Inclusão-separação e pre-concentração de dioxina em amostras de sangue são descritas pelo processo de emulsão de nano membrana líquida de inclusão-facilitada. A novidade deste estudo está na aplicação de nano-bastões de calixareno assim como membranas líquidas de emulsão na pre-concentração seletiva e eficiente da dioxina. Para este fim, parâmetros de extração-inclusão de quatro derivados de p-tert-calix[4]areno com sulfonamidas sintetizados previamente foram investigados. As análises por cromatografia gasosa revelaram que sob condições otimizadas de operação, a pre-concentração da dioxina foi melhorada e o método atingiu menores limites de detecção.

Inclusion-separation and preconcentration of dioxin from blood samples were reported by the inclusion-facilitated emulsion liquid membrane process. The novelty of this study is the application of nano-baskets of calixarene as well as emulsion liquid membranes in the selective and efficient preconcentration of dioxin. For this aim, inclusion-extraction parameters of four p-tert-calix[4]arene derivatives sulfonamide moieties previously synthesized were investigated. Analysis by a gas chromatograph revealed that under the optimized operating condition, the preconcentration of dioxin was improved and the method achieved lower limit of detections.

A new sensitive method for determination of salbutamol, as a nutrient repartitioning agent, in livestock is presented to protect the consumers. Eight nano-baskets of p-tert-calix[4]arene bearing di-[N-(X)sulfonyl carboxamide] and di-(1-propoxy) in partial-cone conformation were synthesized and were used to prepare bended phases of HPLC-UV. The new synthesized bonded-phases were characterized and optimized, the bonding interactions of solute and stationary phases were examined and the main interactions were reported. The results revealed that for the best bonded-phase, the LOD and LOQ were 0.02 and 0.06 μg/mL, respectively.

This paper describes the preconcentration of short chain n-alkyl C1-C6 mercaptans in the produced water using the dispersive liquid-liquid microextraction. In the present experiments, 0.8 mL dispersive solvent (acetonitrile) containing 10.0 µL extraction solvent (carbon tetrachloride) was rapidly injected into the samples and followed by centrifuging and direct injection into the gas chromatograph equipped with flame ionization detector. According to the results, dispersive liquid-liquid microextraction gas chromatography flame-ionization detector was successfully used for determination of short chain n-alkyl C1-C6 mercaptans. The parameters affecting the extraction efficiency were evaluated and optimized. Under the optimum conditions, the figures of merits for six short chain n-alkyl C1-C6 mercaptans were determined to be 4.0-100.0 ng/L (n = 6, RSD = 6.8%), 6.0-80.0 ng/L (n = 6, RSD = 11.0%), 2.0-90.0 ng/L (n = 6, RSD = 2.6%), 5.0-120.0 ng/L (n = 6, RSD = 4.4%), 3.0-80.0 ng/L (n = 6, RSD = 9.2%) and 2.0-110.0 ng/L (n = 6, RSD = 6.5%), respectively.