A new issue of this journal has just been published. To see abstracts of the papers it contains (with links through to the full papers) click here:
Selected papers from the latest issue:
Determination of quinolones of veterinary use in bee products by ultra-high performance liquid chromatography–tandem mass spectrometry using a QuEChERS extraction procedure
29 February 2012, 00:44:26
Publication year: 2012
Source: Talanta, Available online 28 February 2012
Manuel Lombardo-Agüí, Ana M. García-Campaña, Laura Gámiz-Gracia, Carmen Cruces-Blanco
A reliable and rapid Ultra High Performance Liquid Chromatography tandem Mass Spectrometry (UHPLC-MS/MS) method has been developed for the determination of the eight quinolones of veterinary use regulated by European Union (marbofloxacin, ciprofloxacin, danofloxacin, enrofloxacin, sarafloxacin, difloxacin, flumequine and oxolinic acid). Chromatographic conditions were optimised in order to increase sample throughput and sensitivity. The antibiotics were detected by electrospray ionization in positive ion mode with multiple reaction monitoring (MRM) and MS/MS conditions were optimized in order to increase selectivity, selecting the corresponding product ions for quantification and identification. The separation was achieved in 3 min, using a Zorbax Eclipse Plus C18 column (50 × 2.1 mm, 1.8 μm), with a mobile phase of 0.02% aqueous formic acid solution and acetonitrile. A dispersive solid phase extraction methodology, often referred to as the “QuEChERS” (Quick, Easy, Cheap, Effective, Rugged, and Safe) method, was optimized for extraction of the quinolones from honey and also it was evaluated for other bee products such as royal jelly and propolis. The method was validated for each matrix in terms of linearity, trueness, precision, limits of detection (LODs) and quantification (LOQ). LODs ranged between 0.2 and 4.1 μg kgwith precision lower than 12% and satisfactory recoveries in most cases. The method was also applied for studying the occurrence of these antibiotics in several market samples.
Source: Talanta, Available online 28 February 2012
Manuel Lombardo-Agüí, Ana M. García-Campaña, Laura Gámiz-Gracia, Carmen Cruces-Blanco
A reliable and rapid Ultra High Performance Liquid Chromatography tandem Mass Spectrometry (UHPLC-MS/MS) method has been developed for the determination of the eight quinolones of veterinary use regulated by European Union (marbofloxacin, ciprofloxacin, danofloxacin, enrofloxacin, sarafloxacin, difloxacin, flumequine and oxolinic acid). Chromatographic conditions were optimised in order to increase sample throughput and sensitivity. The antibiotics were detected by electrospray ionization in positive ion mode with multiple reaction monitoring (MRM) and MS/MS conditions were optimized in order to increase selectivity, selecting the corresponding product ions for quantification and identification. The separation was achieved in 3 min, using a Zorbax Eclipse Plus C18 column (50 × 2.1 mm, 1.8 μm), with a mobile phase of 0.02% aqueous formic acid solution and acetonitrile. A dispersive solid phase extraction methodology, often referred to as the “QuEChERS” (Quick, Easy, Cheap, Effective, Rugged, and Safe) method, was optimized for extraction of the quinolones from honey and also it was evaluated for other bee products such as royal jelly and propolis. The method was validated for each matrix in terms of linearity, trueness, precision, limits of detection (LODs) and quantification (LOQ). LODs ranged between 0.2 and 4.1 μg kgwith precision lower than 12% and satisfactory recoveries in most cases. The method was also applied for studying the occurrence of these antibiotics in several market samples.
Highlights
► Eight quinolones in bee products by UHPLC-MS/MS analysis ► Development of QuEChERS as cheap and efficient method for extraction and clean up ► Validation of the method in three different products (honey, royal jelly and propolis) ► LODs between 0.2 and 4.1 μg kgwith precision lower than 12%•Developed method applied to different types of bee product samplesPotentiometric Determination of Tolterodine in Batch and Flow Injection Analysis
29 February 2012, 00:44:26
Publication year: 2012
Source: Talanta, Available online 28 February 2012
Marwa M. Sakr, Rasha M. El Nashar
Two new ion-selective electrodes of the plastic membrane type for the determination of Tolterodine (Tol) were prepared. These electrodes depend on the incorporation of the ion- exchangers of the above mentioned drug with phosphotungestic acid (PTA) or Silicotungestic acid (STA) in a PVC matrix. A comparative study is made between the performance characteristics of electrodes containing ion-exchanger in batch and FIA conditions.The usable concentration range of the electrodes was found to be (1.0 × 10–1.0 × 10and 5.0 × 10–1.0 × 10 M) in batch and FIA conditions, respectively. The electrodes have nearly the same usable concentration, pH range and exhibited high selectivity towards Tol in the presence of many inorganic cations and can be used in biological fluids such as urine and plasma. The dissolution profile of the investigated drug as well as its assay in pure and pharmaceutical preparations was performed, and the results were relatively accurate and precise as indicated by the recovery values and coefficients of variation.
Source: Talanta, Available online 28 February 2012
Marwa M. Sakr, Rasha M. El Nashar
Two new ion-selective electrodes of the plastic membrane type for the determination of Tolterodine (Tol) were prepared. These electrodes depend on the incorporation of the ion- exchangers of the above mentioned drug with phosphotungestic acid (PTA) or Silicotungestic acid (STA) in a PVC matrix. A comparative study is made between the performance characteristics of electrodes containing ion-exchanger in batch and FIA conditions.The usable concentration range of the electrodes was found to be (1.0 × 10–1.0 × 10and 5.0 × 10–1.0 × 10 M) in batch and FIA conditions, respectively. The electrodes have nearly the same usable concentration, pH range and exhibited high selectivity towards Tol in the presence of many inorganic cations and can be used in biological fluids such as urine and plasma. The dissolution profile of the investigated drug as well as its assay in pure and pharmaceutical preparations was performed, and the results were relatively accurate and precise as indicated by the recovery values and coefficients of variation.
Highlights
► Tolterodine chemical sensor is characterized in batch and FIA conditions. ► LOD was 20.5 μg and 25.7 μg and LOQ of 32.5 μg for Tol-PTA and Tol-STA electrodes. ► The electrodes were used for the assay of dosage forms and biological samples. ► The electrodes were applied for dissolution profile of Detrusitolcapsules.A dual-electrode flow sensor fabricated using track-etched microporous membranes
29 February 2012, 00:44:26
Publication year: 2012
Source: Talanta, Available online 27 February 2012
Hitoshi Mizuguchi, Kanako Shibuya, Azumi Fuse, Tomoko Hamada, Masamitsu Iiyama, ...
A new dual-electrode flow sensor has been fabricated by piling the microporous membrane electrodes which have 7–10 μm thickness. The electrode was prepared by sputtering of platinum onto both sides of the membrane filter which contain a smooth flat surface as well as cylindrical pores with uniform diameters. The electrolysis is performed when the sample solution flows through the membrane electrode, and a generated analyte on the first working electrode is instantaneously transported to the surface of second working electrode which is located at the downstream of the first one. In this case, the sample solution surely flows through the pores of the membrane filters. As the result, highly efficient electrolysis was achieved at each electrode, and the collection efficiency values as high as 100% were obtained in the wide range of flow rate. Good responses to the injections of sample solutions were also confirmed in the FIA system.
Source: Talanta, Available online 27 February 2012
Hitoshi Mizuguchi, Kanako Shibuya, Azumi Fuse, Tomoko Hamada, Masamitsu Iiyama, ...
A new dual-electrode flow sensor has been fabricated by piling the microporous membrane electrodes which have 7–10 μm thickness. The electrode was prepared by sputtering of platinum onto both sides of the membrane filter which contain a smooth flat surface as well as cylindrical pores with uniform diameters. The electrolysis is performed when the sample solution flows through the membrane electrode, and a generated analyte on the first working electrode is instantaneously transported to the surface of second working electrode which is located at the downstream of the first one. In this case, the sample solution surely flows through the pores of the membrane filters. As the result, highly efficient electrolysis was achieved at each electrode, and the collection efficiency values as high as 100% were obtained in the wide range of flow rate. Good responses to the injections of sample solutions were also confirmed in the FIA system.
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