Measurement of β-agonist residues in retinal tissue of food producing animals

Abstract

This report presents the results of an investigation on the accumulation of beta-agonist residues in the retinal tissue of food producing animals. Three different species, calf, pig and turkey, were treated with six different beta-agonists and analysed for beta-agonist residues in retinal tissue applying a newly developed retina preparation procedure which provides sufficient sample material for multiple analyses. The results show that all selected beta-agonists accumulate in the retina, though in varying concentrations. The results are discussed on the basis of existing binding theories and with regard to their impact on the existing residue control strategy for beta-agonists.

Electrostacking online sample pre‐concentration capillary electrophoresis with amperometric detection for β2‐agonists in human urine

“…The great majority of techniques applied to determine b 2 -agonists are based on GC-MS [4], LC-MS [5] and HPLC [6]. However, a derivatization step is required prior to GC-MS analysis, which is complicated and timeconsuming.…”

Das Europäische Netzwerk für die Rückstandskontrolle

“…(Polzer et al, 2004). Außerdem ist eine ununterbrochene Tiefkühlkette für die Probenahme erforderlich, da die Substanzen teilweise sehr schnell zersetzt werden zum Akkumulations-Verhalten von Beta-Agonisten in Retina (Gowik et al, 2000) sowie von dem in Drittländern teilweise zugelassenem Wachstumsförderer Zilpaterol (Stachel et al, 2003) durchgeführt. Mit diesem komplexen Thema beschäftigt sich das Referenzlabor seit Jahren intensiv, um den Routinelaboratorien Empfehlungen zum korrekten Vorgehen bei der Ermittlung der Gesamtmessunsicherheit einer analytischen Methode geben zu können.…”

Method development and validation for zotarolimus concentration determination in stented swine arteries by liquid chromatography/tandem mass spectrometry detection

“…Alternatively, liquid chromatography/tandem mass spectrometry (LC/MS/MS) has been widely used for the determination of drug concentrations in fluid format biological matrices such as blood, plasma and urine 4, 5. In addition, there is an increasing number of publications on the use of LC/MS/MS to monitor tissue drug concentrations in drug food residues and in drug discovery 6–25. Tissue samples are generally converted into the liquid format and subsequently, similar to other biological fluid samples, liquid format samples go through further cleanup prior to LC/MS/MS analysis.…”

“…Tissue samples are generally converted into the liquid format and subsequently, similar to other biological fluid samples, liquid format samples go through further cleanup prior to LC/MS/MS analysis. Although sample processing such as hydrolysis6–8 or enzymatic digestion9 has been used for converting solid tissue sample into liquid format, tissue homogenization10–25 is most widely used. The use of an automated multichannel homogenizer (autogizer) also significantly reduces the labor intensity and improves the throughput and consistency of tissue homogenization.…”