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1.
Int J Mol Sci ; 25(4)2024 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-38396747

RESUMO

Nanoencapsulation has become a recent advancement in drug delivery, enhancing stability, bioavailability, and enabling controlled, targeted substance delivery to specific cells or tissues. However, traditional nanoparticle delivery faces challenges such as a short circulation time and immune recognition. To tackle these issues, cell membrane-coated nanoparticles have been suggested as a practical alternative. The production process involves three main stages: cell lysis and membrane fragmentation, membrane isolation, and nanoparticle coating. Cell membranes are typically fragmented using hypotonic lysis with homogenization or sonication. Subsequent membrane fragments are isolated through multiple centrifugation steps. Coating nanoparticles can be achieved through extrusion, sonication, or a combination of both methods. Notably, this analysis reveals the absence of a universally applicable method for nanoparticle coating, as the three stages differ significantly in their procedures. This review explores current developments and approaches to cell membrane-coated nanoparticles, highlighting their potential as an effective alternative for targeted drug delivery and various therapeutic applications.


Assuntos
Nanopartículas , Medicina de Precisão , Membrana Celular/metabolismo , Sistemas de Liberação de Medicamentos
2.
Neuropsychology ; 38(4): 357-367, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38330358

RESUMO

OBJECTIVE: The processing speed (PS) is highly impacted in individuals experiencing their first episode of psychosis (FEP). Conducting family studies can help to determine whether PS can serve as an endophenotype of schizophrenia spectrum disorders (SSDs), offering valuable insights into the prevention and diagnosis of SSDs. METHOD: A comprehensive cognitive battery, encompassing tests for PS, verbal memory, visual memory, working memory, executive functions, motor dexterity, and attention, was administered to a sample consisting of 133 FEP patients, 146 parents, 98 siblings, and 202 healthy controls (HCs). Univariate analyses (analysis of covariance [ANCOVA]) were conducted to compare the different cognitive domains between groups, utilizing sex, age, and years of education as covariates and Bonferroni corrections. Effect sizes (ESs) were calculated for estimating the magnitude of differences between groups. RESULTS: Group comparisons revealed significant differences in all cognitive domains. PS was the most impaired function in patients. Parents and siblings had intermediate PS performance between FEP patients and HC. Large ES were observed in PS between FEP versus siblings, FEP versus controls, parents versus controls, and parents versus siblings. CONCLUSIONS: Despite not meeting all the necessary criteria, the PS observed in FEP patients and their first-degree relatives suggests its potential as a promising endophenotype of SSDs. (PsycInfo Database Record (c) 2024 APA, all rights reserved).


Assuntos
Endofenótipos , Testes Neuropsicológicos , Transtornos Psicóticos , Esquizofrenia , Humanos , Masculino , Feminino , Adulto , Transtornos Psicóticos/fisiopatologia , Esquizofrenia/fisiopatologia , Esquizofrenia/complicações , Adulto Jovem , Irmãos , Pessoa de Meia-Idade , Família , Pais/psicologia , Função Executiva/fisiologia , Psicologia do Esquizofrênico , Adolescente , Velocidade de Processamento
3.
ACS Chem Neurosci ; 14(15): 2811-2817, 2023 08 02.
Artigo em Inglês | MEDLINE | ID: mdl-37471620

RESUMO

As the population ages, an epidemic of neurodegenerative diseases with devastating social consequences is looming. To address the pathologies leading to amyloid-related dementia, novel therapeutic strategies must be developed for the treatment or prevention of neural protein-folding disorders. Nanotechnology will be crucial to this scenario, especially in the design of nanoscale systems carrying therapeutic compounds that can navigate the nervous system and identify amyloid to treat it in situ. In this line, we have recently designed a highly simplified and versatile nanorobot consisting of a protein coating based on the heat shock protein 90 (Hsp90) chaperone that not only propels nanoparticles using ATP but also endows them with the extraordinary ability to fold and restore the activity of heat-denatured proteins. Here, we assess the effectiveness of these nanosystems in inhibiting/reducing the aggregation of amyloidogenic proteins. Using Raman spectroscopy, we qualitatively and quantitatively analyze amyloid by identifying and semi-quantifying the Amide I band. Our findings indicate that the coupling of Hsp90 to nanoparticles results in a more potent inhibition of amyloid formation when compared to the soluble protein. We propose that this enhanced performance may be attributed to enhanced release-capture cycles of amyloid precursor oligomers by Hsp90 molecules nearby on the nanosurface. Intelligent biocompatible coatings, like the one described here, that enhance the diffusivity and self-propulsion of nanoparticles while enabling them to carry out critical functions such as environmental scanning, identification, and amyloid prevention, present an exceptional opportunity for the development of advanced nanodevices in biomedical applications. This approach, which combined active biomolecules with synthetic materials, is poised to reveal remarkable prospects in the field of nanomedicine and biotechnology.


Assuntos
Proteínas de Choque Térmico HSP90 , Nanopartículas , Chaperonas Moleculares/metabolismo , Amiloide/metabolismo , Proteínas Amiloidogênicas
4.
Int J Mol Sci ; 24(13)2023 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-37446406

RESUMO

Conventional targeted therapies for the treatment of cancer have limitations, including the development of acquired resistance. However, novel alternatives have emerged in the form of targeted therapies based on AB toxins. These biotoxins are a diverse group of highly poisonous molecules that show a nanomolar affinity for their target cell receptors, making them an invaluable source of ligands for biomedical applications. Bacterial AB toxins, in particular, are modular proteins that can be genetically engineered to develop high-affinity therapeutic compounds. These toxins consist of two distinct domains: a catalytically active domain and an innocuous domain that acts as a ligand, directing the catalytic domain to the target cells. Interestingly, many tumor cells show receptors on the surface that are recognized by AB toxins, making these high-affinity proteins promising tools for developing new methods for targeting anticancer therapies. Here we describe the structure and mechanisms of action of Diphtheria (Dtx), Anthrax (Atx), Shiga (Stx), and Cholera (Ctx) toxins, and review the potential uses of AB toxins in cancer therapy. We also discuss the main advances in this field, some successful results, and, finally, the possible development of innovative and precise applications in oncology based on engineered recombinant AB toxins.


Assuntos
Toxinas Bacterianas , Neoplasias , Humanos , Ligantes , Toxinas Bacterianas/metabolismo , Neoplasias/tratamento farmacológico , Receptores de Superfície Celular
5.
J Colloid Interface Sci ; 629(Pt A): 287-296, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36081208

RESUMO

Elongated nanostructures to be remotely and magnetically propelled in biologically relevant media, have gained attention as offering themselves as effective tools or carriers in theragnostics applications. However, the magnetic actuation associated remains challenging due to the lack of mechanical information in the media of interest, taking into account biophysical or biomedical purposes. In this study, we detail the magnetic actuation of magnetically propelled chained nanocomposites considering their dynamics, in which their velocity can be modulated in terms of the viscosity of the medium considered, given a magnetic field gradient. Simpler cases of distilled water, a water/glycerol mixture and a fluid made of cell extracts (imitating the cytosol of cells) of known viscosity are the basis experiments for the study of more complex media inside HeLa cells, murine NIH-3T3 fibroblasts and zebrafish larvae, offering the mechanical information required. The experimental results indicate that the magnetically propelled performance of the chained nanostructures can be precisely controlled in potentially changing scenarios, where drug and heat delivery, magnetic separation, or microfluidic technologies are demanded, using a magnetic field gradient and providing good estimations of the dynamical parameters involved.


Assuntos
Glicerol , Nanocompostos , Humanos , Camundongos , Animais , Células HeLa , Extratos Celulares , Peixe-Zebra , Água
6.
Pharmaceutics ; 16(1)2023 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-38258053

RESUMO

Leishmaniasis, a zoonotic parasitic disease transmitted by infected sandflies, impacts nearly 1 million people yearly and is endemic in many countries across Asia, Africa, the Americas, and the Mediterranean; despite this, it remains a neglected disease with limited effective treatments, particularly in impoverished communities with limited access to healthcare. This study aims to repurpose approved drugs for an affordable leishmaniasis treatment. After the screening of potential drug candidates by reviewing databases and utilizing molecular docking analysis, delamanid was chosen to be incorporated into solid lipid nanoparticles (SLNPs). Both in cellulo and in vivo tests confirmed the successful payload release within macrophages and through the epidermis following topical application on murine skin. The evaluation of macrophages infected with L. infantum amastigotes showed that the encapsulated delamanid exhibited greater leishmanicidal activity compared with the free drug. The process of encapsulating delamanid in SLNPs, as demonstrated in this study, places a strong emphasis on employing minimal technology, ensuring energy efficiency, cost-effectiveness, and reproducibility. It enables consistent, low-cost production of nanomedicines, even on a small scale, offering a promising step toward more accessible and effective leishmaniasis treatments.

7.
Int J Nanomedicine ; 17: 5747-5760, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36466783

RESUMO

Introduction: A great challenge in nanomedicine, and more specifically in theranostics, is to improve the specificity, selectivity, and targeting of nanomaterials towards target tissues or cells. The topical use of nanomedicines as adjuvants to systemic chemotherapy can significantly improve the survival of patients affected by localized carcinomas, reducing the side effects of traditional drugs and preventing local recurrences. Methods: Here, we have used the Shiga toxin, to design a safe, high-affinity protein-ligand (ShTxB) to bind the globotriaosylceramide receptor (GB3) that is overexpressed on the surfaces of preneoplastic and malignant cancer cells in the head and neck tumors. Results: We find that ShTxB functionalized gold nanorods are efficiently retrotranslocated to the GB3-positive cell cytoplasms. After 3 minutes of laser radiation with a wavelength resonant with the AuNR longitudinal localized surface plasmon, the death of the targeted cancer cells is activated. Both preclinical murine models and patient biopsy cells show the non-cytotoxic nature of these functionalized nanoparticles before light activation and their treatment selectivity. Discussion: These results show how the use of nanomedicines directed by natural ligands can represent an effective treatment for aggressive localized cancers, such as squamous cell carcinoma of the oral cavity.


Assuntos
Carcinoma de Células Escamosas , Neoplasias Bucais , Nanotubos , Humanos , Animais , Camundongos , Ouro , Toxina Shiga , Neoplasias Bucais/tratamento farmacológico
8.
Biomedicines ; 10(4)2022 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-35453483

RESUMO

Head and neck squamous cell carcinoma is the sixth leading cancer in the world. This cancer is difficult to treat and is characterized by recurrences that are often fatal. This cancer is generally removed surgically, but it often regrows from the edges of the lesion from where most recurrences reappear. In this study, we have investigated if the expression of GB3 in human cell lines, tissues from patient biopsies, and a murine animal model could be used as an early and determinant marker of HNC. We found that in all the investigated systems, this marker appears in neoplastic cells from the very early stages of their malignant transformation. Our conclusions support the hypothesis that GB3 is a reliable and independent target for HNC identification and selective delivery of treatments. Furthermore, we show that the level of expression of this marker correlates with the degree of malignancy of the tumor. These studies suggest that GB3 may provide the basis for the early identification and new targeted therapies for head and neck cancer.

9.
Bioact Mater ; 8: 153-164, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34541393

RESUMO

Nowadays, a number of promising strategies are being developed that aim at combining diagnostic and therapeutic capabilities into clinically effective formulations. Thus, the combination of a modified release provided by an organic encapsulation and the intrinsic physico-chemical properties from an inorganic counterpart opens new perspectives in biomedical applications. Herein, a biocompatible magnetic lipid nanocomposite vehicle was developed through an efficient, green and simple method to simultaneously incorporate magnetic nanoparticles and an anticancer drug (doxorubicin) into a natural nano-matrix. The theranostic performance of the final magnetic formulation was validated in vitro and in vivo, in melanoma tumors. The systemic administration of the proposed magnetic hybrid nanocomposite carrier enhanced anti-tumoral activity through a synergistic combination of magnetic hyperthermia effects and antimitotic therapy, together with MRI reporting capability. The application of an alternating magnetic field was found to play a dual role, (i) acting as an extra layer of control (remote, on-demand) over the chemotherapy release and (ii) inducing a local thermal ablation of tumor cells. This combination of chemotherapy with thermotherapy establishes a synergistic platform for the treatment of solid malignant tumors under lower drug dosing schemes, which may realize the dual goal of reduced systemic toxicity and enhanced anti-tumoral efficacy.

10.
Cancers (Basel) ; 13(19)2021 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-34638405

RESUMO

Head and Neck Cancer (HNC) is the seventh most common cancer worldwide with a 5-year survival from diagnosis of 50%. Currently, HNC is diagnosed by a physical examination followed by an histological biopsy, with surgery being the primary treatment. Here, we propose the use of targeted nanotechnology in support of existing diagnostic and therapeutic tools to prevent recurrences of tumors with poorly defined or surgically inaccessible margins. We have designed an innocuous ligand-protein, based on the receptor-binding domain of the Shiga toxin (ShTxB), that specifically drives nanoparticles to HNC cells bearing the globotriaosylceramide receptor on their surfaces. Microscopy images show how, upon binding to the receptor, the ShTxB-coated nanoparticles cause the clustering of the globotriaosylceramide receptors, the protrusion of filopodia, and rippling of the membrane, ultimately allowing the penetration of the ShTxB nanoparticles directly into the cell cytoplasm, thus triggering a biomimetic cellular response indistinguishable from that triggered by the full-length Shiga toxin. This functionalization strategy is a clear example of how some toxin fragments can be used as natural biosensors for the detection of some localized cancers and to target nanomedicines to HNC lesions.

11.
J Nanobiotechnology ; 19(1): 129, 2021 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-33952241

RESUMO

BACKGROUND: The intrinsic physicochemical properties of carbon nanotubes (CNTs) make them unique tools in nanotechnology. Their elemental composition, resilience, thermal properties, and surface reactivity make CNTs also of undisputed interest in biotechnology. In particular, their extraordinary ability to capture biomolecules on their surface makes them essential in this field. The proteins adsorbed on the CNTs create a biological coating that endows them the ability to interact with some cell receptors, penetrate membranes or interfere with cell biomechanics, thus behaving as an active bio-camouflage. But some of these proteins unfold, triggering an immune response that unpredictably changes the biological activity of CNTs. For this reason, the control of the biocorona is fundamental in the nanobiotechnology of CNTs. RESULTS: Using TEM and AFM here we demonstrate a significant increase in CNTs diameter after protein functionalization. A quantitative analysis using TGA revealed that between 20 and 60% of the mass of functionalized nanotubes corresponds to protein, with single-walled CNTs capturing the highest amounts. To qualitatively/quantitatively characterize these biocoatings, we studied the biochemical "landscape" of the proteins captured by the different nanotubes after functionalization under various conditions. This study revealed a significant variability of the proteins in the corona as a function of the type of nanotube, the functionalization temperature, or the time after exposure to serum. Remarkably, the functionalization of a single type of CNT with sera from various human donors also resulted in different protein landscapes. Given the unpredictable assortment of proteins captured by the corona and the biological implications of this biocoating, we finally designed a method to genetically engineer and produce proteins to functionalize nanotubes in a controlled and customizable way. CONCLUSIONS: We demonstrate the high unpredictability of the spontaneous protein corona on CNTs and propose a versatile functionalization technique that prevents the binding of nonspecific proteins to the nanotube to improve the use of CNTs in biomedical applications.


Assuntos
Incrustação Biológica/prevenção & controle , Proteínas Sanguíneas , Nanotecnologia/métodos , Nanotubos de Carbono/química , Adsorção , Proteínas Sanguíneas/genética , Proteínas Sanguíneas/metabolismo , Humanos , Coroa de Proteína , Soro/química
12.
Int J Mol Sci ; 21(24)2020 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-33339139

RESUMO

There are many nanoencapsulation systems available today. Among all these, mesoporous silica particles (MSPs) have received great attention in the last few years. Their large surface-to-volume ratio, biocompatibility, and versatility allow the encapsulation of a wide variety of drugs inside their pores. However, their chemical instability in biological fluids is a handicap to program the precise release of the therapeutic compounds. Taking advantage of the dissolving capacity of silica, in this study, we generate hollow capsules using MSPs as transitory sacrificial templates. We show how, upon MSP coating with different polyelectrolytes or proteins, fully customized hollow shells can be produced. These capsules are biocompatible, flexible, and biodegradable, and can be decorated with nanoparticles or carbon nanotubes to endow the systems with supplementary intrinsic properties. We also fill the capsules with a fluorescent dye to demonstrate intracellular compound release. Finally, we document how fluorescent polymeric capsules are engulfed by cells, releasing their encapsulated agent during the first 96 h. In summary, here, we describe how to assemble a highly versatile encapsulation structure based on silica mesoporous cores that are completely removed from the final polymeric capsule system. These drug encapsulation systems are highly customizable and have great versatility as they can be made using silica cores of different sizes and multiple coatings. This provides capsules with unique programmable attributes that are fully customizable according to the specific needs of each disease or target tissue for the development of nanocarriers in personalized medicine.


Assuntos
Nanocápsulas/química , Dióxido de Silício/química , Liberação Controlada de Fármacos , Corantes Fluorescentes/administração & dosagem , Células HeLa , Humanos , Polieletrólitos/química
13.
J Nanobiotechnology ; 18(1): 181, 2020 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-33317574

RESUMO

Microtubules and carbon nanotubes (CNTs), and more particularly multi-walled CNTs (MWCNTs), share many mechanical and morphological similarities that prompt their association into biosynthetic tubulin filaments both, in vitro and in vivo. Unlike CNTs, microtubules are highly dynamic protein polymers that, upon interaction with these nanomaterials, display enhanced stability that has critical consequences at the cellular level. Among others, CNTs prompt ectopic (acentrosomal) microtubule nucleation and the disassembly of the centrosome, causing a dramatic cytoskeletal reorganization. These changes in the microtubule pattern trigger the generation of ineffective biomechanical forces that result in migration defects, and ultimately in spindle-assembly checkpoint (SAC) blockage and apoptosis. In this review, we describe the molecular mechanism involved in the intrinsic interference of CNTs with the microtubule dynamics and illustrate the consequences of this effect on cell biomechanics. We also discuss the potential application of these synthetic microtubule-stabilizing agents as synergetic agents to boost the effect of classical chemotherapy that includes spindle poisons (i.e. paclitaxel) or DNA interfering agents (5-fluorouracil)-, and list some of the advantages of the use of MWCNTs as adjuvant agents in preventing cell resistance to chemotherapy.


Assuntos
Citoesqueleto/efeitos dos fármacos , Citoesqueleto/metabolismo , Microtúbulos/efeitos dos fármacos , Microtúbulos/metabolismo , Neoplasias/tratamento farmacológico , Apoptose , Ciclo Celular/efeitos dos fármacos , Centrossomo/metabolismo , Citoesqueleto/ultraestrutura , Humanos , Microtúbulos/ultraestrutura , Nanotubos de Carbono , Paclitaxel/farmacologia , Fenótipo , Tubulina (Proteína)
14.
Anal Methods ; 12(46): 5642-5647, 2020 12 07.
Artigo em Inglês | MEDLINE | ID: mdl-33185213

RESUMO

Understanding the biological effects triggered by nanomaterials is crucial, not only in nanomedicine but also in toxicology. The dose-response relation is relevant in biological tests due to its use for determining appropriate dosages for drugs and toxicity limits. Carbon nanotubes can trigger numerous unusual biological effects, many of which could have unique applications in biotechnology and medicine. However, their resuspension in saline solutions and the accurate determination of their concentration after dispersion in biological media are major handicaps to identify the magnitude of the response of organisms as a function of this exposure. This difficulty has led to inconsistent results and misinterpretations of their in vivo behavior, limiting their potential use in nanomedicine. The lack of a suitable protocol that allows comparing different studies of the content of carbon nanotubes and their adequate resuspension in culture cell media gives rise to this study. Here, we describe a methodology to functionalize, resuspend and determine the carbon nanotube concentration in biocompatible media based on UV-Vis spectroscopy. This method allows us to accurately estimate the concentration of these resuspended carbon nanotubes, after removing bundles and micrometric aggregates, which can be used as a calibration standard, for dosage-dependent studies in biological systems. This method can also be extended to any other nanomaterial to properly quantify the actual concentration.


Assuntos
Nanoestruturas , Nanotubos de Carbono , Nanomedicina , Nanotubos de Carbono/toxicidade
15.
Nanomedicine ; 29: 102268, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32663511

RESUMO

Here we propose a one-step strategy to endow nanomaterials with a custom-designed bio-identity. This study designs a universal 'nanomaterial binding domain' that can be genetically attached to any protein ensuring precise and spontaneous protein orientation. We demonstrate how, despite the simplicity of the method, the bioconjugation achieved: (i) is highly efficient, even in the presence of competing proteins, (ii) is stable at extreme physiological conditions (pH ranges 5.2-9.0; NaCl concentrations 0-1 M); (iii) prevents unwanted protein biofouling days after incubation in biologically-relevant conditions; and finally, (iv) avoids nanoparticle interaction with promiscuous unspecific receptors. In summary, this protein biocoating technique, applicable to a wide array of nano-designs, integrates material science and molecular biology procedures to create hybrid nanodevices with well-defined surfaces and predictable biological behaviors, opening a chapter in precision nanodiagnostics, nanosensing or nanotherapeutic applications.


Assuntos
Sistemas de Liberação de Medicamentos , Nanomedicina/tendências , Nanopartículas/química , Nanoestruturas/química , Humanos , Nanopartículas/análise , Nanopartículas/uso terapêutico , Nanoestruturas/análise , Nanoestruturas/uso terapêutico , Ligação Proteica/efeitos dos fármacos , Domínios Proteicos/efeitos dos fármacos , Proteínas/química
16.
Pharmaceutics ; 12(6)2020 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-32481488

RESUMO

Mesoporous silica particles (MSP) are major candidates for drug delivery systems due to their versatile, safe, and controllable nature. Understanding their intracellular route and biodegradation process is a challenge, especially when considering their use in neuronal repair. Here, we characterize the spatiotemporal intracellular destination and degradation pathways of MSP upon endocytosis by HeLa cells and NSC-34 motor neurons using confocal and electron microscopy imaging together with inductively-coupled plasma optical emission spectroscopy analysis. We demonstrate how MSP are captured by receptor-mediated endocytosis and are temporarily stored in endo-lysosomes before being finally exocytosed. We also illustrate how particles are often re-endocytosed after undergoing surface erosion extracellularly. On the other hand, silica particles engineered to target the cytosol with a carbon nanotube coating, are safely dissolved intracellularly in a time scale of hours. These studies provide fundamental clues for programming the sub-cellular fate of MSP and reveal critical aspects to improve delivery strategies and to favor MSP safe elimination. We also demonstrate how the cytosol is significantly more corrosive than lysosomes for MSP and show how their biodegradation is fully biocompatible, thus, validating their use as nanocarriers for nervous system cells, including motor neurons.

17.
Nanoscale ; 12(10): 6164-6175, 2020 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-32133463

RESUMO

In vivo imaging and therapy represent one of the most promising areas in nanomedicine. Particularly, the identification and localization of nanomaterials within cells and tissues are key issues to understand their interaction with biological components, namely their cell internalization route, intracellular destination, therapeutic activity and possible cytotoxicity. Here, we show the development of multifunctional nanoparticles (NPs) by providing luminescent functionality to zinc and iron oxide NPs. We describe simple synthesis methods based on modified Stöber procedures to incorporate fluorescent molecules on the surface of oxide NPs. These procedures involve the successful coating of NPs with size-controlled amorphous silica (SiO2) shells incorporating standard chromophores like fluorescein, rhodamine B or rhodamine B isothiocyanate. Specifically, spherical Fe3O4 NPs with an average size of 10 nm and commercial ZnO NPs (ca. 130 nm), both coated with an amorphous SiO2 shell of ca. 15 and 24 nm thickness, respectively, are presented. The magnetic nanoparticles, with a major presence of magnetite, show negligible coercitivity. Hence, interactions (dipolar) are very weak and the cores are in the superparamagnetic regime. Spectroscopic measurements confirm the presence of fluorescent molecules within the SiO2 shell, making these hybrid NPs suitable for bioimaging. Thus, our coating procedures improve NP dispersibility in physiological media and allow the identification and localization of intracellular ZnO and Fe3O4 NPs using confocal microscopy imaging preserving the fluorescence of the NP. We demonstrate how both Fe3O4 and ZnO NPs coated with luminescent SiO2 are internalized and accumulated in the cell cytoplasm after 24 hours. Besides, the SiO2 shell provides a platform for further functionalization that enables the design of targeted therapeutic strategies. Finally, we studied the degradation of the shell in different physiological environments, pointing out that the SiO2 coating is stable enough to reach the target cells maintaining its original structure. Degradation took place only 24 hours after exposure to different media.


Assuntos
Materiais Revestidos Biocompatíveis , Compostos Férricos , Corantes Fluorescentes , Teste de Materiais , Nanopartículas/química , Dióxido de Silício , Materiais Revestidos Biocompatíveis/química , Materiais Revestidos Biocompatíveis/farmacologia , Compostos Férricos/química , Compostos Férricos/farmacologia , Corantes Fluorescentes/química , Corantes Fluorescentes/farmacologia , Células HeLa , Humanos , Microscopia de Fluorescência , Dióxido de Silício/química , Dióxido de Silício/farmacologia , Óxido de Zinco/química , Óxido de Zinco/farmacologia
18.
Int J Nanomedicine ; 14: 3389-3401, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31190798

RESUMO

The implementation of nanotechnology in medicine has opened new research horizons particularly in the field of therapeutic delivery. Mesoporous silica particles have emerged as biocompatible drug delivery systems with an enormous potential in the treatment of cancer among many other pathologies. In this review, we focus on the unique properties of these particles as chemotherapy delivery carriers. Here, we summarize the general characteristics of these nanomaterials - including their physicochemical properties and customizable surfaces - different stimuli that can be used to trigger targeted drug release, biocompatibility and finally, the drawbacks of these types of nanomaterials, highlighting some of the most important features of mesoporous silica nanoparticles in drug delivery.


Assuntos
Preparações de Ação Retardada/uso terapêutico , Sistemas de Liberação de Medicamentos , Nanopartículas/química , Neoplasias/tratamento farmacológico , Dióxido de Silício/química , Humanos , Porosidade
19.
Oncotarget ; 10(21): 2022-2029, 2019 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-31007845

RESUMO

Multiple-drug resistance in human cancer is a major problem. To circumvent this issue, clinicians combine several drugs. However, this strategy could backfire resulting in more toxic or ineffective treatments. Carbon nanotubes (CNTs), and particularly multi-walled nanotubes (MWCNTs), display intrinsic properties against cancer interfering with microtubule dynamics and triggering anti-proliferative, anti-migratory and cytotoxic effects in vitro that result in tumor growth inhibition in vivo. Remarkably, these effects are maintained in tumors resistant to traditional microtubule-binding chemotherapies such as Taxol®. In the view of these properties, we investigate the use of MWCNTs in the development of active-by-design nanocarriers, attempting to enhance the effect of broadly-used chemotherapies. We compare the cytotoxic and the anti-tumoral effect of 5-Fluorouracil (5-FU) -an antimetabolite treatment of various forms of cancer- with that of the drug physisorbed onto MWCNTs. Our results demonstrate how the total effect of the drug 5-FU is remarkably improved (50% more effective) when delivered intratumorally coupled to MWCNTs both in vitro and in vivo in solid tumoral models. Our results demonstrate how using MWCNTs as anti-cancer drug delivery platforms is a promising approach to boost the efficacy of traditional chemotherapies, while considerably reducing the chances of resistance in cancer cells.

20.
Angew Chem Int Ed Engl ; 56(44): 13736-13740, 2017 10 23.
Artigo em Inglês | MEDLINE | ID: mdl-28873280

RESUMO

The translocation of nanomaterials or complex delivery systems into the cytosol is a major challenge in nanobiotechnology. After receptor-mediated endocytosis, most nanomaterials are sequestered and undergo degradation, therapy inactivation, or exocytosis. Herein we explore a novel surface particle coating made of adsorbed carbon nanotubes that provides coated materials with new properties that reproduce the viral cell-invasive mechanisms, namely, receptor-mediated endocytosis, endolysosomal escape, and cytosolic particle release preserving cell viability. This novel biomimetic coating design will enable the intracytoplasmic delivery of many different functional materials endowed with therapeutic, magnetic, optical, or catalytic functionalities, thus opening the door to a wide array of chemical and physical processes within the cytosolic or nuclear domains, and supporting new developments in the biotechnological, pharmaceutical, and biomedical industries.


Assuntos
Materiais Biomiméticos/metabolismo , Materiais Revestidos Biocompatíveis/metabolismo , Citoplasma/metabolismo , Endocitose , Nanopartículas/metabolismo , Dióxido de Silício/metabolismo , Materiais Biomiméticos/química , Biomimética , Sobrevivência Celular , Materiais Revestidos Biocompatíveis/química , Células HeLa , Humanos , Nanopartículas/química , Nanotubos de Carbono/química , Dióxido de Silício/química , Propriedades de Superfície
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