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1.
Sci Rep ; 12(1): 15431, 2022 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-36104466

RESUMO

In this study, the main focus was on designing and synthesizing a novel magnetic nanobiocomposite and its application in hyperthermia cancer treatment. Regarding this aim, sodium alginate (SA) hydrogel with CaCl2 cross-linker formed and modified by silk fibroin (SF) natural polymer and halloysite nanotubes (HNTs), followed by in situ Fe3O4 magnetic nanoparticles preparation. No important differences were detected in red blood cells (RBCs) hemolysis, confirming the high blood compatibility of the treated erythrocytes with this nanobiocomposite. Moreover, the synthesized SA hydrogel/SF/HNTs/Fe3O4 nanobiocomposite does not demonstrate toxicity toward HEK293T normal cell line after 48 and 72 h. The anticancer property of SA hydrogel/SF/HNTs/Fe3O4 nanobiocomposites against breast cancer cell lines was corroborated. The magnetic saturation of the mentioned magnetic nanobiocomposite was 15.96 emu g-1. The specific absorption rate (SAR) was measured to be 22.3 W g-1 by applying an alternating magnetic field (AMF). This novel nanobiocomposite could perform efficiently in the magnetic fluid hyperthermia process, according to the obtained results.


Assuntos
Fibroínas , Hipertermia Induzida , Nanocompostos , Nanotubos , Alginatos , Argila , Células HEK293 , Humanos , Hidrogéis , Fenômenos Magnéticos , Nanocompostos/uso terapêutico
2.
J Enzyme Inhib Med Chem ; 37(1): 2540-2550, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36120953

RESUMO

In this work, a highly effective separation approach mediated by 5-Lipoxygenase (5-LOX) was established for screening and isolation of anti-inflammatory ingredients from leaves of Lonicera japonica Thunb. (LLJT). Using 5-LOX immobilised on TiO2 nanotubes as a microreactor, the targeted screening was exploited by combining with HPLC-MS system. Four compounds confirmed as luteolin, luteoside, lonicerin, and isochlorogenic acid C and a fraction (M1) were screened out to be potent inhibitors of 5-LOX. Their anti-inflammatory activities were further investigated and confirmed by RAW 264.7 cells inflammation model and rat foot swelling model. Furthermore, M1 was prepared by MCI GEL CHP20P column chromatography, and further separated by Pre-HPLC. One new compound confirmed to be 5,7,3',4'-tetrahydroxyflavone-7-O-sambubioside was first isolated from LLJT. The results provide a new method for the effective separation of active components derived from natural products.HighlightsA 5-LOX mediated separation method was established for isolation of anti-inflammatory compounds.An anti-inflammatory ingredient was separated by MCI GEL CHP20P column chromatography.One new compound was first isolated from leaves of Lonicera japonica Thunb.5-LOX was immobilised on TiO2 nanotubes and exploited by combining with HPLC-MS system.The anti-inflammatory activity of screened components was evaluated. [Figure: see text].


Assuntos
Lonicera , Nanotubos , Animais , Anti-Inflamatórios/farmacologia , Araquidonato 5-Lipoxigenase , Lonicera/química , Luteolina , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Ratos , Titânio
3.
J Mater Sci Mater Med ; 33(9): 63, 2022 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-36065035

RESUMO

Current evidence has suggested that diabetes increases the risk of implanting failure, and therefore, appropriate surface modification of dental implants in patients with diabetes is crucial. TiO2 nanotube (TNT) has an osteogenic nanotopography, and its osteogenic properties can be further improved by loading appropriate drugs. Cinnamaldehyde (CIN) has been proven to have osteogenic, anti-inflammatory, and anti-bacterial effects. We fabricated a pH-responsive cinnamaldehyde-TiO2 nanotube coating (TNT-CIN) and hypothesized that this coating will exert osteogenic, anti-inflammatory, and anti-bacterial functions in a simulated diabetes condition. TNT-CIN was constructed by anodic oxidation, hydroxylation, silylation, and Schiff base reaction to bind CIN, and its surface characteristics were determined. Conditions of diabetes and diabetes with a concurrent infection were simulated using 22-mM glucose without and with 1-µg/mL lipopolysaccharide, respectively. The viability and osteogenic differentiation of bone marrow mesenchymal stem cells, polarization and secretion of macrophages, and resistance to Porphyromonas gingivalis and Streptococcus mutans were evaluated. CIN was bound to the TNT surface successfully and released better in low pH condition. TNT-CIN showed better osteogenic and anti-inflammatory effects and superior bacterial resistance than TNT in a simulated diabetes condition. These findings indicated that TNT-CIN is a promising, multifunctional surface coating for patients with diabetes needing dental implants. Graphical abstract.


Assuntos
Implantes Dentários , Diabetes Mellitus , Nanotubos , Acroleína/análogos & derivados , Anti-Inflamatórios/farmacologia , Humanos , Concentração de Íons de Hidrogênio , Nanotubos/química , Osteogênese , Propriedades de Superfície , Titânio
4.
J Nanobiotechnology ; 20(1): 406, 2022 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-36076230

RESUMO

Nanofabrication technologies have been recently applied to the development of engineered nano-bio interfaces for manipulating complex cellular processes. In particular, vertically configurated nanostructures such as nanoneedles (NNs) have been adopted for a variety of biological applications such as mechanotransduction, biosensing, and intracellular delivery. Despite their success in delivering a diverse range of biomolecules into cells, the mechanisms for NN-mediated cargo transport remain to be elucidated. Recent studies have suggested that cytoskeletal elements are involved in generating a tight and functional cell-NN interface that can influence cargo delivery. In this study, by inhibiting actin dynamics using two drugs-cytochalasin D (Cyto D) and jasplakinolide (Jas), we demonstrate that the actin cytoskeleton plays an important role in mRNA delivery mediated by silicon nanotubes (SiNTs). Specifically, actin inhibition 12 h before SiNT-cellular interfacing (pre-interface treatment) significantly dampens mRNA delivery (with efficiencies dropping to 17.2% for Cyto D and 33.1% for Jas) into mouse fibroblast GPE86 cells, compared to that of untreated controls (86.9%). However, actin inhibition initiated 2 h after the establishment of GPE86 cell-SiNT interface (post-interface treatment), has negligible impact on mRNA transfection, maintaining > 80% efficiency for both Cyto D and Jas treatment groups. The results contribute to understanding potential mechanisms involved in NN-mediated intracellular delivery, providing insights into strategic design of cell-nano interfacing under temporal control for improved effectiveness.


Assuntos
Actinas , Nanotubos , Citoesqueleto de Actina/metabolismo , Actinas/metabolismo , Animais , Citocalasina D/farmacologia , Mecanotransdução Celular , Camundongos , RNA Mensageiro , Silício/química
5.
J Vis Exp ; (186)2022 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-36121261

RESUMO

Recent discoveries have revealed that cells perform direct, long-range, intercellular transfer via nano-scale, actin-membrane conduits, namely "tunneling nanotubes" (TNTs). TNTs are defined as open-ended, lipid bilayer-encircled membrane extensions that mediate continuity between neighboring cells of diameters ranging between 50 nm and 1 µm. TNTs were demonstrated initially in neuronal cells, but successive studies have revealed the existence of TNTs in several cell types and diseases, such as neurodegenerative diseases, viral infections, and cancer. Several studies have referred to close-ended, electrically coupled membrane nanostructures between neighboring cells as TNTs or TNT-like structures. The elucidation of ultrastructure in terms of membrane continuity at the endpoint is technically challenging. In addition, studies on cell-cell communication are challenging in terms of the characterization of TNTs using conventional methods due to the lack of specific markers. TNTs are primarily defined as F-actin-based, open-ended membrane protrusions. However, one major limitation is that F-actin is present in all types of protrusions, making it challenging to differentiate TNTs from other protrusions. One of the notable characteristics of F-actin-based TNTs is that these structures hover between two cells without touching the substratum. Therefore, distinct F-actin-stained TNTs can conveniently be distinguished from other protrusions such as filopodia and neurites based on their hovering between cells. We have recently shown that the internalization of oligomeric amyloid-ß1-42 (oAß) via actin-dependent endocytosis stimulates activated p21-activated kinase-1 (PAK1), which mediates the formation of F-actin-containing TNTs coexpressed with phospho-PAK1 between SH-SY5Y neuronal cells. This protocol outlines a 3D volume analysis method to identify and characterize TNTs from the captured z-stack images of F-actin- and phospho-PAK1-immunostained membrane protrusions in oAß-treated neuronal cells. Further, TNTs are distinguished from developing neurites and neuronal outgrowths based on F-actin- and ß-III tubulin-immunostained membrane conduits.


Assuntos
Nanotubos , Neuroblastoma , Actinas/metabolismo , Humanos , Bicamadas Lipídicas , Nanotubos/química , Tubulina (Proteína) , Quinases Ativadas por p21
6.
Int J Mol Sci ; 23(17)2022 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-36076945

RESUMO

We investigated the effects of the crystalline state for seed layers (SLs) on the growth morphology and material characteristics for hydrothermally grown ZnO nanorods (NRs). For this, preheating (PH) at different temperatures (100-300 °C) and O2 plasma treatment (PT) for 9 min were performed during the growth of SLs on p-Si by the aqueous solution-based method to provide the characteristic change on the NR growth platform. An improvement in material properties was achieved from the ZnO NRs grown on the SL crystals of enhanced crystalline quality in terms of the increased preferred orientation (002), the higher UV emission with suppressed deep-level emissions, the recovery of O/Zn stoichiometry, and the reduction of various intrinsic defects. Ultraviolet photodiodes of a p-Si/n-ZnO-NR structure fabricated under the SL conditions of O2 PT and PH at 100 °C showed a significantly enhanced on-off current ratio of ~90 at +5 V and faster photoresponse characteristics presenting a reduction in the fall time from 16 to 9 s.


Assuntos
Nanotubos , Óxido de Zinco , Nanotubos/química , Sementes , Água/química , Óxido de Zinco/química
7.
Int J Mol Sci ; 23(17)2022 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-36077154

RESUMO

The paper reports a strategy to synthesize Cd0.9Co0.1S nanorods (NRs) via a one-pot solvothermal method. Remarkably, the pencil-shaped Cd0.9Co0.1S NRs with a large aspect ratio and good polycrystalline plane structure significantly shorten the photogenerated carrier transfer path and achieve fast separation. An appropriate amount of Co addition enhances visible light-harvesting and generates a photothermal effect to improve the surface reaction kinetics and increases the charge transfer rate. Moreover, the internal electric field facilitates the separation and transfer of carriers and effectively impedes their recombination. As a result, the optimized Cd0.9Co0.1S NRs yield a remarkable H2 evolution rate of 8.009 mmol·g-1·h-1, which is approximately 7.2 times higher than that of pristine CdS. This work improves the photocatalytic hydrogen production rate by tuning and optimizing electronic structures through element addition and using the photothermal synergistic effect.


Assuntos
Compostos de Cádmio , Nanotubos , Cádmio , Compostos de Cádmio/química , Eletricidade , Luz , Nanotubos/química
8.
ACS Appl Mater Interfaces ; 14(36): 40513-40521, 2022 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-36049895

RESUMO

Rh is a noble metal introduced in bioapplications, including diagnosis and therapy, in addition to its consolidated utilization in organic catalysis and electrocatalysis. Herein, we designed the synthesis of highly crystalline Rh nanocrystal-decorated Rh-Te nanorods (RhTeNRs) through galvanic replacement of sacrificial Te nanorod (TeNR) templates and subsequent polyol regrowth. The obtained RhTeNRs showed excellent colloidal stability and efficient heat dissipation and photocatalytic activity under various laser irradiation wavelengths. Based on the confirmed biocompatibility, RhTeNRs were introduced into in vitro and in vivo cancer phototherapies. The results confirmed the selective physical death of cancer cells in the local area through laser irradiation. While chemotherapy does not guarantee successful treatment due to side effects and resistance, phototherapy using heat and reactive oxygen species generation of RhTeNRs induces physical death.


Assuntos
Nanotubos , Neoplasias , Ródio , Animais , Camundongos , Camundongos Endogâmicos BALB C , Nanotubos/química , Neoplasias/terapia , Fototerapia , Polímeros , Telúrio
9.
ACS Appl Mater Interfaces ; 14(36): 40612-40623, 2022 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-36053499

RESUMO

Cancer immunotherapy has achieved considerable clinical progress in recent years on account of its potential to treat metastatic tumors and inhibit recurrence. However, low patient response rates and dose-limiting toxicity are the major limitations of immunotherapy. Nanoparticle-based photothermal immunotherapy can amplify antitumor immune responses, although poor tumor penetration depth of near-infrared radiation (NIR) and the immunosuppressive tumor microenvironment significantly dampen its effects. We designed a nanoplatform based on gold nanorods for NIR-II-mediated photothermal therapy (PTT) combined with N6-methyladenosine (m6A) demethylase inhibition to achieve enhanced photothermal immunotherapy against prostate cancer. The GNRs were assembled layer by layer with polystyrenesulfonate as the interconnecting layer and then coated with a cationic polymer of γ-cyclodextrin (CD)-cross-linked low-molecular-weight polyethylenimine that was conjugated to an 8-mer peptide targeting the prostate tumor-specific gastrin-releasing peptide receptor. The m6A RNA demethylase inhibitor meclofenamic acid (MA) was then loaded into the CD cavity through hydrophobic interactions. GNR-CDP8MA specifically targeted the prostate tumor cells and selectively accumulated at the tumor site in vivo. In addition, GNR-CDP8MA almost completely ablated prostate cancer cell-derived tumors upon 1208 nm laser irradiation. Mechanistically, NIR-II triggered the release of MA from GNR-CDP8MA, which increased global mRNA m6A methylation and decreased the stability of PDL1 transcripts. Furthermore, GNR-CDP8MA-mediated PTT-induced immunogenic cell death in the primary tumor and consequently enhanced antitumor immunity by activating the antigen-presenting dendritic cells and tumor-specific effector T cells in the metastatic tumors. This study offers insights into synergistic m6A RNA methylation and PTT as an effective strategy for cancer immunotherapy.


Assuntos
Ciclodextrinas , Nanotubos , Neoplasias da Próstata , Adenosina/análogos & derivados , Linhagem Celular Tumoral , Ouro/química , Ouro/farmacologia , Humanos , Imunoterapia , Masculino , Ácido Meclofenâmico , Nanotubos/química , Fototerapia , Neoplasias da Próstata/tratamento farmacológico , RNA , Microambiente Tumoral
10.
Biomacromolecules ; 23(9): 3866-3874, 2022 09 12.
Artigo em Inglês | MEDLINE | ID: mdl-35977724

RESUMO

Gold nanorods (GNRs) are widely used in various biomedical applications such as disease imaging and therapy due to their unique plasmonic properties. To improve their bioavailability, GNRs often need to be coated with hydrophilic polymers so as to impart stealth properties. Poly(ethylene glycol) (PEG) has been long used as such a coating material for GNRs. However, there is increasing acknowledgement that the amphiphilic nature of PEG facilitates its interaction with protein molecules, leading to immune recognition and consequent side effects. This has motivated the search for new classes of low-fouling polymers with high hydrophilicity as alternative low-fouling surface coating materials for GNRs. Herein, we report the synthesis, characterization, and application of GNRs coated with highly hydrophilic sulfoxide-containing polymers. We investigated the effect of the sulfoxide polymer coating on the cellular uptake and in vivo circulation time of the GNRs and compared these properties with pegylated GNR counterparts. The photothermal effect and photoacoustic imaging of these polymer-coated GNRs were also explored, and the results show that these GNRs are promising as nanotheranostic particles for the treatment of cancer.


Assuntos
Ouro , Nanotubos , Ouro/farmacologia , Polímeros , Medicina de Precisão , Sulfóxidos
11.
Biosens Bioelectron ; 216: 114629, 2022 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-36001932

RESUMO

Iridium(III) complexes have been developed as eminent electrochemiluminescence (ECL) luminophores, but their current applications are only limited to anodic ECL emission because of weak cathodic ECL emission. This work explored poly(styrene-co-maleicanhydride) (PSMA) as functional reagent to modulate iridium(III) complexes to simultaneously emit bipolar ECL signals. The prepared iridium(III) nanorods (Ir NRs) were detected strong bipolar ECL emissions at +0.9 V and -2.0 V with N,N-diisopropylethylenediamine (DPEA) and persulfate (S2O82-) as coreactant, respectively. Meanwhile, Ag nanoparticles (Ag NPs) were developed as dual-regulating coreaction accelerator to boost the bipolar emissions of Ir NRs simultaneously. The dual-emitting Ir NRs coupled with dual-regulating coreaction accelerator Ag NPs facilitated the construction of mono-luminophore-based ECL ratio strategy for detecting amyloid-ß oligomers (AßO). When the target AßO appeared, the Mg2+-dependent DNAzyme-powered biped walkers were unlocked to cleave single-stranded S1 immobilized on the surface of magnetic beads (MBs), resulting in the production of massive single-stranded ST. Then, the output ST cleaved hairpin H1 captured by Ir NRs modified electrode to produce numerous single strands, which could initiate the hybridization chain reaction (HCR) between Ag NPs-labeled H2 and Ag NPs-labeled H3 to introduce abundant Ag NPs onto the electrode surface. Due to the enhancement effect of Ag NPs on the bipolar ECL emissions from Ir NRs, the ECL ratio detection of AßO was achieved with the detection limit of 0.62 pM. The unique dual-emitting properties of Ir NRs coupled with dual-regulating effect of Ag NPs provided an interesting mono-luminophore-based ECL ratio sensing platform for biological analysis.


Assuntos
Técnicas Biossensoriais , DNA Catalítico , Nanopartículas Metálicas , Nanotubos , Peptídeos beta-Amiloides , Técnicas Biossensoriais/métodos , Técnicas Eletroquímicas/métodos , Irídio , Limite de Detecção , Medições Luminescentes/métodos , Prata , Estirenos
12.
Int J Mol Sci ; 23(15)2022 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-35955856

RESUMO

Surface topography, protein adsorption, and the loading of coating materials can affect soft tissue sealing. Graphene oxide (GO) is a promising candidate for improving material surface functionalization to facilitate soft tissue integration between cells and biomaterials. In this study, TiO2 nanotubes (TNTs) were prepared by the anodization of Ti, and TNT-graphene oxide composites (TNT-GO) were prepared by subsequent electroplating. The aim of this study was to investigate the effect of TNTs and TNT-GO surface modifications on the behavior of human gingival fibroblasts (HGFs). Commercially pure Ti and TNTs were used as the control group, and the TNT-GO surface was used as the experimental group. Scanning electron microscopy, X-ray photoelectron spectroscopy, and X-ray diffraction were used to perform sample characterization. Cell adhesion, cell proliferation, cell immunofluorescence staining, a wound-healing assay, real-time reverse-transcriptase polymerase chain reaction (RT-PCR), and Western blotting showed that the proliferation, adhesion, migration, and adhesion-related relative gene expression of HGFs on TNT-GO were significantly enhanced compared to the control groups, which may be mediated by the activation of integrin ß1 and the MAPK-Erk1/2 pathway. Our findings suggest that the biological reactivity of HGFs can be enhanced by the TNT-GO surface, thereby improving the soft tissue sealing ability.


Assuntos
Nanotubos , Titânio , Adesão Celular , Proliferação de Células , Fibroblastos/metabolismo , Grafite , Humanos , Nanotubos/química , Propriedades de Superfície , Titânio/química
13.
J Environ Manage ; 318: 115515, 2022 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-35949077

RESUMO

The purpose of this study was to evaluate the performance of synthesized TiO2 nanotube arrays (NTAs) for the removal of the COVID-19 aided antibiotic ciprofloxacin (CIP) and the textile dye methylene blue (MB) from model wastewater. Synthesis of TiO2 NTAs showed that anodization potential and calcination temperatures directly influence nanotube formation. The increased anodization potential from 10 to 40 V resulted in the development of larger porous nanotubes with a diameter of 36-170 nm, while the collapse of the tubular structure was registered at the highest applied potential. Furthermore, it was found that the 500 °C calcination temperature was the most prominent for the formation of the most photocatalytically active TiO2 NTAs, due to the optimal anatase/rutile ratio of 4.60. The degradation of both model compounds was achieved with all synthesized TiO2 NTAs; however, the most photocatalytically active NTA sample was produced at 30 V and 500 °C. Compared to photocatalysis, CIP degradation was greatly enhanced by 5-25 times when ozone was introduced to the photocatalytic cell (rates 0.4-4.2 × 10-1 min-1 versus 0.07-0.2 × 10-1 min-1). This resulted in the formation of CIP degradation by-products, with different mass-to-charge ratios from [M+H]+ 346 to 273 m/z. Even though the CIP degradation pathway is rather complex, three main mechanisms, decarboxylation, hydroxylation reaction, and piperazine ring cleavage, were proposed and explained. Furthermore, treated samples were placed in contact with the crustaceans Daphnia magna. It was found that 100% mortality was achieved when approximately 60% of the remaining TOC was present in the samples, indicating that toxic degradation by-products were formed.


Assuntos
COVID-19 , Nanotubos , Ozônio , Antibacterianos/análise , Ciprofloxacina , Humanos , Nanotubos/química , Titânio/química , Água
14.
J Nanobiotechnology ; 20(1): 391, 2022 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-36045404

RESUMO

BACKGROUND: Cancer nanomedicines based on synthetic polypeptides have attracted much attention due to their superior biocompatibility and biodegradability, stimuli responsive capability through secondary conformation change, adjustable functionalities for various cargos such as peptides, proteins, nucleic acids and small therapeutic molecules. Recently, a few nanoformulations based on polypeptides comprising NK105, NC6004, NK911, CT2103, have entered phase I-III clinical trials for advanced solid tumors therapy. In the current study, we prepared polypeptide-based vesicles called peptosome via self-assembly of amphiphilic polypeptide-based PEG-PBLG diblock copolymer. RESULTS: In this regard, poly(γ-benzyl L-glutamate (PBLG) was synthesized via ring opening polymerization (ROP) of γ-benzyl L-glutamate-N-carboxyanhydride (BLG-NCA) using N-hexylamine as initiator. Then amine-terminated PBLG was covalently conjugated to heterofuctional maleimide PEG-carboxylic acid or methyl-PEG-carboxylic acid. The PEG-PBLG peptosomes were prepared through double emulsion method for the co-delivery of doxorubicin.HCl and gold nanorods as hydrophilic and hydrophobic agents in interior compartment and membrane of peptosomes, respectively (Pep@MUA.GNR-DOX) that DOX encapsulation efficiency and loading capacity were determined 42 ± 3.6 and 1.68 ± 3.6. Then, theranostic peptosomes were decorated with thiol-functionalized EpCAM aptamer throught thiol-maleimide reaction producing Apt-Pep@MUA.GNR-DOX for targeted delivery. The non-targeted and targeted peptosomes showed 165.5 ± 1.1 and 185 ± 4.7 nm diameters, respectively while providing sustained, controlled release of DOX. Furthermore, non-targeted and targeted peptosomes showed considerable serum stability. In vitro study on MCF-7 and 4T1 cells showed significantly higher cytotoxicity for Apt-Pep@MUA.GNR-DOX in comparison with Pep@MUA.GNR-DOX while both system did not show any difference in cytotoxicity against CHO cell line. Furthermore, Apt-Pep@MUA.GNR-DOX illustrated higher cellular uptake toward EpCAM-overexpressing 4T1 cells compared to Pep@MUA.GNR-DOX. In preclinical stage, therapeutic and diagnostic capability of the prepared Pep@MUA.GNR-DOX and Apt-Pep@MUA.GNR-DOX were investigated implementing subcutaneous 4T1 tumor model in BALB/c mice. The obtained data indicated highest therapeutic index for Apt-Pep@MUA.GNR-DOX compared to Pep@MUA.GNR-DOX and free DOX. Moreover, the prepared system showed capability of CT imaging of tumor tissue in 4T1 tumorized mice through tumor accumulation even 24 h post-administration. CONCLUSION: In this regard, the synthesized theranostic peptosomes offer innovative hybrid multipurpose platform for fighting against breast cancer.


Assuntos
Nanotubos , Neoplasias , Animais , Ácidos Carboxílicos , Linhagem Celular Tumoral , Doxorrubicina , Sistemas de Liberação de Medicamentos/métodos , Molécula de Adesão da Célula Epitelial , Ácido Glutâmico , Ouro/química , Maleimidas , Camundongos , Nanotubos/química , Neoplasias/tratamento farmacológico , Peptídeos/química , Polietilenoglicóis/química , Compostos de Sulfidrila , Tomografia Computadorizada por Raios X
15.
J Phys Chem Lett ; 13(31): 7355-7362, 2022 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-35924826

RESUMO

Dimethyl-2,5-bis[4-(methoxyphenyl)amino] terephthalate (DBMPT) exhibits aggregation-induced enhancement of emission with Tween 40 and formation of nanorods with strong orange fluorescence. These nanorods disrupt fibrils of human serum albumin and lead to partial refolding of the protein, as monitored by circular dichroism and thioflavin T (ThT) fluorescence. The resultant milieu emits white light, the mechanism of which is explored in this study. It is established that direct excitation of the acceptor plays a significant role, even though Förster resonance energy transfer (FRET) is found to be operative to some extent. A decrease in the fluorescence intensity and lifetime of ThT with progressive addition of DBMPT, which is often used as the sole indicator of FRET, is ascribed to the disruption of the fibrils by the nanorods.


Assuntos
Amiloide , Nanotubos , Amiloide/metabolismo , Dicroísmo Circular , Humanos , Albumina Sérica Humana , Tensoativos
16.
Environ Res ; 214(Pt 4): 113972, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35952744

RESUMO

Efficient removal of low-concentration ammonia from chlorinated wastewater is a challenge for decentralized wastewater treatment due to its notorious environmental effect and lethal influence on aquaculture. Photoelectrocatalytic (PEC) oxidation process is considered as an efficient and environment-friendly approach, whereas a low-cost and stable photoanode is crucial. In this study, TiO2 nanotubes (TNTs) photoanode (Ar-TNT-500 °C) with excellent physicochemical and photoelectrochemical properties was prepared by optimizing the parameters of anodization, including the voltage/times of anodization and the atmosphere/temperature of heat treatment. During the synthesis, the electrochemical and heat treatment processes promoted the formation of oxygen vacancies (OV) on the TNTs surface and enhanced its electrocatalytic activity. The optimized Ar-TNT-500 °C photoanode could selectively convert ammonia to N2 (86%) and a small amount of nitrate (14%). Radical quenching and probe experiments confirmed that the ClO produced by rapid quenching of OH and Cl by free chlorine dominated the selective degradation of ammonia in the synergistic process of photocatalysis and electrocatalysis. The cycle of chlorine-based radicals (ClO and Cl) and Cl- provided a continuous and efficient ammonia oxidation system, because chlorine-based radicals could efficiently and selectively oxidize ammonia and reduce the production of toxic (per) chlorate.


Assuntos
Amônia , Nanotubos , Amônia/química , Cloro/química , Nanotubos/química , Titânio , Águas Residuárias
17.
Dalton Trans ; 51(36): 13646-13656, 2022 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-36040135

RESUMO

Excessive drug usage and sewage discharges containing antibiotics have caused water contamination due to the rapid growth of pharmaceutical industries. Tetracycline (TC) is one of the most frequently applied antibiotics having a significant impact on the aquatic environment, water quality and human health and thus effective approaches for TC removal from water are urgently needed. Here, we have fabricated P-doped CdS (CdS-P0.8) nanorods (NRs) by one-step thermal phosphorization treatment for TC degradation through photocatalytic reaction in the presence of blue and white LED light irradiation. Synthesized photocatalysts were characterized to authenticate the incorporation of P atoms on the CdS NR surface using XPS, XRD, ICP-OES and EDX mapping analyses. CdS-P0.8 NRs have greater photocatalytic activity for tetracycline degradation under blue LED light irradiation. TC degradation on CdS-P0.8 NRs followed pseudo-first order kinetics for both LED light sources. In the presence of blue LED light at an intensity of 10 mW cm-2, TC degradation efficiency and pseudo-first order rate constants of CdS-P0.8 NRs for the photocatalytic degradation reaction reached 95.4% and 0.13396 min-1 in 20 minutes without any supplemental oxygen sources. Scavenging experiments demonstrate that reactive oxygen species are produced during the photocatalytic degradation of tetracycline. As a result, due to the extensive utilization of photogenerated oxidative species such as h+, O2˙- and OH˙, CdS-P0.8 NRs demonstrated high photocatalytic tetracycline degradation efficiency in 20 minutes. Our findings shed more light on nonmetal P doping on CdS materials and other semiconductors, exploring new possibilities for photocatalytic degradation to efficiently reduce the amount and toxicity of TC antibiotics in wastewater.


Assuntos
Poluentes Ambientais , Nanotubos , Antibacterianos , Catálise , Humanos , Luz , Oxigênio , Espécies Reativas de Oxigênio , Esgotos , Tetraciclina , Águas Residuárias
18.
Nat Commun ; 13(1): 4551, 2022 08 05.
Artigo em Inglês | MEDLINE | ID: mdl-35931687

RESUMO

Peptidomimetic polymers have attracted increasing interest because of the advantages of facile synthesis, high molecular tunability, resistance to degradation, and low immunogenicity. However, the presence of non-native linkages compromises their ability to form higher ordered structures and protein-inspired functions. Here we report a class of amino acid-constructed polyureas with molecular weight- and solvent-dependent helical and sheet-like conformations as well as green fluorescent protein-mimic autofluorescence with aggregation-induced emission characteristics. The copolymers self-assemble into vesicles and nanotubes and exhibit H-bonding-mediated metamorphosis and discoloration behaviors. We show that these polymeric vehicles with ultrahigh stability, superfast responsivity and conformation-assisted cell internalization efficiency could act as an "on-off" switchable nanocarrier for specific intracellular drug delivery and effective cancer theranosis in vitro and in vivo. This work provides insights into the folding and hierarchical assembly of biomacromolecules, and a new generation of bioresponsive polymers and nonconventional luminescent aliphatic materials for diverse applications.


Assuntos
Nanotubos , Polímeros , Sistemas de Liberação de Medicamentos , Conformação Molecular , Nanotubos/química , Polímeros/química
19.
Spectrochim Acta A Mol Biomol Spectrosc ; 282: 121714, 2022 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-35940070

RESUMO

In this paper, the fluorescence quenching characteristics of Au-Ag-Pt core-shell nanorods have been studied.Due to nonradiative energy transformation, the fluorescence emission intensity of bovine serum albumin (BSA) could be greatly quenched.It has been found that the quenching effect of Au-Ag-Pt core-shell nanorods could be optimized by adjusting the concentration of chloroplatinic acid.Based on the fluorescence quenching properties of Au-Ag-Pt core-shell nanorods, Au-Ag-Pt trimetal fluorescence quenching nanoprobe has been prepared, and the specificity of alpha-fetoprotein (AFP) detection has also been realized.In order to guarantee the sensing specificity, the surface modification including carboxyl replacement, carboxyl activation and antibody connection have been performed on Au-Ag-Pt core-shell nanorods.By using the principle of specific combination of antigen and antibody, the specific detection of AFP has been realized with a lower detection limit of 4.0 pg/mL, and the linear detection range spans a scope from 0.03 to 0.5 ng/mL.Interference experiments and the actual samples detection results show that the Au-Ag-Pt trimetal core-shell nanorod probes have good anti-interference and repeatability.


Assuntos
Nanotubos , alfa-Fetoproteínas , Fluorescência , Ouro , Prata
20.
Sci Rep ; 12(1): 14751, 2022 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-36042364

RESUMO

Green synthesis selenium nanorods (Se-NRs) were produced based on Aloe vera leaf extract. The size, morphology, antimicrobial, and activation of Se-NRs for probiotics were analyzed. The Se-NRS was stable with a diameter of 12 and 40 nm, had an antimicrobial effect, and improved probiotics counts. The microcapsules loaded with Green Se-NRS (0, 0.05 or 0.1 mg/100 ml) and probiotics (Bifidobacterium lactis and Lactobacillus rhamnosus) were designated with efficiency between 95.25 and 97.27% and irregular shapes. Microcapsules were saved probiotics against gastrointestinal juices. The microcapsules were showed a minor inhibition effect against the cell line. Also, microcapsules integrated into stirred yogurt and exanimated for microbiology, chemically, and sensory for 30 days. The probiotics counts, acidity, total solids, and ash values of samples were increased during storage periods without affecting fat and protein contents. The overall acceptability of yogurt with microcapsules containing probiotics and Se-NRs was high without change in body, odor, color, and appearance.


Assuntos
Anti-Infecciosos , Nanotubos , Probióticos , Selênio , Cápsulas , Iogurte/microbiologia
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