Development of a new magnetic solid-phase extraction method prior to HPLC determination of naproxen in pharmaceutical products and water samples.

In this study, a new magnetic solid phase extraction based on magnetic composite modified with biochar obtained from pumpkin peel was developed for the enrichment and extraction of Naproxen in lake water, tablet and urine samples. The effects of main parameters such as pH, extraction time, amount of adsorbent and sample volume, which affect magnetic solid phase extraction, were investigated. Under optimal conditions, intraday and interday precision values for naproxen were below 5.

The relationship between lymphocyte DNA damage, coronary artery disease, and blood trace elements.

Somatic DNA damage and causative factors (occupational exposures, foods, habits, etc.) are thought to contribute to the pathogenesis of atherosclerosis, although knowledge about their role in coronary artery disease (CAD) is still insufficient. This study aimed to determine the effects of lymphocyte-DNA damage and blood trace element concentrations on CAD.

Development of quantum dot-phthalocyanine integrated G-quadruplex /double-stranded DNA biosensor.

In the present study, the phthalocyanine (Pc) integrated mercaptopropionic acid capped quantum dot (mpa@QD) biosensor has been developed for the quantitative determination of G-quadruplex and double-stranded DNA. The working principle of the developed biosensor platform is based on the quenching of the emission signal of the mpa@QD in the presence of Pc (closed position) and the recovery of the fluorescence signal in the presence of DNA (open position). The parameters affecting biosensor performance, such as Pc type and concentration, were optimized.

The synthesis and characterization of iron nanoparticles with lemon peel and its use in magnetic solid phase extraction for trace levels of lead (II).

In this study, a new magnetic solid phase extraction method (MSPE) was developed for the enrichment and separation of trace amount Pb(II) on the magnetic nanoparticles synthesized using lemon peel (FeO-LP). The determination of Pb(II) in the samples was performed with inductively coupled plasma mass spectrometry. The FeO-LP was characterized by scanning electron microscopy, X-ray powder diffractometry, Brunauer-Emmett-Teller surface area analysis, and vibration sample magnetometry.

Determination of color additive tartrazine (E 102) in food samples after dispersive solid phase extraction with a zirconium-based metal-organic framework (UiO-66(Zr)-(COOH)).

A new and rapid dispersive solid phase extraction method by using a green-synthesised UiO-66(Zr)-(COOH) (Zr-BTeC) adsorbent with body-centred cubic topology was developed for determination of tartrazine in food samples. Zr-BTeC was used for the first time as an adsorbent for tartrazine. It was synthesised and characterised by X-ray diffraction, scanning electron microscopy, Fourier transform infrared spectroscopy, thermogravimetric analysis, Brunauer-Emmett-Teller surface area analysis, and zeta potential measurements.

Characterization of persimmon fruit peel and its biochar for removal of methylene blue from aqueous solutions: thermodynamic, kinetic and isotherm studies.

The persimmon fruit peel (PFP) and its biochar (PFP-P) were evaluated for removal of methylene blue (MB) from aqueous solutions and characterized in detail. The pyrolysis of the PFP improved carbon content, surface area, and surface electronegativity of the biochar produced. The effect of initial solution pH, initial MB concentration, contact time, and temperature on the biosorption efficiency of MB on the PFP was investigated through the biosorption experiments in a batch system.

Solid-Phase Extraction Method by Magnetic Nanoparticles Functionalized with Murexide for Trace U(VI) from Sea Water Prior to Spectrophotometric Determination.

In this study, magnetic nanoparticles (Fe3O4/SiO2/APTES) functionalized with murexide were used for the determination of uranium(VI) in sea water by spectrophotometric method in perchloric acid medium using Arsenazo-III as chromogenic reagent. The effects of some analytical parameters, such as pH, contact time, and eluent volume, on the recovery of uranium(VI) were examined in synthetic sea water. The optimum conditions were achieved with a 15 min adsorption time and 2 min elution time with 1 mL of 5 mol L-1 HClO4 at pH of 6.

Use of Water Soluble and Phosphorescent MPA-capped CdTe Quantum Dots for the Detection of Urea.

Objectives: To describe a method for the determination of urea in blood serum using urease enzyme and 3-MPA-capped CdTe quantum dots.

Materials And Methods: The method is based on the increase in pH of the solution as a result of the reaction between urea and urease, which causes an increase in the phosphorescence signal of MPA-CdTe quantum dots in the pH range of 2.5-5.

Triethylamine-assisted Mg(OH) coprecipitation/preconcentration for determination of trace metals and rare earth elements in seawater by inductively coupled plasma mass spectrometry (ICP-MS).

In this paper, we report an improved magnesium hydroxide, Mg(OH), coprecipitation method for the determination of 16 trace elements (Al, V, Cr, Mn, Mn, Fe, Co, Ni, Cu, Zn, Ga, As, Se, Sb, Sn and Pb) and 18 rare earth elements (REEs), including Sc, Y, U and Th in seawater and estuarine water samples. The procedure involves coprecipitation of the trace elements and REEs on Mg(OH) upon addition of a small volume of triethylamine (TEA) followed by analysis of the dissolved pellet solutions by inductively coupled plasma mass spectrometry (ICP-MS). Three-step sequential coprecipitation was carried out on 10 mL aliquots of seawater to eliminate the matrix ions and to preconcentrate the analytes of interest into a 1 mL final volume.