ABSTRACT
A simple and rapid method, using supercritical fluid extraction (SFE) with off-line high-performance liquid chromatography for the isolation and determination of nicarbazin, a popular broad-spectrum coccidiostatic drug used principally in poultry, is described. Results show good repeatability with a minimum quantification level of 0.4 microgram g-1 and mean 'spiked' recoveries of 98%, 100% and 99% using poultry feeds (n = 18), eggs (n = 28) and chicken tissue (n = 20), respectively. SFE using carbon dioxide is proposed as an alternative isolation method to the current Association of Official Analytical Chemists (AOAC) procedure which involves the use of large volumes of a harmful solvent (dimethylformamide) and requires a long tedious separation and clean-up regime (6 h) prior to its determination.
Subject(s)
Coccidiostats/analysis , Drug Residues/analysis , Eggs/analysis , Meat/analysis , Nicarbazin/analysis , Animal Feed/analysis , Animals , Chickens , Chromatography, High Pressure Liquid/methods , Food ContaminationABSTRACT
The stability of several medicinal additives in cattle, pig and poultry feeds has been monitored. The feeds were stored at various temperatures under different conditions; processes such as freeze-drying, gamma-irradiation and pelletization were also applied. The medicinal additives appeared to be more stable in the feeds stored at reduced temperatures and under conditions that totally exclude light. Processing of feeds and storage at elevated temperature appeared to reduce the content of the medicinal additives examined.
Subject(s)
Animal Feed/analysis , Drug Residues/analysis , Food Additives/analysis , Animal Feed/radiation effects , Chromatography, Ion Exchange , Drug Residues/radiation effects , Food Additives/radiation effects , Freeze Drying , Gamma RaysABSTRACT
Traditionally, bioassay has been the chosen technique for the determination of bacitracin compounds in animal feedingstuffs. However, detection and determination of this antibiotic have given problems when it is present at low levels. A competitive enzyme-linked immunosorbent assay (ELISA) by which it is possible to detect both bacitracin and zinc bacitracin at levels as low as 1 mg kg-1 in animal feeds is described. The ELISA technique has been used in this laboratory to monitor samples from a drug stability storage trial for the presence of zinc bacitracin. In addition, individual polypeptide components of zinc bacitracin have been separated by high-performance liquid chromatography. Fractions were collected and tested by the ELISA technique to assess the response between individual components and the primary antibody. The response was compared with known microbiological activity.
Subject(s)
Animal Feed/analysis , Bacitracin/analysis , Bacitracin/immunology , Chromatography, High Pressure Liquid , Enzyme-Linked Immunosorbent AssayABSTRACT
A method is described for the detection of 25 drugs used as prophylactics or as growth promoters in commercial animal feedingstuffs. The sample was extracted with aqueous acetonitrile, the co-extractives were removed with a silica cartridge and the eluate was examined by high-performance liquid chromatography, using two columns and five mobile phases. Thirteen animal ++feedingstuffs containing different combinations of drugs were prepared and used to test the method.
Subject(s)
Animal Feed/analysis , Pharmaceutical Preparations/analysis , Chromatography, High Pressure LiquidABSTRACT
Chemical methods of analysis for the extraction, clean-up and determination of aflatoxins from animal feedingstuffs and foods are described. The advantages and disadvantages of thin layer chromatography (t.l.c.) and high pressure liquid chromatography (h.p.l.c.) are discussed along with newer techniques such as immunoassay. Methods for other mycotoxins such as ochratoxin, patulin, and the trichothecenes are also included. Problems encountered during collaborative testing of these methods limit the reproducibility that can be achieved.
