Rapid and simple determination of gabapentin in urine by ion mobility spectrometry.

Gabapentin is a pharmacological agent used in the treatment of epileptic seizures. In this work, a fast method is proposed for determination of gabapentin in urine by ion mobility spectrometry (IMS) without any extraction and derivatization. ZnCl was used as an effective protein precipitating reagent to remove the urine proteins.

Flax Biomass Conversion via Controlled Oxidation: Facile Tuning of Physicochemical Properties.

The role of chemical modification of pristine linen fiber (LF) on its physicochemical and adsorption properties is reported in this contribution. The surface and textural properties of the pristine LF and its peroxyacetic acid- (PAF) and chlorite-treated (CF) fiber forms were characterized by several complementary methods: spectroscopy (SEM, TEM, FT-IR, and XPS), thermal analysis (DSC and TGA), gas/water adsorption isotherms, and zeta potential (ξ). The results obtained reveal that the surface charge and textural properties (surface area and pore structure) of the LF material was modified upon chemical treatment, as indicated by changes in the biomass composition, morphology, ξ-values, and water/dye uptake properties of the fiber samples.

A Non-linear Viscoelastic Model of the Incudostapedial Joint.

The ossicular joints of the middle ear can significantly affect middle-ear function, particularly under conditions such as high-intensity sound pressures or high quasi-static pressures. Experimental investigations of the mechanical behaviour of the human incudostapedial joint have shown strong non-linearity and asymmetry in tension and compression tests, but some previous finite-element models of the joint have had difficulty replicating such behaviour. In this paper, we present a finite-element model of the joint that can match the asymmetry and non-linearity well without using different model structures or parameters in tension and compression.

Characterization and performance evaluation of functional monomer effect on molecular imprinted polyurethane foam.

Herein we describe a methodology to synthesis polyurethane foam molecularly imprinted polymer (PUF-MIP) by using functional monomer for selective extraction of alprazolam. For this purpose, the various percentages of functional monomer are used to synthesis PUF-MIP of alprazolam. To evaluate the selectivity of synthesized PUF-MIP HPLC analysis is applied by introducing caffeine and methadone as an interference.

Evaluation of an Experimentally Designed Molecular Imprinted Polyurethane Foam Performance for Extraction of Alprazolam.

Industrial polyurethane rigid foam (PUF) was selected as a substrate for selective solid phase extraction of Alprazolam. Effective parameters for raising selectivity of the PUF were evaluated. Synthetic molecularly imprinted polyurethane foam (MIPUF) was tracked as selective adsorbent and its characteristic was pondered by analytical methods.

Fabrication of a nanomaterial-based fluorescence sensor constructed from ligand capped CdTe quantum dots for ultrasensitive and rapid detection of silver ions in aqueous samples.

In this study, CdTe QDs were prepared in aqueous medium and then capped with a synthetic heterocycle ligand (CdTe/L QDs) via surface modification method. Characterization of synthesized CdTe/L QDs was carried out through various analytical techniques including fluorescence spectroscopy, transmission electron microscopy (TEM), UV-Vis spectrophotometry, thermo-gravimetric (TG) analysis and Fourier transform infrared (FTIR). The fluorescence intensity of the CdTe/L QDs at 520 nm (excitation at 380 nm) was selectively quenched in the presence of trace amounts of silver ions.

Synergistic co-delivery of doxorubicin and melittin using functionalized magnetic nanoparticles for cancer treatment: loading and in vitro release study by LC-MS/MS.

In this study, citric acid-functionalized FeO magnetic nanoparticles (CA-MNPs) were prepared via a coprecipitation method and were fully characterized. Doxorubicin (DOX) and melittin (MEL), as anticancer agents, were loaded onto CA-MNPs surface through electrostatic interactions with the aim to achieve an effective co-delivery system for cancer therapy. The loading efficiency and in vitro release profiles of DOX and MEL were investigated by liquid chromatography-tandem mass spectrometry (LC-MS/MS).

Ligand-Capped CdTe Quantum Dots as a Fluorescent Nanosensor for Detection of Copper Ions in Environmental Water Sample.

In this work, as a novel fluorescent nano-sensor, a ligand-capped CdTe QDs (CdTe-L QDs) was designed for the detection and quantification of Cu ions in environmental water samples. The synthesized QDs were characterized by transmission electron microscopy (TEM), thermo-gravimetric (TG) analysis, Fourier transform infrared (FTIR), UV-Vis spectrophotometry and fluorescence spectroscopy. Optical properties of the produced nanosensor were monitored by UV-Vis and fluorescence spectrophotometry.

Capillary Force between Flexible Filaments.

Liquid droplets bridging filaments are ubiquitous in nature and technology. Although the liquid-surface shape and the capillary force and torque have been studied extensively, the effect of filament flexibility is poorly understood. Here, we show that elastic deformation (at large values of the elasto-capillary number) can significantly affect the liquid-surface shape and capillary force.

Bubbles and drops on curved surfaces.

Surface curvature affects the shape, stability, and apparent contact angle of sessile and pendant drops. Here, we develop an approximate analytical solution for non-axisymmetric perturbations to small spherical drops on a flat substrate, assuming a fixed contact angle and fixed drop volume. The analytical model is validated using numerical solutions of the Laplace equation from the Surface Evolver software.

Photoelectrocatalytic degradation of acid dye using Ni-TiO2 with the energy supplied by solar cell: mechanism and economical studies.

This paper reports an investigation into the effect of a number of operating factors on the removal of Acid Red 88 from an aqueous solution through photoelectrocatalysis: photocatalyst dose, dye concentration, pH, bias potential, and electrolyte concentration. The photocatalyst was Ni-TiO2 applied in suspension to the solution to achieve a larger catalyst surface area. The optimum values for photocatalyst dose, dye concentration, and electrolyte concentration turned out to be 0.

A simple and high resolution ion-pair HPLC method for separation and simultaneous determination of nitrate and thiocyanate in different water samples.

An ion-pair reversed-phase high-performance liquid chromatography method with isocratic elution and ultraviolet detection was developed and validated for the separation and simultaneous determination of nitrate and thiocyanate. The separation was performed on a C18 analytical column with mobile phase containing 0.08 mM hexadecyltrimethylammonium bromide as an ion-pair reagent, 40 mM of acetate buffer and 30% methanol at pH 3.

Using a new ligand for solid phase extraction of mercury.

The octadecyl silica cartridge as a sorbent and 4-bp db (1,4-bis(4-pyridyl)-2,3-diaza-1,3-butadiene) as a ligand is a simple, rapid and reliable method for extracting and preconcentrating of Hg(II) in real samples prior to cold vapor atomic absorption spectrometry. Sample solutions were passed through a column at pH 4.5 then retained mercury ions on the column were eluted with minimal amount of 0.

DABTZ as a new reagent for solid phase extraction and spectrophotometric determination of trace amount of Hg(II) in water sample.

A novel sensitive and simple method for rapid and selective extraction, preconcentration and determination of mercury as its 2,2' diamino-4,4' bithiazole (DABTZ) complex by using octadecylsilica cartridges and spectrophotometry is presented. Extraction efficiency and the influence of flow rates of sample solution and eluent, pH, amount of DABTZ, type and least amount of eluent for elution of mercury complex from cartridges, break through volume and limit of detection were evaluated. Also the effects of various cationic and anionic interferences on percent recovery of mercury were studied.