Regeneration of immobilized antibodies on fiber optic probes

The regeneration of antibodies covalently immobilized to an optical fibre surface was investigated by dissociation of the antibody-antigen complex with three different solvents: (a) an acidic solution (0.1 M glycine hydrochloride in 50% (v/v) ethylene glycol, pH 1.75), (b) a basic solution (0.05 M tetraethylamine in 50% (v/v) ethylene glycol, pH 11.0) and (c) 50% (v/v) ethanol in PBS. The fibres coated with polyclonal rabbit anti-goat antibody against a large protein retained 70% and 65% of the original signal after five consecutive regenerations with acidic and basic solvent systems, respectively. The fibres coated with monoclonal mouse anti-trinitrobenzene antibody specific for a small organic molecule, retained over 90% of the original signal when regenerated with basic and ethanol solutions. This study evaluated regeneration and reuse of antibody-coated fibre optic biosensors as a means of reducing routine laboratory analysis costs and time.