Dispersive liquid-liquid microextraction (DLLME) coupled with high-performance liquid chromatography-variable wavelength detector (HPLC-VWD) was developed for extraction and determination of thiamphenicol (THA) in honey. A mixture of extraction solvent (30 microL 1,1,2,2-tetrachloroethane) and dispersive solvent (1.0 mL of acetonitrile) was rapidly injected into 5.00 mL sample solution for the ...

Microextração líquido-líquido dispersiva (DLLME) utilizando líquido iônico (IL) como solvente extrator foi desenvolvida com uma nova abordagem para a determinação de quatro pesticidas piretróides em amostras ambientais de água e solo. Cromatografia líquida de alto rendimento com detector de UV (HPLC-UV) foi empregada na análise cromatográfica. Este método é rápido, fácil de operar e ambientalme...

This work describes the development of an HPLC-FLD methodology for separation five fluoroquinolones (ciprofloxacin, enrofloxacin, sarafloxacin, norfloxacin and levofloxacin) followed by optimization DLLME process clean-up preconcentration enrofloxacin in samples seawater river water. The mobile phase used chromatographic consisted methanol: phosphate buffer (NaHPO4 H2O 0.04 M pH 3 with H3PO4 85...

In this paper, a simple dispersive liquid-liquid microextraction for the extraction and pre-concentration of formaldehyde in seawater samples followed with spectrophotometric is proposed. Formaldehyde was derivatized in situ with acetyl acetone in the presence of ammonium acetate in a single step. Then it was collected into a mixture of ethanol (disperser solvent) and chloroform (extracting...

A new method of dispersive liquid-liquid microextraction (DLLME) combined with UV-Vis spectrophotometry was proposed for the determination of trace nickel using 2,2'-Furildioxime as chelating and spectrophotometric reagent. In the proposed approach chloroform and ethanol were used as extraction and dispersive solvents, respectively. Some factors influencing the extraction efficiency of nickel a...

A simple and efficient method for speciation and determination of iron in different water samples was developed. The method is based on ionic liquid ultrasound assisted dispersive liquid–liquid microextraction (IL-USADLLME) followed by spectrophotometric determination. Fe(II) is complexed with 2,4,6-tri(2’-pyridyl)-l,3,5-triazine (TPTZ), neutralized through ion pair formation with sodium dodecy...

BACKGROUND AND THE PURPOSE OF THE STUDY Ofloxacin is a quinolone synthetic antibiotic, which acts against resistant mutants of bacteria by inhibiting DNA gyrase. This antibacterial agent is widely used in the treatment of respiratory tract, urinary tract and tissue-based infections, which are caused by Gram-positive and Gram-negative bacteria. In this work, an efficient modified ionic liquid co...

A new, sensitive and fast dispersive liquid-liquid microextraction (DLLME) coupled with micro-solid phase extraction (μ-SPE) was developed for determination of zearalenone (ZEN) in wheat samples. The DLLME was performed using acetonitrile/water (80:20 v/v) as the disperser solvent and 1-octanol as the extracting solvent.  The acetonitrile/water (80:20 v/v) solvent was also used to extract ZEN f...

Background: Aflatoxin B1 is a secondary toxic metabolite produced by several aspergillus species. This study was conducted to determine the presence of aflatoxin in tomato paste samples. Methods: A total of 30 tomato pastes were analyzed for Aflatoxin B1 contamination via HPLC-FLD. Analyte extraction was done by dispersive liquid-liquid microextraction. Results: The limit of detection (LOD) and...