Human cytomegalovirus detection by a quartz crystal microbalance immunosensor

A piezoelectric affinity sensor has been developed to detect distinctive an tigens of the human cytomegalovirus. Either the specific antibodies or the antigen were immobilized on the gold electrode. To develop a rapid immunoas say, various assay formats were tested in relation with the different antig en composition. First, a direct assay was carried out immobilizing the spec ific antibody on the crystal surface by passive adsorption. Next, Protein A , thiol/poly L-lysine mixed self-assembled monolayers were tested as method s of gold modification. A competitive format was exploited by immobilizatio n of the antigen onto the crystal activated by SAM and poly L-lysine. This procedure yielded a preliminary calibration curve. A linear range between 2 .5 and 5 mug/ml of gB epitope in solution and a detection limit of 1 mug/ml were measured. (C) 2000 Elsevier Science Inc. All rights reserved.