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BACKGROUND & AIMS: Cholemic nephropathy (CN) is a severe complication of cholestatic liver diseases for which there is no specific treatment. We revisited its pathophysiology with the aim of identifying novel therapeutic strategies. METHODS: Cholestasis was induced by bile duct ligation (BDL) in mice. Bile flux in kidneys and livers was visualized by intravital imaging, supported by MALDI mass spectrometry imaging and liquid chromatography-tandem mass spectrometry. The effect of AS0369, a systemically bioavailable apical sodium-dependent bile acid transporter (ASBT) inhibitor, was evaluated by intravital imaging, RNA-sequencing, histological, blood, and urine analyses. Translational relevance was assessed in kidney biopsies from patients with CN, mice with a humanized bile acid (BA) spectrum, and via analysis of serum BAs and KIM-1 (kidney injury molecule 1) in patients with liver disease and hyperbilirubinemia. RESULTS: Proximal tubular epithelial cells (TECs) reabsorbed and enriched BAs, leading to oxidative stress and death of proximal TECs, casts in distal tubules and collecting ducts, peritubular capillary leakiness, and glomerular cysts. Renal ASBT inhibition by AS0369 blocked BA uptake into TECs and prevented kidney injury up to 6 weeks after BDL. Similar results were obtained in mice with humanized BA composition. In patients with advanced liver disease, serum BAs were the main determinant of KIM-1 levels. ASBT expression in TECs was preserved in biopsies from patients with CN, further highlighting the translational potential of targeting ASBT to treat CN. CONCLUSIONS: BA enrichment in proximal TECs followed by oxidative stress and cell death is a key early event in CN. Inhibiting renal ASBT and consequently BA enrichment in TECs prevents CN and systemically decreases BA concentrations. IMPACT AND IMPLICATIONS: Cholemic nephropathy (CN) is a severe complication of cholestasis and an unmet clinical need. We demonstrate that CN is triggered by the renal accumulation of bile acids (BAs) that are considerably increased in the systemic blood. Specifically, the proximal tubular epithelial cells of the kidney take up BAs via the apical sodium-dependent bile acid transporter (ASBT). We developed a therapeutic compound that blocks ASBT in the kidneys, prevents BA overload in tubular epithelial cells, and almost completely abolished all disease hallmarks in a CN mouse model. Renal ASBT inhibition represents a potential therapeutic strategy for patients with CN.
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Proteínas de Transporte , Colestase , Nefropatias , Hepatopatias , Glicoproteínas de Membrana , Transportadores de Ânions Orgânicos Dependentes de Sódio , Simportadores , Humanos , Camundongos , Animais , Colestase/complicações , Colestase/metabolismo , Rim/metabolismo , Simportadores/metabolismo , Ácidos e Sais Biliares/metabolismo , Fígado/metabolismo , Ductos Biliares/metabolismo , Hepatopatias/metabolismo , SódioRESUMO
Cosmeceuticals are a branch of cosmetic products that forms a bridge between cosmetic and drug products. It is a fast-growing branch of the cosmetic industry, especially after the introduction of novel formulation and manufacturing techniques such as lipid nanoparticles (LNPs). These LNPs-based cosmeceutical products offer several advantages such as enhanced bioavailability of cosmeceutical active ingredients (CAIs), improved aesthetic appeal, and stability of the final products. However, the use of these LNPs may raise some concerns about possible side effects of these LNPs and potential hazards to the customer's health. Accordingly, an update that focuses on the use of this important branch of nanoparticles is necessary since most review papers are dealing with all types of nanocarriers in the same review with little focus on LNPs. Therefore, in the current review, a detailed analysis of the advantages and disadvantages of LNPs in this field was highlighted, to emphasize the LNPs-based cosmeceuticals on the market, as well as the potential risk posed by LNPs on exposure and recently introduced regulatory guidelines to address them. In addition, if these products can be a candidate as products that meet the sustainable development goals raised by the UN are discussed.
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Chemotherapy is a mainstay strategy in the management of cancer. Regrettably, current chemotherapeutic agents are cytotoxic not only to cancer cells but also to healthy cells, resulting in dose-limiting serious side effects. Therefore, many researchers are eager to develop new drug delivery systems that may help to decrease the side effects and the target delivery of chemotherapy to cancer cells. One of the epochal drug delivery systems in this field is based on carbon nanotubes technology. The aim of this work is the dual covalent functionalization of single-walled carbon nanotubes (SWCNTs) with doxorubicin (DOX) connected with acid-labile linkage and mannose (Man) as a targeting agent. The characterization of the developed nano-drug by transmission electron microscopy showed good dispersibility of the functionalized SWCNTs with diameters (6-10) nm. Moreover, the percentage of functionalization was determined by thermogravimetric analysis showing 25% of functionalization in the case of SWNCTs-NHN-DOX (7) and 51% for SWCNTs-Man-NHN-DOX (11). The in vitro release profile of Dox from SWNCTs-NHN-DOX (7) showed 45% of the loaded drug was released over 18 h at pH 7.4 and almost complete release at pH 6.4 at 37 °C. However, the in vitro release profile of Dox from SWCNTs-Man-NHN-DOX (11) showed 75% of the loaded drug was released over 5 h at pH 6.4 at 37 °C. The cytotoxic effect of the compounds was studied on liver cancer cells (HepG2) at different concentrations and different pH conditions and was compared with DOX alone. The cytotoxicity of compounds SWCNTs-NHN-DOX (7) and SWCNTs-Man-NHN-DOX (11) was enhanced at pH 6.5, where the cell viability in both test compounds was significantly reduced by almost 50% compared to the cell viability at pH 7.4 for the same test compound Moreover, the pre-incubation of cells with different concentrations of mannose reduced the cytotoxicity of compound (11) by more than 50%, suggesting that the entry of this complex could be at least in part facilitated by mannose receptors, which imparts this complex a kind of selectivity for cancer cells that overexpress this type of receptors.
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Antineoplásicos , Portadores de Fármacos , Nanotubos de Carbono/química , Antineoplásicos/química , Antineoplásicos/farmacocinética , Antineoplásicos/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Doxorrubicina/química , Doxorrubicina/farmacocinética , Doxorrubicina/farmacologia , Portadores de Fármacos/química , Portadores de Fármacos/farmacocinética , Células Hep G2 , Humanos , Concentração de Íons de Hidrogênio , Manose/química , Manose/farmacologiaRESUMO
Indomethacin is one of the nonsteroidal anti-inflammatory drugs (NSAIDs) that are widely prescribed drug for pain and inflammation. However, its notoriety of causing gastrointestinal effect, low water solubility, and its short half-life would affect patient compliance and its oral absorption and accordingly justify the need to develop a formula with a controlled and sustained release manner in combination with anti-ulcer drugs. Herein, we synthesized indomethacin-paracetamol co-drug loaded in nanoemulsion and encapsulated in famotiditine loaded polycaprolactone (PCL) nanoparticles. The synthesis of the co-drug was achieved by the formation of a hydrolyzable ester between the indomethacin and paracetamol. The synthesized co-drug was preloading in nanoemulsion (Co-NE), which encapsulated into famotidine PCL nanoparticles utilizing the nanoprecipitation approach. The developed nanosystem showed hydrodynamic size less than 200 nm and the zeta potential value above -30 mV. TEM images confirmed the morphological structure of the formed nanoemulsion and the loaded PCL nanoparticles. Stability studies revealed that the developed nanosystem was stable at different temperatures and pHs over 1 month. Moreover, improvement of the solubilities of these three drugs leading to have a controlled-release multicomponent system of both co-drug and famotidine over 3 days. This multicomponent nanoparticle might be a potential platform to overcome the obstacles of NSAIDs, synergize drugs with different mechanisms of actions by co-encapsulating a small-sized nanoemulsion into PCL nanoparticles for reaching the goal of effective anti-inflammatory therapy.
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Acetaminofen/química , Anti-Inflamatórios não Esteroides/química , Famotidina/química , Antagonistas dos Receptores H2 da Histamina/química , Indometacina/química , Nanopartículas/química , Composição de Medicamentos , Emulsões , Fibroblastos/efeitos dos fármacos , Células HeLa , Humanos , Estrutura MolecularRESUMO
Single walled carbon nanotubes (SWCNT) are currently under intensive investigation by many labs all over the world for being promising candidates for cancer chemotherapy delivery. On the other hand, combretastatin A4 (CA4) is an anticancer drug that induces cell apoptosis by inhibiting tubulin polymerization. However, it has the disadvantage of low water solubility and the non-selective targeting. Therefore, we aim to create nano-drug from the functionalization of SWCNT covalently with CA4 through click reaction in the presence of tetraethylene glycol linker in order to improve its dispersibility. Scanning electron microscopy and transmission electron microscopy showed good dispersibility of the functionalized SWCNT with diameters of 5-15 nm. Moreover, thermogravometric analysis showed that the efficiency of SWCNT functionalization was around 45%. The in vitro release profile of CA4 at physiological conditions showed that approximately 90% of the loaded drug was released over 50 h. After that MTS test was used to determine the suitable concentration range for the in vitro investigation of the SWCNT-CA4. After that the cytotoxic activity of the SWCNT-CA4 was evaluated by flow cytometry using annexin V/propidium iodide (PI) test. In comparison with free CA4, SWCNT-CA4 treatment demonstrated a significant increase in necrotic cells (around 50%) at the expense of the proportion of the apoptotic cells. Moreover, cell cycle PI test demonstrated that free CA4 and SWCNT-CA4 caused G2/M arrest. However with CA4 treatment higher proportion of cells were in the S-phase while with SWCNT-CA4 treatment greater proportion of cells appeared to be in the G1-phase. Taken together, the provided data suggest that the novel SWCNT-CA4 has a significant anticancer activity that might be superior to that of free CA4.
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Nanotubos de Carbono/química , Neoplasias/tratamento farmacológico , Estilbenos/uso terapêutico , Apoptose , Ciclo Celular , Sobrevivência Celular , Química Click , Liberação Controlada de Fármacos , Células HeLa , Humanos , Nanotubos de Carbono/ultraestrutura , Neoplasias/patologia , Estilbenos/síntese química , Estilbenos/química , TermogravimetriaRESUMO
BACKGROUND: Nanomedicine is the medical application of nanomaterials that may have an infinite size with the range less than 100 nm. This science has provided solutions to many of the current limitations in the diagnosis and treatment of diseases. Therefore, the pharmacist's knowledge and awareness of nano-pharmaceutical drugs will increase their availability in the market, and will improve the patient's compliance to their drug therapy. This study aimed to determine the availability of nano-pharmaceutical drugs in Palestinian hospitals and evaluate the extent of pharmacist's knowledge about them. METHODS: A cross-sectional study design questionnaire was used to determine the availability of nano-pharmaceutical drugs based on the database of the ministry of health in the Palestinian hospitals (governmental, private and non- governmental organizations). Moreover, the knowledge of these nano-pharmaceutical drugs among pharmacists working in Palestinian hospitals was assessed based on developed questionnaire from the literature of the pharmaceutical formulations and nano-formulations. The variables were analyzed using Statistical Package for Social Sciences (SPSS 22). RESULT: Fifty six pharmacists from 27 hospitals in the West bank completed the survey. The results regarding the availability of nano-pharmaceutical drugs indicated only eight available in hospitals with a frequency range 0-39.3%. Moreover, pharmacist's knowledge in the pharmaceutical formulations was better than that in nano-formulations. CONCLUSIONS: The availability of nano-pharmaceutical drugs in Palestinian hospitals was not adequate due to the lack of various nano-pharmaceutical drugs. The knowledge among pharmacists regarding nano-pharmaceutical drugs should be improved by providing courses in nanomedicine during the undergraduate pharmacy programs.
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Nanoestruturas , Preparações Farmacêuticas/química , Farmacêuticos/normas , Árabes , Estudos Transversais , Feminino , Conhecimentos, Atitudes e Prática em Saúde , Hospitais/estatística & dados numéricos , Humanos , Masculino , Corpo Clínico Hospitalar/normas , Oriente Médio , Cooperação do Paciente , Preparações Farmacêuticas/provisão & distribuição , Inquéritos e QuestionáriosRESUMO
The development of biobased polymeric materials for wastewater purification has become a demand due to the growing need for water free of hazardous metal ions for safe purposes. The organic components of the OLLW including carbohydrates, phenolics, aromatic acids and others are cost-effective and sustainable choices for this application. This work focuses on a method for turning the organic components of liquid waste from the olive industry (OILW) into a foam-based value-added polymer that has several metal ion binding sites. The process of making the target polymers involved reacting the components of the OILW with hexamethylene diisocyante and 1,4-phnyelene diisocynate to create the polymeric materials LHMIDIC and LPDIC that are in foam forms with urethane linkages, respectively. The adsorption competence of the polymeric foams toward Pb(II) was evaluated as a function of various parameters including adsorbent dose, pH, temperature, initial ion concentration and time. The optimum parameters values that led to a quantitative removal of Pb(II) were identified. The obtained thermodynamic parameters showed that the adsorption by the two foams was spontaneous at room temperature. The isothermal and kinetic values showed that the adsorption by synthesized foams follows a second order kinetic and obeys the Langmuir isothermal model. The foams showed a high tendency for removing multi metal ions present in a real sample of wastewater. The original nature of the starting material used in making the foam, cost and the obtained results showed the potential of using the foam in a large-scale plants of wastewater purification.
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We present a mild and practical carbon nanotubes rings (CNRs) synthesis from non-covalent functionalized and water-soluble linear single-wall carbon nanotubes. The hemi-micellar-supramolecular self-organization of lactose-based glycolipid 1 on the ring surface, followed by photo-polymerization of the diacetylenic function triggered by UV light afforded the first water-soluble and biocompatible CNRs. The obtained donut-like nanoconstructs expose a high density of lactose moieties on their surface, and are able to engage specific interactions with Arachis hypogea lectin similar to glycoconjugates on the cell membrane.
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Lectinas/metabolismo , Nanotubos de Carbono/química , Arachis/metabolismo , Fluorescência , Glicolipídeos/síntese química , Glicolipídeos/química , Lactose , Lectinas/síntese química , Lectinas/química , Nanotubos de Carbono/ultraestrutura , Dodecilsulfato de Sódio/química , Solubilidade , Sonicação , Análise Espectral Raman , Água/químicaRESUMO
Several approaches, including plasmid transfection and viral vectors, were used to deliver genes into cells for therapeutic and experimental purposes. However, due to the limited efficacy and questionable safety issues, researchers are looking for better new approaches. Over the past decade, graphene has attracted tremendous attention in versatile medical applications, including gene delivery, which could be safer than the traditional viral vectors. This work aims to covalently functionalize pristine graphene sheets with a polyamine to allow the loading of plasmid DNA (pDNA) and enhance its delivery into cells. Graphene sheets were successfully covalently functionalized with a derivative of tetraethylene glycol connected to polyamine groups to improve their water dispersibility and capacity to interact with the pDNA. The improved dispersibility of the graphene sheets was demonstrated visually and by transmission electron microscopy. Also, it was shown by thermogravimetric analysis that the degree of functionalization was about 58%. Moreover, the surface charge of the functionalized graphene was +29 mV as confirmed by zeta potential analysis. The complexion of f-graphene with pDNA was achieved at a relatively low mass ratio (10 : 1). The incubation of HeLa cells with f-graphene loaded with pDNA that encodes enhanced green fluorescence protein (eGFP) resulted in the detection of fluorescence signal in the cells within one hour. f-Graphene showed no toxic effect in vitro. Density functional theory (DFT) and quantum theory of atoms in molecules (QTAIM) calculations revealed strong binding with ΔH 298 = 74.9 kJ mol-1. QTAIM between the f-graphene and a simplified model of pDNA. Taken together, the developed functionalized graphene could be used for the development of a new non-viral gene delivery system.
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Carbon nanodots, a family of carbon-based nanomaterials, have been synthesized through different methods from various resources, affecting the properties of the resulting product and their application. Herein, carbon nanodots (CNDs) were synthesized with a green and simple hydrothermal method from sage leaves at 200 °C for 6 hours. The obtained CNDs are well dispersed in water with a negative surface charge (ζ-potential = -11 mV) and an average particle size of 3.6 nm. The synthesized CNDs showed concentration-dependent anticancer activity toward liver cancer (Hep3B) cell lines and decreased the viability of the cancer cells to 23% at the highest used concentration (250 µg ml-1 of CNDs). More interestingly, the cytotoxicity of the CNDs was tested in normal liver cell lines (LX2) revealed that the CNDs at all tested concentrations didn't affect their viability including at the highest concentration showing a viability of 86.7%. The cellular uptake mechanisms of CNDs were investigated and they are thought to be through energy-dependent endocytosis and also through passive diffusion. The main mechanisms of endocytosis were lipid and caveolae-mediated endocytosis. In addition, the CNDs have hindered the formation of 3D spheroids from the Hep3B hepatocellular carcinoma cell line. Hence, it would be concluded that the synthesized CNDs from sage are more highly selective to liver cancer cells than normal ones. The CNDs' cancer-killing ability would be referred to as the production of reactive oxygen species.
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In this work, we present a process for converting olive industry solid waste (OISW) into a value-added material with ionic receptors for use in the removal of toxic metal ions from wastewater. This 3D polymer is a promising adsorbent for large-scale application, since it is a low-cost material made from agricultural waste and showed exceptional performance. The synthesis of the network polymer involved the carboxymethylation of OISW and curing of the carboxymethylated OISW at an elevated temperature to promote the formation of ester linkages between OISW's components. FT-IR, atomic force microscopy, and thermal analysis were performed on the crosslinked product. The adsorption efficiency of the crosslinked carboxymethylated OISW toward Pb(II), Cu(II), and other toxic metal ions present in sewage was evaluated as a function of adsorbent dose, temperature, pH, time, and initial metal ion. The percentage removal of about 20 metal ions present in a sewage sample collected from a sewer plant located in the Palestinian Territories was determined. The adsorption efficiency did not drop even after six cycles of use. The kinetic study showed that the adsorption process follows the Langmuir isotherm model and the second-order adsorption rate. The experimental Qe values of 13.91 and 13.71 mg/g were obtained for Pb(II) and Cu(II) removal, respectively. The thermodynamic results confirm the spontaneous metal bonding to the receptor sites of the crosslinked carboxymethylated OISW.
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Self-assembled nanoparticles present unique properties that have potential applications in the development of a successful drug delivery system. Doxorubicin (DOX) is an important anti-neoplastic anthracycline chemotherapeutic drug widely described. However, it suffers from serious dose-dependent cardiotoxicity. d-Limonene is a major constituent of numerous citrus oils that is considered a specific monoterpene against free radicals producing antioxidant activity. Herein, we aimed to design three types of self-assembled nanodelivery systems (nanoemulsion, niosomes, and polylactide nanoparticles) for loading both DOX and d-limonene to enhance the solubilization of d-limonene and provide antioxidant activity with excellent anticancer activity. As confirmed by dynamic light scattering and transmission electron microscopy, the nanoparticles were prepared successfully with diameter sizes of 52, 180, and 257 nm for the DOX-loaded nanoemulsion, niosomes, and polylactide nanoparticles, respectively. The zeta potential values were above -30 mV in all cases, which confirms the formation of stable nanoparticles. The loading efficiency of DOX was the highest in the case of the DOX-loaded nanoemulsion (75.8%), followed by niosomes (62.8%), and the least was in the case of polylactide nanoparticles with a percentage of 50.2%. The in vitro release study of the DOX-loaded nanoparticles showed a sustained release profile of doxorubicin with the highest release in the case of DOX-loaded PDLLA nanoparticles. The kinetic release model for all developed nanoparticles was the Peppas-Sahlin model, demonstrating DOX release through Fickian diffusion phenomena. Moreover, all developed nanoparticles maintain the antioxidant activity of d-limonene. The cytotoxicity study of the DOX-loaded nanoparticles showed concentration-dependent anticancer activity with excellent anticancer activity in the case of the DOX-loaded nanoemulsion and polylactide nanoparticles. These nanoparticles will be further studied in vivo to prove the cardioprotective effect of d-limonene in combination with DOX.
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BACKGROUND: Rutin is available on the market as a topical formulation for the treatment of several conditions, such as internal bleeding, hemorrhoids, and varicose veins. However, these gels have low solubility and limited bioavailability due to their decreased lipid solubility. OBJECTIVE: In this study, we aimed to synthesize potentially novel lipophilic rutin prodrugs. The suggested library of these rutin prodrugs includes changing the solubility profile to facilitate rutin transport across biological barriers, thereby improving drug delivery through topical application. METHODS: Six rutin derivatives were synthesized based on the ester prodrug strategy. The synthesized compounds were formulated as topical ointments, and their permeability via Franz diffusion was measured. An ultraviolet (UV) analytical method was developed in our laboratories to quantify rutin derivatives both as raw materials and in final dosage forms. The analytical method was then validated. RESULTS: The results of Franz diffusion analyses showed that transdermal permeability increased by 10-fold for decaacetylated rutin compared to the other esterified rutins. A simple analytical method for the analysis of the formulated rutin ester was developed and validated. Moreover, the formulated ointment of decaacetylated rutin in our research laboratory was found to be stable under stability accelerated conditions. Synthesis of potentially more lipophilic compounds would yield novel rutin prodrugs suitable for topical formulation. CONCLUSION: This project provides a synthetic approach for many similar natural products. The research idea and strategy followed in this research project could be adapted by pharmaceutical and herbal establishments.
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Pró-Fármacos , Rutina , Administração Cutânea , Disponibilidade Biológica , Lipídeos , SolubilidadeRESUMO
Tissue engineering is one of the hot topics in recent research that needs special requirements. It depends on the development of scaffolds that allow tissue formation with certain characteristics, carbon nanotubes (CNTs)-collagen composite attracted the attention of the researchers with this respect. However, CNTs suffer from low water dispersibility, which hampered their utilization. Therefore, we aim to functionalize CNTs non-covalently with pyrene moiety using an appropriate hydrophilic linker derivatized from polyethylene glycol (PEG) terminated with hydroxyl or carboxyl group to disperse them in water. The functionalization of the CNTs is successfully confirmed by TEM, absorption spectroscopy, TGA, and zeta potential analysis. 3T3 cells-based engineered connective tissues (ECTs) are generated with different concentrations of the functionalized CNTs (f-CNTs). These tissues show a significant enhancement in electrical conductivity at a concentration of 0.025%, however, the cell viability is reduced by about 10 to 20%. All ECTs containing f-CNTs show a significant reduction in tissue fibrosis and matrix porosity relative to the control tissues. Taken together, the developed constructs show great potential for further in vivo studies as engineered tissue.
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Nanotubos de Carbono , Animais , Camundongos , Nanotubos de Carbono/química , Polietilenoglicóis/química , Porosidade , Engenharia Tecidual/métodos , ÁguaRESUMO
[This corrects the article DOI: 10.1039/D1RA09273A.].
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Carbon nanodots (CNDs) have many fascinating properties, such as optical properties (UV-Visible absorption and fluorescence emission), which make them good candidates in many applications, such as photocatalysts for the degradation of several organic pollutants. This study aims to synthesize CNDs from olive solid wastes at different carbonization temperatures from 300 to 900 °C and study the effect on the optical properties of the CNDs, such UV-Vis, fluorescence, quantum yield, and energy bandgap, in addition to the influence on the photoactivity of the CNDs as photocatalysts for the degradation of methylene blue (MB). CNDs were prepared from olive solid wastes (OSWs) by pyrolysis at different temperatures (300-900 °C) for conversion to carbonized material, and then oxidized chemically in the presence of hydrogen peroxide (H2O2). It was found that an increase in the carbonization temperature of the OSWs leads to an increase in the product yield with a maximum value at 500 °C, and it then decreased dramatically. On the other hand, a decrease in fluorescence due to the diminishment of oxygen groups and the destruction of the surface of the CNDs was observed. The higher quantum yield (5.17%) and bandgap (2.77 eV) were achieved for CNDs prepared from OSWs that carbonized at 300 °C. The rate and degradation efficiency of MB were studied with the different synthesized CNDs, and it was found that an increase in the carbonization temperature leads to a decrease in the rate and degradation efficiency of MB, with the highest degradation rate of 0.0575 min-1 and degradation efficiency of 100% after 120 minutes of light irradiation being realized for the sample carbonized at 300 °C.
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Carbon nanodots, a class of carbon nano-allotropes, have been synthesized through different routes and methods from a wide range of precursors. The selected precursor, synthetic method, and conditions can strongly alter the physicochemical properties of the resulting material and their intended applications. Herein, carbon nanodots (CNDs) have been synthesized from d-glucose by combining pyrolysis and chemical oxidation methods. The effect of the pyrolysis temperature, equivalents of oxidizing agent, and refluxing time were studied on the product and quantum yield. In the optimum conditions (pyrolysis temperature of 300 °C, 4.41 equiv of H2O2, 90 min of reflux) CNDs were obtained with 40% and 3.6% of product and quantum yields, respectively. The obtained CNDs are negatively charged (ζ-potential = -32 mV), excellently dispersed in water, with average diameter of 2.2 nm. Furthermore, ammonium hydroxide (NH4OH) was introduced as dehydrating and/or passivation agent during CNDs synthesis resulting in significant improvement of both product and quantum yields of about 1.5 and 3.76-fold, respectively. The synthesized CNDs showed a broad spectrum of antibacterial activities toward different Gram-positive and Gram-negative bacteria strains. Both synthesized CNDs caused highly colony forming unit reduction (CFU), ranging from 98% to 99.99% for most of the tested bacterial strains. However, CNDs synthesized in the absence of NH4OH, due to a negatively charged surface enriched in oxygenated groups, performed better in zone inhibition and minimum inhibitory concentration. The elevated antibacterial activity of high-oxygen-containing carbon nanodots is directly correlated to their ROS formation ability.
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Supramolecular self-assembly of conjugated diacetylenic amphiphile-tethered ligands photopolymerize to afford polydiacetylene (PDA) functional liposomes. Upon specific interaction with a variety of biological analytes in aqueous solution, PDA exhibits rapid colorimetric transitions. The PDA nanoassemblies, which are excellent membrane mimics, include an ene-yne polymeric reporter responsible for the chromatic transitions and the molecular recognition elements that are responsible for selective and specific binding to the biological target. A bottleneck in the fabrication of these colorimetric biosensors is the preparation of the diacetylenic monomer embedded with the recognition element of choice. In the present work, we make use of copper-catalyzed azide-alkyne cycloaddition (CuAAC) as key step in the preparation of sugar-coated liposome biosensors. The regioselective click ligation of the triacetylenic N-(2-propynyl)pentacosa-10,12-diynamide (NPPCDAM) with a variety of mannose- and lactose-tethered azides afforded chemo- and regioselectively the corresponding 1,2,3-triazole. The obtained diacetylenic monomers were incorporated efficiently into vesicles to afford functional mannose- and lactose-coated glycoliposomes. The obtained PDA-based click glycoliposomes have been characterized by using transmission electronic microscopy (TEM), dynamic light scattering (DLS), and UV/Vis spectroscopy. The efficiency of the reported approach was demonstrated by the rapid optimization of the hydrophilic spacer between the lipidic matrix and the mannose head group for the colorimetric detection of Concavalin A.
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Alcinos/química , Azidas/química , Concanavalina A/análise , Cobre/química , Glicolipídeos/química , Lipossomos/síntese química , Polímeros/síntese química , Poli-Inos/síntese química , Triazóis/síntese química , Técnicas Biossensoriais , Catálise , Química Click , Colorimetria , Lipossomos/química , Lipossomos/ultraestrutura , Estrutura Molecular , Polímero Poliacetilênico , Polímeros/química , Poli-Inos/química , Triazóis/químicaRESUMO
Non-steroidal anti-inflammatory drugs (NSAIDs) are widely prescribed for the treatment of various types of inflammatory conditions. Diclofenac is a very common NSAID that is utilized to relieve pain and reduce fever and, most importantly, inflammation. However, it suffers from low water solubility and a low dissolution profile. Therefore, we aim to develop a new drug delivery system based on the synthesis of amphiphilic structures that are capable of self assembling into nano-micelles which will be a water-soluble delivery system for the diclofenac. The amphiphilic structure consists of a hydrophilic moiety of triethylene glycol (TEG), polyethylene glycol PEG 400, or PEG 600 linked with the hydrophobic drug diclofenac through an ester linkage. The diclofenac derivatives were successfully synthesized as confirmed by nuclear magnetic resonance. Moreover, the formation of the micellar structure of the synthesized amphiphilic derivatives was confirmed by atomic force microscopy obtaining a spherical shape of the micelles with average diameters of 200 nm for Dic-PEG400-Dic, and 110 nm for Dic-PEG600-Dic. The critical micelle concentration has been determined as 2.7 × 10-3 mg mL-1 for Dic-PEG400-Dic, and 1 × 10-4 mg mL-1 for Dic-PEG600-Dic. The in vitro diclofenac release profile by esterase enzyme was conducted and showed almost complete conversion to free diclofenac within 35 h in the case of Dic-PEG400-Dic micelles and more than 85% of Dic-PEG600-Dic micelles. Then the anti-inflammatory activity was determined by testing the TNF-α production in LPS-stimulated Balb/c mice. Diclofenac micelles significantly suppressed TNF-α production after a 5 mg kg-1 dose was given. The developed micelles showed TNF-α inhibition up to 87.4% and 84% after 48 hours of treatment in the case of Dic-PEG400-Dic and Dic-PEG600-Dic micelles respectively in comparison to 42.3% in the case of diclofenac alone. Dic-PEG400-Dic micelles showed the most potent anti-inflammatory activity with improved TNF-α suppression through time progress. Therefore, the developed nano-micelles provide a facile synthetic approach to enhance diclofenac water solubility, improve the anti-inflammatory effect and achieve a sustained release profile to get better patient compliance.
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BACKGROUND: Under certain conditions, the physiological repair of connective tissues might fail to restore the original structure and function. Optimized engineered connective tissues (ECTs) with biophysical properties adapted to the target tissue could be used as a substitution therapy. This study aimed to investigate the effect of ECT enforcement by a complex of multiwall carbon nanotubes with chitosan (C-MWCNT) to meet in vivo demands. MATERIALS AND METHODS: ECTs were constructed from human foreskin fibroblasts (HFF-1) in collagen type I and enriched with the three different percentages 0.025, 0.05 and 0.1% of C-MWCNT. Characterization of the physical properties was performed by biomechanical studies using unidirectional strain. RESULTS: Supplementation with 0.025% C-MWCNT moderately increased the tissue stiffness, reflected by Young's modulus, compared to tissues without C-MWCNT. Supplementation of ECTs with 0.1% C-MWCNT reduced tissue contraction and increased the elasticity and the extensibility, reflected by the yield point and ultimate strain, respectively. Consequently, the ECTs with 0.1% C-MWCNT showed a higher resilience and toughness as control tissues. Fluorescence tissue imaging demonstrated the longitudinal alignment of all cells independent of the condition. CONCLUSION: Supplementation with C-MWCNT can enhance the biophysical properties of ECTs, which could be advantageous for applications in connective tissue repair.