thallium is widely found in nature, but the only inorganic stones full of this element are crookesite and lorandit. it isalso found in pyrites of copper, lead and inorganic stones. the element and its compositions are toxic and harmful to theenvironment; therefore, its application requires caution and further research. it is important to develop sensitive andaccurate analytical methods to deter...

abstract mefenamic acid is a nonsteroidal anti-inflammatory drug (nsaid) that has analgesic,anti-infammatory and antipyretic actions. it is used to relieve mild to moderate pains. solid-phase extraction of mefenamic acid by a polymer grafted to silica gel is reported . poly allyl glycidyl ether/iminodiacetic acid-co-n, n-dimethylacrylamide was synthesized and grafted to silica gel and was used ...

The extraction of caffeine from bioresources using more benign and cost-effective processes is of fundamental relevance towards the finding of alternative (bio)pesticides. Classically, the best attempts to extract caffeine from biomass have resulted in low efficiency and in a large consumption of hazardous organic solvents and/or energy requirements. Here, we report an enhanced and selective ex...

A methodology based on dispersive micro solid-phase extraction (DMSPE) using multiwalled carbon nanotubes (MWCNTs) as solid sorbent prior to measurement with energy-dispersive X-ray fluorescence (EDXRF) spectrometry is proposed. The procedure consists of chelating of nickel, cobalt, copper, and lead ions with ammonium pyrrolidinedithiocarbamate (APDC) and posterior adsorption of metal chelates ...

Ion pair dispersive liquid- liquid microextraction (IP-DLLME) method combined with flame atomic absorption spectrometry was proposed for the determination of trace amounts of copper(II). By using pyrocatechol violet as chelating agent and cetyltrimethyl ammonium bromide as an ion pairing agent, the trace amount of copper(II) was extracted in chloroform. The factors influencing the formation cop...

A convenient solid phase method for extracting and fractionating steroid hormones from serum or urine is presented. The influence of the solvent used for extraction, of the body fluid to be extracted, and of the degree of sample dilution on the efficiency of extraction was studied for progesterone and cortisol. The potency of fractionation was demonstrated by the separation of the steroid pairs...

A simple, rapid and efficient dispersive liquid–liquid microextraction by use of ionic liquid (IL-DLLME)method, followed by flame atomic absorption spectrometry (FAAS) was developed for the preconcentrationand determination of palladium in water samples. In this method, an appropriate mixture of acetone and octylmethyl imidazolium hexafluorophosphate was injected rapidly into the aqueous sample...

Proteins are one the most widely studied biomolecules with diverse functions and applications. Aiming at overcoming current drawbacks of purification processes proteins, introduction ionic liquids (ILs) has been a hot topic research. ILs have applied in creation aqueous biphasic systems (IL-based ABS), solid-phase extractions through poly(ionic liquid)s (PILs) supported ionic-liquid phases (SIL...