Spherical COFs decorated with gold nanoparticles and multiwalled carbon nanotubes as signal amplifier for sensitive electrochemical detection of doxorubicin

Doxorubicin (DOX) is an important clinical chemotherapeutic drug in cancer therapy, which is regrettably accompanied by dose-dependent cytotoxic effects. Therefore, monitoring DOX level in biological samples is essential for drug control and therapeutic regimen. Herein, a sensitive electrochemical sensor for DOX detection was developed based on a novel electrode material of covalent organic frameworks decorated with gold nano -particles and multiwalled carbon nanotubes (AuNPs@COFs-MWCNTs). The porous and spherical COFs was obtained via a simple solution infiltration method and electroactive AuNPs was confined on COFs by a facile hydrothermal method. In virtue of the porous property and large surface area of COFs, the obtained AuNPs@-COFs nanocomposite showed improved distribution of electroactive sites and increased affinity towards DOX, thereby enhancing the electrocatalytic activity towards DOX. Meanwhile, highly conductive MWCNTs was incorporated with AuNPs@COFs to guarantee the conductivity. Consequently, the obtained AuNPs@COFs-MWCNTs possessed enhanced electrocatalytic activity and conductivity, which could significantly amplify the DOX response signal. As a result, the sensor exhibited a better liner range for DOX from 0.08 mu M to 25 mu M with a low detection limit of 16 nM. And contributing to the satisfying selectivity, reproducibility and stability, the DOX sensor worked well in spiked human serum and cell lysate samples, showing potential application in monitoring DOX drug level in clinical biological samples.