“…The surface plasmon resonance sensor employing a DNA aptamer can measure the concentration of an antineoplastic drug, irinotecan, with a high selectivity in a range of 0.2–12.8 μM [ 6 ]. More excellent sensitivity is described in a surface-enhanced Raman spectroscopy method with a direct anticoagulant, edoxaban, (limit of quantification: 1 pM) [ 7 ]. An electrode based on CeBiO x nanofiber detects acetaminophen with a low detection limit of 0.2 μM [ 8 ].…”