Speciation of alkyllead in aqueous samples with application of liquid membrane probe for extraction and preconcentration

Abstract

Lead is known to be toxic, especially in its organic forms (organolead, OL). In the environment tetraalkyllead species are rapidly degraded by sunlight and atmospheric constituents like ozone or hydroxyl radicals. Such breakdown yields the soluble forms such as trialkyllead and dialkyllead and finally ionic lead species. The liquid membrane extraction probe (LMP) device has been developed and used as an extraction and preconcentration tool for the speciation analysis of organolead compounds by GC/MS. It allows analysis of OL species at low concentrations in complicated matrices of environmental samples. The effect of pH, stirring rate, and time that influence the extraction efficiency of OL extraction by the LMP method were optimized. The transformation of tetramethyllead in aqueous media at different concentrations of major ions K(+), Na(+), Ca(2+), Mg(2+), Cl(-), SO(4)(2-) and the application of LMP to environmental samples are presented. It was found that degradation of tetramethyllead takes between 24 and 37 days. The detection limit (LOD) of the method for all organolead species investigated is around 4.7 microg/L, with a limit of quantitation of 15 microg/L.

Internal Architecture and Adsorption Sites of Violet Lander Molecules Assembled on Native and KBr‐Passivated InSb(001) Surfaces

“…A liquid membrane (LM) method integrated extraction and stripping into a continuous process is also very attractive. This method has been studied for selective separation and concentration of alcohol and phenol 12–14, metal ions 15–18, amino acids and their derivation 19–21, synthetic drugs 22, 23, etc . However, the studies on separation and extraction of bioactive components from traditional herbal medicines with the LM method are lacking due to the complexity of the chemical compositions of herbal medicines 24–27.…”

“…There are three basic forms of LM processes: emulsion LM (ELM) 12, 13, supported LM (SLM) 14, 17, 18, 23, and bulk LM (BLM) 15, 16, 19–22. BLM is characterized by its thick and stable LM layer, which corresponds to a high stability but low transport efficiency.…”

Potential of combining of liquid membranes and molecularly imprinted polymers in extraction of 17β‐estradiol from aqueous samples

“…More time allows E2 to diffuse through the membrane leading to more binding onto MIP particles. It also allows the sample solution to be in contact with the membrane for longer periods [20]. However, at around 60 min, signs of reaching a plateau could be detected.…”

Gas‐diffusion microextraction

“…A SLM extraction probe of similar exterior design was found by the authors while preparing this manuscript 36–38; however, the concept of Cukrowska and co‐workers is based on SLM, which is different from GDME.…”