (TTIS) nanocomposite based on graphdiyne oxide, which has a high affinity for iron is described. TTIS can accumulate in tumor tissue by decoration with a tumor-targeting polymer to enable tumor photoacoustic and magnetic resonance imaging. With its excellent photothermal conversion efficiency (37.5%), TTIS is an efficient photothermal therapy (PTT) agent. Moreover, the heat produced in the process of PTT can accelerate the release of iron ions from TTIS and simultaneously enhance the efficiency of the Fenton reaction, thus achieving a combined PTT and Fenton reaction-mediated cancer therapy. This work introduces a graphdiyne oxide-based iron sponge that exerts an enhanced antitumor effect through PTT and Fenton chemistry.


Assuntos
Grafite/química , Peróxido de Hidrogênio/química , Ferro/química , Nanocompostos/química , Animais , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Feminino , Óxido Ferroso-Férrico/química , Hemólise/efeitos dos fármacos , Humanos , Peróxido de Hidrogênio/farmacologia , Hipertermia Induzida , Camundongos , Camundongos Endogâmicos BALB C , Nanocompostos/toxicidade , Neoplasias/diagnóstico por imagem , Neoplasias/patologia , Neoplasias/terapia , Fototerapia , Espécies Reativas de Oxigênio/metabolismo , Nanomedicina Teranóstica , Ensaios Antitumorais Modelo de Xenoenxerto
20.
Water Sci Technol ; 81(4): 790-800, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32460282

RESUMO

In recent years, industrial contaminants and especially organic pollutions have been threatening both environmental safety and human health. Particularly, dibutyl phthalate (DBP) has been considered as one of the major hazardous contaminants due to its widespread production and ecological toxicities. Consequently, reliable methods toward the efficient and environmentally benign degradation of DBP in wastewater would be very desirable. To this end, a novel magnetically separable porous TiO2/Ag composite photocatalyst with magnetic Fe3O4 particles as the core was developed and successfully introduced to the photocatalytic degradation of DBP under visible irradiation with a fluorescent lamp. The presented work describes the grafting of Ag co-doped TiO2 composite on the silica-modified porous Fe3O4 magnetic particles with a simple and inexpensive chemical co-precipitation method. Through the investigation of the influencing factors including photocatalyst dosage, initial concentration of DBP, solution pH, and H2O2 content, we found that the degradation efficiency could reach 74%. The photodegradation recovery experiment showed that the degradation efficiency of this photocatalyst remained almost the same after five times of reuse. In addition, a plausible degradation process was also proposed involving the attack of active hydroxyl radicals generated from this photocatalysis system and production of the corresponding intermediates of butyl phthalate, diethyl phthalate, dipropyl phthalate, methyl benzoate, and benzoic acid.


Assuntos
Dibutilftalato , Dióxido de Silício , Catálise , Peróxido de Hidrogênio , Fotólise , Prata , Titânio
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