Determination of quinolones in chicken tissues by liquid chromatography with ultraviolet absorbance detection.
ABSTRACT This paper presents an analytical method for the determination of quinolones in chicken tissues. The procedure involves pre-treatment by solid-phase extraction (SPE) and subsequent liquid chromatography (LC) with UV absorbance detection. Different SPE disposable cartridges and extractants of the tissue samples were tested, and various columns were systematically tested. The mobile phase was composed of acetonitrile and citric buffer at pH 4.5, with an initial composition of acetonitrile-water (12:88, v/v) and using linear gradient elution. Recoveries were 66-91% in the concentration range 30-300 microg kg(-1). The detector response was linear in this range. The limits of detection were 16-30 microg kg(-1). These values were lower than the maximum residue limits established by the European Union.
- SourceAvailable from: Nadezhda A. Stoilova[Show abstract] [Hide abstract]
ABSTRACT: The objective of this study was to present simple, rapid and applicable HPLC-method with fluorescence detection for determination of quinolone-residues in chicken muscle. Presence of antibacterial residia gives reise to risk for health, because of chance by disease, allergy or cancer effect. The residues of ciprofloxacine, enrofloxacine, norfloxacine, danfloxacine, difloxacine, sarafloxacine, oxolinic acid, nalidixic acid and flumequine are extracted with acetonitril. The extract was cleaned with an SPE -procedure with HLB cartridges. Elute was analyzed via Zorbax Eclipse XDB liquid chromatography column. It was used gradient program for eluting and time table program because of the different wave lengths of excitation and emission. INTRODUCTION The quinolones are a group of antibiotics which are used in human and veterinary medicine. They have high activity against gram-positive and gram-negative bacteria. Their activity is shown by inhibiting of DNA-guirase in a bacterial cell , thus destroying it. The use of quinolone-antibiotics has resulted in the presence in food with animal origin. The European Union has established maximum residue limits for those types of chemicals in different type of animal tissues and food with animal origin. The aim is to protect the human health against potential harmful residues [2, 3]. That make necessary to develop and validate sensitive and selective multi-residue screening method for identification and quantification of those type antibiotics.Trakia Journal of Sciences. 01/2010; 8(1):64-69.
- [Show abstract] [Hide abstract]
ABSTRACT: 17β-Estradiol (E2) surface molecularly imprinted polymers have been prepared using functionalized monodispersed poly(glycidyl methacrylate-co-ethylene dimethacrylate) beads as a support. The resulting polymers were found to be uniform in size (5 μm), and the surfaces of the microspheres possessed large pore-like structures. A chromatographic experiment demonstrated that the resulting microspheres exhibited high levels of recognition and selectivity toward the target molecule. The particles were employed as a novel sorbent in a molecularly imprinted SPE protocol. A method was then developed involving the combination of the pretreatment with HPLC to determine the levels of estrogen secreted from Michigan Cancer Foundation-7 cells. The obtained results revealed that the extraction recoveries of E2 from real samples were in the range of 73.0-97.5% with RSDs of < 7.5% (n = 3). Calibration curves were established with R values > 0.9996 for concentrations in the range of 0.50-100.00 ng/mL. The LOD of this new method was 0.14 ng/mL. Compared with traditional C18 SPE agents, the particles showed high selectivity and extraction efficiency for E2 in the pretreatment process. The particles could therefore be used to determine trace estrogen in biological samples with a UV detector only.Journal of Separation Science 09/2013; · 2.59 Impact Factor
- [Show abstract] [Hide abstract]
ABSTRACT: A confirmatory analytical method for simultaneous determination of nine regulated quinolones (Council Regulation 2377/90/ECC) in six matrices of animal origin is proposed. The sample pretreatment involves double step liquid extraction with acetonitrile and purification by solid-phase extraction on Oasis HLB cartridges. The quinolones were separated by liquid chromatography on C18 Zorbax column with gradient elution program. Aqueous formic acid, methanol, and acetonitrile were used as a mobile phase. A multi-wavelength excitation/emission program was used for sensitive fluorescence detection of quinolones. The proposed sample pretreatment protocol was applied to each of the six studied matrices without any modification. The method was validated according to Commission Decision 2002/657 EC. Residues were quantified down to 15 μg kg−1 with limits of detection and quantification ranging from 3 to 50 μg kg−1 and from 7.5 to 100 μg kg−1, respectively. The recoveries at the maximum residual limits (MRLs) were between 77 and 120 % with RSD values lower than 30 %. For quinolones without established MRL or maximum required performance limit, the accuracy and precision of the method were estimated at concentration levels corresponding to the lowest linear calibration point and recoveries between 70 and 130 % were achieved. Decision limits, detection capability, and linear range in eggs, milk, fish, ovine muscle, chicken muscle, and porcine kidney are also reported.Food Analytical Methods 6(3). · 1.80 Impact Factor