Direct Conjugation of Penicillins and Cephalosporins with Proteins for Receptor Assays of Beta-Lactam Antibiotics

Abstract— Fifteen protein conjugates of penicillins and cephalosporins containing amino- and/or carboxylic groups in the initial structures have been synthesized reactions with human serum albumin or ovalbumin using 1-ethyl-3-[3-dimethylaminopropyl]carbodiimide hydrochloride (EDC) a combination EDC N -hydroxysulfosuccinimide at various ratios base reagents. A comparative study composition properties has carried out by UV spectroscopy, mass spectrometry ligand-receptor assay. It was shown that antibiotic residue content macromolecules obtained varied from 1 to 22, beta-lactam cycle remained intact assuring specific interactions penicillin-binding protein. In two developed models receptor bioanalytic systems, an ampicillin conjugate onto solid phase binds complexed monoclonal antibody, which detected immunoenzyme label microplate wells gold nanoparticles on test strips. Conjugated binding competitively inhibited antibiotics added liquid phase, analytical sensitivities relative penicillin G were 0.05 ng/mL for chromatographic respectively.