Category Archives: UV-vis

Use of onion extract as a dairy cattle feed supplement: monitoring propyl propane thiosulfonate as a marker of its effect on milk attributes.

Posted on 28 February, 2017 by fqm302

Onion extract is used as a feed supplement for the diet of dairy cows, acting as inhibitor of methane production; however, its properties could alter sensory attributes of milk. In this work, we propose a method to evaluate the influence … Continue reading →

Posted in Animal feed, HPLC, PTSO, QuEChERS, UV-vis | Tagged , , | Comments Off on Use of onion extract as a dairy cattle feed supplement: monitoring propyl propane thiosulfonate as a marker of its effect on milk attributes.

Development of magnetic molecularly imprinted polymers for selective extraction: determination of citrinin in rice samples by liquid chromatography with UV diode array detection.

Posted on 23 January, 2017 by fqm302

In this work, we report the synthesis of novel magnetic molecularly imprinted polymers (m-MIPs) and their application to the selective extraction of the mycotoxin citrinin (CIT) from food samples. The polymers were prepared by surface imprinting of Fe3O4 nanoparticles, using … Continue reading →

Posted in HPLC, MIPs, Mycotoxins, Rice, UV-vis | Comments Off on Development of magnetic molecularly imprinted polymers for selective extraction: determination of citrinin in rice samples by liquid chromatography with UV diode array detection.

Capillary electrochromatography coupled with dispersive liquid-liquid microextraction for the analysis of benzimidazole residues in water samples

Posted on 12 August, 2016 by fqm302

A novel method for the analysis of benzimidazole residues in water samples by capillary electrochromatography-UV detection (290 nm), using laboratory-made packed columns is presented. Capillaries (25 cm packed length×75 µm inner diameter, 34 cm total length, 25.5 cm effective capillary length) were packed with C18 … Continue reading →

Posted in Anthelmintic, Benzimidazoles, DLLME, Electrochromatography, P12-AGR-1647, Projects, UV-vis, Water | Tagged , | Comments Off on Capillary electrochromatography coupled with dispersive liquid-liquid microextraction for the analysis of benzimidazole residues in water samples

Evaluation of the combination of micellar electrokinetic capillary chromatography with sweeping and cation selective exhaustive injection for the determination of 5-nitroimidazoles in egg samples

Posted on 27 July, 2016 by fqm302

A methodology is presented for the sensitive determination of nitromidazole residues in egg by means of micellar electrokinetic capillary chromatography in combination with cation selective exhaustive injection and ultraviolet detection. Six compounds have been considered and the separation has been … Continue reading →

Posted in 5-nitroimidazoles, CSEI, Eggs, MEKC, P12-AGR-1647, SPE, Sweeping, UV-vis | Tagged , | Comments Off on Evaluation of the combination of micellar electrokinetic capillary chromatography with sweeping and cation selective exhaustive injection for the determination of 5-nitroimidazoles in egg samples

Trace determination of tetracyclines in water samples by capillary zone electrophoresis combining off-line and on-line sample preconcentration

Posted on 3 May, 2016 by fqm302

In this work, a sensitive and reliable method using capillary zone electrophoresis with UV detection has been developed for trace determination of tetracycline antibiotics in river, spring, and ground waters. A solid-phase extraction method using Oasis HLB was applied for … Continue reading →

Posted in CZE, LVSS, P12-AGR-1647, SPE, Tetracyclines, UV-vis, Water | Tagged , | Comments Off on Trace determination of tetracyclines in water samples by capillary zone electrophoresis combining off-line and on-line sample preconcentration

On-line preconcentration strategy for the simultaneous quantification of three local anaesthetics in human urine using capillary zone electrophoresis

Posted on 15 December, 2015 by fqm302

The simultaneous determination of usually employed anaesthetics (procaine, lidocaine and bupivacaine) has been developed and validated using capillary electrophoresis with ultraviolet detection at 212 nm. The separation of these three drugs has been achieved in less than 7 min, using … Continue reading →

Posted in Anaesthetics, CZE, FASI, UV-vis, Urine | Comments Off on On-line preconcentration strategy for the simultaneous quantification of three local anaesthetics in human urine using capillary zone electrophoresis

Hollow-fiber liquid-phase microextraction combined with capillary HPLC for the selective determination of six sulfonylurea herbicides in environmental waters

Posted on 15 October, 2013 by fqm302

A three-phase hollow-fiber liquid-phase microextraction combined with a capillary LC method using diode array detection was proposed for the determination of six sulfonylurea herbicides, triasulfuron, metsulfuron-methyl, chlorsulfuron, flazasulfuron, chlorimuron-ethyl, and primisulfuron-methyl, in environmental water samples. Different factors that can affect … Continue reading →

Posted in Capillary HPLC, Hollow-fiber liquid-phase microextraction, Sulfonylurea, UV-vis, Water | Tagged , , | Comments Off on Hollow-fiber liquid-phase microextraction combined with capillary HPLC for the selective determination of six sulfonylurea herbicides in environmental waters

Green methodology based on dispersive liquid–liquid microextraction and micellar electrokinetic chromatography for 5-nitroimidazole analysis in water samples

Posted on 19 September, 2013 by fqm302

Dispersive liquid–liquid microextraction has been proposed as an extraction technique combined with micellar  electrokinetic chromatography (MEKC) for the analysis of eight 5-nitroimidazole compounds, including some metabolites, in water samples. Determination has been carried out using a diode array detector, employing … Continue reading →

Posted in 5-nitroimidazoles, DLLME, MEKC, Sweeping, UV-vis, Water | Tagged , | Comments Off on Green methodology based on dispersive liquid–liquid microextraction and micellar electrokinetic chromatography for 5-nitroimidazole analysis in water samples

Novel solid phase extraction method for the analysis of 5-nitroimidazoles and metabolites in milk samples by capillary electrophoresis

Posted on 9 September, 2013 by fqm302

A new sample treatment has been developed for the extraction of 5-nitroimidazole (5-NDZ) drugs in milk samples previous to their determination by micellar electrokinetic chromatography (MEKC). Fat removing and protein precipitation were simultaneously carried out by the addition of trichloroacetic … Continue reading →

Posted in 5-nitroimidazoles, MEKC, Milk, SPE, Sweeping, UV-vis | Tagged , | Comments Off on Novel solid phase extraction method for the analysis of 5-nitroimidazoles and metabolites in milk samples by capillary electrophoresis

Ion-paired extraction of cephalosporins in acetone prior to their analysis by capillary liquid chromatography in environmental water and meat samples

Posted on 2 August, 2013 by fqm302

Ion-pair extraction of cephalosporins from aqueous solution into acetone by the addition of ammonium sulfate to a 1:2 (v/v) acetone–water solvent was carried out followed by their determination using reversed-phase capillary liquid chromatography. The analytes included are cephoperazone, cefquinome, cephalexin, … Continue reading →

Posted in Capillary HPLC, Cephalosporins, Meat, SALLE, UV-vis, Water | Tagged , | Comments Off on Ion-paired extraction of cephalosporins in acetone prior to their analysis by capillary liquid chromatography in environmental water and meat samples