Simultaneous determination of furosemide and carbamazepine in biological matrices by solvent bar microextraction combined with high-performance liquid chromatography-diode array detector and central composite design.

A sensitive and simple sample pretreatment method based on a two-phase solvent bar microextraction (SBME) technique coupled with HPLC-diode array detector (DAD) was developed for simultaneous extraction and determination of trace amounts of furosemide and carbamazepine in human urine and plasma samples. The significance of operational factors on carbamazepine and furosemide extraction efficiency % (EE%) was screened using full factorial design (FFD) while central composite design (CCD) was used to model the entire process. A quadratic model was found convenient to correlate the extraction EE% of selected drugs with dominant experimental factors.

Use of citric acid and garlic extract to inhibit Salmonella enterica and Listeria monocytogenes in hummus.

Recently, the consumption of hummus has become popular in the United States, European countries, and Canada, and unfortunately, several foodborne outbreaks and recalls have been reported due to its contamination with Listeria monocytogenes and Salmonella enterica. The current study aimed to investigate the inhibitory activity of 0.5, 1.

Competitive extraction of Li, Na, K, Mg and Ca ions from acidified aqueous solutions into chloroform layer containing diluted alkyl phosphates.

Alkyl phosphates were extensively used in liquid-liquid extraction of lanthanides and actinides, but to a lesser extent for alkali and alkaline earth metals. The high amount of alkyl phosphate, which is usually used in the organic layer (>40 wt%), is not favoured due to its corrosive effect and toxicity. In the present work, diluted chloroform solutions (20.

Selective removal of dibenzothiophene from commercial diesel using manganese dioxide-modified activated carbon: a kinetic study.

With a total concentration of 7055 mgS/kgfuel, the content of organosulphur compounds (OSCs) in local diesel is 20 times higher than the regulated value. Analysis revealed that 30% of OSC is originated from dibenzothiophene (DBT). It is known that DBT is a hardly removable compound and selective adsorbents are often needed for its removal with low affinity for other diesel components.

Separation and flame atomic absorption spectrometric determination of total chromium and chromium (III) in phosphate rock used for production of fertilizer.

Due to the commercial value of phosphate rock (PR) as a fertilizer precursor, it is necessary to investigate its heavy metals content. Chromium (Cr) may present as Cr(III) or Cr(VI) in PR; but quantitative differentiation between them is not an easy task. This is due to possible interconversion of Cr species during the digestion/leaching process.

A simple and accurate analytical method for determination of three commercial dyes in different water systems using partial least squares regression.

A simple analytical procedure is proposed for simultaneous determination of three common dyes (Basic Blue 9, Brilliant Blue E-4BA, and Reactive Blue 2) in natural waters without prior separation of the solutes. A popular chemometric method, partial least squares regression PLS-1, was effectively applied for spectral resolution of a highly overlapping system. At the best modeling conditions, mean recoveries and relative standard deviations (RSD) for dyes quantification by PLS-1 were found to be 102.

Characteristics of organosulphur compounds adsorption onto Jordanian zeolitic tuff from diesel fuel.

The removal of organosulphur compounds (ORS) from diesel fuel is an important aspect of Jordanian's effort to reduce air pollution. Currently, the total sulphur content in Jordanian diesel fuel is 12,000 ppmw (1.2%, wt/wt), but Jordanian government has recently introduced new restrictions that will reduce this level gradually to internationally acceptable levels.

Application of chemometrics and FTIR for determination of viscosity index and base number of motor oils.

The viscosity index (VI) and the base number (BN) of motor oils are the most important parameters to be measured in order to assess their performance and service time. Both parameters were simply obtained for virgin and recycled motor oil samples using multivariate calibration based on the FTIR data. Analysis showed that the PLS-1 has outperformed CLS and PCR for the oil parameters prediction.

Simultaneous determination of pesticides at trace levels in water using multiwalled carbon nanotubes as solid-phase extractant and multivariate calibration.

The application of solid-phase extraction with multivariate calibration for simultaneous determination of three toxic pesticides in tap and reservoir waters was presented. The proposed analytical method was used for the determination of atrazine, methidathion, and propoxur in complex water samples without the need for chromatographic separation. Among the applied multivariate calibration methods, partial least squares (PLS-1) method was found the most effective for pesticides quantification.

Preparation of highly selective solid-phase extractants for Cibacron reactive dyes using molecularly imprinted polymers.

Selective polymeric extractants were prepared for preconcentration of Cibacron reactive red dye, a dye that is often applied with Cibacron reactive blue and Cibacron reactive yellow for dyeing of fabrics. The best extractant was fabricated (in chloroform) using methacrylic acid (as monomer), ethylene glycol dimethacrylate (as crosslinker), AIBN (as initiator for polymerization), and red dye as template molecule, with a molar stoichiometric ratio of 8.0:40.

Determination of motor gasoline adulteration using FTIR spectroscopy and multivariate calibration.

In this paper, an attempt has been made to develop a feasible procedure for the prediction of quality parameters of motor gasoline and to discriminate between the different adulterated motor gasoline samples using density values, distillation temperatures and Fourier transform infrared (FTIR) analyses along with multivariate calibrations without the need for using chromatographic separation or other expensive instruments such as an octane number analyser. Ten blend mixtures of regular and super motor gasoline were prepared in order to study density, distillation temperatures and FTIR spectra characteristics for each blend. Distillation temperatures for the pure and blend mixtures of regular and super motor gasoline at initial boiling point (IBP) to final boling point (FBP) at 5%Vol.

Solid-phase extraction and simultaneous determination of trace amounts of sulphonated and azo sulphonated dyes using microemulsion-modified-zeolite and multivariate calibration.

A simple and rapid analytical method for the determination of trace levels of five sulphonated and azo sulphonated reactive dyes: Cibacron Reactive Blue 2 (C-Blue, trisulphonated dye), Cibacron Reactive Red 4 (C-Red, tetrasulphonated azo dye), Cibacron Reactive Yellow 2 (C-Yellow, trisulphonated azo dye), Levafix Brilliant Red E-4BA (L-Red, trisulphonated dye), and Levafix Brilliant Blue E-4BA (L-Blue, disulphonated dye) in water is presented. Initially, the dyes were preconcentrated from 250 ml of water samples with solid-phase extraction using natural zeolite sample previously modified with a microemulsion. The modified zeolite exhibited an excellent extraction for the dyes from solution.

Critical evaluation and comparison of enrichment efficiency of multi-walled carbon nanotubes, C18 silica and activated carbon towards some pesticides from environmental waters.

In this work, optimization of multi-residue solid phase extraction (SPE) procedures coupled with high-performance liquid chromatography for the determination of Propoxur, Atrazine and Methidathion from environmental waters is reported. Three different sorbents were used in this work: multi-walled carbon nanotubes (MWCNTs), C18 silica and activated carbon (AC). The three optimized SPE procedures were compared in terms of analytical performance, application to environmental waters, cartridge re-use, adsorption capacity and cost of adsorbent.

Effect of dimensions of multi-walled carbon nanotubes on its enrichment efficiency of metal ions from environmental waters.

The effect of dimensions (length and external diameter) of multi-walled carbon nanotubes (MWCNTs) on its preconcentration efficiency towards some metal ions (Pb2+, Cd2+, Cu2+, Zn2+ and MnO4(-)) from environmental waters prior to their analysis by flame atomic absorption spectroscopy (FAAS) was investigated. MWCNTs (as-received from the manufacturer) of various external diameters and lengths were involved. Other variables optimized included effects of pH of water sample, composition and volume of eluent, mass of the MWCNTs, breakthrough volume and coexisting ions.

Sorption of Zn(II), Pb(II), and Co(II) using natural sorbents: equilibrium and kinetic studies.

Natural Jordanian sorbent (consisting of primary minerals, i.e., quartz and aluminosilicates and secondary minerals, i.