Tetracycline sensing using novel doxycycline derivatives immobilized on different surface plasmon resonance biosensor surfaces.

BACKGROUND: This article aims to explore novel doxycycline derivatives for analyzing low concentrations of tetracyclines in biological matrices and food in competitive assays. RESULTS: Surface plasmon resonance (SPR) was employed in an indirect competitive format using a bacterial tetracycline-dependent regulatory protein as receptor. Three doxycycline derivatives were synthesized and covalently bound to the surface of four different sensor chips. Parameters that influence the immobilization of the doxycycline derivatives and subsequent binding of the receptor protein were studied. CONCLUSION: The novel doxycycline derivatives were successfully used as competitors in an indirect SPR assay.