An on-line quantitative immunoassay system based on a quartz crystal microbalance.

We have established a QCM immunoassay system which allows on-line and quantitative monitoring throughout the entire detection procedure and provides information on the surface coverage and the binding ratio of antibody to antigen. Compared to conventional immunoassay systems the QCM system offers advantages of short response times, obviates the need for additive labeling reagents, and permits direct conversion of a frequency signal into mass accumulation.