title: Anodic porous alumina as mechanical stability enhancer for LDL-cholesterol sensitive electrodes.
abstract: In this work, to improve the mechanical stability of electrodes based on P450scc for LDL-cholesterol detection and measure, anodic porous alumina (APA) was used. This inorganic matrix, which pores can be tuned in diameter modifying the synthesis parameters, was realized with cavities 275 nm wide and 160 microm deep (as demonstrated with AFM and SEM measurement), to allow the immobilization of P450scc macromolecules preserving their electronic sensitivity to its native substrate, cholesterol. Even if the sensitivity of the APA+P450scc system was slightly reduced with respect to the pure P450scc system, the readout was stable for a much longer period of time, and the measures remained reproducible inside a proper confidentiality band, as demonstrated with several cyclic voltammetry measures. To optimize the adhesion of P450scc to APA, a layer of poly-L-lysine, a poly-cathion, was successfully implemented as intermediate organic structure.
authors.affiliation: Fondazione Elba, Piazza SS Apostoli 66, 00100, Rome, Italy.
authors.forename: Enrico
authors.initials: E
authors.lastname: Stura
authors.forename: Debora
authors.initials: D
authors.lastname: Bruzzese
authors.forename: Federica
authors.initials: F
authors.lastname: Valerio
authors.forename: Valentina
authors.initials: V
authors.lastname: Grasso
authors.forename: Pietro
authors.initials: P
authors.lastname: Perlo
authors.forename: Claudio
authors.initials: C
authors.lastname: Nicolini
mesh_terms: D000537:Aluminum Oxide; D015374:Biosensing Techniques / Q000295:instrumentation*; D008078:Cholesterol, LDL / Q000032:analysis*; D003577:Cytochrome P-450 Enzyme System; D004563:Electrochemistry; D004566:Electrodes; D016062:Porosity
chemical_list: D008078:Cholesterol, LDL; D003577:Cytochrome P-450 Enzyme System; D000537:Aluminum Oxide