Immunochemical detection of apramycin as a contaminant in tissues of edible animals

- Conjugate of periodate-oxidized fetuin with AP was used for immunization rabbits.
- High sensitive and selective indirect competitive ELISA was developed using prepared antibodies.
- Detection limit IC90 and dynamic range of assay IC20-IC80 were 0.075 and 0.15-9 μg/kg.
- Matrix effect of tissue samples was studied and eliminated by simple extract dilution.
- Recovery of AP in kidney and muscle samples at ½, 1 and 2 MRL was ranged 85-105%.

Veterinary aminoglycoside antibiotic apramycin (AP) was used as hapten in different conjugation procedures for preparation of immunogen and coating antigens. Among the coating antigens one was chosen to ensure strictly selective determination of AP with no cross-reactivity of related analogs. The limit of competitive ELISA detection was 0.015 ng/ml for swine kidney and bovine muscle extracts. The dynamic range IC20-IC80 was calculated as 0.03-1.8 ng/ml (0.15-9 μg/kg). High sensitivity of assay allowed eliminating matrix effect of samples by simple dilution of tissue extracts. The experiments with tissue samples fortified with AP at half, single and double MRL values showed the recovery rate of 85-105%. Along with the other immunotests and kits for determination of aminoglycosides this for the first time developed assay of apramycin is suitable for screening of antibiotic residues in foodstuff.