title: Nanostructured sensor based on carbon nanotubes and clavanin A for bacterial detection.
abstract: Unusual methods for specific detection of pathogenic bacteria are becoming key points for control and identification of problems related to health and (bio)safety. In this context, this work aims to propose a new approach for the development of nanostructured biosensors based on carbon nanotubes (CNTs) and antimicrobial peptides for bacterial detection. Firstly, the antimicrobial peptide clavanin A (ClavA) was chemically immobilized on CNTs and surface-immobilized ClavA was used to detect Klebsiella pneumoniae, Enterococcus faecalis, Escherichia coli and Bacillus subtilis in a direct assay format. We used electrochemical impedance spectroscopy technique to evaluate the effectiveness and sensitivity of the ClavA-based biosensors by measuring the modifications in their electrochemical responses before and after incubation in presence of different bacteria concentrations. The biosensor was able to discriminate between bacteria concentrations in the 10(2)-10(6)CFU mL(-1) range. Atomic force microscopy analysis confirmed the biosensor functionality for bacterial recognition. This new sensor system was capable of differentiating between Gram-positive and Gram-negative bacteria, since ClavA showed different affinities toward the pathogenic bacteria species.
authors.affiliation: Programa de Pós-Graduação em Inovação Terapêutica, Universidade Federal de Pernambuco, 50670-901 Recife, PE, Brazil; Departamento de Bioquímica, Universidade Federal de Pernambuco, 50670-901 Recife, PE, Brazil. Electronic address: csrandrade@gmail.com.
authors.forename: César A S
authors.initials: CAS
authors.lastname: Andrade
authors.affiliation: Programa de Pós-Graduação em Inovação Terapêutica, Universidade Federal de Pernambuco, 50670-901 Recife, PE, Brazil.
authors.forename: Jéssica M
authors.initials: JM
authors.lastname: Nascimento
authors.affiliation: Centro Acadêmico de Vitória, Universidade Federal de Pernambuco, 55608-680 Vitória de Santo Antão, PE, Brazil.
authors.forename: Idjane S
authors.initials: IS
authors.lastname: Oliveira
authors.affiliation: Departamento de Bioquímica, Universidade Federal de Pernambuco, 50670-901 Recife, PE, Brazil.
authors.forename: Carlos V J
authors.initials: CVJ
authors.lastname: de Oliveira
authors.affiliation: Departamento de Física, Universidade Federal de Pernambuco, 50670-901 Recife, PE, Brazil.
authors.forename: Celso P
authors.initials: CP
authors.lastname: de Melo
authors.affiliation: Centro de Análise Proteômicas e Bioquímicas de Brasília, Universidade Católica de Brasília, Brasília, DF, Brazil; S-Inova, Pós-graduação em Biotecnologia, Universidade Católica Dom Bosco, Campo Grande, MS, Brazil.
authors.forename: Octávio L
authors.initials: OL
authors.lastname: Franco
authors.affiliation: Departamento de Bioquímica, Universidade Federal de Pernambuco, 50670-901 Recife, PE, Brazil.
authors.forename: Maria D L
authors.initials: MDL
authors.lastname: Oliveira
mesh_terms: D001419:Bacteria / Q000145:classification / Q000302:isolation & purification*; D015374:Biosensing Techniques; D001798:Blood Proteins / Q000737:chemistry*; D058266:Dielectric Spectroscopy; D018625:Microscopy, Atomic Force; D049329:Nanostructures; D037742:Nanotubes, Carbon
chemical_list: D001798:Blood Proteins; D037742:Nanotubes, Carbon; C106713:clavanin A
keywords: Antimicrobial peptides; Bacteria; Biosensor; Carbon nanotubes; Electrochemical impedance spectroscopy