Publications

Nanosensor Technologies for Environmental Monitoring

Electric Properties of Deformable Rubber/CNTs/p-Si Composites under Pressure

Rubbing-in technology was used to fabricate the deformable CNT-p-Si-rubber nanocomposites. The effect of uniaxial compressive displacement (up to ~ 6% of the length of samples) and uniaxial pressure (up to 0.12 kgf/cm2) on the I-V characteristics of the samples were investigated. It was obtained that the I-V characteristics under the effect of displacement or pressure are shifted toward increasing currents at permanent applied voltages. The nonlinearity coefficients of the I-V characteristics slightly reduced due to displacement or pressure and increased with applied voltage. It was observed that the investigated composite samples’ resistances crucially decreased with increase in compressive displacement or pressure. It may be, first of all, due to the decrease in distances between CNT particles in the composite under compression or pressure and the increase in the cross-section area of the samples, accordingly. The composite samples can be used as deformable and shocked-proof pressure and displacement sensors.

Orange-red, green, and blue fluorescence carbon dots for white light emitting diodes

Efficient electrochemical detection and extraction of copper ions using ZnSe–CdSe/SiO2 core–shell nanomaterial

Influence of Additives and Temperature on the Interaction of Acid Red 151 Dye with Cetyltrimethylammonium Bromide: A Conductometric Study

Abstract The interaction of an anionic textile dye, acid red 151 (AR), with a cationic surfactant, cetyltrimethylammonium bromide (CTAB), in aqueous electrolyte medium (e.g., KCl, NaCl) and in H 2 O + ethanol medium was observed using the conductometric method. Two critical micelle concentrations ( CMC ) were found for the AR + CTAB system in water and H 2 O + ethanol medium, but only one CMC was detected for AR + CTAB in salt+H 2 O media and for pure CTAB in all solutions. The change in CMC behavior of CTAB in the presence of AR indicates the occurrence of strong interaction between AR and CTAB. The extent of solubility increases with an increase of temperature, which disfavors micellization. The CMC values in NaCl solution are comparatively lower than those found in KCl solution, which signifies that the micelle formation is more favorable in attendance of NaCl. In aqueous ethanol solution, two CMC values were also observed for AR + CTAB that are higher than those obtained in water. The free energy of micellization ( ) was negative, which illustrates a thermodynamically spontaneous micellization process. The values of enthalpy ( ) and entropy ( ) of micellization show that the process was entirely entropically driven at a lower temperature; but, enthalpic events are favored at elevated temperature in electrolyte medium, whereas both enthalpy and entropy are reduced in attendance of ethanol. In aqueous medium, the thermodynamic parameters signify the presence of electrostatic interaction between AR and CTAB at higher temperatures, while the hydrophobic interaction is the main driving force at a lower temperature. A linear expression of as a function of demonstrates enthalpy‐entropy compensation over the experimental conditions employed in this study.

Clouding Behavior of Amphiphilic Drug Clomipramine Hydrochloride with Pharmaceutical Excipients

Abstract The clouding behavior of amphiphilic drug clomipramine hydrochloride (CLP) in presence of different additives like bile salts, hydrotropes (anionic, cationic and nonionic), fatty acids, sugars and cyclodextrin has been investigated. These additives are commonly used as drug delivery systems. The additives like anionic hydrotropes, bile salts and fatty acid salts increase the cloud point ( CP ) of CLP, when added in low concentrations, whereas at high concentration, decrease it. Cationic and nonionic hydrotropes increase the CP of CLP at all concentrations. All sugars decreased the CP because of their water structure making property. β-cyclodextrin behaves like simple sugar and decreases the CP of the drug solutions. The thermodynamic parameters are also evaluated: where Δ G c° is found to be negative and Δ H c° and T Δ S c° values are negative as well as positive depending upon type and nature of additive.

Improved desalination by polyamide membranes containing hydrophilic glutamine and glycine

Palladium-catalyzed bisfunctionalization of active alkenes by β-acetonitrile-α-allyl addition: application to the synthesis of unsymmetric 1,4-di(organo)fullerene derivatives

Microwave-Assisted Synthesis of Biotin Conjugates with Quinolone Antibiotics via Amino Acids

Benzotriazole-activated biotin was utilized as a versatile building block for the efficient and convenient synthesis of novel biotin conjugates with quinolone antibiotics via amino acid linkers under microwave irradiation. The products are obtained in yields of 70–91% with retention of chirality.

CCDC 1034522: Experimental Crystal Structure Determination

An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.

Cytotoxicity Study of Cadmium-Selenium Quantum Dots (Cdse QDs) for Destroying the Human HepG2 Liver Cancer Cell

In this approach, Hepatocellular carcinoma (HCC) is originated from hepatocytes cell, which can spread several parts in the body. It increases the death rate of cancer patients and more common in men rather than female. Patients having large tumor are growing through expensive treatment such as chemotherapy, radiotherapy and surgery. Nano medicine such as nano-dimensional particles as well as quantum dots might be an alternative treatment with greater efficiency in cancer biology field. Modification of surface and chemical properties of cadmium groups quantum dots can easily penetrate into the cancer cell without harming normal tissues. Here, Cadmium-Selenium Quantum Dot nanomaterials (CdSe QDs) have been prepared in solution phase with 0.1 M concentration, which was potentially applied for the destroying of HepG2 cancer cell with 24 hour and 36 hour of incubation. Due to their size, surface properties, lower cost, QDs can easily attached to the cell and able to damage the cells more rapidly <i>in vitro</i> process. For cell death, gene expression and morphological changing analysis were completed MTT, Flow Cytometry, qRT-PCR assay. Finally, the cell deaths were observed by cell shrinkage, rupture of membrane and expression of apoptotic gene (Bcl2, Beta catenin, Bax) were positive comparing untreated HepG2 cell line.

An efficient synthesis, structural (SC-XRD) and spectroscopic (FTIR, 1HNMR, MS spectroscopic) characterization of novel benzofuran-based hydrazones: An experimental and theoretical studies

Diastereoselective Synthesis of Methanopyridoxazocinones

Two approaches to the synthesis of oxygen-bridged tetrahydropyridones have been developed. In the first approach, substituted pyrido[4,3-<i>g</i>][1,3]oxazocines derivatives were prepared by diastereoselective one-pot reactions of substituted 7-azacoumarins with enolizable ketones and non-bulky primary amines. In the second one, 3-amido-7-azacoumarins were reacted with enolizable ketones in the presence of a base to form diastereomerically pure pyrido[4,3-<i>g</i>][1,3]oxazocines.

Spasmolytic and Ca⁺⁺ Channel Blocking Potential of Nepetolide: Isolated from <i>Nepeta Suavis</i>

Nepeta suavis is used in traditional medicine for treatment of abdominal spasm (colic). The tricyclic clerodane type diterpene, nepetolide, isolated for the first time from Nepeta suavis, was evaluated for Ca++ antagonist and antispasmodic activities. When studied in isolated rabbit jejunum, nepetolide caused concentration-dependent (0.03-100 μM) relaxation of spontaneous and high K+ (80 mM)-induced contractions, like that caused by verapamil, indicating that nepetolide exhibits spasmolytic activity, possibly mediated through Ca++ channel blocking action, which provides scientific explanation for the medicinal application of Nepeta suavis as an antispasmodic agent.

Functionalized Graphene Aerogel

CCDC 872569: Experimental Crystal Structure Determination

An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.

Hiponatremia e hipokalemia graves, recientes, asociadas a hidroclorotiazida, enalaprila y citalopram.: Caso clínico

We report a 72 years old hypertensive female, treated with enalapril 10 mg/day and hydrochlorothiazide 25 mg/day during three years. She presented a depressive disorder and cytalopram was prescribed in a dose of 10 mg/day. Two weeks before admission, a serum electrolyte analysis disclosed normal results and the cytalopram dose was increased to 20 mg/day. The patient was admitted with a hyponatremic encephalopathy with a plasma sodium of 100 mEq/L and a plasma potassium of 2.0 mEq/L. Cytalopram, enalapril and hydrochlorothiazide were discontinued, hypertonic NaCl and KCl were administered. The patient had a favorable evolution with a remarkable improvement of her symptoms.

Phytosynthesis of silver nanoparticles; naked eye cellulose filter paper dual mechanism sensor for mercury ions and ammonia in aqueous solution