Sulfur based self-assembled monolayers (SAM's) on piezoelectric crystals for immunosensor development

Self-assembled monolayers (SAM's) of different thiols and sulfides with var ious structures were tested. They were investigated as a method to covalent ly bind antibodies to the surface of piezoelectric crystals. A capture assa y using a Mouse IgG test system was performed. All tests were performed in solution. The reduction in frequency observed as binding occurred was monit ored in real time. The SAM's were activated with 1-ethyl-3-[3-(dimethylamin o)propyl] carbodiimide hydrochloride (EDC) and N-hydroxysulfosuccinimide (N HS) prior to antibody immobilisation. Ethanolamine was used to block any av ailable activated sizes after antibody immobilisation. The potential of thi s technique for immunosensor development is demonstrated.