Development of an ITO-based biochip for osteoblastic attachment detection

Objectives: Bone remodeling is an important issue for the treatment of periodontal disease and dental implantation. The aim of this study is to develop a novel method to detect the viability of osteoblastic cells using cell-impedance sensing technique. Methods: An ITO-based bio-chips was developed using semiconductor technique. The AC impedance changes of the MG-63 osteoblast-like cells at various cultured density were detected. The detection was real time, automatic, continuous and, most importantly, chemical-free. To test our device for osteogenetic protein detection, the differences in electric resistance were recorded when the cells were immunostained with anti-Integrin â1 antibody coagulated with nano-scale gold particles. The efficiency of our bio-chip was evaluated by comparing the measured resistance changes to the traditional biochemical methods. Results: The cultures demonstrated a higher electric resistance when the cell demonstrated a more attached morphology. It significantly raised from 0 to about 120 Ù after 4-hr attachment and significantly increased to 246±29 Ù at day 7. In addition, cells express more Integrin â1 on cell surface result in a lower reading of measured cell-impedance. A high correlation was found between cell impedance and immuno-fluorescence intensity (R=0.9580, p<0.005). Conclusions: The results obtained in this study provide a nondestructive means for monitoring cell morphology and the expression of Integrin protein. It can be a useful tool for the study of osteointegration.