A Potentiometric Sensor for Highly Selective and Sensitive Determination of Flurazepam in Pharmaceutical and Biological Samples Based on Molecularly Imprinted Polyaniline as the Ionophore

In this study, a molecularly imprinted polymer (MIP) specifically designed for flurazepam (FZM) was synthesized using polyaniline as the base material. This polymer was subsequently utilized as an ionophore in the fabrication of a potentiometric sensor aimed at the precise determination of FZM concentrations. The optimal sensor composition was determined to consist of ۸% ionophore, ۲% sodium tetraphenylborate (NaTPB), ۳۰% polyvinyl chloride (PVC), and ۶۰% dioctyl phthalate (DOP). This particular formulation yielded the highest Nernstian response, with a slope of ۵۹.۶ millivolts per decade. The developed sensor exhibited a broad linear detection range, spanning from ۱.۰×۱۰⁻⁸ to ۱.۰×۱۰⁻³ mol L⁻¹, and demonstrated an impressive detection limit as low as ۷.۰×۱۰⁻⁹ mol L⁻¹. Furthermore, the sensor's operational pH range was determined to be between ۳.۰ and ۸.۰, ensuring functionality across varying conditions. The response time of the sensor was remarkably rapid, requiring only ۵ seconds to stabilize, while its lifespan extended up to two months under optimal storage and usage conditions. To validate the practical utility of the proposed sensor, its performance was rigorously tested in both pharmaceutical formulations and biological samples. The results revealed %Recovery values within the range of ۹۷.۵% to ۱۰۵.۰%, signifying highly accurate and reliable performance in real-world applications. These findings underscore the effectiveness and potential applicability of the developed electrode for precise and efficient FZM determination in diverse sample matrices.

کلیدواژه ها:

Molecularly-imprinted polymer (MIP) Potentiometry ، Flurazepam ، Electrochemical sensor ، Polyaniline ، Ion selective electrode