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1.
Chem Commun (Camb) ; 57(93): 12417-12435, 2021 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-34734601

RESUMO

Covalent organic frameworks (COFs), as a new type of crystalline porous materials, mainly consist of light-weight elements (H, B, C, N and O) linked by dynamic covalent bonds to form periodical structures of two or three dimensions. As an attribute of their low density, large surface area, and excellent adjustable pore size, COFs show great potential in many fields including energy storage and separation, catalysis, sensing, and biomedicine. However, compared with metal organic frameworks (MOFs), the relatively large size and irregular morphology of COFs affect their biocompatibility and bioavailability in vivo, thus impeding their further biomedical applications. This Review focuses on the controlled design strategies of nanoscale COFs (NCOFs), unique properties of NCOFs for biomedical applications, and recent progress in NCOFs for cancer therapy. In addition, current challenges for the biomedical use of NCOFs and perspectives for further improvements are presented.

2.
Transl Oncol ; 15(1): 101264, 2021 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-34781185

RESUMO

Magnetic nanoparticles (MNPs) have been extensively researched and implemented in biomedicine for more than half a century due to their non-invasive nature, ease of temporal and spatial manipulation, and considerable biocompatibility. However, the complex magnetic behaviour of MNPs is influenced by several parameters (e.g., particle size, shape, composition, core-shell structure, etc.), among which the amount of transition metal doping plays an important factor. For this reason, the doping of ferrite with transition metals has been used as an effective strategy to precisely tailor MNPs to achieve satisfactory performance in biomedical applications. In this review, we first introduced the main properties of coordinated MNPs (including magnetic moment and saturated magnetisation) and provide a comprehensive overview of the mechanistic studies related to the doping of transition metal ions into ferrite to precisely modulate its magnetic properties. We also highlighted the potential mechanisms and recent advances in transition metal ion-doped MNPs (TMNPs) for bioimaging (magnetic resonance imaging and magnetic particle imaging) and tumour therapy (e.g., magneto-mechanical killing, magnetothermal therapy, and drug delivery). Finally, we summarised the current challenges and future trends of TMNPs in the biomedical field based on the latest advances by researchers.

3.
J Phys Chem Lett ; 12(46): 11280-11287, 2021 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-34767373

RESUMO

Zeolitic imidazolate frameworks (ZIFs), widely regarded as promising materials for application in catalysis and separation, hold an increasingly significant position in drug delivery systems for their high drug loading capacity. Focused specifically on the rational design of targeting and bioresponsive nanovehicles, a neuropeptide Y1 receptor ligand (Y1L)-modified cell membrane camouflaged bioresponsive ZIF system (Y1L-RBC@ZIF-90@Ce6) was constructed for targeted photodynamic therapy of breast cancer. The biomimetic ZIF-based nanocarrier enhanced tumor accumulation by both neuropeptide Y1 receptor-targeted guidance and long-term stability. Y1L served as a good ligand-mediated selective targeting molecule for breast cancer, and red blood cell membrane-camouflaged nanocomposites displayed favorable biocompatibility. With the dual response of the ZIF to pH and adenosine triphosphate, the stimulus responsive photosensitizer Chlorin e6 delivery system effectively suppressed tumors in vivo. This work offers a platform for developing much safer and more efficient photodynamic therapy for the treatment of Y1R-overexpressed breast cancer.

4.
Environ Monit Assess ; 193(10): 623, 2021 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-34477949

RESUMO

The aim of the study was to assess the status of groundwater quality of Owerri and environs, for drinking and irrigation purposes. Twenty-two (22) groundwater samples were collected and analyzed for both chemical and physical compositions. The result of the study showed that groundwater in the area is of good quality for drinking purposes, except for pH and Fe, which had higher concentrations in some areas. A weak correlation matrix within the sampled parameters of the groundwater was observed. Hydrogeochemical studies revealed that 91% of the samples are within the geochemical zone of 4 (strong acids (SO4 + Cl) exceed weak acids (CO3 + HCO3)), while 9% are of the geochemical zone of 3 (weak acids (CO3 + HCO3) exceed strong acids (SO4 + Cl)). The study shows an ionic trend of Cl- > Ca2+ > HCO3- > Na+ + K+ > Mg2+ > SO42- and hydrogeochemical facies of Na-Cl, Ca-Cl, Ca-CO3, Mg-Cl, and Mg-HCO3 of 45.5%, 36.4%, 4.5%, 4.5%, and 9.1% respectively. Chloro-alkaline values were negative except for B4 which was positive. The water quality index (WQI) revealed water quality status of excellent (4.5%), good (27.3%), poor (40.9%), and very poor (27.3%). Contamination factor (CF) reveals that the groundwater is slightly polluted while the pollution load index (PLI) revealed no noticeable pollution. Gibbs diagram revealed that the entire samples are within the rock dominance zone. Irrigation suitability studies showed that SAR of the groundwater was of excellent quality; %Na had good quality (27.3%), permissible quality (45.4%), and doubtful quality (27.3%); MH had 86.4% of the groundwater suitable, while 13.6% are not suitable; KR had suitable groundwater (59.1%) and unsuitable (40.9%); while the Wilcox diagram had 72.7% excellent water for irrigation and 27.3% permissible for irrigation. A routine check of groundwater in the study area is recommended.


Assuntos
Água Subterrânea , Poluentes Químicos da Água , Monitoramento Ambiental , Facies , Humanos , Nigéria , Poluentes Químicos da Água/análise , Qualidade da Água
5.
Sci China Life Sci ; 2021 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-34258713

RESUMO

The detection of circulating tumor cells (CTCs) is a crucial tool for early cancer diagnosis, prognosis, and postoperative evaluation. However, detection sensitivity remains a major challenge because CTCs are extremely rare in peripheral blood. To effectively detect CTCs, octahedral Ag2O nanoparticles (NPs) with high dispersibility, good biocompatibility, remarkable surface-enhanced Raman scattering (SERS) enhancement, and obvious enhancement selectivity are designed as an SERS platform. Ag2O NPs with many oxygen vacancy defects are successfully synthesized, which exhibit an ultra-high SERS enhancement factor (1.98×106) for 4-mercaptopyridine molecules. The remarkable SERS activity of octahedral Ag2O NPs is derived from the synergistic effect of the surface defect-promoted photo-induced charge transfer (PICT) process and strong vibration coupling resonance in the Ag2O-molecule SERS complex, greatly amplifying the molecular Raman scattering cross-section. The promoted PICT process is confirmed using ultraviolet-visible (UV-Vis) absorption spectroscopy, demonstrating that obvious PICT resonance occurs in Ag2O SERS system under visible light. An additional growth step of SERS bioprobe is proposed by modifying the Raman signal molecules and functional biological molecules on Ag2O NPs for CTC detection. The Ag2O-based SERS bioprobe exhibits excellent detection specificity for different cancer cells in rabbit blood. Importantly, the high-sensitivity Ag2O-based SERS bioprobe satisfies the requirement for rare CTC detection in the peripheral blood of cancer patients, and the detection limit can reach 1 cell per mL. To our knowledge, this study is the first time that a semiconductor SERS substrate has been successfully utilized in CTC detection. This work provides new insights into CTC detection and the development of novel semiconductor-based SERS platforms for cancer diagnosis.

6.
J Environ Sci (China) ; 104: 351-364, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33985738

RESUMO

Cadmium contamination of soil is a global issue and in-situ remediation technology as a promising mitigation strategy has attracted more and more attention. Many nanomaterials have been applied for the in-situ remediation of cadmium-contaminated soil due to their excellent properties of the nano-scale size effect. In this work, recent research progress of various nanomaterials, including carbon nanomaterials, metal-based nanomaterials and nano mineral materials, in the removal of cadmium and in-situ remediation of cadmium-contaminated soil were systematically discussed. Additional emphases were particularly laid on both laboratory and field restoration effects. Moreover, the factors which can affect the stability of cadmium, main interaction mechanisms between nanomaterials and cadmium in the soil, and potential future research direction were also provided. Therefore, it is believed that this work will ultimately contribute to the myriad of environmental cleanup advances, and further improve human health and sustainable development.


Assuntos
Recuperação e Remediação Ambiental , Nanoestruturas , Poluentes do Solo , Cádmio/análise , Humanos , Solo , Poluentes do Solo/análise
7.
Nanoscale ; 13(13): 6461-6474, 2021 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-33885526

RESUMO

Unlike stable atherosclerotic plaques, vulnerable plaques are very likely to cause serious cardio-cerebrovascular diseases. Meanwhile, how to non-invasively identify vulnerable plaques at early stages has been an urgent but challenging problem in clinical practices. Here, we propose a macrophage-targeted and in situ stimuli-triggered T1-T2 switchable magnetic resonance imaging (MRI) nanoprobe for the non-invasive diagnosis of vulnerable plaques. Precisely, single-dispersed iron oxide nanoparticles (IONPs) modified with hyaluronic acid (HA), denoted as IONP-HP, show macrophage targetability and T1 MRI enhancement (r2/r1 = 3.415). Triggered by the low pH environment of macrophage lysosomes, the single-dispersed IONP-HP transforms into a cluster analogue, which exhibits T2 MRI enhancement (r2/r1 = 13.326). Furthermore, an in vivo switch of T1-T2 enhancement modes shows that the vulnerable plaques exhibit strong T1 enhancement after intravenous administration of the nanoprobe, followed by a switch to T2 enhancement after 9 h. In contrast, stable plaques show only slight T1 enhancement but without T2 enhancement. It is therefore imperative that the intelligent and novel nanoplatform proposed in this study achieves a substantial non-invasive diagnosis of vulnerable plaques by means of a facile but effective T1-T2 switchable process, which will significantly contribute to the application of materials science in solving clinical problems.


Assuntos
Meios de Contraste , Placa Aterosclerótica , Humanos , Imageamento por Ressonância Magnética , Placa Amiloide , Placa Aterosclerótica/diagnóstico por imagem
8.
Artigo em Inglês | MEDLINE | ID: mdl-33185008

RESUMO

Given the diversity, complexity, and heterogeneity of persistent tumors, traditional nanoscale monotherapeutic systems suffer from dissatisfactory curative efficiency with incidence of metastasis or relapse. In parallel, the trend of clinical research on the basis of nanomedicines has increasingly shifted from monotherapy toward combinatorial therapy for admirable synergetic performances. In this regard, cutting-edge nanomedicines harnessing photothermal-chemodynamic bimodal therapy (PTT/CDT) have opened up a highly-efficient and relatively-safe cancer theranostic paradigm. Still, the integration of PTT/CDT functional units into one nanomedicine remains a herculean but meaningful task to achieve notable super-additive effects. This review aims to elucidate underlying synergistic interactions of PTT/CDT and highlight intriguing designs of nanomedicines for PTT/CDT including nanomaterial selection, performance optimization, multimodal therapy, visualization strategies, and targeting strategies. Furthermore, an outlook on further improvements of PTT/CDT is provided, emphasizing significant scientific issues that require remediation for clinical translation. This article is categorized under: Diagnostic Tools > in vivo Nanodiagnostics and Imaging Therapeutic Approaches and Drug Discovery > Nanomedicine for Oncologic Disease.

9.
Cancer Lett ; 500: 41-50, 2021 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-33359275

RESUMO

Mitochondria-targeted mild-temperature photothermal therapy (MT-PTT) is a promising strategy that can maximize anticancer effects and reduce adverse reactions. Here, a novel photosensitizer with mitochondrial targeting based on IR780 iodide and heat shock protein 90 inhibitor (BIIB021), which can passively accumulate in MCF-7 cells and achieve effective MT-PTT effect is synthesized. The prepared PEG-IR780-BIIB021 nano-micelles possess considerable biocompatibility and biological stability, with an encapsulation efficiency of about 84% for BIIB021. They can selectively enrich in mitochondria, and release BIIB021 after NIR irradiation to reduce cell tolerance to heat, thereby reducing the mitochondrial membrane potential and rapidly affecting key intrinsic apoptotic factors (Cyt-C, Caspase-9, Bcl-2 and Bax) to achieve the effect of MT-PTT. It is believed that mitochondria-targeted MT-PTT generated by the PEG-IR780-BIIB021 nano-micelles is a promising therapeutic strategy in clinical practice.


Assuntos
Neoplasias da Mama/terapia , Proteínas de Choque Térmico HSP90/genética , Indóis/farmacologia , Terapia Fototérmica , Animais , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Feminino , Xenoenxertos , Humanos , Células MCF-7 , Camundongos , Micelas , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/genética , Temperatura
10.
Bioact Mater ; 6(3): 740-748, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33024895

RESUMO

Zeolitic Imidazole Frameworks (ZIFs) are widely applied in nanomedicine for their high drug loading, suitable pore size, pH-responsive drug release, and so on. However, fast drug release during circulation, unexpected toxicity to mice major organs, undesirable long-term accumulation in the lung and even death currently hinder their in vivo biomedical applications. Herein, we report an amorphous ZIF-8 (aZIF-8) with high loading of 5-Fu through pressure-induced amorphization. This nano-system avoids early drug release during circulation and provides tumor microenvironment-responsive drug release with improved in vitro cell viability, and survival rate in in vivo evaluations as compared to ZIF-8. Furthermore, aZIF-8 shows longer blood circulation and lower lung accumulation than ZIF-8 at same injected doses. Less drug release during circulation, longer blood circulation, and better biocompatibility of aZIF-8/5-Fu significantly improves its therapeutic efficacy in ECA-109 tumor-bearing mouse, and result in 100% survival rate over 50 days after treatment. Therefore, aZIF-8 with favorable biocompatibility and long blood circulation is expected to be a promising nano-system for efficacious cancer therapy in vivo.

11.
Nanoscale ; 12(48): 24311-24330, 2020 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-33300527

RESUMO

At present, cancer is obviously a major threat to human health worldwide. Accurate diagnosis and treatment are in great demand and have become an effective method to alleviate the development of cancer and improve the survival rate of patients. A large number of theranostic probes that combine diagnosis and treatment methods have been developed as promising tools for tumor precision medicine. Among them, fluorescent theranostic probes have developed rapidly in the frontier research field of precision medicine with their real time, low toxicity, and high-resolution merit. Therefore, this review focuses on recent advances in the development of fluorescent theranostic probes, as well as their applications for cancer diagnosis and treatment. Initially, small-molecule fluorescent theranostic probes mainly including tumor microenvironment-responsive fluorescent prodrugs and phototherapeutic probes were introduced. Subsequently, nanocomposite probes are expounded based on four types of nano-fluorescent particles combining different therapies (chemotherapy, photothermal therapy, photodynamic therapy, gene therapy, etc.). Then, the capsule-type "all in one" probes, which occupy an important position in theranostic probes, are summarized according to the surface carrier type. This review aims to present a comprehensive guide for researchers in the field of tumor-related theranostic probe design and development.


Assuntos
Neoplasias , Medicina de Precisão , Corantes Fluorescentes , Humanos , Neoplasias/diagnóstico , Neoplasias/terapia , Nanomedicina Teranóstica , Microambiente Tumoral
12.
Small ; 16(41): e2002445, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32954652

RESUMO

The quest for an all-organic nanosystem with negligible cytotoxicity and remarkable in vivo tumor theranostic capability is inescapably unending. Hitherto, the landscape of available photothermal agents is dominated by metal-based nanoparticles (NPs) with attendant in vivo negatives. Here, an all-organic-composed theranostic nanosystem with outstanding biocompatibility for fluorescence image-guided tumor photothermal therapy, and as a potential alternative to metal-based photothermal agents is developed. This is rationally achieved by compartmentalizing indocyanine green (ICG) in glycol chitosan (GC)-polypyrrole (PP) nanocarrier to form hybrid ICG@GC-PP NPs (≈65 nm). The compartmentalization strategy, alongside the high photothermal conversion ability of PP jointly enhances the low photostability of free ICG. Advantageously, ICG@GC-PP is endowed with an impeccable in vivo performance by the well-known biocompatibility track records of its individual tri organo-components (GC, PP, and ICG). As a proof of concept, ICG@GC-PP NPs enables a sufficiently prolonged tumor diagnosis by fluorescence imaging up to 20 h post-injection. Furthermore, owing to the complementary heating performances of PP and ICG, ICG@GC-PP NPs-treated mice by one-time near-infrared irradiation exhibit total tumor regression within 14 days post-treatment. Therefore, leveraging the underlying benefits of this study will help to guide the development of new all-organic biocompatible systems in synergism, for safer tumor theranostics.


Assuntos
Nanopartículas , Neoplasias , Animais , Linhagem Celular Tumoral , Verde de Indocianina , Camundongos , Neoplasias/diagnóstico por imagem , Neoplasias/terapia , Imagem Óptica , Fototerapia , Polímeros , Pirróis , Nanomedicina Teranóstica
13.
J Mater Chem B ; 8(36): 8356-8367, 2020 09 23.
Artigo em Inglês | MEDLINE | ID: mdl-32794542

RESUMO

The integration of advanced diagnostic contrast agents with versatile therapeutic drugs is an effective method for cancer treatment. However, combining various biocompatible theranostic modalities into a single platform at the nanoscale is a challenging assignment. In this work, we report a simple chemical synthetic route for producing a homogeneous hybrid nanoflower shaped morphology based on Au@Mn3O4 magneto-plasmonic nanomaterials. The synthetic mechanism of the nanoflowers is well-matched with the heteroepitaxial growth phenomena by which the nano-petals of Mn3O4 generated on the surface of the Au core. The food and drug administration (FDA) in the USA approved the use of triblock polymer Pluronic F-127 to enhance the biocompatibility of Au@Mn3O4 hybrid nanoflowers. The prepared hybrid nanoflowers produce a significant photothermal heating effect with a thermal transduction efficiency of 38%, comparable to the nanorods and nanoparticles of gold (Au). The hybrid junction reveals promising optical and magnetic properties and the prepared Au@Mn3O4 nanoflowers not only exhibit strong near-infrared (NIR) absorption to produce excellent photothermal efficacy under irradiation with an 808 nm NIR laser, but also demonstrate a significant T1-weighted magnetic resonance (MR) image enhancement in vitro and in vivo. The histopathology assessments indicate only negligible toxicity of the nanoflowers to major organs. Therefore, the hybrid Au@Mn3O4 nanoflowers exhibit great potential in T1-weighted MR-imaging and photothermal therapy, opening up new possibilities for synthesizing novel bio-compatible, homogeneous, and shape controllable nanostructures with multifunctional applications.


Assuntos
Meios de Contraste/uso terapêutico , Nanopartículas Metálicas/uso terapêutico , Neoplasias/diagnóstico por imagem , Neoplasias/tratamento farmacológico , Animais , Linhagem Celular Tumoral , Meios de Contraste/síntese química , Meios de Contraste/efeitos da radiação , Feminino , Ouro/química , Ouro/efeitos da radiação , Ouro/uso terapêutico , Raios Infravermelhos , Imageamento por Ressonância Magnética/métodos , Compostos de Manganês/química , Compostos de Manganês/efeitos da radiação , Compostos de Manganês/uso terapêutico , Nanopartículas Metálicas/química , Nanopartículas Metálicas/efeitos da radiação , Camundongos Nus , Óxidos/química , Óxidos/efeitos da radiação , Óxidos/uso terapêutico , Terapia Fototérmica/métodos , Nanomedicina Teranóstica
14.
Bioconjug Chem ; 31(7): 1708-1723, 2020 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-32538089

RESUMO

Bacterial infections in wounds often delay the healing process, and may seriously threaten human life. It is urgent to develop wound dressings to effectively detect and treat bacterial infections. Nanoparticles have been extensively used in wound dressings because of their specific properties. This review highlights the recent progress on nanoparticle-based wound dressings for bacterial detection and therapy. Specifically, nanoparticles have been applied as intrinsic antibacterial agents or drug delivery vehicles to treat bacteria in wounds. Moreover, nanoparticles with photothermal or photodynamic property have also been explored to endow wound dressings with significant optical properties to further enhance their bactericidal effect. More interestingly, nanoparticle-based smart dressings have been recently explored for bacteria detection and treatment, which enables an accurate assessment of bacterial infection and a more precise control of on-demand therapy.


Assuntos
Infecções Bacterianas/diagnóstico , Infecções Bacterianas/tratamento farmacológico , Bandagens , Nanopartículas Metálicas , Ferimentos e Lesões/terapia , Antibacterianos/uso terapêutico , Portadores de Fármacos , Humanos , Cicatrização , Ferimentos e Lesões/microbiologia
15.
J Mater Chem B ; 8(31): 6837-6844, 2020 08 21.
Artigo em Inglês | MEDLINE | ID: mdl-32510101

RESUMO

Ultrasound cavitation therapy has attracted much attention in recent years because the cavitation of microbubbles can be leveraged to boost the infiltration of chemotherapeutic drugs into cancer tissues. For breast cancer therapy, most of the previously reported microbubbles lack specific targeting capacity and permeability. In this study, we have successfully fabricated Y1 receptor ligand (NPY)-modified bubbles, and examined their therapeutic efficacies as size-dependent functions with or without NPY targeting. To achieve this, four types of micro-scale bubbles (MBs or MBs-NPY) and nano-scale bubbles (NBs or NBs-NPY) were comprehensively evaluated. In vivo results indicated that the NBs-NPY group with doxorubicin (DOX) under ultrasound irradiation showed a high tumor suppression effect and a prolonged survival time. Furthermore, the NBs-NPY with DOX group exhibited minimal damage to mouse vital organs, which points to the considerable tolerance of the proposed nanosystem for efficacious breast cancer therapy. In summary, these findings suggest that the developed NPY-targeted NBs could have a broad application prospect in ultrasound cavitation chemotherapy of Y1 receptor-overexpressed breast cancer.


Assuntos
Neoplasias da Mama/reabilitação , Regulação Neoplásica da Expressão Gênica , Nanomedicina/métodos , Receptores de Neuropeptídeo Y/metabolismo , Terapia por Ultrassom/métodos , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Doxorrubicina/farmacologia , Humanos
16.
Nanoscale ; 12(24): 12779-12789, 2020 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-32347269

RESUMO

Zeolitic imidazolate frameworks (ZIFs) as emerging porous materials have attracted remarkable attention for their unprecedented porosity and acidic sensitive degradation that enables high drug loading and microenvironment responsive fast payload release. However, the limited functions and disadvantages of ZIFs such as early drug release, potential cytotoxicity inducing damage to major organs, and even death of animals, impede their further biomedical application. In this work, we report the first tandem post-synthetic modification of ZIF-7 with both metal ions and organic ligands. Inspired by the benzimidazole-like inhibitors that are similar to the organic ligand of ZIF-7, a chemokine (C-X-C motif) receptor 4 (CXCR4) inhibitor AMD-070 (AMD) and magnesium ions (Mn2+) were successfully tandem exchanged to the ZIF-7 framework, forming an active-targeting framework AMD-ZIF-7(Mn) for CXCR4-overexpressed esophageal squamous cell cancer. The obtained AMD-ZIF-7(Mn) showed good biocompatibility in vitro and in vivo. Meanwhile, it exhibited an excellent T1-weighted magnetic resonance imaging performance and CXCR4 targeting ability. With 5-Fu loading, AMD-ZIF-7(Mn)/5-Fu showed a synergistic therapeutic effect in DNA damage and CXCR4 inhibition of esophageal squamous cell cancer. Therefore, we propose a structural reconstruction method to effectively explore and improve the biomedical application of ZIFs in esophageal squamous cell cancer theranostics.


Assuntos
Carcinoma de Células Escamosas , Neoplasias Esofágicas , Zeolitas , Animais , Carcinoma de Células Escamosas/diagnóstico por imagem , Carcinoma de Células Escamosas/tratamento farmacológico , Diagnóstico por Imagem , Liberação Controlada de Fármacos , Neoplasias Esofágicas/diagnóstico por imagem , Neoplasias Esofágicas/tratamento farmacológico , Microambiente Tumoral
17.
J Hazard Mater ; 392: 122288, 2020 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-32109794

RESUMO

This research reports a new mercury adsorbent in which Fe3O4 as a core was embedded into the shell of ZIF-90 in a one-pot synthesis and the subsequent post synthesis modification (PSM) of its surface with cysteine covalently, via a Schiff's base reaction. Poly acrylic acid (PAA) was capped on the surface of nanoparticles to prevent agglomeration of the nanoparticles. In addition, -COOH groups of PAA coordinated with Zn2+ of ZIF-90 and this provided the platform for ZIF-90 to grow on the nanoparticles forming the core-shell structure. Based on the strong interactions between the thiol groups on the adsorbent and mercury ions as elucidated by the XPS analysis, the as-synthesized adsorbent showed selectivity for Hg2+. The sorbent exhibited high adsorption capacity of 900 mg g-1 towards Hg2+ as calculated at pH 4 and the adsorption kinetics followed pseudo-second-order kinetics model better. The Hg2+ loaded adsorbent was easily regenerated and it maintained about 70 % efficiency after the third use. Low-cost, readily available and green materials, facile preparation, efficient removal and the breakthrough in three times recyclability give the novel ZIF-90 based hybrid nanoadsorbent wide prospects in the field of environmental remediation as a good adsorbent for Hg2+ removal in wastewater.


Assuntos
Resinas Acrílicas/química , Cisteína/química , Imidazóis/química , Nanopartículas de Magnetita/química , Mercúrio/química , Poluentes Químicos da Água/química , Zeolitas/química , Adsorção , Águas Residuárias , Purificação da Água/métodos
18.
J Mater Chem B ; 8(12): 2381-2392, 2020 03 25.
Artigo em Inglês | MEDLINE | ID: mdl-32100802

RESUMO

A broad range of investigation methods and frameworks are currently used to throughly study the elasticity of various types of micro/nanoparticles (MNPs) with different properties and to explore the effect of such properties on their interactions with biological species. Specifically, the elasticity of MNPs serves as a key influencing factor with respect to important aspects of phagocytosis, such as the clathrin-mediated phagocytosis, caveolae-mediated phagocytosis, macropinocytosis, and cell membrane fusion. Achieving a clear understanding of the relationships that exist between the elasticity of MNPs and their phagocytic processes is essential to improve their performance in drug delivery, which is related to aspects such as circulation lifetime in blood, accumulation time in tissues, and resistance to metabolism. Resolving such aspects is very challenging, and related efforts require using the right tools/methods, which are not always easy to identify. This review aims to facilitate this by summarizing and comparing different cell phagocytosis pathways, while considering various MNPs exhibiting different elastic properties, shape change capabilities, and their effect on cellular uptake. We conduct an overview of the advantages exhibited by different MNPs with respect to both in vitro and in vivo delivery, taking computational simulation analysis and experimental results into account. This study will provide a guide for how to investigate various types of MNPs in terms of their elastic properties, together with their biomedical effects that rely on phagocytosis.


Assuntos
Nanopartículas/química , Sistemas de Liberação de Medicamentos , Elasticidade , Simulação de Dinâmica Molecular , Tamanho da Partícula , Fagocitose , Propriedades de Superfície
19.
Small ; 16(11): e1906870, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32091159

RESUMO

The market of available contrast agents for clinical magnetic resonance imaging (MRI) has been dominated by gadolinium (Gd) chelates based T1 contrast agents for decades. However, there are growing concerns about their safety because they are retained in the body and are nephrotoxic, which necessitated a warning by the U.S. Food and Drug Administration against the use of such contrast agents. To ameliorate these problems, it is necessary to improve the MRI efficiency of such contrast agents to allow the administration of much reduced dosages. In this study, a ten-gram-scale facile method is developed to synthesize organogadolinium complex nanoparticles (i.e., reductive bovine serum albumin stabilized Gd-salicylate nanoparticles, GdSalNPs-rBSA) with high r1 value of 19.51 mm-1 s-1 and very low r2 /r1 ratio of 1.21 (B0 = 1.5 T) for high-contrast T1 -weighted MRI of tumors. The GdSalNPs-rBSA nanoparticles possess more advantages including low synthesis cost (≈0.54 USD per g), long in vivo circulation time (t1/2 = 6.13 h), almost no Gd3+ release, and excellent biosafety. Moreover, the GdSalNPs-rBSA nanoparticles demonstrate excellent in vivo MRI contrast enhancement (signal-to-noise ratio (ΔSNR) ≈ 220%) for tumor diagnosis.


Assuntos
Nanopartículas , Neoplasias , Meios de Contraste , Gadolínio , Humanos , Imageamento por Ressonância Magnética , Neoplasias/diagnóstico por imagem
20.
Colloids Surf B Biointerfaces ; 189: 110837, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32058250

RESUMO

Epithelial ovarian cancer is still the leading cause of death in gynecology due to its resistance to platinum-based first-line chemotherapeutic drugs. The utilization of mitochondria-targeted drugs has become an important direction in anti-tumor drug research and development. In this work, cisplatin (DDP)-loaded ZIF-90 with mitochondrial-targeting was synthesized at room temperature with a high drug loading (11.7 %, calculated based on Pt content). The ZIF-90@DDP showed high cellular uptake and less toxicity in both non- and DDP-resistant ovarian cancer cells with effective pH- and ATP-responsive drug release. Both mitochondria-targeting and responsive drug release could increase the drug concentration in mitochondria of drug-resistant cancer cells to reverse such resistance. Conclusively, the mitochondria-targeting ZIF-90@DDP with high drug loading could trigger responsive drug release in mitochondria of epithelial ovarian cancer cells, inhibit DPP-resistant epithelial ovarian cancer cells, and reverse drug resistance.


Assuntos
Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Imidazóis/farmacologia , Mitocôndrias/efeitos dos fármacos , Neoplasias Ovarianas/tratamento farmacológico , Zeolitas/farmacologia , Antineoplásicos/farmacologia , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Cisplatino/farmacologia , Relação Dose-Resposta a Droga , Portadores de Fármacos/síntese química , Portadores de Fármacos/química , Portadores de Fármacos/farmacologia , Liberação Controlada de Fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Feminino , Humanos , Imidazóis/síntese química , Imidazóis/química , Mitocôndrias/metabolismo , Estrutura Molecular , Neoplasias Ovarianas/metabolismo , Neoplasias Ovarianas/patologia , Tamanho da Partícula , Relação Estrutura-Atividade , Propriedades de Superfície , Células Tumorais Cultivadas , Zeolitas/síntese química , Zeolitas/química
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