Biocompatible conductive architecture of carbon nanofiber-doped chitosan prepared with controllable electrodeposition for cytosensing

A novel architecture was designed by combining the biocompatibility of chitosan (CS) and excellent conductivity of carbon nanofiber (CNF). The controllable electrodeposition of soluble CNF-doped CS colloidal solution formed a robust CNF-CS nanocomposite film with good biocompatibility for the immobilization and cytosensing of K562 cells on an electrode. The formed architecture was characterized using scanning electron microscopic, infrared spectrum, contact angle, and thermogravimetric analyses. The adhesion of K562 cells on the nanocomposite film-modified electrode could be followed with electrochemical impedance spectroscopy and cyclic voltammetry. The presence of CNF facilitated the electrochemical behavior of K562 cells. The impedance of electronic transduction was related to the amount of the adhered cells, producing a highly sensitive impedance sensor for K562 cells ranging from 5 x 10(3) to 5.0 x 10(7) cells mL(-1) with a limit of detection of 1 x 10(3) cells mL(-1). This work suggested a strategy to prepare a biocompatible and conductive interface for immobilization and electrochemical detection of cells and opened a way for the application of CNF in cytosensing.