BIOLOGICALLY DERIVED NANOPARTICLE ARRAYS VIA A SITE-SPECIFIC RECONSTITUTION OF FERRITIN AND THEIR ELECTROCHEMISTRY

ABSRACT Nanoparticle arrays biologically derived from an electrochemically- controlled site-specific biomineralization were fabricated on a gold sub- strate through the immobilization process of biomolecules. The work re- ported herein includes the immobilization of ferritin with various surface modifications, the electrochemical biomineralization of ferritins with dif- ferent inorganic cores, the fabrication of self-assembled arrays with the immobilized ferritin, and the electrochemical characterization of various core materials. Protein immobilization on the substrate is achieved by an- choring ferritins with dithiobis-N-succinimidyl propionate (DTSP). A re- constitution process of electrochemical site-specific biomineralization with a protein cage loads ferritins with different core materials such as Pt, Co, Mn, and Ni. The ferritin acts as a nano-scale template, a biocompati- ble cage, and a separator between the nanoparticles. The nano-sized metal- cored ferritins on a gold substrate displayed a good electrochemical activ- ity for the electron transport and storage, which is suitable for bioelectron- ics applications such as biofuel cell, bionanobattery, biosensors, etc.