Glycoprotein imprinted RGO-starch nanocomposite modified EQCM sensor for sensitive and specific detection of transferrin

In this paper an electrochemical sensor for transferrin was developed by anchoring molecularly imprinted polymers (MIPs) on surface of gold coated quartz crystal microbalance (EQCM) using starch nanoparticles (Starch NP) - reduced graphene oxide (RGO) nanocomposite as polymeric format for first time. The nano MIP sensor was developed by electrodeposition of Starch NP-RGO nanocomposite on EQCM electrode in presence of template transferrin. Due to the location of imprinted sites on surface and high specific surface area, analyte molecules have good accessibility and high binding affinity to template molecule thus yielding highly sensitive and efficient signal. Under optimized conditions, the change in frequency of modified electrode coated quartz crystal electrode showed linear dynamic ranges (1–10 μM) using EQCM method. The limit of detection 20 ppb (EQCM) without any cross reactivity and matrix effect indicates high sensitivity and selectivity for transferrin. The sensor was appreciably selective to transferrin in presence of possible interferrents. The relative standard deviation for determination was 5.23%. On the basis of speediness and sensitivity, the sensor is reusable and shows a great improvement in selectivity and adsorption capacity over other sensors.