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1.
Bioimpacts ; 13(3): 241-253, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37431480

RESUMO

Introduction: Drug repurposing is an effective strategy for identifying the use of approved drugs for new therapeutic purposes. This strategy has received particular attention in the development of cancer chemotherapy. Considering that a growing body of evidence suggesting the cholesterol-lowering drug ezetimibe (EZ) may prevent the progression of prostate cancer, we investigated the effect of EZ alone and in combination with doxorubicin (DOX) on prostate cancer treatment. Methods: In this study, DOX and EZ were encapsulated within a PCL-based biodegradable nanoparticle. The physicochemical properties of drug containing nanoparticle based on PCL-PEG-PCL triblock copolymer (PCEC) have been exactly determined. The encapsulation efficiency and release behavior of DOX and EZ were also studied at two different pHs and temperatures. Results: The average size of nanoparticles (NPs) observed by field emission scanning electron microscopy (FE-SEM) was around 82±23.80 nm, 59.7±18.7 nm, and 67.6±23.8 nm for EZ@PCEC, DOX@PCEC, and DOX+EZ@PCEC NPs, respectively, which had a spherical morphology. In addition, DLS measurement showed a monomodal size distribution of around 319.9, 166.8, and 203 nm hydrodynamic diameters and negative zeta potential (-30.3, -6.14, and -43.8) mV for EZ@PCEC, DOX@PCEC, and DOX+EZ@PCEC NPs, respectively. The drugs were released from the NPs sustainably in a pH and temperature-dependent manner. Based on the MTT assay results, PCEC copolymer exhibited negligible cytotoxicity on the PC3 cell line. Therefore, PCEC was a biocompatible and suitable nano-vehicle for this study. The cytotoxicity of the DOX-EZ-loaded NPs on the PC3 cell line was higher than that of NPs loaded with single drugs. All the data confirmed the synergistic effect of EZ in combination with DOX as an anticancer drug. Furthermore, fluorescent microscopy and DAPI staining were performed to show the cellular uptake, and morphological changes-induced apoptosis of treated cells. Conclusion: Overall, the data from the experiments represented the successful preparation of the nanocarriers with high encapsulation efficacy. The designed nanocarriers could serve as an ideal candidate for combination therapy of cancer. The results corroborated each other and presented successful EZ and DOX formulations containing PCEC NPs and their efficiency in treating prostate cancer.

2.
Adv Pharm Bull ; 13(2): 317-327, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37342377

RESUMO

Purpose: Mesoporous silica nanoparticles (MSNs) have drawn substantial interest as drug nanocarriers for breast cancer therapy. Nevertheless, because of the hydrophilic surfaces, the loading of well-known hydrophobic polyphenol anticancer agent curcumin (Curc) into MSNs is usually very low. Methods: For this purpose, Curc molecules were loaded into amine-functionalized MSNs (MSNs-NH2 -Curc) and characterized using thermal gravimetric analysis (TGA), Fourier-transform infrared (FTIR), field emission scanning electron microscope (FE-SEM), transmission electron microscope (TEM), Brunauer-Emmett-Teller (BET). MTT assay and confocal microscopy, respectively, were used to determine the cytotoxicity and cellular uptake of the MSNs-NH2 - Curc in the MCF-7 breast cancer cells. Besides, the expression levels of apoptotic genes were evaluated via quantitative polymerase chain reaction (qPCR) and western blot. Results: It was revealed that MSNs-NH2 possessed high values of drug loading efficiency and exhibited slow and sustained drug release compared to bare MSNs. According to the MTT findings, while the MSNs-NH2 -Curc were nontoxic to the human non-tumorigenic MCF-10A cells at low concentrations, it could considerably decrease the viability of MCF-7 breast cancer cells compared to the free Curc in all concentrations after 24, 48 and 72 hours exposure times. A cellular uptake study using confocal fluorescence microscopy confirmed the higher cytotoxicity of MSNs-NH2 -Curc in MCF-7 cells. Further, it was found that the MSNs-NH2 -Curc could drastically affect the mRNA and protein levels of Bax, Bcl-2, caspase 3, caspase 9, and hTERT relative to the free Curc treatment. Conclusion: Taken together, these preliminary results suggest the amine-functionalized MSNs-based drug delivery platform as a promising alternative approach for Curc loading and safe breast cancer treatment.

3.
J Nanobiotechnology ; 20(1): 91, 2022 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-35193612

RESUMO

Novel temperature and pH dual-sensitive amphiphilic micelles were fabricated exploiting the host-guest interaction between benzimidazole-terminated PHEMA-g-(PCL-BM) and ß-CD-star-PMAA-b-PNIPAM. The fabricated graft copolymer had a brush-like structure with star side chains. The micelles were utilized as dual-responsive nanocarriers and showed the LCST between 40 and 41 °C. The acidic pH promoted the dissociation of the PHEMA-g-(PCL-BM: ß-CD-star-PMAA-b-PNIPAM) micelles. DOX.HCl was loaded into the core of the micelles during self-assembly in an aqueous solution with a high encapsulation efficacy (97.3%). The average size of the amphiphilic micelles was about 80 nm, suitable size for the enhanced permeability and retention effect in tumor vasculature. In an aqueous environment, these micelles exhibited very good self-assembly ability, low CMC value, rapid pH- and thermo-responsiveness, optimal drug loading capacity, and effective release of the drug. The biocompatibility was confirmed by the viability assessment of human breast cancer cell line (MCF-7) through methyl tetrazolium assay. DOX-loaded micelles displayed excellent anti-cancer activity performance in comparison with free DOX.


Assuntos
Micelas , beta-Ciclodextrinas , Benzimidazóis/química , Doxorrubicina/química , Doxorrubicina/farmacologia , Portadores de Fármacos/química , Humanos , Concentração de Íons de Hidrogênio , beta-Ciclodextrinas/química
4.
Mol Divers ; 25(2): 889-897, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-32078143

RESUMO

In this research, the synthesis of the quinazolinone derivatives by the reaction of diaminoglyoxime with anthranilic acid or methyl 2-amino benzoate over an acetic acid-functionalized magnetic silica-based catalyst in water was described. The acetic acid-functionalized catalyst was prepared using a three-step procedure from magnetite NPs that initially coated with a layer of silica through the sol-gel process, modified with an aminosilane layer and functionalized with bromoacetic acid. The catalyst was characterized by means of spectroscopic and microscopic techniques, and its activity was investigated for the synthesis of the quinazolinones, bisquinazolinone and oxadiazole quinazolinones obtained from diaminoglyoxime in water at room temperature.


Assuntos
Ácido Acético/química , Nanopartículas de Magnetita/química , Quinazolinonas/síntese química , Dióxido de Silício/química , Catálise , Química Verde , Oximas/química , Quinazolinonas/química , ortoaminobenzoatos/química
5.
Tanaffos ; 20(4): 353-362, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36267933

RESUMO

Background: Today, increasing attention is being paid to the application of biocompatible polymers as drug carriers with low cytotoxicity in drug delivery systems to enhance the therapeutic effects of anticancer agents. Materials and Methods: In this study, a biocompatible synthetic polymer (grafted on graphene oxide), composed of N-isopropylacrylamide and 1-vinyl-2-pyrrolidone with L-lysine segments (Lys/PNIPAM-PVP/GO), was developed as a nano-vehicle for the drug. This platform was used for the delivery of fluorouracil (FU) to A549 human lung cancer cells. The superior characteristics of the platform included low-cost precursors, easy synthesis, and the presence of many functional groups for loading drugs. To determine and compare the cytotoxic effects of free FU and its formulated form on the A549 cells, MTT assay was performed; the results showed no significant toxicity difference between the two treated groups (free and formulated FU). For further evaluations, cellular uptake assays were performed via fluorescence microscopy and flow cytometry. Results: Both analyses revealed the low internalization of nano-vehicle into the A549 cells, with 4.31% and 8.75% cellular uptakes in the first two and four hours of treatment. Therefore, the low penetration rate reduced the toxicity of drug-loaded nano-vehicle. Conclusion: Finally, DAPI staining and Annexin V-FITC staining were performed as complementary techniques to determine cell apoptosis.

6.
Mater Sci Eng C Mater Biol Appl ; 118: 111384, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33254991

RESUMO

Temperature-responsive drug-loaded electrospun nanofibers have gained huge critical attention as efficient localized implantable devices in preventing cancer local recurrence. In this regard, a smart hyperthermia nanofiber with the simultaneous heat-generation and dual-stage drug release ability in response to 'ON-OFF' switching of an alternating magnetic field (AMF) for improved hyperthermic chemotherapy has been developed. The smart hyperthermia nanofibrous scaffolds are fabricated via electrospinning a temperature-responsive copolymer blended with iron oxide (II, III) magnetic nanoparticles (MNPs, 10 nm), metformin (MET), and mesoporous silica nanoparticles (MSNs) loaded with MET (MSNs@MET). It was found that all the magnetic nanofibers (MNFs) possess heat generation property and 'ON-OFF' switchable heating ability. The swelling ratio with reversible alterations and the corresponding drug discharge in response to AMF application with 'ON-OFF' switching was also demonstrated. MET-MNFs showed an initial rapid discharge in the 1st cycle of AMF application while MET released from MET@MSNs-MNFs exhibited a sustained release without the initial rapid discharge. It was found that MET-MET@MSNs-MNFs displayed a blend of initial rapid discharge and late prolonged drug discharge. In a magnetic field for 300 s during the second and third days, the metabolic activity of B16F10 skin melanoma cells incubated with all types of MNFs was decreased. Importantly, MET-MET@MSNs-MNFs had enhanced cytotoxicity than the MET-MNFs and MET@MSNs-MNFs (P < .05), due to the double effects of heat and dual-stage drug release. These results demonstrated that the proposed two-stage drug discharge approach plus hyperthermia is more desirable to standard chemotherapy regimens and might effectively induce cytotoxicity via a synergistic effect over a relatively long time.


Assuntos
Hipertermia Induzida , Nanofibras , Nanopartículas , Neoplasias , Liberação Controlada de Fármacos , Humanos , Hipertermia , Dióxido de Silício
7.
Artif Cells Nanomed Biotechnol ; 47(1): 443-454, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30688104

RESUMO

Despite the advances in the development of chemotherapeutic agents, resistance to chemotherapy and adverse side effects are still big challenges against successful cancer treatment. To overcome these problems, one strategy is the application of nanomaterials and drug delivery systems to efficiently deliver the anticancer agents to tumour tissues with minimum toxic effects on healthy organs. In this study a graphene oxide nanohybrid (GO/NHs) was designed and fabricated for the delivery of chemotherapeutic agent fluorouracil (FU) to the breast cancer MCF7 cells. After preparation and characterization of GO/NHs, several biological analysis including haemolysis assay, cytotoxicity assay, cellular uptake, apoptosis assay, and protein expression were performed. The cytotoxic effects of FU, FU loaded GO/NHs (FU-GO/NHs), and blank GO/NHs was determined by MTT assay. The results of MTT assay showed no significant cytotoxicity for blank nano-hybrid on MCF7 cells. Furthermore, FU-GO/NHs were more cytotoxic than free FU. The uptake analysis results showed that developed nanocarrier could completely be internalized into the cells in the first hour. Besides, apoptotic effects and nuclear morphology changes of cells was evaluated by DAPI staining under fluorescent microscopy. Protein expression levels of p53, PARP, cleaved PARP, Bcl-2, and Bax were determined by western blot analysis. Western blot results showed higher levels of p53 and cleaved PARP after treatment with FU-GO/NHs, however, no substantial effect was observed for Bax and Bcl-2 protein concentrations.


Assuntos
Acrilamidas/química , Fluoruracila/química , Grafite/química , Lisina/química , Nanoestruturas/química , Óxidos/química , Povidona/química , Portadores de Fármacos/química , Portadores de Fármacos/toxicidade , Liberação Controlada de Fármacos , Fluoruracila/farmacologia , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Hemólise/efeitos dos fármacos , Humanos , Células MCF-7 , Modelos Moleculares , Conformação Molecular , Poli(ADP-Ribose) Polimerases/metabolismo , Proteólise/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Proteína X Associada a bcl-2/metabolismo
8.
Environ Monit Assess ; 187(9): 554, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26245852

RESUMO

This work describes a novel Fe3O4@SiO2@polythiophene magnetic nanocomposite and its application in the preconcentration of Hg(II) ions. The parameters affecting the preconcentration procedure were opted by a Box-Behnken design through response surface methodology. Three factors (uptake time, magnetic nanosorbent amount, and pH of sample) were selected as the main factors affecting the sorption step, while four variables (type, volume and concentration of the eluent as well as the elution time) were selected as main factors in the optimization study of the elution step. Following the sorption and elution of Hg(II), it was quantified by cold vapor atomic absorption spectrometry. Under the optimum condition, the limit of detection was 0.02 ng mL(-1) and all the relative standard deviations were less than 9.2 %. The obtained sorption capacity of this new sorbent was 59 mg g(-1). Finally, this nanocomposite was successfully applied to the rapid extraction of trace quantities of Hg(II) ions in sea food samples and satisfactory results were obtained.


Assuntos
Mercúrio/análise , Nanocompostos/química , Polímeros/química , Dióxido de Silício/análise , Tiofenos/química , Monitoramento Ambiental , Compostos Férricos/química , Análise de Alimentos , Contaminação de Alimentos , Íons/análise , Magnetismo , Microscopia Eletrônica de Transmissão , Nanotecnologia/métodos , Alimentos Marinhos/análise , Espectrofotometria Atômica/métodos , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios X
9.
Artigo em Inglês | MEDLINE | ID: mdl-25621454

RESUMO

This paper describes the synthesis and application of a novel magnetic metal-organic framework (MOF) [(Fe3O4-benzoyl isothiocyanate)/Cu3(benzene-1,3,5-tricarboxylate)2] to pre-concentrate trace amounts of Cd(II), Pb(II), Zn(II) and Cr(III) ions and their determination by flame atomic absorption spectrometry. A Box-Behnken design was used to find the parameters affecting the pre-concentration procedure through response surface methodology. Three factors including uptake time, amount of the magnetic sorbent and pH of the sample were selected as affecting factors in the sorption step, and four factors including type, volume and concentration of the eluent as well as the elution time were selected in the elution step for the optimisation study. The opted values were 30 mg, 10.1 min, 5.9, EDTA, 4.0 ml, 0.57 mol l(-1) EDTA solution and 13.0 min for the amount of the magnetic sorbent, uptake time, pH of the sample, type, volume, concentration of the eluent, and elution time, respectively. The limits of detection (LODs) were 0.12, 0.7, 0.16, and 0.4 ng ml(-1) for Cd(II), Pb(II), Zn(II) and Cr(III) ions, respectively. The relative standard deviations (RSDs) of the method were less than 7.2% for five separate batch experiments for the determination of 30 µg l(-1) of Cd(II), Pb(II), Zn(II) and Cr(III) ions. The sorption capacity of the [(Fe3O4-benzoyl isothiocyanate)/MOF] was 175 mg g(-1) for Cd(II), 168 mg g(-1) for Pb(II), 210 mg g(-1) for Zn(II) and 196 mg g(-1) for Cr(III). It was found that the magnetic MOF nanocomposite demonstrated a higher capacity compared with Fe3O4-benzoyl isothiocyanate. Finally, the magnetic MOF nanocomposite was successfully applied to the rapid extraction of trace amounts of the heavy metal ions from vegetable samples.


Assuntos
Metais Pesados/análise , Nanocompostos/química , Verduras/química , Cádmio/análise , Cromo/análise , Análise de Alimentos , Contaminação de Alimentos/análise , Íons/análise , Chumbo/análise , Limite de Detecção , Reprodutibilidade dos Testes , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios X , Zinco/análise
10.
J Sep Sci ; 38(7): 1179-86, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25631191

RESUMO

This work describes a novel functionalized magnetic metal-organic framework nanocomposite [(Fe3O4-2,5-dimercapto-1,3,4-thiadiazole)/metal-organic framework] and its application in the preconcentration of Hg(II) ions. The parameters affecting the preconcentration procedure were optimized by a Box-Behnken design through response surface methodology. Three variables (uptake time, magnetic nanosorbent amount, and pH value) were selected as the main factors affecting the sorption step, while four variables (type, volume, and concentration of the eluent; and elution time) were selected as main factors in the optimization study of the elution step. Following the sorption and elution of analytes, the ions were quantified by cold vapor atomic absorption spectrometry. Under the optimum conditions, the limit of detection was 0.01 ng/mL and all the relative standard deviations were less than 10%. The obtained sorption capacity (in mg/g) of this new sorbent was 124. Ultimately, this nanocomposite was successfully applied to the rapid extraction of trace quantities of Hg(II) ions in seafood samples and satisfactory results were obtained.


Assuntos
Magnetismo , Mercúrio/análise , Nanocompostos , Compostos Orgânicos/química , Alimentos Marinhos/análise , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios X
11.
Sci Pharm ; 81(1): 281-96, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23641345

RESUMO

The present research work describes the synthesis and evaluation of new acrylic-type polymeric systems having degradable ester bonds linked to ibuprofen as materials for drug delivery. Ibuprofen was linked to 2-hydroxy-propyl methacrylate by an activated ester methodology in a one-pot procedure with a high yield. The resulting material was copolymerized with either 2-hydroxyethyl methacrylate or methyl methacrylate (in 1:3 mole ratios) by the free radical polymerization method, utilizing azoisobutyronitrile at 65-70 °C. The characterization of the resulting products by FTIR, (1)H NMR, (13)C NMR, DSC, and elemental analysis confirmed their synthesis successfully. Ibuprofen release from the obtained polymers was preliminarily evaluated at different buffered solutions (pH 1, 7.4, and 10) into dialysis bags to show the capacity of prodrugs to release the drug under hydrolytic conditions. Detection of hydrolysis by UV spectroscopy at selected intervals showed that the drug can be released by selective hydrolysis of the ester bond at the side of the drug moiety. The release profiles indicated that the hydrolytic behavior of polymers is strongly based on the polymer hydrophilicity and the pH value of the hydrolysis solution. The results suggest that these polymers could be useful in controlled release systems.

12.
Int J Pharm ; 356(1-2): 167-73, 2008 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-18289807

RESUMO

2-(1-Propene)oxyethyl phthalimide (3) was synthesized from reaction of 1-(2-chloroethoxy)propene (2) with potassium-t-butoxide and polymerized by cationic polymerization method using BF(3).OEt(2) as an initiator at -78 degrees C to obtain polymer 4. Then, polymer 4 was hydrazinolized by hydrazine and gave polymer 5 containing pendent amine groups. Three non-steroidal anti-inflammatory drugs (NSAIDs), ibuprofen, ketoprofen and naproxen were covalently linked to polymer 5 through amide groups by reacting chloroacylated drugs 6a-6c with amine groups of polymer 5 to obtain three polymeric prodrugs 7a-7c. All the synthesized compounds were characterized by FT-IR, (1)H and (13)C NMR spectroscopy techniques. The polymer-drug conjugates were hydrolyzed in cellophane member dialysis bags containing aqueous buffered solutions (pH 1, 7.4 and 10) at 37 degrees C and the hydrolysis solutions were detected by UV spectrophotometer at selected intervals. The results showed that the drugs could be released by hydrolysis of the amide bonds. The release profiles indicated that the hydrolytic behavior of polymeric prodrugs strongly depends on the pH of the hydrolysis solution. The results suggested that the vinyl ether type polymers could be the useful carriers for release of profens in controlled release systems.


Assuntos
Anti-Inflamatórios não Esteroides/síntese química , Pró-Fármacos/síntese química , Compostos de Vinila/química , Anti-Inflamatórios não Esteroides/administração & dosagem , Anti-Inflamatórios não Esteroides/química , Preparações de Ação Retardada , Concentração de Íons de Hidrogênio , Hidrólise , Ibuprofeno/administração & dosagem , Ibuprofeno/química , Cetoprofeno/administração & dosagem , Cetoprofeno/química , Espectroscopia de Ressonância Magnética , Naproxeno/administração & dosagem , Naproxeno/química , Polímeros/química , Espectrofotometria Ultravioleta , Espectroscopia de Infravermelho com Transformada de Fourier
13.
Int J Pharm ; 316(1-2): 68-73, 2006 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-16567069

RESUMO

New acrylic type polymeric systems having degradable ester bonds linked to ibuprofen were synthesized and evaluated as materials for drug delivery. Methacryloyloxy(2-hydroxy)propyl-4-isobutyl-alpha-methylphenyl acetate (MOPE), a new methacrylic derivative of ibuprofen in which the drug is separated from the methacrylic backbone by an oxy(2-hydroxy)propylene spacer arm and hydrolytically labile ester bond, was synthesized from reaction of glycidyl methacrylate with ibuprofen. The resulting drug containing monomer was copolymerized with methacrylamide, 2-hydroxyethyl methacrylate, N-vinyl-2-pyrrolidone or n-butyl methacrylate by free radical polymerization method in N,N-di-methylformamide (DMF) solution, utilizing azobisisobutyronitrile as initiator at the temperature range 65-70 degrees C. The obtained polymers were characterized by FT-IR, 1H NMR and 13C NMR spectroscopy. Gel permeation chromatography (GPC) was used for determination of average molecular weights of drug-polymer conjugates and showed that the polydispersity indices of the polymers are in the range of 1.9-2.3. Drug release studies were performed by hydrolysis in buffered solutions (pH 1 and 8) at 37 degrees C. Detection of hydrolysis by UV spectroscopy at selected interval showed that the drug can be released by selective hydrolysis of the ester bond at the side of drug moiety. The release profiles indicated that the hydrolytic behavior of polymeric prodrugs is strongly based on the hydrophilicity of polymer and the pH of the hydrolysis solution. The hydrophilic polymers containing ibuprofen were hydrolyzed in buffer solutions rather than the hydrophobic polymers.


Assuntos
Acrilatos/síntese química , Ibuprofeno/síntese química , Polímeros/síntese química , Pró-Fármacos/síntese química , Acrilatos/química , Hidrólise , Ibuprofeno/química , Estrutura Molecular , Polímeros/química , Pró-Fármacos/química , Solubilidade , Comprimidos com Revestimento Entérico
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