A biocompatible carbon based electrode, and its preparation process are described. The electrode is formed by first and second biocompatible chemically oxygen terminated or H-terminated carbon-based materials. The first material is configured to promote the growth or at least the direct interfacing of adult neurons on the first material without substantially promoting the growth and direct interfacing of glial cells on the first material. The second material presents a peptide coating to promote the growth and at least the direct interfacing of adult glial cells.