Quartz crystal microbalance with dissipation as a biosensing platform to evaluate cell-surface interactions of osteoblast cells

Quartz crystal microbalance with dissipation (QCM-D) is one of the powerful techniques, which allow real time, quantitative and noninvasive analysis of the interaction of different cell types with various modified surfaces. In this study, the dynamic adhesion behavior of human fetal osteoblastic bone (hfOB) cell lines was first monitored on untreated and hydrophilically treated gold sensor surfaces as reference substrates. Adhesion was also observed under light microscopy to facilitate the evaluation. Cells increased their surface contact area and spread more on hydrophilic surfaces, and showed distinct profile with an increased rigidity at the interfacial layer, which is assigned to extracellular matrix remodeling. Further, the adhesion strength and kinetics were characterized on cell adhesive (poly-l-lysine and fibronectin) and repellent (bovine serum albumin) surfaces. The overall results indicated that protein-mediated specific interactions contributed mostly to the dissipation changes (ΔD) or acoustic ratio (ΔD/Δf). Finally, the potential of QCM-D to distinguish healthy and cancerous cells were evaluated by comparing the results of hfOB cells with that of SaOS-2 (osteosarcoma) cancerous cells. Cancerous cells interacted more strongly and showed more viscoelastic characteristic than the healthy cells.