title: Colorimetric cholesterol sensor based on peroxidase like activity of zinc oxide nanoparticles incorporated carbon nanotubes.
abstract: A sensitive and selective colorimetric method based on the incorporation of zinc oxide nanoparticles (ZnO NPs) on the surface of carbon nanotubes (CNTs) was shown to posses synergistic peroxidase like activity for the detection of cholesterol. The proposed nanocomposite catalyzed the oxidation of 2,2'-azino-bis(3-ethylbenzthiazoline-6-sulfonic acid (ABTS) in the presence of hydrogen peroxide (H2O2) to produce a green colored product which can be monitored at 405 nm. H2O2 is the oxidative product of cholesterol in the presence of cholesterol oxidase. Therefore, the oxidation of cholesterol can be quantitatively related to the colorimetric response by combining these two reactions. Under the optimal experimental conditions, the colorimetric response was proportional to the concentration of cholesterol in the range of 0.5-500 nmol/L, with a detection limit of 0.2 nmol/L. The applicability of the proposed assays was demonstrated for the determination of cholesterol in milk powder samples with good recovery results.
authors.affiliation: Interdisciplinary Research Centre in Biomedical Materials (IRCBM), COMSATS Institute of Information Technology (CIIT), Lahore, Pakistan. Electronic address: akhtarhayat@ciitlahore.edu.pk.
authors.forename: Akhtar
authors.initials: A
authors.lastname: Hayat
authors.affiliation: Institute of Chemical Sciences, Bahauddin Zakariya University, Multan, Pakistan.
authors.forename: Waqar
authors.initials: W
authors.lastname: Haider
authors.affiliation: Institute of Chemical Sciences, Bahauddin Zakariya University, Multan, Pakistan.
authors.forename: Yousuf
authors.initials: Y
authors.lastname: Raza
authors.affiliation: BAE: Biocapteurs-Analyses-Environnement, Universite de Perpignan Via Domitia, 52 Avenue Paul Alduy, Perpignan Cedex 66860, France.
authors.forename: Jean Louis
authors.initials: JL
authors.lastname: Marty
mesh_terms: D000818:Animals; D052160:Benzothiazoles / Q000737:chemistry; D040761:Biomimetic Materials / Q000737:chemistry*; D015374:Biosensing Techniques / Q000379:methods*; D002784:Cholesterol / Q000032:analysis*; D002789:Cholesterol Oxidase / Q000737:chemistry / Q000378:metabolism; D003116:Color; D003124:Colorimetry / Q000379:methods*; D006861:Hydrogen Peroxide / Q000737:chemistry; D008892:Milk / Q000737:chemistry; D008958:Models, Molecular; D053758:Nanoparticles / Q000737:chemistry; D037742:Nanotubes, Carbon / Q000737:chemistry*; D010084:Oxidation-Reduction; D010544:Peroxidases / Q000378:metabolism*; D011487:Protein Conformation; D013451:Sulfonic Acids / Q000737:chemistry; D015034:Zinc Oxide / Q000737:chemistry*
chemical_list: D052160:Benzothiazoles; D037742:Nanotubes, Carbon; D013451:Sulfonic Acids; C002502:2,2'-azino-di-(3-ethylbenzothiazoline)-6-sulfonic acid; D002784:Cholesterol; D006861:Hydrogen Peroxide; D002789:Cholesterol Oxidase; D010544:Peroxidases; D015034:Zinc Oxide
keywords: Cholesterol detection; Colorimetric assays; Enzyme mimic; Synergic effect; ZnO incorporated carbon nanotubes