RESUMO
In this study, six different organo-hydrogels containing agar-glycerol (AG)-based garlic oil (GO) were synthesized using two different crosslinkers (N,N, methylenebisacrylamide (MBA), glutaraldehyde (GA)) to ensure the controlled release of ceftriaxone (Ce) and carboplatin (Cp). Synthesized organo-hydrogels were characterized by FT-IR. Afterward, swelling behaviors were investigated in DI, tap water, ethanol, acetone, ethanol/DI water (1:1), acetone/DI water (1:1) and gasoline environments and different pH. As a result of hemolysis, blood clotting and antioxidant analysis, organo-hydrogels have been shown to have blood compatibility and antioxidant properties. Ce and Cp release properties of the prepared organo-hydrogels were also determined. The highest Ce release rate was obtained to be 37.8% for p (AG-g-GO)3 at pH 8.0 after 7 days. However, the highest Cp release rate was found to be 95.4% for p (AG-g-GO)3 at pH 7.4 after 1 day.
RESUMO
In this study, a highly sensitive and selective sample pretreatment procedure using molecularly imprinted silica nanoparticles was developed for the extraction and determination of quercetin in red wine samples coupled with high-performance liquid chromatography with ultraviolet detection. The imprinted silica nanoparticles were prepared in the presence of N-acryoyl-l-aspartic acid (functional monomer), quercetin (template), azobisisobutyronitrile (initiator) and methylene bisacrylamide (cross-linker) and methanol/water (porogen) via surface-initiated reversible addition-fragmentation chain transfer polymerization. Surface characterization was performed and several imprinting parameters were investigated, and the results indicated that adsorption of quercetin on the imprinted silica nanoparticles followed a pseudo-first-order adsorption isotherm with a maximum adsorption capacity at 26.4 mg/g within 60 min. The imprinted silica nanoparticles also showed satisfactory selectivity towards quercetin as compared with its structural analogues. Moreover, the imprinted nanoparticles preserved their recognition ability even after five adsorption-desorption cycles. Meanwhile, the nanoparticles were successfully applied to selective extraction of quercetin from red wine with a high recovery (99.7-100.4%). The limit of detection was calculated to be 0.058 µg/mL with a correlation coefficient 0.9996 in the range of 0.2-50 µg/mL. As a result, the developed selective extraction method using molecular imprinting technology simplifies the sample pretreatment procedure before determination of quercetin in real samples.
Assuntos
Impressão Molecular , Nanopartículas/química , Quercetina/análise , Raios Ultravioleta , Vinho/análise , Adsorção , Cromatografia Líquida de Alta Pressão , Estrutura Molecular , Espectrofotometria UltravioletaRESUMO
Magnetic molecularly imprinted nanoparticles were prepared through surface-initiated reversible addition fragmentation chain transfer polymerization by using metronidazole as a template. The molecularly imprinted magnetic nanoparticles were characterized by attenuated total reflection Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, transmission electron microscopy, X-ray diffraction, and vibrating sample magnetometry. The adsorption characteristics were also investigated and the kinetics of the adsorption of metronidazole on the imprinted nanoparticles were described by the second-order kinetic model with the short equilibrium adsorption time (30 min). The adsorption isotherm was well matched with the Langmuir isotherm in which the maximum adsorption capacity was calculated to be 40.1 mg/g. Furthermore, the imprinted magnetic nanoparticles showed good selectivity as well as reusability even after six adsorption-desorption cycles. The imprinted magnetic nanoparticles were used as a sorbent for the selective separation of metronidazole from human serum. The recoveries of metronidazole from human serum changed between 97.5 and 99.8% and showed similar sensitivity as an enzyme-linked immunoassay method. Therefore, the molecularly imprinted magnetic nanoparticles might have potential application for the selective and reliable separation of metronidazole from biological fluids in clinical applications.
RESUMO
In this work, microgels based on tris(2-aminoethyl) amine (TAEA) and glycerol diglycidyl ether (GDE) via simple microemulsion polymerization was prepared as p(TAEA-co-GDE) microgels were used as adsorbent for removal of dichromate (Cr (VI)) and arsenate (As (V)) ions from different aqueous environments. The p(TAEA-co-GDE) microgels were demonstrated very efficient adsorption capacity for Cr (VI), and As (V) that are 164.98 mg/g, and 123.64 mg/g from distilled (DI) water, respectively. The effect of the medium pH on the adsorption capacity of p(TAEA-co-GDE) microgels for Cr (VI) and As (V) ions were investigated. The maximum adsorption capacity was obtained at pH 4.0 for both ions with maximum adsorbed amounts of 160.62, and 98.72 mg/g, respectively. In addition, the microgels were also shown moderate adsorption capacity for Cr (VI) and As (V) from other water sources; tap water with 115.18 mg/g and 82.86 mg/g, sea water with 64.24 mg/g and 46.88 mg/g and creek water with 73.52 mg/g and 59.33 mg/g, respectively. Moreover, the increase in adsorbent dose from 0.025 to 0.125 g enhanced % adsorption of Cr (VI) from 54.13 to 98.03, and As (V) from % 26.72-98.70, respectively. For the adsorption process Langmuir and Freundlich adsorption isotherms were applied and found that Langmuir adsorption isotherm with R2 value of 0.99 for both the metal ions are suitable. Moreover, the experimental adsorption capacities of Cr (VI) and As (V) were found very close to the theoretical values calculated from Langmuir adsorption isotherm. More importantly, the microgels were made magnetic responsive to recover them easily from adsorption medium for reuse studies by applying external magnetic field with little decrease in adsorption capacity. Additionally, reusability of p(TAEA-co-GDE) microgels was also evaluated for adsorption of Cr (VI) and As (V) from DI water.
Assuntos
Arseniatos , Poluentes Químicos da Água , Adsorção , Aminas , Cromo , Glicerol , Concentração de Íons de Hidrogênio , ÍonsRESUMO
Hydrogels are resourceful materials and can be prepared in different morphology, size, surface charge and porosity adopting different polymerization techniques and reaction conditions. The cationic poly(3-acrylamidopropyl)trimethylammonium chloride (p(APTMACl)) microgels were synthesized by photo-initiated inverse suspension polymerization technique. These microgels were utilized as absorbents for the removal of toxic arsenate (As) from different aqueous environments. The experimental parameters affecting absorption efficiency were investigated, and it was demonstrated that these types of microgels are highly efficient in removing arsenate anions from different aqueous environments compared to the previously reported bulk hydrogel, and cryogel of the same material. A removal efficiency of approximately 97.25% was obtained by immersing 0.5 g microgel in 250 ppm 100 mL solution of arsenate anions for 60 min. Both Langmuir and Freundlich adsorption isotherms were applied to adsorption of arsenate anions by p(APTMACl) microgels, and the Langmuir isotherm was a better representation of the adsorption of arsenate with a high value of R(2) (0.9982). Furthermore, mag-p(APTMACl) microgels were synthesized for the adsorption of arsenate anions to provide easy removal of the microgel composite by using an externally applied magnetic field. Furthermore, re-usability of the p(APTMACl) microgels was also investigated for the adsorption of arsenate anions.
Assuntos
Resinas Acrílicas/química , Arseniatos/química , Hidrogéis/química , Compostos de Amônio Quaternário/química , Poluentes Químicos da Água/química , Purificação da Água/métodos , Adsorção , Arseniatos/análise , Cátions , Porosidade , Água , Poluentes Químicos da Água/análiseRESUMO
Cationic poly(Acrylonitril-co-Acrylamidopropyl-trimethyl Ammonium Chloride) (p(AN-co-APTMACl)) hydrogels in bulk were synthesized by using acrylonitrile (AN) and 3-acrylamidopropyl-trimethyl ammonium chloride (APTMACl) as monomers. The prepared hydrogels were exposed to amidoximation reaction to replace hydrophobic nitrile groups with hydrophilic amidoxime groups that have metal ion binding ability. Those replacements were increased the hydrogels absorption capacity for As(V) and Cr(VI). Langmuir and Freundlich isotherms equations were utilized to obtain the best-fitted isotherm model for the absorption of the ions at different metal ion concentrations. The absorption data of As(V) ion were fitted well to Freundlich isotherm while those of Cr(VI) and Cr(III) ions were fitted well to Langmuir isotherm. The maximum absorption of poly(3-acrylamidopropyl-trimethyl ammonium chloride (p(APTMACl)) and amid-p(AN-co-APTMACl) macro gels were 22.39 mg and 21.83 mg for As(V), and 30.65 mg and 18.16 mg for Cr(VI) ion per unit gram dried gel, respectively. Kinetically, the absorption behaviors of Cr(III) and Cr(VI) ions were fitted well to a pseudo 2nd-order kinetic model and those of As(V) ions were fitted well to a pseudo 1st order kinetic model.
Assuntos
Resinas Acrílicas/química , Arseniatos/isolamento & purificação , Cloretos/isolamento & purificação , Compostos de Cromo/isolamento & purificação , Dicromato de Potássio/isolamento & purificação , Compostos de Amônio Quaternário/química , Poluentes Químicos da Água/isolamento & purificação , Purificação da Água/métodos , Absorção Fisico-Química , Resinas Acrílicas/síntese química , Arseniatos/química , Cloretos/química , Compostos de Cromo/química , Hidrogéis , Cinética , Dicromato de Potássio/química , Compostos de Amônio Quaternário/síntese química , Poluentes Químicos da Água/químicaRESUMO
Exploring optimum and cost-efficient medium composition for microbial growth of Candida intermedia Y-1981 yeast culture growing on whey was studied by applying a multistep response surface methodology. In the first step, Plackett-Burman (PB) design was utilized to determine the most significant fermentation medium factors on microbial growth. The medium temperature, sodium chloride and lactose concentrations were determined as the most important factors. Subsequently, the optimum combinations of the selected factors were explored by steepest ascent (SA) and central composite design (CCD). The optimum values for lactose and sodium chloride concentrations and medium temperature were found to be 18.4 g/L, 0.161 g/L, and 32.4°C, respectively. Experiments carried out at the optimum conditions revealed a maximum specific growth rate of 0.090 1/hr; 42% of total lactose removal was achieved in 24 h of fermentation time. The obtained results were finally verified with batch reactor experiments carried out under the optimum conditions evaluated.
Assuntos
Biomassa , Candida/crescimento & desenvolvimento , Candida/citologia , Meios de Cultura/química , Meios de Cultura/farmacologiaRESUMO
In this study, it was aimed to investigate the synthesis, characterization and drug release behaviors of organo-hydrogels containing pH-sensitive Agar (A), Glycerol (G), Sweet Almond oil (Wu et al. in J Mol Struct 882:107-115, 2008). Organo-hydrogels, which contained Agar, Glycerol and different amounts of Sweet Almond oil, were synthesized via the free-radical polymerization reaction with emulsion technique using glutaraldehyde or methylene bis acrylamide crosslinkers. Then, the degree of swelling, bond structures, blood compatibility and antioxidant properties of the synthesized organo-hydrogels were examined. In addition, Organo-hydrogels which loaded with Ceftriaxone and Oxaliplatin were synthesized with the same polymerization reaction and release kinetics were investigated. In vitro release studies were performed at media similar pH to gastric fluid (pH 2.0), skin surface (pH 5.5), blood fluid (pH 7.4) and intestinal fluid (pH 8.0), at 37 °C. The effects on release of crosslinker type and sweet almond oil amount were investigated. Kinetic parameters were determined using release results and these results were applied to zero and first-order equations and Korsmeyer-Peppas and Higuchi equations. Diffusion exponential was calculated for drug diffusion of organo-hydrogels and values consistent with release results were found.
RESUMO
4-vinyl pyridine (4-VP) based hydrogels with 2-hydroxyethylmetacrylate (HEMA) and magnetic composites were prepared and tested for use in the removal of UO(2)(2+) and Th(4+) ions from aqueous environments. It was found that the absorption of these metal ions from aqueous environments decreased with an increase in the amount of HEMA contained within p(4-VP-co-HEMA) hydrogels between 0.498 mmol for pure p(4-VP) and 0.027 mmol for pure p(HEMA). The characterization of the hydrogels was determined by swelling experiments, FT-IR and thermal analysis. The effects of initial metal ion concentration, hydrogel amount and the temperature of the medium on absorption of the ions were investigated. Langmuir and Freundlich isotherms were constructed for the absorption of UO(2)(2+) and Th(4+). Both isotherms demonstrated that these metal ions complied with monolayer absorption kinetics.
Assuntos
Piridinas/química , Tório/química , Compostos de Urânio/química , Purificação da Água/métodos , Absorção , Recuperação e Remediação Ambiental/métodos , Hidrogéis , Magnetismo , Metacrilatos/química , Temperatura , Tório/análise , Compostos de Urânio/análiseRESUMO
The very recent Covid-19 pandemic has made the need to understand biocompatible polymers as support material in drug delivery systems and controlled release clearer, especially for organo-hydrogels. This study aims to synthesize various new polymeric materials called gels, hydrogels, and organo-hydrogels according to the monomer used and to investigate their use as drug release systems. The agar-glycerol (AG) pair was used to synthesize the polymers, N, N, methylene bisacrylamide (MBA, m) and glutaraldehyde (GA, g) were used as cross-linkers and peppermint oil (PmO) was included to obtain the organo-hydrogels. Therefore, one AG gel and two p (AG-m) and p (GA-g) hydrogels were synthesized within the scope of the study. Six different organo-hydrogels based on p(AG-m-PmO) or p (AG-g-PmO) were also synthesized by varying the amount of peppermint oil. Paracetamol and carboplatin were selected as the sample drugs. Synthesized gels, hydrogels and organo-hydrogels were characterized by FTIR and SEM analysis. Additionally, swelling behaviors of the synthesized gels were investigated in different media (ID water, tap water, ethanol, acetone, ethanol/ID water (1:1), acetone/ID water (1:1) and gasoline) and at different pHs. Moreover, it was determined that organo-hydrogels were blood compatible and had antioxidant properties based on hemolysis, blood clotting and antioxidant analysis. Therefore, the release of paracetamol (a known antipyretic-painkiller, recommended and used in the treatment of Covid-19) and carboplatin (widely used in cancer treatment) were studied. Evidently, as the amount of PMO oil increases, the -OH groups in organo-hydrogels will increase and the chemical and physical bonding rates will increase; therefore it was observed that increasing peppermint oil in the organo-hydrogels structure to 0.3 mL stimulated the release of the drugs. For instance, maximum paracetamol release amount from p(AG-g-PmO) and p(AG-m-PmO) organo-hydrogels was calculated to be 72.3% at pH 7.4 and 69.8% at pH 2.0, respectively. The maximum carboplatin release amount from p(AG-g-PmO) and p(AG-m-PmO) organo-hydrogels was calculated to be 99.7% at pH 7.4 and 100% at pH 7.4, respectively. It was concluded that the synthesized organo-hydrogels might easily be used as drug carrier and controlled drug release materials.
Assuntos
Ágar/síntese química , Portadores de Fármacos/química , Liberação Controlada de Fármacos , Glicerol/síntese química , Hidrogéis/síntese química , Óleos de Plantas/síntese química , Acetaminofen/farmacologia , Antioxidantes/análise , Coagulação Sanguínea , Carboplatina/farmacologia , Hemólise , Humanos , Concentração de Íons de Hidrogênio , Cinética , Mentha piperita , Fenóis/análise , Espectroscopia de Infravermelho com Transformada de FourierRESUMO
A novel molecularly imprinted polymer was synthesized on magnetic halloysite nanotube via surface initiated reversible addition-fragmentation chain transfer polymerization in the presence of 2-aminoethylmethacrylamide, 2-Cyano-2-propyl benzodithioate, ethylene glycol dimethacrylate (EGDMA) and azobis(isobutyronitrile) for sensitive and selective spectrophotometric determination of metoclopramide in urine samples. The synthesized imprinted polymer was characterized by several surface characterization techniques and the results indicated there was a thin polymer network on the magnetic halloysite nanotube. The rebinding properties of the molecularly imprinted magnetic halloysite nanotube were also investigated in detail and the maximum adsorption capacity and imprinting factor were found to be 37.8â¯mg/g and 4.51, respectively. The application of the proposed method was carried out by enrichment and spectrophotometric determination of metoclopramide via formation of a charge transfer complex between picric acid and eluted metoclopramide. Under the optimized conditions, the calibration curve was linear in the concentration range of 5.0-150.0â¯ng/mL and the limit of detection and the limit of quantification were calculated to be 1.5â¯ng/mL and 4.95â¯ng/mL, respectively. The inter-day and intra-day precisions were below 5% and recoveries were between 92.8% and 99.2%. The results showed that the proposed method increased the sensitivity and selectivity for spectrophotometric determination of metoclopramide.
Assuntos
Metoclopramida/urina , Impressão Molecular/métodos , Nanotubos/química , Polímeros/química , Espectrofotometria/métodos , Adulto , Humanos , Masculino , Espectroscopia Fotoeletrônica , PolimerizaçãoRESUMO
Response surface methodology (RSM) was successfully applied to enzymatic bio-transformation of 1-naphthol. The experiments were conducted in a closed system containing acetone and sodium acetate buffer, with laccase enzyme. Laccase enzyme used as catalyst was derived from Trametes versicolor (ATCC 200801). The enzymatic bio-transformation rate of 1-naphthol, based on measurements of initial dissolved oxygen (DO) consumption rate in the closed system, was optimized by the application of RSM. The independent variables, which had been found as the most effective variables on the initial DO consumption rate by screening experiments, were determined as medium temperature, pH and acetone content. A quadratic model was developed through RSM in terms of related independent variables to describe the DO consumption rate as the response. Based on contour plots and variance analysis, optimum operational conditions for maximizing initial DO consumption rate, while keeping acetone content at its minimum value, were 301 K of temperature, pH 6 and acetone content of 7% to obtain 9.17 x 10(-3) mM DO/min for initial oxidation rate.
Assuntos
Biodegradação Ambiental , Biotecnologia/métodos , Biotransformação , Lacase/química , Acetona/química , Catálise , Concentração de Íons de Hidrogênio , Cinética , Modelos Estatísticos , Naftóis/química , Oxirredução , Oxigênio/química , Consumo de Oxigênio , TemperaturaRESUMO
At present, commercial pure Titanium (Ti) and microstructured pre-alloyed Titanium-Nickel (TiNi) powders are employed as a sensitive electrochemical hydrogen peroxide (H2O2) sensor. Surface characterization of these materials are performed by x-ray diffraction (XRD) and scanning electron microscopy (SEM). The electrochemical characterization is achieved via cyclic voltammetry (CV), chronoamperometry (CA), and electrochemical impedance spectroscopy (EIS) on Ti and TiNi modified glassy carbon electrode (GCE). The electrochemical behavior of H2O2 at the pure Ti/GCE and microstructure pre-alloyed TiNi/GCE are studied by CV in 0.1â¯M phosphate buffer solution (PBS) containing as the supporting electrolyte. In addition, CA is employed for the determination of H2O2 at the applied potential of 0â¯V vs. Ag/AgCl. The sensor has a linear response range of 0.5-17.5â¯mM with a sensitivity of 280⯵Aâ¯mM-1â¯cm-2. Moreover, the limit of detection (LOD) and limit of quantification (LOQ) are 0.5⯵M and 1.7⯵M, respectively. The electrochemical sensor exhibits fast and selective responses to H2O2 concentration. The applicability of the sensor is checked using a hair coloring as a real sample with satisfactory results.
Assuntos
Técnicas Eletroquímicas/métodos , Peróxido de Hidrogênio/análise , Níquel/química , Titânio/química , Catálise , Eletrodos , Tinturas para Cabelo/análise , Limite de Detecção , Nanoestruturas/química , Nanoestruturas/ultraestrutura , PósRESUMO
The electrochemical oxidation of water-based paint wastewater was investigated batch-wise in the presence of NaCl electrolyte with carbon electrodes for the first time in literature. The electrochemical treatment conditions were optimized using response surface methodology where potential difference, reaction temperature and electrolyte concentration were to be minimized while chemical oxygen demand (COD), color and turbidity removal percents and initial COD removal rate were maximized at 100% pollution load. The optimum conditions were satisfied at 35 g/L external electrolyte concentration, 30 degrees C reaction temperature and 8 V potential difference (64.37 mA/cm(2) current density) realizing 51.8% COD and complete color and turbidity removals, and 3010.74 mg/Lh initial COD removal rate. According to these results, the electrochemical method could be a strong alterative to conventional physicochemical methods for the treatment of water-based paint wastewater.
Assuntos
Eletroquímica/métodos , Recuperação e Remediação Ambiental/métodos , Resíduos Industriais/prevenção & controle , Pintura , Indústria Química , Cor , Eletroquímica/normas , Oxirredução , Eliminação de Resíduos Líquidos/métodos , Poluentes Químicos da Água/química , Purificação da Água/métodosRESUMO
Gum Arabic (GA) microgels were successfully prepared via reverse micellization method with high yield (78.5±5.0%) in 5-100µm size range using divinyl sulfone (DVS) as a crosslinker. The GA microgels were degraded hydrolytically 22.8±3.5% at pH 1 in 20days, whereas no degradation was observed at pH 7.4 and pH 9 at 37°C. By using diethylenetriamine (DETA), and taurine (TA) as chemical modifying agents, GA microgels were chemically modified as GA-DETA and GA-TA, and the zeta potential values of 5.2±4.1 and -24.8±1.3mV were measured, respectively in comparison to -27.3±4.2mV for GA. Moreover, blood compatibility of GA, GA-TA, and GA-DETA microgels was tested via in vitro protein adsorption, % hemolysis ratio, and blood clotting index. All the microgels were hemocompatible with% hemolysis ratio between 0.23 to 2.05, and the GA microgels were found to be highly compatible with a blood clotting index of 81±40. The biocompatibility of GA, GA-DETA and GA-Taurine microgels against L929 fibroblast cells also revealed 84.4, 89.1, and 67.0% cell viability, respectively, at 25.0µg/mL concentration, suggesting great potential in vivo biomedical applications up to this concentration. In addition, 5 and 10mg/mL minimum inhibition concentrations of protonated GA-DETA microgels (GA-DETA-HCl) were determined against E. coli and S. aureus, respectively.
Assuntos
Antibacterianos/química , Géis/química , Goma Arábica/química , Adsorção , Animais , Apoptose , Coagulação Sanguínea , Linhagem Celular , Escherichia coli/efeitos dos fármacos , Géis/síntese química , Goma Arábica/síntese química , Hemólise , Humanos , Hidrólise , Teste de Materiais , Camundongos , Poliaminas , Soroalbumina Bovina/química , Staphylococcus aureus/efeitos dos fármacos , TaurinaRESUMO
Kluyveromyces marxianus Y-8281 yeast culture was utilized for the biological treatment of deproteinated whey wastewater in a batch system. Removal of lactose was optimized by the utilization of response surface methodology, RSM. The empirical model developed through RSM in terms of effective operational factors of medium pH, temperature, lactose and ammonia concentrations was found adequate to describe the treatment of deproteinated whey. Through the analysis, medium pH and temperature were found to be the most significant factors and an increment in both had a positive effect on lactose utilization, while lactose and ammonia concentrations had the least weight within the ranges investigated. Based on contour plots and variance analysis, optimum operational conditions for maximizing lactose removal were found to be 31 degrees C, 45 g/L whey powder concentration, 4 g/L total ammonium salt concentration and medium pH 6. Under the optimum operating conditions determined, 95% lactose removal was achieved after an 18-h fermentation.
Assuntos
Kluyveromyces/metabolismo , Lactose/metabolismo , Eliminação de Resíduos Líquidos/métodos , Amônia , Laticínios , Concentração de Íons de Hidrogênio , Modelos Teóricos , TemperaturaRESUMO
From a natural polyphenol, Tannic acid (TA), poly(TA) nanoparticles were readily prepared using a single step approach with three different biocompatible crosslinkers; trimethylolpropane triglycidyl ether (TMPGDE), poly(ethylene glycol) diglycidyl ether (PEGGE), and trisodium trimetaphosphate (STMP). P(TA) particles were obtained with controllable diameters between 400 to 800nm with -25mV surface charge. The effect of synthesis conditions, such as the emulsion medium, pH values of TA solution, and the type of crosslinker, on the shape, size, dispersity, yield, and degradability of poly(Tannic Acid) (p(TA)) nanoparticles was systematically investigated. The hydrolytic degradation amount in physiological pH conditions of 5.4, 7.4, and 9.0 at 37.5°C were found to be in the order TMPGDEAssuntos
Anti-Infecciosos/química
, Antioxidantes/química
, Reagentes de Ligações Cruzadas/química
, Nanopartículas/química
, Taninos/química
, Anti-Infecciosos/farmacologia
, Antioxidantes/farmacologia
, Bacillus subtilis/efeitos dos fármacos
, Bacillus subtilis/crescimento & desenvolvimento
, Coagulação Sanguínea/efeitos dos fármacos
, Candida albicans/efeitos dos fármacos
, Candida albicans/crescimento & desenvolvimento
, Cromanos/química
, Preparações de Ação Retardada
, Compostos de Epóxi/química
, Escherichia coli/efeitos dos fármacos
, Escherichia coli/crescimento & desenvolvimento
, Géis
, Hemólise/efeitos dos fármacos
, Humanos
, Concentração de Íons de Hidrogênio
, Hidrólise
, Testes de Sensibilidade Microbiana
, Nanopartículas/ultraestrutura
, Tamanho da Partícula
, Fosfatos/química
, Polimerização
, Propilenoglicóis/química
, Pseudomonas aeruginosa/efeitos dos fármacos
, Pseudomonas aeruginosa/crescimento & desenvolvimento
, Staphylococcus aureus/efeitos dos fármacos
, Staphylococcus aureus/crescimento & desenvolvimento
, Eletricidade Estática
, Taninos/farmacologia
RESUMO
In this study, the synthesis of micron-sized poly(vinylbenzyl chloride) (p(VBC)) beads and subsequent conversion of the reactive chloromethyl groups to double amidoxime group containing moieties by post modification is reported. The prepared beads were characterized by SEM and FT-IR spectroscopy. The amidoximated p(VBC) beads were used as adsorbent for the removal of organic dyes, such as eosin y (EY) and methyl orange (MO), and heavy metals containing complex ions such as dichromate (Cr2O7(2-)) and arsenate (HAsO4(2)(-)) from aqueous media. The effect of the adsorbent dose on the percent removal, the effect of initial concentration of adsorbates on the adsorption rate and their amounts were also investigated. The Langmuir, Freundlich and Temkin adsorption isotherms were applied to the adsorption processes. The results indicated that the adsorption of both dichromate and arsenate ions obeyed the Langmuir adsorption model. Interestingly, it was found that the prepared beads were capable of removing significant amounts of arsenate and dichromate ions from tap and river (Saricay, Canakkale-Turkey) water.
RESUMO
A novel resourceful bulk poly(Tannic Acid) (p(TA)) hydrogel was prepared by crosslinking TA molecules with an epoxy crosslinker, trimethylolpropane triglycidyl ether (TMPGDE), in an autoclave at 90°C for 2h. The obtained p(TA) hydrogels were in disk form and have highly porous morphology. The swelling characteristics of p(TA) hydrogels were investigated in wound healing pH conditions of pH 5.4, 7.4, and 9 at 37.5°C, and the hydrogels showed good swelling and moisture content behavior. Especially, p(TA) hydrogels were found to be sensitive to pH 9 with 1669% maximum swelling. P(TA) hydrogels were completely degraded at pH 9 hydrolytically in 9 days. Total phenol contents and the effects of scavenging ABTS(+) radicals of degraded p(TA) hydrogels at pH 5.4, 7.4, and 9 were evaluated and calculated in terms of gallic acid equivalent and trolox equivalent antioxidant capacity, respectively, and found to be very effective. Moreover, degraded p(TA) hydrogels display strong antimicrobial behavior against gram positive Staphylococcus aureus, Bacillus subtilis, gram negative Pseudomonas aeruginosa bacteria strains and Candida albicans fungus strain. The WST-1 results indicated that bulk p(TA) hydrogels have no cyctotoxicity to the L929 fibroblast cell line in vitro.
Assuntos
Anti-Infecciosos/química , Antioxidantes/química , Materiais Biocompatíveis/química , Biopolímeros/química , Hidrogel de Polietilenoglicol-Dimetacrilato/química , Taninos/química , Anti-Infecciosos/farmacologia , Antioxidantes/farmacologia , Apoptose , Materiais Biocompatíveis/farmacologia , Biopolímeros/farmacologia , Linhagem Celular , Humanos , Hidrogel de Polietilenoglicol-Dimetacrilato/síntese química , Hidrólise , Teste de Materiais , Testes de Sensibilidade Microbiana , TermogravimetriaRESUMO
In this study, we report the preparation of poly(tannic acid) (p(TA)) particles by crosslinking with glycerol diglycidyl ether (GDE) and trimethylolpropane triglycidyl ether (TMPGDE). The p(TA) particles are negatively charged as obtained by the zeta potential measurements, -27mV. P(TA) particles are found to be an effective antioxidant material as 170mgL(-1) of p(TA) particle demonstrated the antioxidant equivalency of 82.5±7.2mgL(-1) of gallic acid (GA), used as standard in Folin-Ciocalteau (FC) method. Additionally, TA and p(TA) particles have a strong antimicrobial effect against Escherichia coli ATCC 8739, Staphylococcus aureus ATCC 6538, and Bacillus subtilis ATCC 6633. Furthermore, p(TA) particles were used as drug delivery materials by using model drugs such as TA itself, and GA in the release studies in PBS at pH7.4 at 37.5°C, and found that p(TA) particles can release 80.8 and 87.4% of the loaded TA and GA, respectively. Interestingly, p(TA) maintained its fluorescent property upon crosslinking of TA units. It is further demonstrated that p(TA) particles are as effective as cisplatin (a cancer drug) against A549 cancerous cells that both showed about 36 and 34% cell viability, respectively whereas linear TA showed 66% cell viability at 37.5µgmL(-1) concentration. Above this concentration p(TA) and cisplatin showed almost the same toxicity against A549 cancerous cells. Additionally, p(TA) particles are found to be much more biocompatible against L929 Fibroblast cells, about 84% cell viability in comparison to linear TA with about 53% at 75µgmL(-1) concentration.