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1.
J Mater Chem B ; 2024 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-38895823

RESUMO

In recent decades, orthopedic implants have been widely used as materials to replace human bone tissue functions. Among these, metal implants play a crucial role. Metals with better chemical stability, such as stainless steel, titanium alloys, and cobalt-chromium-molybdenum (CoCrMo) alloy, are commonly used for long-term applications. However, good chemical stability can result in poor tissue integration between the tissue and the implant, leading to potential inflammation risks. This study creates hydrogenated CoCrMo (H-CoCrMo) surfaces, which have shown promise as anti-inflammatory orthopedic implants. Using the electrochemical cathodic hydrogen-charging method, the surface of the CoCrMo alloy was hydrogenated, resulting in improved biocompatibility, reduced free radicals, and an anti-inflammatory response. Hydrogen diffusion to a depth of approximately 106 ± 27 nm on the surface facilitated these effects. This hydrogen-rich surface demonstrated a reduction of 85.2% in free radicals, enhanced hydrophilicity as evidenced by a decrease in a contact angle from 83.5 ± 1.9° to 52.4 ± 2.2°, and an increase of 11.4% in hydroxyapatite deposition surface coverage. The cell study results revealed a suppression of osteosarcoma cell activity to 50.8 ± 2.9%. Finally, the in vivo test suggested the promotion of new bone formation and a reduced inflammatory response. These findings suggest that electrochemical hydrogen charging can effectively modify CoCrMo surfaces, offering a potential solution for improving orthopedic implant outcomes through anti-inflammatory mechanisms.

2.
ACS Appl Mater Interfaces ; 16(20): 25622-25636, 2024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38739745

RESUMO

Breast cancer is a malignant tumor with a high mortality rate among women. Therefore, it is necessary to develop novel therapies to effectively treat this disease. In this study, iron selenide nanorods (FeSe2 NRs) were designed for use in magnetic hyperthermic, photothermal, and chemodynamic therapy (MHT/PTT/CDT) for breast cancer. To illustrate their efficacy, FeSe2 NRs were modified with the chemotherapeutic agent methotrexate (MTX). MTX-modified FeSe2 (FeSe2-MTX) exhibited excellent controlled drug release properties. Fe2+ released from FeSe2 NRs induced the release of •OH from H2O2 via a Fenton/Fenton-like reaction, enhancing the efficacy of CDT. Under alternating magnetic field (AMF) stimulation and 808 nm laser irradiation, FeSe2-MTX exerted potent hyperthermic and photothermal effects by suppressing tumor growth in a breast cancer nude mouse model. In addition, FeSe2 NRs can be used for magnetic resonance imaging in vivo by incorporating their superparamagnetic characteristics into a single nanomaterial. Overall, we presented a novel technique for the precise delivery of functional nanosystems to tumors that can enhance the efficacy of breast cancer treatment.


Assuntos
Neoplasias da Mama , Hipertermia Induzida , Metotrexato , Camundongos Nus , Nanotubos , Metotrexato/química , Metotrexato/farmacologia , Animais , Nanotubos/química , Camundongos , Feminino , Humanos , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Neoplasias da Mama/terapia , Camundongos Endogâmicos BALB C , Terapia Fototérmica , Ferro/química , Compostos de Selênio/química , Compostos de Selênio/farmacologia , Compostos de Selênio/efeitos da radiação , Linhagem Celular Tumoral , Raios Infravermelhos
3.
Chemosphere ; 358: 142237, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38705406

RESUMO

In this study, a novel Ce2MgMoO6/CNFs (cerium magnesium molybdite double perovskite decorated on carbon nanofibers) nanocomposite was developed for selective and ultra-sensitive detection of ciprofloxacin (CFX). Physical characterization and analytical techniques were used to explore the morphology, structure, and electrocatalytic characteristics of the Ce2MgMoO6/CNFs nanocomposite. The sensor has a wide linear range (0.005-7.71 µM and 9.75-77.71 µM), a low limit of detection (0.012 µM), high sensitivity (0.807 µA µM-1 cm-2 nM), remarkable repeatability, and an appreciable storage stability. Here, we used density functional theory to investigate CFX and oxidized CFX as well as the locations of the energy levels and electron transfer sites. Furthermore, the Ce2MgMoO6/CNFs-modified electrode was successfully tested in food samples (milk and honey), indicating an acceptable response with a recovery percentage and relative standard deviation of less than 4%, which is comparable to that of GC-MS. Finally, the developed sensor exhibited high selectivity and stability for CFX detection.


Assuntos
Carbono , Ciprofloxacina , Mel , Leite , Nanocompostos , Nanofibras , Óxidos , Nanocompostos/química , Ciprofloxacina/análise , Ciprofloxacina/química , Óxidos/química , Leite/química , Nanofibras/química , Animais , Mel/análise , Carbono/química , Molibdênio/química , Limite de Detecção , Compostos de Cálcio/química , Titânio/química , Teoria da Densidade Funcional , Técnicas Eletroquímicas/métodos , Cério/química , Contaminação de Alimentos/análise , Eletrodos , Magnésio/química , Magnésio/análise
4.
J Mater Chem B ; 12(15): 3569-3593, 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38494982

RESUMO

In recent years, inorganic nanoparticles (NPs) have attracted increasing attention as potential theranostic agents in the field of oncology. Photothermal therapy (PTT) is a minimally invasive technique that uses nanoparticles to produce heat from light to kill cancer cells. PTT requires two essential elements: a photothermal agent (PTA) and near-infrared (NIR) radiation. The role of PTAs is to absorb NIR, which subsequently triggers hyperthermia within cancer cells. By raising the temperature in the tumor microenvironment (TME), PTT causes damage to the cancer cells. Nanoparticles (NPs) are instrumental in PTT given that they facilitate the passive and active targeting of the PTA to the TME, making them crucial for the effectiveness of the treatment. In addition, specific targeting can be achieved through their enhanced permeation and retention effect. Thus, owing to their significant advantages, such as altering the morphology and surface characteristics of nanocarriers comprised of PTA, NPs have been exploited to facilitate tumor regression significantly. This review highlights the properties of PTAs, the mechanism of PTT, and the results obtained from the improved curative efficacy of PTT by utilizing NPs platforms.


Assuntos
Hipertermia Induzida , Nanopartículas , Neoplasias , Humanos , Fototerapia/métodos , Hipertermia Induzida/métodos , Neoplasias/tratamento farmacológico , Neoplasias/patologia , Nanomedicina Teranóstica/métodos , Microambiente Tumoral
5.
Chemosphere ; 355: 141744, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38522669

RESUMO

Pesticides pollute natural water reservoirs through persistent accumulation. Therefore, their toxicity and degradability are serious issues. Carbendazim (CBZ) is a pesticide used against fungal infections in agricultural crops, and its overexploitation detrimentally affects aquatic ecosystems and organisms. It is necessary to design a logical, efficient, and field-deployable method for monitoring the amount of CBZ in environmental samples. Herein, a nano-engineered bismuth selenide (Bi2Se3)/functionalized carbon nanofiber (f-CNF) nanocomposite was utilized as an electrocatalyst to fabricate an electrochemical sensing platform for CBZ. Bi2Se3/f-CNF exhibited a substantial electroactive surface area, high electrocatalytic activity, and high conductivity owing to the synergistic interaction of Bi2Se3 with f-CNF. The structural chemical compositions and morphology of the Bi2Se3/f-CNF nanocomposite were confirmed by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and field-emission scanning electron microscopy (FESEM). Electrochemical analysis was carried out using cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), and differential pulse voltammetry (DPV). The voltammetry and impedance experiments exposed that the Bi2Se3/f-CNF-modified GCE has attained adequate electrocatalytic function with amended features of electron transportation (Rct = 35.93 Ω) and improved reaction sites (0.082 cm2) accessible by CBZ moiety along with exemplary electrochemical stability (98.92%). The Bi2Se3/f-CNF nanocomposite exhibited higher sensitivity of 0.2974 µA µM-1cm-2 and a remarkably low limit of detection (LOD) of 1.04 nM at a broad linera range 0.001-100 µM. The practicability of the nanocomposite was tested in environmental (tap and pond water) samples, which supports excellent signal amplification with satisfactory recoveries. Hence, the Bi2Se3/f-CNF nanocomposite is a promising electrode modifier for detecting CBZ.


Assuntos
Benzimidazóis , Bismuto , Carbamatos , Carbono , Nanofibras , Compostos de Selênio , Carbono/química , Nanofibras/química , Ecossistema , Água , Técnicas Eletroquímicas/métodos , Eletrodos
6.
Biomater Adv ; 158: 213778, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38325029

RESUMO

Combining chemodynamic therapy (CDT) with photothermal therapy (PTT) has developed as a promising approach for cancer treatment, as it enhances therapeutic efficiency through redox reactions and external laser induction. In this study, we designed metal organic framework (MOF) -derived Cu5Zn8/HPCNC through a carbonization process and decorated them with gold nanoparticles (Au@Cu5Zn8/HPCNC). The resulting nanoparticles were employed as a photothermal agent and Fenton catalyst. The Fenton reaction facilitated the conversation of Cu2+ to Cu+ through reaction with local H2O2, generating reactive hydroxyl radicals (·OH) with potent cytotoxic effects. To enhance the Fenton-like reaction and achieve combined therapy, laser irradiation of the Au@Cu5Zn8/HPCNC induced efficient photothermal therapy by generating localized heat. With a significantly increased absorption of Au@Cu5Zn8/HPCNC at 808 nm, the photothermal efficiency was determined to be 57.45 %. Additionally, Au@Cu5Zn8/HPCNC demonstrated potential as a contrast agent for magnetic resonance imaging (MRI) of cancers. Furthermore, the synergistic combination of PTT and CDT significantly inhibited tumor growth. This integrated approach of PTT and CDT holds great promise for cancer therapy, offering enhanced CDT and modulation of the tumor microenvironment (TME), and opening new avenues in the fight against cancer.


Assuntos
Nanopartículas Metálicas , Estruturas Metalorgânicas , Ouro , Nanopartículas Metálicas/uso terapêutico , Terapia Fototérmica , Porosidade , Microambiente Tumoral , Carbono , Imageamento por Ressonância Magnética , Zinco
7.
Colloids Surf B Biointerfaces ; 234: 113755, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38241894

RESUMO

In terms of cancer-related deaths among women, breast cancer (BC) is the most common. Clinically, human epidermal growth receptor 2 (HER2) is one of the most commonly used diagnostic biomarkers for facilitating BC cell proliferation and malignant growth. In this study, a disposable gold electrode (DGE) modified with gold nanoparticle-decorated Ti3C2Tx (Au/MXene) was utilized as a sensing platform to immobilize the capturing antibody (Ab1/Au/MXene). Subsequently, nitrogen-doped graphene (NG) with a metal-organic framework (MOF)-derived copper-manganese-cobalt oxide, tagged as NG/CuMnCoOx, was used as a probe to label the detection antibody (Ab2). A sandwich-type immunosensor (NG/CuMnCoOx/Ab2/HER2-ECD /Ab1/Au/MXene/DGE) was developed to quantify HER2-ECD. NG/CuMnCoOx enhances the conductivity, electrocatalytic active sites, and surface area to immobilize Ab2. In addition, Au/MXene facilitates electron transport and captures more Ab1 on its surface. Under optimal conditions, the resultant immunosensor displayed an excellent linear range of 0.0001 to 50.0 ng. mL-1. The detection limit was 0.757 pg·mL-1 with excellent selectivity, appreciable reproducibility, and high stability. Moreover, the applicability for determining HER2-ECD in human serum samples indicates its ability to monitor tumor markers clinically.


Assuntos
Técnicas Biossensoriais , Neoplasias da Mama , Grafite , Compostos de Manganês , Nanopartículas Metálicas , Estruturas Metalorgânicas , Nitritos , Óxidos , Elementos de Transição , Humanos , Feminino , Biomarcadores Tumorais , Grafite/química , Estruturas Metalorgânicas/química , Ouro/química , Reprodutibilidade dos Testes , Nanopartículas Metálicas/química , Neoplasias da Mama/diagnóstico , Imunoensaio , Técnicas Eletroquímicas , Limite de Detecção , Anticorpos Imobilizados/química
8.
Adv Mater ; 36(23): e2310789, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38253339

RESUMO

Conventional osteogenic platforms utilize active growth factors to repair bone defects that are extensive in size, but they can adversely affect patient health. Here, an unconventional osteogenic platform is reported that functions by promoting capture of inactive osteogenic growth factor molecules to the site of cell growth for subsequent integrin-mediated activation, using a recombinant fragment of latent transforming growth factor beta-binding protein-1 (rLTBP1). It is shown that rLTBP1 binds to the growth-factor- and integrin-binding domains of fibronectin on poly(ethyl acrylate) surfaces, which immobilizes rLTBP1 and promotes the binding of latency associated peptide (LAP), within which inactive transforming growth factor beta 1 (TGF-ß1) is bound. rLTBP1 facilitates the interaction of LAP with integrin ß1 and the subsequent mechanically driven release of TGF-ß1 to stimulate canonical TGF-ß1 signaling, activating osteogenic marker expression in vitro and complete regeneration of a critical-sized bone defect in vivo.


Assuntos
Osteogênese , Fator de Crescimento Transformador beta1 , Animais , Humanos , Fator de Crescimento Transformador beta1/metabolismo , Fibronectinas/metabolismo , Fibronectinas/química , Proteínas de Ligação a TGF-beta Latente/metabolismo , Proteínas de Ligação a TGF-beta Latente/química , Regeneração Óssea , Propriedades de Superfície , Integrinas/metabolismo , Ligação Proteica , Integrina beta1/metabolismo , Transdução de Sinais
9.
Biomater Adv ; 157: 213724, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38134729

RESUMO

Traditional cancer treatments are ineffective and cause severe adverse effects. Thus, the development of chemodynamic therapy (CDT) has the potential for in situ catalysis of endogenous molecules into highly toxic species, which would then effectively destroy cancer cells. However, the shortage of high-performance nanomaterials hinders the broad clinical application of this approach. In present study, an effective therapeutic platform was developed using a simple hydrothermal method for the in-situ activation of the Fenton reaction within the tumor microenvironment (TME) to generate substantial quantities of •OH and ultimately destroy cancer cells, which could be further synergistically increased by photothermal therapy (PHT) and magnetic hyperthermia (MHT) aided by FeMoO4 nanorods (NRs). The produced FeMoO4 NRs were used as MHT/PHT and Fenton catalysts. The photothermal conversion efficiency of the FeMoO4 NRs was 31.75 %. In vitro and \ experiments demonstrated that the synergistic combination of MHT/PHT/CDT notably improved anticancer efficacy. This work reveals the significant efficacy of CDT aided by both photothermal and magnetic hyperthermia and offers a feasible strategy for the use of iron-based nanoparticles in the field of biomedical applications.


Assuntos
Hipertermia Induzida , Nanoestruturas , Fototerapia , Microambiente Tumoral , Fenômenos Magnéticos
10.
ACS Appl Mater Interfaces ; 15(28): 33335-33347, 2023 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-37403930

RESUMO

This study prepared dumbbell-shaped titanium dioxide (TiO2)/gold nanorods (AuNRs) coated with mesoporous silica shells (mS) (AuNRs-TiO2@mS). Methotrexate (MTX) was further loaded into the AuNRs-TiO2@mS, and then upconversion nanoparticles (UCNPs) were decorated to form AuNRs-TiO2@mS-MTX: UCNP nanocomposites. TiO2 is used as an intense photosensitizer (PS) to produce cytotoxic reactive oxygen species (ROS), leading to photodynamic therapy (PDT). Concurrently, AuNRs exhibited intense photothermal therapy (PTT) effects and photothermal conversion efficiency. In vitro results suggested that these nanocomposites can kill oral cancer cells (HSC-3) without toxicity through irradiation of NIR laser, owing to the synergistic effect. The in vivo studies indicated that these nanocomposites exhibited excellent antitumor effects through synergistic PDT/PTT/chemotherapy under a near-infrared (NIR) 808 nm laser irradiation. Thus, these AuNRs-TiO2@mS: UCNP nanocomposites have great potential to undergo deep tissue penetration with enhanced synergistic effects through NIR-triggered light for cancer treatment.


Assuntos
Nanopartículas , Nanotubos , Neoplasias , Fotoquimioterapia , Fotoquimioterapia/métodos , Metotrexato/farmacologia , Dióxido de Silício , Ouro/farmacologia , Fármacos Fotossensibilizantes/farmacologia , Fármacos Fotossensibilizantes/uso terapêutico , Nanotubos/efeitos da radiação , Neoplasias/tratamento farmacológico
11.
Food Chem ; 426: 136609, 2023 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-37331138

RESUMO

In this study, a polydopamine/titanium carbide adorned with gold nanoparticles (Au@PDA/TiC) composite was prepared by a simple stirring technique and it was used for the dual-technique detection of ß-Nicotinamide adenine dinucleotide (NADH). The Au@PDA/TiC-modified glassy carbon electrode (GCE) oxidized NADH at a very low oxidation potential of approximately 0.60 V vs Ag/AgCl in pH = 7.0 (0.1 M PBS) via the transfer of two electrons and one proton (from NADH to NAD+). Based on the (i-t) amperometry mode, NADH can be quantified with a linear range of 0.018-674 µM and LOD of 0.0062 µM. In addition to the DPV mode, the electrochemical sensor had a linearity of 5-450 µM with a LOD of 3.17 µM. The developed sensor exhibited remarkable analytical performances concerning high sensitivity, electrocatalytic activity, low detection limit, wide linearity, appreciable specificity, repeatability, stability, reproducibility, and adequate recovery results in food, environmental and biological samples.


Assuntos
Nanopartículas Metálicas , NAD , Ouro , Reprodutibilidade dos Testes , Carbono , Eletrodos , Técnicas Eletroquímicas/métodos
12.
Nanomedicine ; 48: 102652, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36623714

RESUMO

Metal-organic frameworks (MOFs) have emerged as attractive candidates in cancer theranostics due to their ability to envelop magnetic nanoparticles, resulting in reduced cytotoxicity and high porosity, enabling chemodrug encapsulation. Here, FeAu alloy nanoparticles (FeAu NPs) are synthesized and coated with MIL-100(Fe) MOFs to fabricate FeAu@MOF nanostructures. We encapsulated Doxorubicin within the nanostructures and evaluated the suitability of this platform for medical imaging and cancer theranostics. FeAu@MOF nanostructures (FeAu@MIL-100(Fe)) exhibited superparamagnetism, magnetic hyperthermia behavior and displayed DOX encapsulation and release efficiency of 69.95 % and 97.19 %, respectively, when stimulated with alternating magnetic field (AMF). In-vitro experiments showed that AMF-induced hyperthermia resulted in 90 % HSC-3 oral squamous carcinoma cell death, indicating application in cancer theranostics. Finally, in an in-vivo mouse model, FeAu@MOF nanostructures improved image contrast, reduced tumor volume by 30-fold and tumor weight by 10-fold, which translated to enhancement in cumulative survival, highlighting the prospect of this platform for oral cancer treatment.


Assuntos
Carcinoma , Hipertermia Induzida , Estruturas Metalorgânicas , Neoplasias Bucais , Nanoestruturas , Animais , Camundongos , Estruturas Metalorgânicas/química , Medicina de Precisão , Doxorrubicina/farmacologia , Doxorrubicina/uso terapêutico , Doxorrubicina/química , Neoplasias Bucais/diagnóstico por imagem , Neoplasias Bucais/tratamento farmacológico , Diagnóstico por Imagem , Fenômenos Magnéticos , Nanomedicina Teranóstica
13.
Colloids Surf B Biointerfaces ; 222: 113033, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36455362

RESUMO

The current study reports the design and construction of enzyme-free sensor using N-doped graphene quantum dots (N-GQDs)-decorated tin sulfide nanosheets (SnS2) for in situ monitoring of H2O2 secreted by human breast cancer cells. N-GQDs nanoparticles having a size of less than 1 nm were incorporated into SnS2 nanosheets to form an N-GQDs@SnS2 nanocomposite using a simple hydrothermal approach. The resulting hybrid material was an excellent electrocatalyst for the reduction of H2O2, owing to the combined properties of highly conductive N-GQDs and SnS2 nanosheets. The N-GQDs@SnS2-based sensing platform demonstrated substantial sensing ability, with a detection range of 0.0125-1128 µM and a limit of detection of 0.009 µM (S/N = 3). The sensing performance of N-GQDs@SnS2 was highly stable, selective, and reproducible. The practical application of the N-GQDs@SnS2 sensor was successfully demonstrated by quantifying H2O2 in lens cleaner, human urine, and saliva samples. Finally, the N-GQDs@SnS2 electrode was successfully applied for the real-time monitoring of H2O2 released from breast cancer cells and mouse fibroblasts. This study paves the way to designing efficient non-enzymatic electrochemical sensors for various biomolecule detection using a simple method.


Assuntos
Neoplasias da Mama , Grafite , Pontos Quânticos , Animais , Camundongos , Humanos , Feminino , Grafite/química , Pontos Quânticos/química , Peróxido de Hidrogênio , Eletrodos
14.
Nanoscale ; 14(39): 14789-14800, 2022 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-36184995

RESUMO

The poor permeability of therapeutic agents across the blood-brain barrier and blood-tumor barrier is a significant barrier in glioma treatment. Low-density lipoprotein receptor-related protein (LRP-1) recognises a dual-targeting ligand, angiopep-2, which is overexpressed in the BBB and gliomas. Here, we have synthesized Ti@FeAu core-shell nanoparticles conjugated with angiopep-2 (Ti@FeAu-Ang nanoparticles) to target glioma cells and treat brain cancer via hyperthermia produced by a magnetic field. Our results confirmed that Ti@FeAu core-shell nanoparticles were superparamagnetic, improved the negative contrast effect on glioma, and exhibited a temperature elevation of 12° C upon magnetic stimulation, which implies potential applications in magnetic resonance imaging (MRI) and hyperthermia-based cancer therapy. Angiopep-2-decorated nanoparticles exhibited higher cellular uptake by C6 glioma cells than by L929 fibroblasts, demonstrating selective glioma targeting and improved cytotoxicity up to 85% owing to hyperthermia produced by a magnetic field. The in vivo findings demonstrated that intravenous injection of Ti@FeAu-Ang nanoparticles exhibited a 10-fold decrement in tumor volume compared to the control group. Furthermore, immunohistochemical analysis of Ti@FeAu-Ang nanoparticles showed that coagulative necrosis of tumor tissues and preliminary safety analysis highlighted no toxicity to the haematological system, after Ti@FeAu-Ang nanoparticle-induced hyperthermia treatment.


Assuntos
Neoplasias Encefálicas , Glioma , Nanopartículas de Magnetita , Nanopartículas , Ligas , Barreira Hematoencefálica/metabolismo , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/terapia , Linhagem Celular Tumoral , Diagnóstico por Imagem , Sistemas de Liberação de Medicamentos/métodos , Glioma/tratamento farmacológico , Glioma/terapia , Humanos , Ligantes , Lipoproteínas LDL , Peptídeos , Nanomedicina Teranóstica , Titânio/farmacologia
15.
Nanomaterials (Basel) ; 12(2)2022 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-35055275

RESUMO

Hydrogen sulfide (H2S), an endogenous gasotransmitter, is produced in mammalian systems and is closely associated with pathological and physiological functions. Nevertheless, the complete conversion of H2S is still unpredictable owing to the limited number of sensors for accurate and quantitative detection of H2S in biological samples. In this study, we constructed a disposable electrochemical sensor based on PtNi alloy nanoparticles (PtNi NPs) for sensitive and specific in situ monitoring of H2S released by human breast cancer cells. PtNi alloy NPs with an average size of 5.6 nm were prepared by a simple hydrothermal approach. The conversion of different forms of sulfides (e.g., H2S, HS-, and S2-) under various physiological conditions hindered the direct detection of H2S in live cells. PtNi NPs catalyze the electrochemical oxidation of H2S in a neutral phosphate buffer (PB, pH 7.0). The PtNi-based sensing platform demonstrated a linear detection range of 0.013-1031 µM and the limit of detection was 0.004 µM (S/N = 3). Moreover, the PtNi sensor exhibited a sensitivity of 0.323 µA µM-1 cm-2. In addition, the stability, repeatability, reproducibility, and anti-interference ability of the PtNi sensor exhibited satisfactory results. The PtNi sensor was able to successfully quantify H2S in pond water, urine, and saliva samples. Finally, the biocompatible PtNi electrode was effectively employed for the real-time quantification of H2S released from breast cancer cells and mouse fibroblasts.

16.
Curr Opin Biotechnol ; 73: 355-363, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34735985

RESUMO

Breakthroughs in our understanding of the complex interplay between cellular nanoenvironment and biomolecular signalling pathways are facilitating development of targeted osteogenic platforms. As critical biomolecules for osteogenesis, growth factors stimulate osteogenesis by activating key genes and transcription factors. The first half of this review presents emerging interconnectedness and recent discoveries of osteogenic signalling pathways initiating from growth factors for example, bone morphogenetic protein 2 (BMP-2). To complement this, the second half of review proposes a number of strategies to induce osteogenesis which include metallic, organic implants, nanotopological environments as well as growth factor immobilization techniques. The drawbacks of traditional osteogenic implants and how these have been overcome by biomedical engineers in the recent years without producing side-effects have also been summarized.


Assuntos
Regeneração Óssea , Osteogênese , Diferenciação Celular , Osteogênese/genética , Transdução de Sinais
17.
Analyst ; 146(23): 7118-7125, 2021 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-34739011

RESUMO

In this study we investigated the synergistic effects of the chirality (molecular structure) and surface morphology (nanostructure) of a newly designed sensing platform for the stereoselective recognition of biomolecules. We synthesized 3,4-ethylenedioxythiophene monomers presenting an OH functional group on the side chain (EDOT-OH) with either R or S chirality and then electropolymerized them in a template-free manner to engineer poly(EDOT-OH) nanotubes and smooth films with R or S chirality. We used a quartz crystal microbalance (QCM) to examine the differential binding of fetal bovine serum, RGD peptide, insulin, and (R)- and (S)-mandelic acid (MA) on these chiral polymeric platforms. All of these biomolecules bound stereoselectively and with greater affinity toward the nanotubes than to the smooth films. The sensitive chiral recognition of (S)- and (R)-MA on the (R)-poly(EDOT-OH) nanotube surface occurred with the highest chiral discrepancy ratio of 1.80. In vitro experiments revealed a greater degree of protein deposition from MCF-7 cells on the chiral nanotube surfaces. We employed ab initio molecular dynamics simulations and density functional theory calculations to investigate the mechanism underlying the sensitive chiral recognition between the chiral sensing platforms and the chiral analyte molecules.


Assuntos
Biopolímeros , Compostos Bicíclicos Heterocíclicos com Pontes , Simulação por Computador , Técnicas de Microbalança de Cristal de Quartzo
18.
Nanomaterials (Basel) ; 11(8)2021 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-34443879

RESUMO

The interactions between cells and nanomaterials at the nanoscale play a pivotal role in controlling cellular behavior and ample evidence links cell intercommunication to nanomaterial size. However, little is known about the effect of nanomaterial geometry on cell behavior. To elucidate this and to extend the application in cancer theranostics, we have engineered core-shell cobalt-gold nanoparticles with spherical (Co@Au NPs) and elliptical morphology (Co@Au NEs). Our results show that owing to superparamagnetism, Co@Au NPs can generate hyperthermia upon magnetic field stimulation. In contrast, due to the geometric difference, Co@Au NEs can be optically excited to generate hyperthermia upon photostimulation and elevate the medium temperature to 45 °C. Both nanomaterial geometries can be employed as prospective contrast agents; however, at identical concentration, Co@Au NPs exhibited 4-fold higher cytotoxicity to L929 fibroblasts as compared to Co@Au NEs, confirming the effect of nanomaterial geometry on cell fate. Furthermore, photostimulation-generated hyperthermia prompted detachment of anti-cancer drug, Methotrexate (MTX), from Co@Au NEs-MTX complex and which triggered 90% decrease in SW620 colon carcinoma cell viability, confirming their application in cancer theranostics. The geometry-based perturbation of cell fate can have a profound impact on our understanding of interactions at nano-bio interface which can be exploited for engineering materials with optimized geometries for superior theranostic applications.

19.
Nanomaterials (Basel) ; 12(1)2021 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-35010011

RESUMO

Metastatic oral squamous cell carcinoma (SCC) displays a poor disease prognosis with a 5-year survival rate of 39%. Chemotherapy has emerged as the mainstream treatment against small clusters of cancer cells but poses more risks than benefits for metastatic cells due to the non-specificity and cytotoxicity. To overcome these obstacles, we conjugated antibodies specific for matrix metalloproteinase-1 (MMP-1), a prognostic biomarker of SCC, to iron-gold bimetallic nanoparticles (FeAu NPs) and explored the capability of this complex to target and limit SSC cell growth via magnetic field-induced hyperthermia. Our results showed that 4.32 ± 0.79 nm sized FeAu NPs were superparamagnetic in nature with a saturation magnetization (Ms) of 5.8 emu/g and elevated the media temperature to 45 °C, confirming the prospect to deliver hyperthermia. Furthermore, conjugation with MMP-1 antibodies resulted in a 3.07-fold higher uptake in HSC-3 (human tongue squamous cell carcinoma) cells as compared to L929 (fibroblast) cells, which translated to a 5-fold decrease in cell viability, confirming SCC targeting. Finally, upon magnetic stimulation, MMP-1-FeAu NPs conjugate triggered 89% HSC-3 cellular death, confirming the efficacy of antibody-conjugated nanoparticles in limiting SCC growth. The synergistic effect of biomarker-specific antibodies and magnetic nanoparticle-induced hyperthermia may open new doors towards SCC targeting for improved disease prognosis.

20.
Pharmaceutics ; 12(11)2020 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-33207577

RESUMO

The lack of optimal methods employing nanoparticles to administer local anesthesia often results in posing severe risks such as non-biocompatibility, in vivo cytotoxicity, and drug overdose to patients. Here, we employed magnetic field-induced hyperthermia to achieve localized anesthesia. We synthesized iron-gold alloy nanoparticles (FeAu Nps), conjugated an anesthetic drug, Lidocaine, and coated the product with gelatin to increase the biocompatibility, resulting in a FeAu@Gelatin-Lidocaine nano-complex formation. The biocompatibility of this drug-nanoparticle conjugate was evaluated in vitro, and its ability to trigger local anesthesia was also evaluated in vivo. Upon exposure to high-frequency induction waves (HFIW), 7.2 ± 2.8 nm sized superparamagnetic nanoparticles generated heat, which dissociated the gelatin coating, thereby triggering Lidocaine release. MTT assay revealed that 82% of cells were viable at 5 mg/mL concentration of Lidocaine, indicating that no significant cytotoxicity was induced. In vivo experiments revealed that unless stimulated with HFIW, Lidocaine was not released from the FeAu@Gelatin-Lidocaine complex. In a proof-of-concept experiment, an intramuscular injection of FeAu@Gelatin-Lidocaine complex was administered to the rat posterior leg, which upon HFIW stimulation triggered an anesthetic effect to the injected muscle. Based on our findings, the FeAu@Gelatin-Lidocaine complex can deliver hyperthermia-induced controlled anesthetic drug release and serve as an ideal candidate for site-specific anesthesia administration.

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