title: Direct electrochemistry of hemoglobin and biosensing for hydrogen peroxide using a film containing silver nanoparticles and poly(amidoamine) dendrimer.
abstract: A new architecture for a biosensor is proposed using a glassy carbon electrode (GCE) modified with hemoglobin (Hb) and silver nanoparticles (AgNPs) encapsulated in poly(amidoamine) dendrimer (PAMAM). The biosensors were characterized using ultraviolet-visible spectroscopy, ζ-potential and cyclic voltammetry to investigate the interactions between Hb, AgNPs and the PAMAM film. The biosensor exhibited a well-defined cathodic peak attributed to reduction of the Fe(3+) present in the heme group in Hb, as revealed by cyclic voltammetry in the presence of O2. An apparent heterogeneous electron transfer rate of 4.1s(-1) was obtained. The Hb-AgNPs-PAMAM/GCE third generation biosensor was applied in the amperometric determination of hydrogen peroxide over the linear range from 6.0 × 10(-6) to 9.1 × 10(-5)mol L(-1) with a detection limit of 4.9 × 1 0(-6)mol L(-1). The proposed method can be extended to immobilize and evaluate the direct electron transfer of other redox enzymes.
authors.affiliation: Nanomedicine and Nanotoxicology Group, Instituto de Física de São Carlos, Universidade de São Paulo, 13566-390 São Carlos, SP, Brazil; Departamento de Química, Universidade Federal de São Carlos, 13565-970 São Carlos, SP, Brazil.
authors.forename: Marina
authors.initials: M
authors.lastname: Baccarin
authors.affiliation: Departamento de Química, Universidade Federal de São Carlos, 13565-970 São Carlos, SP, Brazil; Departamento de Ciências da Natureza, Matemática e Educação, Universidade Federal de São Carlos, 13600-970 Araras, SP, Brazil. Electronic address: brunocj@ymail.com.
authors.forename: Bruno C
authors.initials: BC
authors.lastname: Janegitz
authors.affiliation: Nanomedicine and Nanotoxicology Group, Instituto de Física de São Carlos, Universidade de São Paulo, 13566-390 São Carlos, SP, Brazil.
authors.forename: Rodrigo
authors.initials: R
authors.lastname: Berté
authors.affiliation: Departamento de Química, Universidade Federal de São Carlos, 13565-970 São Carlos, SP, Brazil.
authors.forename: Fernando Campanhã
authors.initials: FC
authors.lastname: Vicentini
authors.affiliation: Faculty of Science and Engineering, School of Chemistry and the Environment, Division of Chemistry and Environmental Science, Manchester Metropolitan University, Chester Street, Manchester M15GD, UK.
authors.forename: Craig E
authors.initials: CE
authors.lastname: Banks
authors.affiliation: Departamento de Química, Universidade Federal de São Carlos, 13565-970 São Carlos, SP, Brazil.
authors.forename: Orlando
authors.initials: O
authors.lastname: Fatibello-Filho
authors.affiliation: Nanomedicine and Nanotoxicology Group, Instituto de Física de São Carlos, Universidade de São Paulo, 13566-390 São Carlos, SP, Brazil.
authors.forename: Valtencir
authors.initials: V
authors.lastname: Zucolotto
mesh_terms: D015374:Biosensing Techniques / Q000379:methods*; D055664:Electrochemical Techniques; D006454:Hemoglobins / Q000737:chemistry*; D006801:Humans; D006861:Hydrogen Peroxide / Q000032:analysis* / Q000097:blood; D057230:Limit of Detection; D016014:Linear Models; D053768:Metal Nanoparticles / Q000737:chemistry*; D011073:Polyamines / Q000737:chemistry*; D012834:Silver / Q000737:chemistry*
chemical_list: D006454:Hemoglobins; C531249:Poly(amidoamine); D011073:Polyamines; D012834:Silver; D006861:Hydrogen Peroxide
keywords: Direct electron transfer; Hemoglobin; Hydrogen peroxide; Silver nanoparticles; Third generation biosensor