title: Flower like Bi structures on Pt surface facilitating effective cholesterol biosensing.
abstract: This work demonstrates effective biosensing of cholesterol with the help of an efficient inorganic H2O2 transducer based on Pt-Bi combined with the organic enzyme platform. It could be shown that the Bi (bismuth) adatoms modified Pt (platinum) surface displays enhanced catalytic oxidation of H2O2 at neutral pH and the catalytic oxidation of H2O2 occurs at a lower potential of 0.25V vs NCE (normal calomel electrode). The sensing platform is highly sensitive and shows linear response towards [H2O2] in the absence of any redox mediator or enzyme. The H2O2 sensing platform, further modified with cholesterol oxidase led to cholesterol biosensing with a sensitivity of 3.41μAmM(-1)cm(-2). The apparent Michaelis-Menten constant (Km(app)) was calculated to be 0.43mM which indicates high binding affinity with the substrate. The cholesterol biosensor does not suffer from the interferences due to other common electroactive species and is highly stable.
authors.affiliation: CSIR-Central Electrochemical Research Institute, Karaikudi 630006, Tamilnadu, India.
authors.forename: Soorya
authors.initials: S
authors.lastname: V C
authors.affiliation: CSIR-Central Electrochemical Research Institute, Karaikudi 630006, Tamilnadu, India. Electronic address: sheelaberchmans@yahoo.com.
authors.forename: Sheela
authors.initials: S
authors.lastname: Berchmans
mesh_terms: D001426:Bacterial Proteins / Q000737:chemistry*; D015374:Biosensing Techniques / Q000379:methods*; D001729:Bismuth / Q000737:chemistry*; D002784:Cholesterol / Q000032:analysis*; D002789:Cholesterol Oxidase / Q000737:chemistry*; D006861:Hydrogen Peroxide / Q000737:chemistry; D015394:Molecular Structure; D010984:Platinum / Q000737:chemistry*; D013302:Streptomyces / Q000201:enzymology*
chemical_list: D001426:Bacterial Proteins; D010984:Platinum; D002784:Cholesterol; D006861:Hydrogen Peroxide; D002789:Cholesterol Oxidase; D001729:Bismuth
keywords: Bi-Pt catalytic electrode; Bismuth adlayers; Cholesterol biosensor; Hydrogen peroxide transduction; Michaelis-Menten constant