Fullerene Black Modified Screen Printed Electrodes for the Quantification of Acetaminophen and Guanine

Fullerene Black (FB) and Extracted Fullerene Black (EFB) were used in modified screen‐printed electrodes producing electrochemical transducers (FB‐SPEs and EFB‐SPEs). A complete electrochemical study was performed and the best results are obtained working with FB‐SPEs, especially in terms of: 1. improved electron‐transfer kinetic mechanisms and 2. sensitivity and selectivity toward Acetaminophen (Ac) and Guanine (G). These latter represent two important electro‐active targets to quantify in medicine field application, because: Ac is a preferred alternative (as analgesic‐antipyretic agent) to aspirin, particularly for patients who cannot tolerate aspirin; the oxidation signal of G is useful for the fabrication of emerging analytical tools, such as DNA chipsand user‐friendly diagnostic devices. Ac and G are quantify by using FB‐SPEs electrochemical devices, with an extended linearity (1–300 μM for Ac; 0.1–300 μM for G), an excellent sensitivity (2.82 μA μM⁻¹ cm⁻² in the case of Ac; and 0.183 μA μM⁻¹ cm⁻² in the case of G), a low detection limit (0.01 μM for Ac; 0.005 μM for G), a very good reproducibility (both: intra‐; inter‐electrodes reproducibility RSD % ranging from 0.3–0.5 for Ac; and 0.50–0.85 for G) and a very fast response time (6 s for Ac; 5 s in the case of G). In addition, high selectivity is obtained at FB‐SPEs, meaning that the FB‐SPEs electrochemical transducers are suitable to simultaneously quantify Ac and G in real samples, having several different (highly concentrated) interference.