Direct investigations of the electrical conductivity of normal and cancer breast cells by conductive atomic force microscopy.

Breast cancer is one of the most commonly diagnosed malignant cancers that threatens the health of women severely. The pathogenesis has not been revealed exhaustively due to the complex mechanisms. Evidences suggest that electrical conductivity properties play critical roles in cellular functions and activities. But the roles of electrical conductivity in pathogenesis of breast cancer cells have not been studied clearly at the nanometer level yet. In the present work, the electrical conductivity and electron transport of two normal and one cancer breast cell lines were investigated and compared at nanometer spatial level and picoampere current level by Conductive Atomic Force Microscopy (CAFM). The cell bodies of normal and cancer breast cells show the typical capacitor behaviors with little conductivity capability for electricity. The capacitance of cell bodies of the cancer breast cells is less than the normal breast cells. The conductivity of the processes of normal and cancer breast cells has also been investigated. The processes of the normal breast cells also exhibit the capacitor behavior. While the processes of the breast cells are electrically conductive along micrometer length scales, and show the semiconductor like conductive characteristics with Schottky barrier of 0.8391 V. All these demonstrate that the electrical conductivity of the cancer breast cells is better than the normal breast cells. This work will be helpful in the further investigations of electrical conductivity of normal and cancer cells at nanometer level, and will also pave new way in the distinguishing the cancer cells and tissues from the normal cells and tissues.