The present invention provides a novel device for biosensing and energy storage. The present invented device comprises an electrode having a nanopore structured and bio-communicationally active cyclodextrin attached thereto. The device has demonstrated robust analytical performances for direct single subtype breast cancer measurements without mediators, or native enzyme, and without antibodies labeling; the device is capable to store energy by direct bio-communication with the living cancer cells at real time is demonstrated. It is beneficial in the health care diagnostic applications.