Cyanocobalamin (VB₁₂) Bionic Enzyme-Assisted Photocatalytic Chain-Growth Polymerization for Detection of Lung Cancer Biomarkers

Cobalt-mediated radical polymerization is noted for itsgreat levelof control over the polymerization of acrylic and vinyl esters monomers,even at high molar mass. Vitamin B-12, a natural bionicenzyme cobalt complex, involves the conversion of organic halidesto olefins through chain-growth polymerization. In this work, thenotion of R-Co(III) free radical persistent free radical effect andvitamin B-12 circulation were first reported for the perceptionof ultralow abundance of microRNA-21, a lung cancer biomarker. Indeed,most Co-containing catalytic reactions can occur under mild conditionsdue to their minimal bond dissociation of the C-Co bond, withblue light irradiation. Based on the intrinsic stability of the vitaminB(12) framework and recycling of the catalyst, it is evidentthat this natural catalytic scheme has potential applications in medicinalchemistry and biomaterials. In addition, this strategy, combined withhighly specific recognition probes and vitamin B-12 circulation-mediatedchain-growth polymerization, has a detection limit as low as 910 aM.Furthermore, it is sensitive for sensing in serum samples containingbiomarkers and shows great potential for RNA selection and amplificationsensing in clinical samples.