A comparative study on capability of emulsion models for predicting the viscoelastic behavior of ternary polymer blends with core-shell morphology

Rheologica Acta - The goal of this study was to find a way to apply existing constitutive viscoelastic models on ternary polymer blends forming core-shell morphology. An attempt was also made to...     

Improving of Anticancer Activity and Solubility of Cisplatin by Methylglycine and Methyl Amine Ligands Against Human Breast Adenocarcinoma Cell Line

Methylglycine, also known sarcosine, is dramatically used in drug molecules and its metal complexes can interact to DNA and also do cleavage. Hence, to study the influence of methylglycine ligand on biological behavior of metal complexes, two water-soluble platinum (II) complexes with the formula cis-[Pt(NH₃)₂(CH₃-gly)]NO₃ and cis-[Pt(NH₂-CH₃)₂(CH₃-gly)]NO₃ (where CH₃-gly is methylglycine) have been synthesized and characterized by spectroscopic methods, molar conductivity measurements, and elemental analyzes. The anticancer activity of synthesized complexes was tested against human breast adenocarcinoma cell line of MCF7 using MTT assay and results showed excellent anticancer activity with Cc₅₀ values of 126 and 292 μM after 24 h incubation time, for both complexes of cis-[Pt(NH₃)₂(CH₃gly)]NO₃ and cis-[Pt(NH₂-CH₃)₂(CH₃gly)]NO₃, respectively. Also, the interaction between Pt(II) complexes with calf thymus DNA was extensively studied by means of absorption spectroscopy, fluorescence titration spectra displacement with ethidium bromide (EtBr), and circular dichroism studied in Tris-buffer. The obtained spectroscopic results revealed that two complexes can bind to highly polymerized calf thymus DNA cooperatively and denature at micromolar concentrations. The fluorescence data indicate that quenching effect for cis-[Pt(NH₃)₂(CH₃gly)]NO₃ (K_sv?=?9.48 mM^?1) was higher than that of cis-[Pt(NH₂-CH₃)₂(CH₃gly)]NO₃ (K_sv?= 1.98 mM^?1). These results were also confirmed by circular dichrosim spectra. Consequently, docking data showed that cis-[Pt(NH₃)₂(CH₃gly)]NO₃ with more interaction energy binds on DNA via groove binding which is more compatible with experimental results.

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Graphical Abstract ? Two anticancer Pt(II) complexes, cis-[Pt(NH₃)₂(CH₃gly)]NO₃ and cis-[Pt(NH_2?CH₃)₂(CH₃gly)]NO₃, have been synthesized and interacted with calf thymus DNA. Improving solubility of these compounds reduce side effects and increase anticancer activity against human breast cell line. Modes of binding have been studied by electronic absorption, fluorescence, and CD measurements. Results show that both Pt(II) complexes can interact to DNA via groove binding.

     

Homogeneous liquid-liquid microextraction via flotation assistance coupled with gas chromatography-mass spectrometry for determination of myclobutanil in cucumber,tomato, grape,and strawberry using genetic algorithm

Facile and potent homogeneous liquid–liquid microextraction via flotation assistance method (HLLME-FA) combined with gas chromatography-mass spectrometry was proposed for determination of trace amounts of myclobutanil in fruit and vegetable samples. The paramount parameters, such as extraction and homogeneous solvent types and volumes, ionic strength and extraction time were studied. Under optimum conditions, the detection limit of 0.005 ng g^?1, the linear range of 0.05–100 ng g^?1, and the precision of 3.8% were acquired. A three-layer arti?cial neural network (ANN) model was used with 10 neurons and tan-sigmoid function at hidden layer and a linear transfer function at output layer were developed to predict the process. The results indicated that the proposed ANN model could perfectly predict the process with the mean square error of 0.89%. Then genetic algorithm was utilised to optimise the parameters. The proposed procedure showed satisfactory results for analysis of cucumber, tomato, grape, and strawberry.     

Sol–gel synthesis of Mn2O3/Al2O3/SiO2 hybrid nanocomposite and application for removal of organic dye

Journal of Sol-Gel Science and Technology - Nanocomposite of Mn2O3/Al2O3/SiO2 was prepared through an in situ sol–gel process, in which Mn2O3 nanocrystals were dispersed in the silica-alumina...     

Solvent‐free one‐pot synthesis of pyrane derivatives

A straightforward and an efficient method for the synthesis of 2H‐pyrans via the one‐pot, reaction of alkyl bromides, carbon disulfide, secondary amines, activated acetylenes and isocyanides under solvent‐free conditions without using any catalyst at room temperature is reported. The method offers several advantages including high yields of products and an easy work‐up procedure. J. Heterocyclic Chem., (2011).     

Determination of mercury(II) ion by electrochemical cold vapor generation atomic absorption spectrometry.

A technique for determination of mercury is described; it is based on electrolytic reduction of Hg(II) ion on a graphite cathode, the trapping of mercury vapor and its volatilization into a quartz tube aligned in the optical path of an atomic absorption spectrometer. The electrochemical cell consisted of a graphite cathode and an anode operating with constant direct current for the production of mercury atoms. A pre-activated graphite rod was used as the cathode material. The optimum conditions for electrochemical generation of mercury cold vapor (the electrolysis time and current, the flow rate, the type of electrode and electrolyte) were investigated. The characteristic electrochemical data with chemical cold vapor using NaBH4-acid were compared. The presence of cadmium(II), arsenic(III), antimony(III), selenium(IV), bismuth(III), silver(I), lead(II), lithium(I), sodium(I) and potassium(I) showed interference effects which were eliminated by suitable separation techniques. The calibration curve is linear over the range of 5-90 ng ml(-1) mercury(II). The detection limit is 2 ng ml(-1) of Hg(II) and the RSD is 2.5% (n = 10) for 40 ng ml(-1). The accuracy and recovery of the method were investigated by analyzing spiked tap water and river water.     

DNA as a Target for Anticancer Phen-Imidazole Pd(II) Complexes

Imidazole ring is a known structure in many natural or synthetic drug molecules and its metal complexes can interact with DNA and do the cleavage. Hence, to study the influence of the structure and size of the ligand on biological behavior of metal complexes, two water-soluble Pd(II) complexes of phen and FIP ligands (where phen is 1,10-phenanthroline and FIP is 2-(Furan-2-yl)-1H–Imidazo[4,5-f][1, 10]phenanthroline) with the formula of [Pd(phen)(FIP)](NO₃)₂ and [Pd(FIP)₂]Cl₂, that were activated against chronic myelogenous leukemia cell line, K562, were selected. Also, the interaction of these anticancer Pd(II) complexes with highly polymerized calf thymus DNA was extensively studied by means of electronic absorption, fluorescence, and circular dichroism in Tris-buffer. The results showed that the binding was positive cooperation and [Pd(phen)(FIP)](NO₃)₂ (K _f = 127 M^-1 G = 1.2) exhibited higher binding constant and number of binding sites than [Pd(FIP)₂]Cl₂ (K _f = 13 M^-1 G = 1.03) upon binding to DNA. The fluorescence data indicates that quenching effect for [Pd(phen)(FIP)](NO₃)₂ (K _SV = 58 mM^?1) was higher than [Pd(FIP)₂]Cl₂ (K _SV = 12 mM^?1). Also, [Pd(FIP)₂]Cl₂ interacts with ethidium bromide-DNA, as non-competitive inhibition, and can bind to DNA via groove binding and [Pd(phen)(FIP)](NO₃)₂ can intercalate in DNA. These results were confirmed by circular dichroism spectra. Docking data revealed that longer complexes have higher interaction energy and bind to DNA via groove binding.

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Graphical Abstract Two anticancer Pd(II) complexes of imidazole derivative have been synthesized and interacted with calf thymus DNA. Modes of binding have been studied by electronic absorption, fluorescence, and CD measurements. [Pd(FIP)₂]Cl₂ can bind to DNA via groove binding while intercalation mode of binding is observed for [Pd(phen)(FIP)](NO₃)₂.

     

Simultaneous Determination of Deltamethrin and Permethrin in Water Samples Using Homogeneous Liquid–Liquid Microextraction via Flotation Assistance and GC-FID

A new method was developed for the simultaneous determination of deltamethrin and permethrin in water samples with homogeneous liquid–liquid microextraction via flotation assistance and gas chromatography–flame ionization detection. A special extraction cell was designed to facilitate collection of the low density solvent extracts. The sample solution was added into the extraction cell, which contained an appropriate mixture of n-hexane (as an extraction solvent) and acetone (as a homogeneous solvent). Air flotation allowed the extraction solvent to be collected from the top of the solution. Under the optimum conditions, good linearity was observed in the range of 1.0–200 μg L^?1 with a correlation coefficient (r ²) greater than 0.9980 for both of the analytes. The limits of detection were 0.2 and 0.3 μg L^?1 for deltamethrin and permethrin, respectively (S/N = 3). The developed method was successfully applied to determine the two pesticides in three different water samples.     

Determination of dextrose in peritoneal dialysis solution by localized surface plasmon resonance technique based on silver nanoparticles formation

Determination of dextrose in peritoneal dialysis with a method based on silver nanoparticles (AgNPs) formation was investigated. In a green chemistry method, silver nanoparticles (AgNPs) were synthesized in the natural polymeric matrix of gelatin. The nanoparticles were characterized with UV–Vis spectroscopy and transmission electron microscopy (TEM). Absorbance signal of AgNPs could be applied to determine the various concentrations of dextrose solutions. Drop wise and ultrasonic methods were used and compared with each other. The dynamic range of methods with limit of detection and relative standard deviations were obtained. Results for real sample (peritoneal dialysis) were satisfied.