Quartz crystal microbalance (QCM) as a device for the screening of phage libraries

An immunosensing system based on a quartz crystal microbalance (QCM) is pre sented for the selection of both antigen specific recombinant antibodies an d antigen specific human pancreatic secretory trypsin inhibitor (hPSTI) mut ants isolated from large phage libraries. The QCM was integrated into a flo w injection analysis system for the straightforward analysis of large sampl e numbers. Measurements were performed using a biotinylated antigen immobil ized by streptavidin onto the gold surface of the quartz crystal and phages displaying recombinant antibodies or hPSTI mutants. The results obtained b y the QCM were in accordance to those of a well established enzyme linked i mmunosorbent assay (ELISA). Therefore, the QCM is well suited for the detec tion of single high affinity clones isolated from large phage display libra ries. (C) 1999 Elsevier Science S.A. All rights reserved.