Determination of streptomycin residues in animal-derived foods by a reliable and accurate enzyme-linked immunosorbent assay

Abstract

A highly reliable and accurate indirect competitive enzyme-linked immunosorbent assay (icELISA) was developed for the detection of streptomycin (STR) in animal-derived foods. The half-maximum inhibition concentration (IC₅₀) of the icELISA for STR was 2.00 ng mL⁻¹ and the limit of detection (LOD, calculated as the IC₁₅ value) was 0.24 ng mL⁻¹. The cross-reactivities with other aminoglycoside antibiotics were very low except for dihydrostreptomycin (95.50%). The recoveries for all samples at five levels (15, 30, 120, 300, 600 ng g⁻¹) ranged from 71.32% to 106.94%. The coefficients of variation of intra- and inter-assays were below 14%. There was a good correlation (R² = 0.9854) between the data determined by this ELISA and the commercial kit. The analysis of variance of the recoveries showed the sufficiently high stability of the assay to STR in eight animal-derived foods (chicken, pork, chicken liver, pig liver, pig kidney, fish, shrimp, and cow milk). The ELISA allows for a rapid, low-cost, sensitive and accurate determination of STR residues in animal-derived foods.