Reduced graphene oxide-yttria nanocomposite modified electrode for enhancing the sensitivity of electrochemical genosensor

•Reduced graphene oxide-yttria nanocomposite is used as a genosensor platform.•High surface area and electron transfer nature of rGO:Y contribute to sensitivity.•The sensor exhibited a fine capability of sensing BRCA1 gene.•Sensor exhibited linear range from 10 attomolar (aM) to 1 nanomolar (nM).

Reduced graphene oxide-yttria nanocomposite (rGO:Y) is applied as electrochemical genosensor platform for ultrahigh sensitive detection of breast cancer 1 (BRCA1) gene for the first time. The sensor is based on the sandwich assay in which gold nanoparticle cluster labeled reporter DNA hybridize to the target DNA. Glassy carbon electrode modified with rGO-yttria serves as the immobilization platform for capture probe DNA. The sensor exhibited a fine capability of sensing BRCA1 gene with linear range of 10 attomolar (aM) to 1 nanomolar (nM) and a detection limit of 5.95 attomolar. The minimum distinguishable response concentration is down to the attomolar level with a high sensitivity and selectivity. We demonstrated that the use of rGO:Y modified electrode along with gold nanoparticle cluster (AuNPC) label leads to the highly sensitive electrochemical detection of BRCA1 gene.