Biomedical subjects

Marta Calull

Publications and source records attributed to Marta Calull.

4 recordsLinked to original sources

PubMed2003

Improving sensitivity by large-volume sample stacking using the electroosmotic flow pump to analyze some nonsteroidal anti-inflammatory drugs by capillary electrophoresis in water samples.

Large-volume sample stacking using the electroosmotic flow (EOF) pump (LVSEP) has been used to analyze some nonsteroidal anti-inflammatory drugs (NSAIDs) in water samples. With methanol as the run buffer solvent to suppress the EOF, sensitivity was enhanced by 80-100-fold. The sample for the analysis of real water sample was pretreated by solid-phase extraction (SPE). When the method was based on off-line SPE-LVSEP-CE, sensitivity improved by as much as 1000 times.

Anti-Inflammatory Agents, Non-Steroidal↗

PubMed2002

Determination of ciprofloxacin, enrofloxacin and flumequine in pig plasma samples by capillary isotachophoresis--capillary zone electrophoresis.

Quinolones are a group of synthetic antibiotics that are widely used in veterinary medicine. Their residues may remain in tissues, milk, etc. intended for human consumption. The European Union fixes the maximum residue limits (MRLs) of veterinary medicinal products in foodstuffs of animal origin. Analytical methods are therefore needed to determine them in biological samples. In this study, we describe capillary isotachophoresis-capillary zone electrophoresis (ITP-CZE) to analyze three quinolones, enrofloxacin (ENR), ciprofloxacin (CPR) and flumequine (FLU), in pig plasma samples. We used solid-phase extraction with Oasis HLB cartridges as a sample pretreatment clean-up step. Capillary zone electrophoresis (CZE) requires low amounts of sample and is not as sensitive as one would wish. ITP-CZE is an easy way to increase the sample loadability and sensitivity. With this system sensitivity increases 40-fold. The detection limits for CPR, ENR and FLU were 70, 85 and 50 microg l(-1), respectively, which were lower than their MRLs in different kinds of samples. This method is simple and sensitive, and is therefore an alternative tool to the existing HPLC methods for analyzing the residuals of these quinolones in biological samples.

Animals↗

PubMed2002

Using nonaqueous capillary electrophoresis to analyze several quinolones in pig kidney samples.

We show the potential of nonaqueous capillary electrophoresis (NACE) for analyzing enrofloxacin (ENR), ciprofloxacin (CPR), danofloxacin (DAN), difloxacin (DIF), marbofloxacin (MAR), flumequine (FLU), and oxolinic acid (OXA) in pig kidney samples. We have studied the effects of parameters such as the composition of the organic media, the choice of electrolyte, the pH* of the background electrolyte (BGE), the addition of modifiers, and the reversal of electroosmotic flow. Separation was good with 20 mM ammonium acetate, 0.004% polycation hexadimethrine bromide (HDB), and 4% acetic acid (pH* 5.4) in methanol/acetonitrile (50:50 v/v) medium. We used a quick and simple sample preparation method, hydrochloric acid as an extractant and solid-phase extraction (SPE) with Baker C18 cartridges as the cleanup step. Recoveries for all quinolones were over 80%.

Animals↗

PubMed2002

Isotachophoretic focusing and mass spectrometry detection as tools for improving the determination of aromatic sulfonates in capillary electrophoresis.

We explored isotachophoresis-capillary zone electrophoresis (ITP-CZE) with diode array detection on a single capillary to find out how to increase the injection volume and decrease the detection limits of aromatic sulfonates in CZE. The ITP was performed by applying a negative voltage in conjunction with hydrodynamic backpressure programming, and the terminating buffer was removed before the CZE separation, which resulted in highly sensitive determinations. The ITP increased the signal response of conventional hydrodynamic injection by a factor of 100, whereas the separation efficiency was unaffected. The limits of detection of the method were between 3 and 5 nugL(-1). The method was successfully used to determine these compounds in water samples. Experimental conditions for capillary electrophoresis-mass spectrometry were optimized and applied to determine aromatic sulfonates in water samples. These techniques enables the 2-naphthalenesulfonate to be determined in water samples.

Arylsulfonates↗