Electrogenerated chemiluminescence has attracted much attention in various fields of bioanalysis due to the potential remarkably high sensitivity, extremely wide dynamic range and excellent controllability and by taking the advantage of the selectivity of the biological recognition elements the ECL technique was applied as a powerful analytical method for ultrasensitive detection of biomolecules.1 In bioaffinity sensors the selective and strong binding of target biomolecules such as antibodies (Ab), aptamers or oligonucleotides, membrane receptors, with a target analyte used to produce a measurable signal. So, a typical bioaffinity sensing system includes of two main elements, one responsible for biomolecule recognition and the other for readout the corresponding signal. So, development of various platform for immobilization of different recognition elements and luminophores is a challenge for improving of analytical characteristics of ECL based sensors and biosensors. Due to unique chemical and physical properties of nanomaterials such as broad absorption, narrow and symmetrical emission, high quantum yield and excellent photostability, they are a good candidate as platform, emitter and coreactants in ECL based sensing systems. In our research group recently we applied various nanomaterials including, Cd and Ni nanoclusters, CdS and CdTe quantum dots, EuS nanoclusters and Ru-complex immobilized onto dendrimers as luminophores and different nanomaterials such as Fe3O4 @SiO2 nanoparticles, graphene oxide , graphdyine nanosheets and metal organic framworks as platform and carbon dots as correactant for fabrication of ECL biosensors. The proposed ECL biosensors have been used for detection of various biomarkers including cratenine, hepatitis B virus, HIV-1 gene, and CA19-9 tumor marker.2-6 Furthermore, with improving of molecular design in ECL platforms we introduced sensitive and selective ECL biosensors for simultaneous detection of tumor markers such as CA125, CA15-5 and CEA and AFP in clinical samples,7,8 and integration of electrochemical biosensors in clinical laboratories and nanomedicine is investigated.
