Electrochemical (bio)sensors based on the use of carbon nanomaterials

GUSTAVO A. RIVAS; FABIANA A. GUTIERREZ; EMILIANO N. PRIMO; AURELIEN GASNIER; MARCOS EGUÍLAZ; ALEJANDRO GUTIÉRREZ; GUILLERMINA LUQUE; MARÍA L. PEDANO; MARCELA C. RODRIGUEZ; NANCY F. FERREYRA; M. DOLORES RUBIANES

Angra dos Reis

Congreso; 16th Topical Meeting of the International Society of Electrochemistry Electrochemical Properties and Applications of Advanced Carbon Materials; 2015

Electrochemistry and Electroanalytical Division of the Brazilian Chemical Society

This presentation is focused on the discussion of new strategies for the design of (bio)electroanalytical platforms devoted to the sensitive and selective quantification of biomarkers based on the use of carbon nanomaterials. Special attention will be given to the critical selection of the molecules used to functionalize the carbon nanostructures in order to obtain nanomaterials with biorecognition, preconcentration or electrical properties that make possible the efficient sensing of important bioanalytes. We discuss the advantages of electrochemical (bio)sensors obtained by modification of glassy carbon electrodes (GCE) with multiwalled carbon nanotubes (MWCNT) non-covalently functionalized by dispersion in polyhistidine (Polyhis), calf-thymus double stranded DNA (dsDNA), and polylysine (Plys). The dispersions were obtained by mixing the MWCNT with the given polymer (prepared in 50% ethanol solution) followed by sonication for a given time. The (bio)sensors were obtained by drop-coating on polished GCE and further evaporation of the solvent at room temperature. The resulting electrodes (GCE/CNT-polymer) were used for (bio)sensing of : I) the hybridization event using GCE/CNT-Plys taking the system oligo(dG)-oligo(dC) as model; II) glucose using GCE/CNT-polymer modified by self-assembling of glucose oxidase (GOx); III) Cu(II) using GCE/CNT-Polyhis; IV)promethazine using GCE/MWCNT-dsDNA. The modification of GCE with SWCNTs covalently functionalized with Polylys, lysine, tyrosine, and cysteine was also investigated to obtain analytical platforms for the quantification of glucose, dopamine and heavy metals, respectively. Chemically reduced graphene oxide obtained from the oxidation of graphite and graphene nanoribons obtained from the oxidation of MWCNTs were also used for the construction of (bio)sensing electrochemical platforms. The reduced graphene oxide (RGO) was incorporated in a composite material containing graphite and mineral oil and the resulting electrode was used for the successful quantification of NADH and Do in the presence of ascorbic acid. The usefulness of graphene nanoribons was also demonstrated in connection with the highly successful quantification of dopamine either in solution or by adsorptive stripping with differential pulse voltammetry transduction and medium exchange. In summary, the proposed (bio)sensors demonstrate that the judicious and intimate coupling of a suitable (bio)molecule and an electrochemical transducer efficiently modified with carbon nanomaterials makes possible the development of highly sensitive and selective bioanalytical devices.