Construction of an electrochemical aptamer-based sensors for rapid quantification of the anticancer drug imatinib in blood to improve drug bioavailability at microdoses.

Imatinib (Ima), as a commonly used anticancer drug for the clinical treatment of leukemia and gastrointestinal mesenchymal stromal tumour, requires timely monitoring of patients' blood concentration to ensure efficacy while reducing complications and achieving precision medicine due to its narrow therapeutic window (1-5 μM) and the varying sensitivity and resistance of different patients to Ima. However, traditional assays are slow and cumbersome, so improved and innovative platforms for monitoring Ima in the clinic are necessary. In this work, a nanoporous electrochemical aptamer-based (E-AB) sensor was designed for the detection of Ima and imatinib mesylate (Ima-Mes) in blood. Apt-37, a high-affinity and conformationally variable aptamer, was screened by molecular docking simulation calculations and circular dichroism (CD) for the construction of the E-AB sensor. The sensor detected Ima and Ima-Mes in the range of 0.1 μM-1 mM, and the recoveries in spiked blood samples were in the range of 70.7 %-104.6 % and 74.8 %-113.9 %, respectively. The precision and accuracy of the E-AB sensor for measuring Ima-Mes concentration in blood was similar to the standard LC-MS method. These results demonstrate that the developed E-AB sensor is an effective tool for rapid monitoring of Ima and Ima-Mes in blood.