A regenerable immunochip for the rapid determination of 13 different antibiotics in raw milk

Access to high-quality and safe food is a basic need in our community and, consequently, the European Union has defined maximum residue levels (MRLs) for a number of antibacterial compounds. However, despite the obvious demand for quantitative multi-residue detection methods that can be carried out on a routine basis, there is currently a lack in the development of such systems. In particular, an automated multianalyte detection instrument is needed that is capable of quantifying several antibiotics simultaneously within minutes. The newly developed hapten microarrays are designed for the parallel analysis of 13 different antibiotics in milk within six minutes by applying an indirect competitive chemiluminescence microarray immunoassay (CL-MIA). To allow multiple analyses, a regenerable microarray chip was developed based on epoxy-activated PEG chip surfaces, onto which microspotted antibiotic derivatives like sulfonamides, beta-lactams, aminoglycosides, fluorquinolones and polyketides are coupled directly without further use of linking agents. Using the chip reader platform MCR 3, this antigen solid phase is stable for at least 50 consecutive analyses.