Efficient Immobilization Methods of Antibody on Quartz Crystal Microbalance Immunosensors

We focused immobilization method of anti-C-reactive protein (CRP) monoclonal antibody on a quartz crystal microbalance (QCM) when 2-aminoethanethiol, 4,4'-dithiodibutyric acid, and 11-mercaptoundecanoic acid were respectively deposited on the gold surface of QCM. In all monolayers, anti-CRP antibody was immobilized such as Langmuir types because it had been introduced with a corresponding active group. According to the Langmuir isotherm equation, the maximum immobilized amounts of anti-CRP antibody, were 4.3, 2.7, and 3.7 pmol/cm
²
, respectively. Although the immobilized amount of anti-CRP antibody was highest on the 2-aminoethanethiol monolayer, the amount of antigen-antibody binding between anti-CRP antibody and CRP was highest on the 11-mercaptoundecanoic acid monolayer