title: Bioelectrochemistry of hemoglobin immobilized on a sodium alginate-multiwall carbon nanotubes composite film.
abstract: This study described the bioelectrochemistry of hemoglobin (Hb) at multiwall carbon nanotubes (MWCNTs) noncovalently functionalized with biopolymers of sodium alginate (SA). The characteristics of Hb/SA-MWCNTs composite film were studied by using FT-IR spectroscopy, UV-vis spectroscopy and electrochemical methods. Hb immobilized on SA-MWCNTs composite film retained its native secondary structure, achieved direct electron transfer with the apparent heterogeneous electron transfer rate constant (k(s)) of (9.54+/-0.883) s(-1) and showed excellent bioelectrocatalytic activity to the reduction of hydrogen peroxide. The amperometric response of the biosensor varied linearly with the H(2)O(2) concentration ranging from 40 to 200 microM, with a detection limit of 16.41x10(-6) M (S/N=3) and the good long-term stability. Finally, we applied this proposed method to investigate the concentration of hydrogen peroxide in real samples.
authors.affiliation: Center for Biomedical Materials and Engineering, Harbin Engineering University, Harbin 150001, China.
authors.forename: H Y
authors.initials: HY
authors.lastname: Zhao
authors.forename: W
authors.initials: W
authors.lastname: Zheng
authors.forename: Z X
authors.initials: ZX
authors.lastname: Meng
authors.forename: H M
authors.initials: HM
authors.lastname: Zhou
authors.forename: X X
authors.initials: XX
authors.lastname: Xu
authors.forename: Z
authors.initials: Z
authors.lastname: Li
authors.forename: Y F
authors.initials: YF
authors.lastname: Zheng
mesh_terms: D000327:Adsorption; D000464:Alginates / Q000737:chemistry*; D015374:Biosensing Techniques / Q000295:instrumentation*; D004563:Electrochemistry / Q000295:instrumentation* / Q000379:methods; D004566:Electrodes; D004867:Equipment Design; D019544:Equipment Failure Analysis; D020723:Glucuronic Acid / Q000737:chemistry; D006454:Hemoglobins / Q000737:chemistry*; D006603:Hexuronic Acids / Q000737:chemistry; D006861:Hydrogen Peroxide / Q000032:analysis* / Q000737:chemistry; D008567:Membranes, Artificial; D036103:Nanotechnology / Q000295:instrumentation / Q000379:methods; D037742:Nanotubes, Carbon / Q000737:chemistry* / Q000648:ultrastructure; D011485:Protein Binding; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity
chemical_list: D000464:Alginates; D006454:Hemoglobins; D006603:Hexuronic Acids; D008567:Membranes, Artificial; D037742:Nanotubes, Carbon; D020723:Glucuronic Acid; D006861:Hydrogen Peroxide