An electrochemical probe comprises a wire bundle including two or more wire electrodes made of conducting material arranged alongside each other, and insulating material surrounding the electrodes. An impedance reducing layer of metal or metal oxide nano-structures is deposited on tips of the wire electrodes at a first end of the bundle. A functionalization layer is deposited on the impedance reducing layer at the first end of the bundle. Such a probe is particularly useful for electrochemical sensing applications such as neuronal scanning.