A Method for the Determination of Veterinary Drugs from Different Therapeutic Classes in Animal Urine.

A rapid, precise and robust HPLC separation procedure has been developed and optimized for the determination of a series of drugs of different therapeutic classes: chlortetracycline, oxitetracycline, cefoperazone, diclofenac, tiamphenicol, marbofloxacin, ciprofloxacin, danofloxacin, enrofloxacin and flumequine. The chromatographic method used a monolithic C18 column and both diode array and fluorescence detection. This procedure was validated for the analysis of drugs in cow urine, using a simple and fast procedure with methanol/acetonitrile, allowing the simultaneous and efficient extraction of most of the studied drugs.

New developments in microextraction techniques in bioanalysis. A review.

In recent years, the interest in new extraction methods with lower sample volume requirements, simpler equipment and handling, and lower reagent consumption, has led to the development of a series of microextraction methods based on extraction phases in the microliter order. Nowadays, many references can be found for several of these methods, which imply a wide range of applications referred to both the analyte and the sample nature. In this paper, recent developments in both well-established microextraction techniques (solid phase microextraction, hollow-fiber liquid phase microextraction, dispersive liquid-liquid microextraction, etc.

New developments in the extraction and determination of parabens in cosmetics and environmental samples. A review.

Parabens are a family of synthetic esters of p-hydroxibenzoic acid widely used as preservatives in cosmetics and health-care products, among other daily-use commodities. Recently, their potential endocrine disrupting effects have raised concerns about their safety and their potential effects as emerging pollutants, leading to the regulation of the presence of parabens in commercial products by national and trans-national organizations. Also, this has led to an interest in developing sensible and reliable methods for their determination in environmental samples, cosmetics and health-care products.

Agar films containing silver nanoparticles as new supports for electromembrane extraction.

A new support containing silver nanoparticles to assist electromembrane extraction (EME) procedures is proposed. For the first time, synthesized agar films containing silver nanoparticles (AgNPs) have been used as a support for liquid membranes in EME. Agarose films of 20 μm thickness containing 107.

Hollow-fiber liquid-phase microextraction for the direct determination of flumequine in urban wastewaters by flow-injection analysis with terbium-sensitized chemiluminescence.

A flow-injection analysis chemiluminescence method based on the enhancement effect of the flumequine-Tb(III) complex on the weak native emission of the Ce(IV)-Na2SO3 system has been developed for the determination of flumequine. The method includes a cleanup and preconcentration stage (750-fold) of the sample by hollow-fiber liquid-phase microextraction using an Accurel(®) Q 3/2 polypropylene hollow fiber impregnated with 1-octanol as the supported liquid membrane. The obtained 50 μL acceptor phase was injected in a 1 mM Tb(III) + 4 mM Ce(IV) in 5% v/v H2 SO4 stream and mixed with a 2 mM Na2 SO3 stream before its introduction into the flow cell.

Application of chemiluminescence in the analysis of wastewaters - a review.

The toxicological effects of diverse pollutants typically found on wastewaters of diverse origin (industrial, urban, etc.) have led to regulation of their emission by national and trans-national organizations, and an increasing interest in the development of fast and reliable methods for their analysis. This paper is an up-to-date comprehensive review on the analytical applications of chemiluminescence technique (characterized by high sensitivity, wide dynamic ranges and simple instrumentation) to the analysis of wastewaters, emphasizing the different kinds of pollutants that have been studied with these methods and discussing the different approaches followed by the authors as CL reactions, devices and coupled methods.

Hollow fiber-based liquid phase microextraction (HF-LPME) as a new approach for the HPLC determination of fluoroquinolones in biological and environmental matrices.

In this paper, a three phase hollow fiber-based liquid phase microextraction (HF-LPME) combined with a HPLC procedure using diode array (DAD) and fluorescence detection (FLD) has been developed for the determination of eight widely used fluoroquinolones: marbofloxacin (MRB), norfloxacin (NRF), ciprofloxacin (CPR), danofloxacin (DNF), enrofloxacin (ENR), gatifloxacin (GTF), grepafloxacin (GRP) and flumequine (FLM). A Q3/2 Accurel PP polypropylene hollow fiber supporting 1-octanol was used between a 2 M Na2SO4 aqueous solution (pH 7) as donor phase and aqueous solution (pH 12) as acceptor phase. The microextraction parameters were optimised from an experimental central composite design.