A new micell-mediated phase separation method for preconcentration of ultra-trace quantities of cadmium as a prior step to its determination by flame atomic absorption spectrometry has been developed. The method is based on the cloud point extraction (CPE) of cadmium in iodide media with Triton X-114 in the absence of any chelating agent. The optimal extraction and reaction conditions (e.g., ac...

The solid-phase chemiluminescence analysis of gold on the surface of an anion-exchange resin was studied. A method for the fast determination of gold using flow injection was established. The anion-exchange resin was used as an adsorbent of gold ion in the form of AuCl4-. The cation-exchange resin was used for the on-line separation of cations in the matrix. To obtain the best results, the prec...

A new sorbent was synthesized by anchoring 7-amino-4-azaheptyltrimetoxisilane, freshly prepared, to silica gel, producing 7-amino-4-azaheptyl anchored silica gel (AAHSG). This material was characterized by infrared spectroscopy (IR), elemental analysis (CHN), and nitrogen adsorption-desorption isotherms. Isotherms of the adsorption of Fe3+, Fe2+ and Cu2+ on AAHSG were recorded, which indicated ...

A glassy carbon electrode modified with a Nafion/MWCNTs composite is shown to enable the determination of codeine using differential pulse voltammetry in phosphate buffer of pH 3.0. At a preconcentration time of 15 s, the calibration graph is linear in the 0.5 µM (0.15 mg·L(-1)) to 15 µM (4.5 mg·L(-1)) concentration range with a correlation coefficient of 0.998. The detection limit at a preconc...

A simple and sensitive solid phase extraction utilizing C18 filled cartridges incorporated with dithizone for preconcentration of lead and its subsequent determination by flame atomic absorption spectrometry (FAAS) was developed. Several parameters such as type, concentration and volume of eluent, pH of the sample solution, flow rate of extraction and volume of the sample were evaluated. The ef...

A more sensitive flow injection preconcentration method has been developed for the determination of four β-lactam antibiotics (BLAs) namely cefaclor, cefotaxime, amoxicillin and ampicillin in urine, pharmaceuticals and milk. A mini-column packed with PUF functionalized with the cationic polyelectrolyte, poly(N-chloranil N,N,N',N'-tetramethylethylene diammonium dichloride) PCTDD, was utilized fo...

The most essential limitation of batch-injection analysis (BIA) methodology compared to other flow methods (CFA, FIA, SIA) is the lack of possibility of on-line sample processing in the measuring system. Some procedures of on-line sample pretreatment in BIA are possible by changing the plastic tip of the automatic micropipette used for sample injection into a flow-through reactor, e.g. by packi...

A simple and sensitive method for the separation and preconcentration of gold, palladium and platinum has been established prior to their atomic absorption spectrometric determinations. Analytes from 0.5 mol dm(-3) KI in a 2 mol dm(-3) HCl solution were recovered using an Amberlite XAD-7 column as halogeno complexes. The effects of some analytical parameters, including reagent amounts, sample v...

Micellar electrokinetic chromatography (MEKC) using a cationic surfactant as a pseudostationary phase was examined to separate anionic metal cyclohexane-1,2-diaminetetraacetic acid (CDTA) complexes. Cetyltrimethylammonium chloride (CTAC) was employed as the cationic surfactant micelle, its addition leading to EOF reversal. Cu(II), Co(II), Zn(II), Mn(II) and Pb(II) were used as test analytes, an...

a method was developed for removal, preconcentration and spectrophotometric determination of trace amounts of methyl red based on sio2-coated fe3o4magnetic nanoparticles. the influence of ph, dosage of adsorbent and contact time on the adsorption of dye was explored by central composite design. the kinetic data were analyzed based on the langmuir and freundlich adsorption isotherms. the langmui...