title: Bioelectrochemical sensing of promethazine with bamboo-type multiwalled carbon nanotubes dispersed in calf-thymus double stranded DNA.
abstract: We report the quantification of promethazine (PMZ) using glassy carbon electrodes (GCE) modified with bamboo-like multi-walled carbon nanotubes (bCNT) dispersed in double stranded calf-thymus DNA (dsDNA) (GCE/bCNT-dsDNA). Cyclic voltammetry measurements demonstrated that PMZ presents a thin film-confined redox behavior at GCE/bCNT-dsDNA, opposite to the irreversibly-adsorbed behavior obtained at GCE modified with bCNT dispersed in ethanol (GCE/bCNT). Differential pulse voltammetry-adsorptive stripping with medium exchange experiments performed with GCE/bCNT-dsDNA and GCE modified with bCNTs dispersed in single-stranded calf-thymus DNA (ssDNA) confirmed that the interaction between PMZ and bCNT-dsDNA is mainly hydrophobic. These differences are due to the intercalation of PMZ within the dsDNA that supports the bCNTs, as evidenced from the bathochromic displacement of UV-Vis absorption spectra of PMZ and quantum dynamics calculations at DFTB level. The efficient accumulation of PMZ at GCE/bCNT-dsDNA made possible its sensitive quantification at nanomolar levels (sensitivity: (3.50±0.05)×10(8) μA·cm(-2)·M(-1) and detection limit: 23 nM). The biosensor was successfully used for the determination of PMZ in a pharmaceutical product with excellent correlation.
authors.affiliation: INFIQC (CONICET - Universidad Nacional de Córdoba), Departamento de Físicoquimica, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Ciudad Universitaria, 5000 Córdoba, Argentina.
authors.forename: Emiliano N
authors.initials: EN
authors.lastname: Primo
authors.affiliation: INFIQC (CONICET - Universidad Nacional de Córdoba), Departamento de Matemática y Física, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Ciudad Universitaria, 5000 Córdoba, Argentina.
authors.forename: M Belén
authors.initials: MB
authors.lastname: Oviedo
authors.affiliation: INFIQC (CONICET - Universidad Nacional de Córdoba), Departamento de Matemática y Física, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Ciudad Universitaria, 5000 Córdoba, Argentina.
authors.forename: Cristián G
authors.initials: CG
authors.lastname: Sánchez
authors.affiliation: INFIQC (CONICET - Universidad Nacional de Córdoba), Departamento de Físicoquimica, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Ciudad Universitaria, 5000 Córdoba, Argentina. Electronic address: rubianes@fcq.unc.edu.ar.
authors.forename: María D
authors.initials: MD
authors.lastname: Rubianes
authors.affiliation: INFIQC (CONICET - Universidad Nacional de Córdoba), Departamento de Físicoquimica, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Ciudad Universitaria, 5000 Córdoba, Argentina. Electronic address: grivas@fcq.unc.edu.ar.
authors.forename: Gustavo A
authors.initials: GA
authors.lastname: Rivas
mesh_terms: D000818:Animals; D018926:Anti-Allergic Agents / Q000032:analysis*; D015374:Biosensing Techniques / Q000295:instrumentation*; D002417:Cattle; D004247:DNA / Q000737:chemistry*; D055664:Electrochemical Techniques / Q000295:instrumentation; D004566:Electrodes; D004867:Equipment Design; D057230:Limit of Detection; D008958:Models, Molecular; D037742:Nanotubes, Carbon / Q000737:chemistry*; D011398:Promethazine / Q000032:analysis*
chemical_list: D018926:Anti-Allergic Agents; D037742:Nanotubes, Carbon; D004247:DNA; D011398:Promethazine
keywords: Bamboo carbon nanotube; Dispersion; Double stranded DNA; Electrochemical (bio)sensor; Intercalation; Promethazine