Immunochemical detection of aminoglycosides in milk and kidney

In 1996, the European Union established provisional maximum residue limits (MRL) for gentamicin, neomycin, streptomycin and dihydrostreptomycin in mil k and tissue (0.1-5 mg kg(-1)). For the detection of these four aminoglycos ides, three enzyme linked immunosorbent assays (ELISA) for applications in milk and kidney were developed. The screening of defatted and diluted milk resulted in limits of determination (LDM) of < 0.01 mg l(-1). Kidney sample s were deproteinized with a trichloroacetic acid solution (3%) and after fi ltration and the addition of buffer, aliquots were used in the ELISA. The L DM of the four aminoglycosides in kidney were < 0.05 mg kg(-1). The ELISA w ere found suitable for the semi-quantitative screening of milk and kidney f or the presence of the four aminoglycosides far below the MRL levels. In ra ndomly taken milk samples (n = 776) and in kidneys derived from healthy pig s (n = 124), the aminoglycoside residues found were far below their establi shed MRL. In eight out of the 93 kidney samples obtained from diseased anim als after emergency slaughter, aminoglycoside residues were above the MRL.