Electrochemiluminescence aptasensor of TiO 2 /CdS:Mn hybrids for ultrasensitive detection of cytochrome c

A novel electrochemiluminescence (ECL) aptasensor was proposed for ultrasensitive detection of cytochrome c (cyt c) using CdS:Mn quantum dot-modified TiO2 nanowires (NWs) as electrode. The Mn-doped CdS was deposited on the TiO2 NWs by successive ion layer adsorption and reaction (SILAR) as ECL emitter, on which thiol-modified aptamer of cyt c was attached via Cd–S bond. Due to the high photo-electrical transfer efficiency, the as-prepared aptasensor shows high selectivity and sensitivity towards cyt c with a detection limit of 9.5 fM and a linear range from 50 fM to 125 pM.