Molecularly imprinted polymer-based core-shells (solid vs hollow) @ pencil graphite electrode for electrochemical sensing of certain anti-HIV drugs

•Fabrication of a new molecularly imprinted polymer (MIP) decorated core-shells (solid and hollow) as a sensing material for anti-HIV drugs, lamivudine and zidovudine.•This analysis is performed in real samples, without any cross-reactivity and false-positives.•Hollow core-shells MIP was found better than solid core-shells MIP in terms of typical behavior, akin to CNTs, HCs-MIPs undergo rapid diffusion of test analyte across the inner and outer surfaces in cooperation with the molecular exchange between analyte molecules.

The present work describes a new, simple, and easy method for the fabrication of molecularly imprinted polymer-based core-shells (solid and hollow) @ pencil graphite electrode for sensing anti-HIV drugs, lamivudine and zidovudine, in real samples. For this, an imprinted polymer was developed on the surface of vinylated silica nanospheres to obtain modified solid as well as hollow core-shells. In this work, respective electrodics in terms of analyte diffusion for binding and electrode kinetics of both modified solid and hollow core-shells were compared using a ferricyanide probe with cyclic voltammetric and differential pulse anodic stripping voltammetric methods of transduction. Whereas modified solid core-shells evolved unilateral diffusion of probe/analyte molecules, the corresponding hollow core-shells were found to be relatively better owing to their bilateral diffusions into molecular cavities. Indirect detections of electroinactive targets chosen were feasible with the help of probe using imprinted hollow core shells modified electrode with limits of detection as low as 2.23 and 1.26 (aqueous sample), 2.45 and 1.88 (blood serum), and 2.52 and 1.77 ng mL−1 (pharmaceutics) for lamivudine and zidovudine, respectively.

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