Impedimetric DNA Sensor Based on a Composite of Electrochemically Reduced Graphene Oxide and Polyproflavine...

A novel nanocomposite based on electrochemically reduced graphene oxide (ERGO) and electropolymerized polyproflavine (PPFL) was obtained within a "one-pot" synthesis from natural deep eutectic solvent (NADES). NADES consisted of citric acid, glucose, and water in a molar ratio of 1:1:6. The synthesis was carried out in potentiostatic mode by consequent potential application in cathodic and anodic areas. The composite was applied to develop the impedimetric DNA sensor for anthracycline determination. The sensor has provided linear range from 10 nM to 0.1 mM for doxorubicin, from 1 pM to 10 nM for epirubicin, and from 10 pM to 10 nM for idarubicin, with the limit of detection 3 nM, 1 pM, and 5 pM, respectively. The concentrations of doxorubicin below 10 nM did not have any other influence on epirubicin and idarubicin determination despite their molecular structure similarity. The sensor developed was used for the determination of anticancer medications, such as doxorubicin, epirubicin, and idarubicin, in their standard solutions, pharmaceuticals, artificial, and human urine samples. It is worth noting that the additions of mannitol and lactose, which are the stabilizers of the pharmaceuticals, exhibited an interfering effect on the sensor response.