Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 12 de 12
Filtrar
Mais filtros











Base de dados
Intervalo de ano de publicação
1.
Int J Biol Macromol ; 164: 2813-2817, 2020 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-32853612

RESUMO

This work proposes the development of a starch-based drug carrier for fluoxetine (FLX) delivery and evaluate the improvement of the drug antibacterial activity. The starch nanocapsules were prepared via interfacial polyaddition reaction presenting a core-shell morphology, based on polyurethane linkage, with a particle size in the range 250-300 nm. Furthermore, FLX-loaded nanocapsules were evaluated regarding antibacterial potential against Staphylococcus aureus (ATCC® 6538P ™) and its clinical strains of methicillin-resistant. As expected, the FLX-loaded presented lower minimum inhibitory concentration (MIC) values, in the range of 190-95 µg mL-1, against all isolated microorganisms in comparison to FLX, 255 µg mL-1. According to results, the FLX-loaded starch nanocapsules have successfully improved drug antibacterial activity, generating promising perspectives on the field of the hydrophilic drug delivery systems.


Assuntos
Antibacterianos/farmacologia , Fluoxetina/farmacologia , Amido/química , Antibacterianos/química , Portadores de Fármacos , Fluoxetina/química , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Nanocápsulas , Tamanho da Partícula , Staphylococcus aureus/efeitos dos fármacos
2.
Environ Sci Pollut Res Int ; 24(7): 6233-6240, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27525739

RESUMO

This work evaluated the photo-Fenton degradation of two pharmaceuticals extensively used in human medicine, ciprofloxacin (CIP), and fluoxetine (FLU) when present in an anaerobic pre-treated hospital effluent (HE) at low concentration (100 µg L-1). Operational parameters such as concentration of hydrogen peroxide, iron, and initial pH as well as the effect of iron citrate complex were evaluated considering the degradation of the pharmaceuticals. Iron citrate complex (Fecit) influenced significantly FLU degradation at pH 4.5 achieving 80 % after 20 min, while with iron nitrate only 36 % degradation was obtained after the same time. However, only a slight effect was observed on CIP degradation, achieving 86 % with Fecit and 75 % with Fe(NO3)3, after 20 min. Samples of HE used in this work were previously treated in an anaerobic reactor followed by sand filtration; however, the presence of pharmaceuticals was detected. Degradation of both FLU and CIP was significantly hindered when present in HE, due to the relatively high content of organic (39.6 mg L-1) and inorganic (12.5 mg L-1) carbon, which may have consumed ·OH in side reactions. However, the iron cycle reduction was not affected by the matrix in the presence of citrate. Despite the recalcitrance of the matrix (no total organic carbon removal), it was possible to achieve over 50 % degradation of both pharmaceuticals after 90 min.


Assuntos
Ciprofloxacina/química , Fluoxetina/química , Hospitais , Peróxido de Hidrogênio/química , Ferro/química , Fotólise , Poluentes Químicos da Água/química , Filtração , Concentração de Íons de Hidrogênio , Oxigênio/química
3.
J Environ Manage ; 182: 486-495, 2016 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-27526086

RESUMO

Pharmaceutical persistent pollutants pose a serious threat to the environment. The aim of this study was to use, for the first time, hydroxyapatite-based biomaterials as photocatalysts to degrade micropollutants. Diclofenac and fluoxetine were selected for these initial tests. Hydroxyapatite (Ca10(PO4)(OH)2, HAp) is one of the most commonly used biomaterials/bioceramics, being a major constituent of bone. In this work sustainable HAp-based materials of marine origin, obtained from cod fish bones, were used; these photocatalysts were previously fully studied and characterised. Both single-phase HAp and HAp-titania multicomponent materials (1 wt% TiO2) were employed as UV light photocatalysts, the latter showing better performance, indicated by higher degradation rates of both compounds. The HAp-titania photocatalyst showed excellent degradation of both persistent pollutants, the maximum degradation performance being 100% for fluoxetine and 92% for diclofenac, with pollutant and photocatalyst concentrations of 2 ppm and 4 g/L, respectively. Variations in features such as pollutant and photocatalyst concentrations were investigated, and results showed that generally fluoxetine was degraded more easily than diclofenac. The photocatalyst's crystallinity was not affected by the photodegradation reaction; indeed the material exhibited good photostability, as the degradation rate did not decrease when the material was reused. Tests were also performed using actual treated wastewater; the photocatalyst was still effective, even if with lower efficiency (-20% and -4% for diclofenac and fluoxetine, respectively). TOC analysis showed high but incomplete mineralisation of the pollutants (maximum 60% and 80% for DCF and FXT, respectively).


Assuntos
Materiais Biocompatíveis/química , Diclofenaco/química , Durapatita/química , Fotólise , Águas Residuárias/química , Poluentes Químicos da Água/análise , Acetonitrilas/química , Catálise , Cristalização , Monitoramento Ambiental/métodos , Recuperação e Remediação Ambiental , Fluoxetina/química , Oxigênio/química , Preparações Farmacêuticas/análise , Pós , Titânio/química , Raios Ultravioleta , Purificação da Água/métodos
4.
J Chromatogr A ; 1451: 120-126, 2016 06 17.
Artigo em Inglês | MEDLINE | ID: mdl-27208983

RESUMO

A two-dimensional liquid chromatography system coupled to triple quadrupole tandem mass spectrometer (2D LC-MS/MS) was employed for the simultaneously quantification of fluoxetine (FLX) and norfluoxetine (NFLX) enantiomers in human milk by direct injection of samples. A restricted access media of bovine serum albumin octadecyl column (RAM-BSAC18) was used in the first dimension for the milk proteins depletion, while an antibiotic-based chiral column was used in the second dimension. The results herein described show good selectivity, extraction efficiency, accuracy, and precision with limits of quantification in the order of 7.5ngmL(-1)for the FLX enantiomers and 10.0ngmL(-1) for NFLX enantiomers. Furthermore, it represents a practical tool in terms of sustainability for the sample preparation of such a difficult matrix.


Assuntos
Fluoxetina/análogos & derivados , Fluoxetina/análise , Leite Humano/química , Cromatografia Líquida/métodos , Fluoxetina/química , Fluoxetina/metabolismo , Humanos , Proteínas do Leite/isolamento & purificação , Soroalbumina Bovina/química , Estereoisomerismo , Espectrometria de Massas em Tandem/métodos
5.
Environ Sci Pollut Res Int ; 23(12): 11927-36, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26961524

RESUMO

Electron beam irradiation (EBI) has been considered an advanced technology for the treatment of water and wastewater, whereas very few previous investigations reported its use for removing pharmaceutical pollutants. In this study, the degradation of fluoxetine (FLX), an antidepressant marketed as Prozac(®), was investigated by using EBI at FLX initial concentration of 19.4 ± 0.2 mg L(-1). More than 90 % FLX degradation was achieved at 0.5 kGy, with FLX below the detection limit (0.012 mg L(-1)) at doses higher than 2.5 kGy. The elucidation of organic byproducts performed using direct injection mass spectrometry, along with the results of ion chromatography, indicated hydroxylation of FLX molecules with release of fluoride and nitrate anions. Nevertheless, about 80 % of the total organic carbon concentration remained even for 7.5 kGy or higher doses. The decreases in acute toxicity achieved 86.8 and 9.6 % for Daphnia similis and Vibrio fischeri after EBI exposure at 5 kGy, respectively. These results suggest that EBI could be an alternative to eliminate FLX and to decrease residual toxicity from wastewater generated in pharmaceutical formulation facilities, although further investigation is needed for correlating the FLX degradation mechanism with the toxicity results.


Assuntos
Elétrons , Fluoxetina/efeitos da radiação , Poluentes Químicos da Água/efeitos da radiação , Purificação da Água/métodos , Aliivibrio fischeri , Animais , Antidepressivos/análise , Antidepressivos/química , Antidepressivos/toxicidade , Daphnia , Estudos de Viabilidade , Fluoretos/análise , Fluoxetina/análise , Fluoxetina/química , Fluoxetina/toxicidade , Nitratos/análise , Águas Residuárias/análise , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/química , Poluentes Químicos da Água/toxicidade
6.
J Anal Toxicol ; 40(2): 108-16, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26487639

RESUMO

In this article, we proposed a new restricted access molecularly imprinted polymer coated with bovine serum albumin (RAMIP-BSA) to be used in a multidimensional chromatographic system applied for the analysis of six selective serotonin reuptake inhibitors (SSRIs) directly from untreated human plasma samples. Fluoxetine, methacrylic acid and ethylene glycol dimethacrylate were used as the template, functional monomer and cross-linker, respectively. The imprinted polymer was covered with a bovine serum albumin (BSA) layer via the interconnections between the amine groups of the BSA using glutaraldehyde as a cross-linker. The obtained RAMIP-BSA was able to extract the SSRIs directly from the human plasma, while ∼100% of the proteins were excluded from the sample. Selectivity coefficients were calculated for fluoxetine (template) in comparison with venlafaxine, duloxetine, citalopram, fluvoxamine, paroxetine and sertraline, and the values were >1 in all cases, attesting to the presence of binding sites in the imprinted polymer. The method presented analytical ranges from 20 to 500 µg/L and correlation coefficients >0.99 for all of the SSRIs (fluoxetine, venlafaxine, duloxetine, citalopram, fluvoxamine and sertraline). Precision and accuracy presented variation coefficients and relative errors <14.5% and within the range of -19.18 to 3.8%, respectively. In all cases, the apparent recoveries were >85%. The proposed method was able to analyze three samples per hour, and each column was used at least 50 times without any significant changes in its performance.


Assuntos
Impressão Molecular , Polímeros/química , Inibidores Seletivos de Recaptação de Serotonina/isolamento & purificação , Soroalbumina Bovina/química , Extração em Fase Sólida/métodos , Cromatografia Líquida de Alta Pressão , Confiabilidade dos Dados , Fluoxetina/química , Glutaral/química , Humanos , Metacrilatos/química , Inibidores Seletivos de Recaptação de Serotonina/sangue
7.
Sci Total Environ ; 524-525: 354-60, 2015 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-25912531

RESUMO

Fluoxetine (FLX), one of the most widely used antidepressants in the world, is an emergent pollutant found in natural waters that causes disrupting effects on the endocrine systems of some aquatic species. This work explores the total elimination of FLX by sonochemical treatment coupled to a biological system. The biological process acting alone was shown to be unable to remove the pollutant, even under favourable conditions of pH and temperature. However, sonochemical treatment (600 kHz) was shown to be able to remove the pharmaceutical. Several parameters were evaluated for the ultrasound application: the applied power (20-60 W), dissolved gas (air, Ar and He), pH (3-11) and initial concentration of fluoxetine (2.9-162.0 µmol L(-1)). Additionally, the presence of organic (1-hexanol and 2-propanol) and inorganic (Fe(2+)) compounds in the water matrix and the degradation of FLX in a natural mineral water were evaluated. The sonochemical treatment readily eliminates FLX following a kinetic Langmuir. After 360 min of ultrasonic irradiation, 15% mineralization was achieved. Analysis of the biodegradability provided evidence that the sonochemical process transforms the pollutant into biodegradable substances, which can then be mineralized in a subsequent biological treatment.


Assuntos
Fluoxetina/química , Ondas Ultrassônicas , Poluentes Químicos da Água/química , Purificação da Água/métodos , Concentração de Íons de Hidrogênio , Cinética , Temperatura
8.
Int J Food Sci Nutr ; 63(1): 125-8, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21809906

RESUMO

A spectrofluorimetric method for the determination of D,L-N-methyl-3-phenyl-3-[(α,α,α-trifluoro-p-tolyl)oxy]propylamine, fluoxetine (F), in pharmaceuticals was evaluated in the 50.0-500.0 µg ml⁻¹ range. Linearity, sensibility, quantification and detection limit, and precision values are satisfactory. The method does not need pre-treatment and was successfully applied to the determination in pharmaceuticals and chitosan (Ch) solution. Ch has an ability to carry and absorb fat and may eventually be used together with F in slimming diets, and then interactions of Ch-F may occur. This work seeks to study these interactions by monitoring the photophysics of a drug in the presence of Ch. The results warn about the care that must be taken when both compounds are prescribed together.


Assuntos
Quitosana/química , Gorduras na Dieta/metabolismo , Fluoxetina/química , Fluoxetina/isolamento & purificação , Hipolipemiantes/química , Espectrometria de Fluorescência/métodos , Quitosana/farmacologia , Dieta Redutora , Interações Medicamentosas
9.
J Chromatogr A ; 1216(49): 8590-7, 2009 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-19879589

RESUMO

A sensitive, selective, and reproducible in-tube polypyrrole-coated capillary (PPY) solid-phase microextraction and liquid chromatographic method for fluoxetine and norfluoxetine enantiomers analysis in plasma samples has been developed, validated, and further applied to the analysis of plasma samples from elderly patients undergoing therapy with antidepressants. Important factors in the optimization of in-tube SPME efficiency are discussed, including the sample draw/eject volume, draw/eject cycle number, draw/eject flow-rate, sample pH, and influence of plasma proteins. Separation of the analytes was achieved with a Chiralcel OD-R column and a mobile phase consisting of potassium hexafluorophosphate 7.5mM and sodium phosphate 0.25M solution, pH 3.0, and acetonitrile (75:25, v/v) in the isocratic mode, at a flow rate of 1.0 mL/min. Detection was carried out by fluorescence absorbance at Ex/Em 230/290 nm. The multifunctional porous surface structure of the PPY-coated film provided high precision and accuracy for enantiomers. Compared with other commercial capillaries, PPY-coated capillary showed better extraction efficiency for all the analytes. The quantification limits of the proposed method were 10 ng/mL for R- and S-fluoxetine, and 15 ng/mL for R- and S-norfluoxetine, with a coefficient of variation lower than 13%. The response of the method for enantiomers is linear over a dynamic range, from the limit of quantification to 700 ng/mL, with correlation coefficients higher than 0.9940. The in-tube SPME/LC method can therefore be successfully used to analyze plasma samples from ageing patients undergoing therapy with fluoxetine.


Assuntos
Cromatografia Líquida/métodos , Fluoxetina/análogos & derivados , Fluoxetina/química , Microextração em Fase Sólida/métodos , Cromatografia Líquida/instrumentação , Fluoxetina/sangue , Humanos , Polímeros/química , Pirróis/química , Microextração em Fase Sólida/instrumentação , Espectrometria de Fluorescência , Estereoisomerismo
10.
Anal Chim Acta ; 614(2): 201-7, 2008 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-18420052

RESUMO

This article presents a method employing stir bar sorptive extraction (SBSE) with in situ derivatization, in combination with either thermal or liquid desorption on-line coupled to gas chromatography-mass spectrometry for the analysis of fluoxetine in plasma samples. Ethyl chloroformate was employed as derivatizing agent producing symmetrical peaks. Parameters such as solvent polarity, time for analyte desorption, and extraction time, were evaluated. During the validation process, the developed method presented specificity, linearity (R(2)>0.99), precision (R.S.D.<15%), and limits of quantification (LOQ) of 30 and 1.37 pg mL(-1), when liquid and thermal desorption were employed, respectively. This simple and highly sensitive method showed to be adequate for the measurement of fluoxetine in typical and trace concentration levels.


Assuntos
Antidepressivos/sangue , Fluoxetina/sangue , Cromatografia Gasosa-Espectrometria de Massas/métodos , Extração em Fase Sólida/métodos , Adsorção , Desipramina/química , Fluoxetina/química , Ésteres do Ácido Fórmico/química , Cromatografia Gasosa-Espectrometria de Massas/instrumentação , Humanos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Fatores de Tempo
11.
Int J Pharm ; 353(1-2): 160-9, 2008 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-18255241

RESUMO

In this work the complex formed between beta-cyclodextrin (betaCD) and fluoxetine (FLU) was investigated by experimental and computational methods. From Horizontal Attenuated Total Reflectance (HATR) was possible to verify a strong modification in the vibrational modes of betaCD and FLU, indicating interactions between them. The Nuclear Magnetic Resonance (NMR) experiments confirm these interactions through the change in chemical shifts in (1)H spectra, reduction in longitudinal relaxation times values, and the Nuclear Ouverhauser Effect confirm the inclusion of aromatic rings of FLU into the betaCD. The structures of the proposed inclusion compounds were optimized at PM3 semiempirical level of theory. In addition, single point calculations at the Density Functional Theory (DFT) level, using the Becke, Lee, Yang, and Parr functional and 6-31G(d,p) basis set, were used to determine the interaction energy for these structures. The DFT calculations identified the aromatic ring, which contains the CF(3) group as the most stable into the betaCD by an amount of, 11.7 kcal mol(-1), in the gas phase. Polarized continuum model, at the DFT level mentioned, was used to investigate the solvent effect, and the results corroborated the gas phase analysis. A high equilibrium constant (K approximately 6921+/-316) and the stoichiometry, 1:1, were obtained by Isothermal Titration Calorimetry (ITC) experiments.


Assuntos
Fluoxetina/química , beta-Ciclodextrinas/química , Fluoxetina/administração & dosagem , Espectroscopia de Ressonância Magnética , Refratometria , Espectroscopia de Infravermelho com Transformada de Fourier , Termodinâmica , beta-Ciclodextrinas/administração & dosagem
12.
J Sep Sci ; 31(1): 78-85, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18035850

RESUMO

A column switching LC method is presented for the analysis of fluoxetine (FLU) and norfluoxetine (NFLU) by direct injection of human plasma using a lab-made restricted access media (RAM) column. A RAM-BSA-octadecyl silica (C-18) column (40 mm x 4.6 mm, 10 microm) is evaluated in both backflush and foreflush elution modes and coupled with a C-18 lab-made (50 mm x 4.6 mm, 3 microm) analytical column in order to perform online sample preparation. Direct injection of 100 microL of plasma samples is possible with the developed approach. In addition, reduction of sample handling is obtained when compared with traditional liquid-liquid extraction (LLE) and SPE. The total analysis time is around 20 min. A LOQ of 15 ng/mL is achieved in a concentration range of 15-500 ng/mL, allowing the therapeutic drug monitoring of clinical samples. The precision values achieved are lower than 15% for all the evaluated points with adequate recovery and accuracy. Furthermore, no matrix interferences are found in the analysis and the proposed method shows to be an adequate alternative for analysis of FLU in plasma.


Assuntos
Cromatografia Líquida/instrumentação , Cromatografia Líquida/métodos , Fluoxetina/análogos & derivados , Fluoxetina/sangue , Fluoxetina/química , Plasma/química , Humanos , Estrutura Molecular
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA