Cu-Au nanocrystals functionalized carbon nanotube arrays vertically grown on carbon spheres for highly sensitive detecting cancer biomarker.

A three-dimensional hierarchical nanohybrid based on Cu-Au bimetallic nanocrystals integrated carbon nanotube arrays vertically grown on carbon spheres was successfully developed as an active platform for sensing application. Such nanohybrid can provide abundant active sites and act as an exceptional platform for immobilizing highly dense and well-dispersed carcinoembryonic antibody (anti-CEA) to sensitively detect CEA, an emerging biomarker of various cancer diseases. Due to the unique nanoarchitecture with altered electronic structure of Cu-Au bimetallic catalyst and enhanced interactions between components, such nanohybrid based biosensor demonstrated excellent electrochemical performance towards CEA detection with great sensitivity, wide linear detection range (0.025-25 ng/mL), very low limit of detection (0.5 pg/mL), and good selectivity. The results imply that this sensor has great potential to offer essential information for cancer diagnosis and management with great clinical importance.