92D-19 |
The detection of sulfonamides in pork using SPR biosensor technology |
T. MCGRATH, S. A. Haughey, and A. Baxter. Xenosense Ltd., QUBIS, Lanyon North, Queen's University, Belfast, BT7 1NN, United Kingdom In modern farming, sulfonamides are regularly incorporated in pig feed for prophylactic use and for the treatment of disease. Withdrawal periods from this medication must be adhered to before treated animals can be sent for slaughter. Consumers are concerned about the non-adherence to these withdrawal periods and possible feed contamination, factors which may lead to residues of these drugs remaining in meat following slaughter. Potential risks to the consumer include allergic reaction, but the main concern is that repeated low-dose exposure encourages the development of sulfonamide resistant bacteria. The objective of this work was to create a single immunoassay that could detect the sulfonamide group of drugs using the Biacore® Q SPR biosensor and sensor chip technology. A monoclonal antibody was obtained that displays broad-spectrum cross-reactivity for the sulfonamide group. The antibody has the added advantage of not recognising N-acetyl metabolites, the main source of interference in sulfonamide immunoassays. The biosensor method is an inhibition assay and detects the antibody when it binds to a sulfonamide derivative immobilised on the chip surface. The presence of sulfonamides inhibits this interaction. This binding event is monitored and measured using the SPR biosensor. The sensor chip surface can then be regenerated in preparation for the next sample. Sample preparation is minimal. Pork tissue samples are simply homogenised in buffer and centrifuged prior to analysis. The cross-reactivity profile and validation results for the detection of sulfonamides in pork will be presented. The significance of this work is the development of a rapid screening assay for the sulfonamide group that can be implemented in statutory testing programs worldwide.
Session 92D, Quality Assurance: General
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