Development of surface imprinted nanospheres using the inverse suspension polymerization method for electrochemical ultra sensing of dacarbazine

A new ultra sensing molecularly imprinted polymer beads modified pencil graphite electrode was fabricated, with the help of the inverse suspension polymerization technique, for ascertaining the adequate supplementation of dacarbazine in the cancer treatment. The inverse suspension polymerization technique was beneficial in obtaining surface imprinted polymer-based electrocatalytic nanospheres with narrow size distribution. These nanospheres were found to be superior to the corresponding microspheres and planar films, in terms of electrode kinetics and sensitivity, with the differential pulse anodic stripping voltammetric transduction. Herein, multiwalled carbon nanotubes functionalized ester links were invoked in between the imprinted nanospheres and the pencil graphite electrode surface to secure a stable coating and better electrodics. The proposed electrochemical sensor showed the imprinting factor and the analyte adsorption coefficient as high as 24.3 and 1.06 × 10⁹ L mol^-1, respectively. Furthermore, 16-fold and 4-fold faster electron transfer kinetics were observed with the imprinted nanospheres than the corresponding imprinted planar film and the microspheres based electrodes, respectively. The limits of detection [0.02 (aqueous), 0.02 (plasma), 0.01 (urine), and 0.03 ng mL^-1 (pharmaceutics), (3σ, RSD ≤ 0.23%)] of dacarbazine, realized with the imprinted polymer nanospheres, were free from any cross-reactivity and false-positive complications in aqueous, blood plasma, urine, and pharmaceutical samples.