Urinary 1-hydroxypyrene is frequently used as a major metabolite and biological indicator of the overall exposure to polycyclic aromatic hydrocarbons. In this study, solid phase extraction was appropriately conditioned with regard to sample pH, sample concentration, loading flow rate, elution solvent, washing solvent, sample volume and sorbent mass. Octadecyl silica cartridge (C<su...

extraction of nickel and its co-extraction with copper from ammoniacal media into emulsion liquid membrane systems (elms) was investigated using lix 84i as the carrier. measurement of the solute stripped in the internal phase of emulsion opened a new dimension in the study of the elm extraction processes. the effect of operating parameters such as feed ph, initial feed concentration, and treat ...

urinary 1-hydroxypyrene is frequently used as a major metabolite and biological indicator of the overall exposure to polycyclic aromatic hydrocarbons. in this study, solid phase extraction was appropriately conditioned with regard to sample ph, sample concentration, loading flow rate, elution solvent, washing solvent, sample volume and sorbent mass. octadecyl silica cartridge (c18) was used as ...

This paper deals with the extraction of L-Theanine containing Aliquat 336 as a carrier and cyclohexane as solvent across bulk liquid membrane. The optimum operation condition are as follows: extraction time of 150 min, initial concentration of theanine in the feed phase is 1.8 g/L, the carrier concentration is 0.5 M, the ion of the receiving phas...

the extraction-separation of lanthanum and europium ions with bis(2-ethylhexyl) phosphoric acid (dehpa) in cyclohexane was improved by adding 12-crown-4 (12c4) to the aqueous phase as a masking agent. in the presence of this crown ether the extraction curve of lanthanum ions versus ph shifts to the higher ph region, while the curve is not influenced for the europium ions. consequently the separ...

this paper deals with the extraction of l-theanine containing aliquat 336 as a carrier and cyclohexane as solvent across bulk liquid membrane. the optimum operation condition are as follows: extraction time of 150 min, initial concentration of theanine in the feed phase is 1.8 g/l, the carrier concentration is 0.5 m, the ion of the receiving phase is 0.2 m nacl of na2hpo4-nah2po4 buffer solutio...

a hydrmetallurgical study based on the extraction of zn and pb from a nigerian sphalerite mineral leached with 4 m hydrochloric acid has been undertaken. triphenylphosphite (tpp) has proved to be very effective for the extraction of zinc. with 2 m tpp and at ambient temperature of 25±2°c; 35.71% and 66.7% of pb and zn were extracted, respectively, into the organic phase within 60 min. the recov...

in this article cloud-point extraction (cpe) was used with chelating agent to extract uranium from aqueous solutions. the methodology used is based on the formation of metal complexes soluble in a micellar phase of surfactant. the metal ions complexes are then extracted into the surfactant-rich phase at a temperature above the cloud-point temperature. the effect of type of surfactants and ligan...

This technical note explains the disadvantages of manual solid phase extraction (SPE) techniques and the benefits to be gained with automatic systems. The note reports on a number of general and highly specific applications using the Sample Preparation Unit OSP-2A.

A simple, inexpensive and sensitive three-phase hollow fiber liquid-phase microextraction (HFLPME) coupled with high performance liquid chromatography (HPLC) with UV detection was successfully developed for determination of trace level of an anti-Histamine drug, fexofenadine, in human plasma and urine. The analyte was extracted into n-octanol that was immobilized in the wall of a porous hollow ...