Electroactive Prussian Blue Encapsulated Iron Oxide Nanostructures for Mediator‐Free Cholesterol Estimation

Abstract

Iron oxide nanoparticles of size ∼10 nm have been encapsulated into four nanometer thick shells of Prussian blue and were then electrophoretically deposited onto an indium tin oxide substrate. The immobilization of cholesterol oxidase has been done onto the nanostructured film to investigate the kinetic parameters and biosensing characteristics. The fabricated bioelectrode exhibits an electron transfer coefficient and a charge transfer rate constant of 0.45 and 45.15 s−1, respectively. Direct electron transfer properties of the nanostructured film result in 3rd generation cholesterol biosensor. The bioelectrode exhibits high sensitivity (2.15 mAM−1 cm−2), a low Kmapp value (0.07 mM), good stability and high selectivity towards cholesterol.

Functionalized magnetic nanomaterials for electrochemical biosensing of cholesterol and cholesteryl palmitate

“…Other examples of cholesterol biosensing which exploit nanoparticles include nanoscale Pt nanoparticles and graphene [17]. Prussian blue encapsulated iron oxide nanostructures [18], a paper based cholesterol biosensor based on graphene/polyvinylpyrroliidone/polyaniline nanocomposites [19] and core shell silica nanocomposite, was used to immobilize cholesterol oxidase, esterase and horseradish peroxidase [20].…”