Sandwich-type electrochemical immunosensor for CEA detection using magnetic hollow Ni/C@SiO2 nanomatrix and boronic acid functionalized CPS@PANI@Au probe.

A sandwich-type electrochemical immunosensor was developed for the detection of CEA where hollow magnetic silica coated nickel/carbon (Ni/C@SiO2) nanocomposites was used as an immobilized carrier and gold nanoparticle-coated PANI microsphere (CPS@PANI@Au) as electrochemical transducer. Magnetic assembly of Ni/C@SiO2 nanocomposites allow easy separation and assembly which eliminates the further modification process. In addition, the prepared CPS@PANI@Au possess good biocompatibility, and electrical conductivity. The fabricated immunosensor show excellent sensing performance including a wide dynamic range from 0.006 to 12.00 ng mL-1 and low detection limit at 1.56 pg mL-1. Moreover, this sensor shows superior selectivity with excellent reliability and reproducibility which might lead into easier implementation in clinical setting.