Real-time monitoring of the cell agglutination process with a quartz crystal microbalance

The real-time monitoring of the agglutination process of human hepatic normal cells (L-02) at the quartz crystal microbalance (QCM) gold (An) electrode was performed. Two lectins, concanavalin A (Con A) and wheat germ agglutinin (WGA), induced the cell agglutination, resulting in the different Delta f(0) and Delta R-1 responses from those caused by the normal cell attachment and growth. The cell-Con A-cell aggregates had higher affinity for the Au substrate due to the excellent adsorption ability of Con A, which was revealed by increased Delta f(0) and Delta R-1, shifts and the obvious mass effect of QCM. In contrast, the lower adsorption ability of cell-WGA-cell aggregates was related to the same characteristic of WGA, presenting the decreased Delta f(0) and Delta R-1 responses and the time-extended adhesion phase. Parallel microscopic observation experiments were also carried out and exhibited comparable results. The Delta f(0) responses during the processes of cell growth and cell agglutination were analyzed using the equations Delta f(0) = a(0) + a(1)e(-t/tau 2) + a(2)e(-t/tau 3) + a(3)e(-t/tau 3) and Delta f(0) = a(0) + a(1)e(-t/tau 1) + a(2)e(-t/tau 2), respectively. Furthermore, the current work proved that the QCM measurement technique based on cell agglutination was useful for discriminating hepatic normal cells (L-02) and hepatic cancer cells (Be17402). (c) 2008 Elsevier Inc. All rights reserved.