Biocompatible conductive architecture with surface-confined probe for non-invasive electrochemical cytosensing

The possibility of using electrochemical methods to investigate cell immobilization and natural physiological states provides great advances in life science research and public health protection. Herein, cytosensors with surface-confined ferrocene as signal indicator were developed to study the immobilization of human cervical carcinoma (HeLa) cells. With layer-by-layer (LBL) technique positively charged ferrocene functionalized poly(allylamine hydrochloride) (Fc-PAH) and negatively charged single-wall carbon nanotubes (SWNTs) were alternately assembled on 3-mercaptopropionic acid (MPA) modified gold substrates. The as-prepared cytosensors presented good biocompatibility and HeLa cells could keep viability for 72 h on the materials according to the proliferation results. With differential pulse voltammetry (DPV) measurements the cytosensors exhibited high sensitivity to the detection of HeLa cells within a wide concentration range from 10 to 107 cells/mL.

► A cell-based biosensor with high sensitive was prepared. ► Surface-confined ferrocene was used as signal indicator. ► The biosensor can avoid the effect of external redox probe on the cells. ► Long time of electric field effect on the cells was avoided with DPV measurement. ► The detection concentration range of HeLa cell was from 10 to 107 cells/mL.