A nanocomposite prepared from reduced graphene oxide, gold nanoparticles and poly(2-amino-5-mercapto-1,3,4-thiadiazole) for use in an electrochemical sensor for doxorubicin

A nanocomposite was prepared with reduced graphene oxide, gold nanoparticles and an electropolymerized film made from 2-amino-5-mercapto-1,3,4-thiadiazole. An electrochemical sensor for doxorubicin (DOX) was constructed by modifying a glassy carbon electrode (GCE) with the nanocomposite. The modified GCE was studied by electrochemical techniques which showed it to enable highly sensitive sensing of DOX. Response (typically measured at a typical working potential of -0.56 V vs. Ag/AgCl) is linear in the 30 pM to 30 nM and 30 nM to 30 mu M DOX concentration ranges, with a limit of detection (LOD) of 9 pM (at an S/N ratio of 3). The method was applied to the determination of DOX in serum and gave recoveries that ranged between 92 and 108%.