title: Poly(lactic acid)/Carbon Nanotube Fibers as Novel Platforms for Glucose Biosensors.
abstract: The focus of this paper is the development and investigation of properties of new nanostructured architecture for biosensors applications. Highly porous nanocomposite fibers were developed for use as active materials in biosensors. The nanocomposites comprised poly(lactic acid)(PLA)/multi-walled carbon nanotube (MWCNT) fibers obtained via solution-blow spinning onto indium tin oxide (ITO) electrodes. The electrocatalytic properties of nanocomposite-modified ITO electrodes were investigated toward hydrogen peroxide (H2O2) detection. We investigated the effect of carbon nanotube concentration and the time deposition of fibers on the sensors properties, viz., sensitivity and limit of detection. Cyclic voltammetry experiments revealed that the nanocomposite-modified electrodes displayed enhanced activity in the electrochemical reduction of H2O2, which offers a number of attractive features to be explored in development of an amperometric biosensor. Glucose oxidase (GOD) was further immobilized by drop coating on an optimized ITO electrode covered by poly(lactic acid)/carbon nanotube nanofibrous mats. The optimum biosensor response was linear up to 800 mM of glucose with a sensitivity of 358 nA·mM-1 and a Michaelis-Menten constant (KM) of 4.3 mM. These results demonstrate that the solution blow spun nanocomposite fibers have great potential for application as amperometric biosensors due to their high surface to volume ratio, high porosity and permeability of the substrate. The latter features may significantly enhance the field of glucose biosensors.
authors.affiliation: PPGCEM, Departamento de Engenharia de Materiais (DEMA), Universidade Federal de São Carlos (UFSCAR), Rodovia Washington Luis, km 235, Monjolinho, 13.565-905, São Carlos, SP, Brazil. julianoufmg@yahoo.com.br.
authors.forename: Juliano Elvis
authors.initials: JE
authors.lastname: Oliveira
authors.affiliation: Laboratório Nacional de Nanotecnologia para o Agronegócio (LNNA), Embrapa Instrumentação (CNPDIA), Rua XV de Novembro, 1452, Centro, 13.560, 970 São Carlos, SP, Brazil. mattoso@cnpdia.embrapa.br.
authors.forename: Luiz Henrique Capparelli
authors.initials: LH
authors.lastname: Mattoso
authors.affiliation: Departamento de Engenharia de Materiais (DEMAT), Universidade Federal da Paraíba (UFPB), Cidade Universitária, 58.051-900, João Pessoa, PB, Brazil. eliton_s@yahoo.com.
authors.forename: Eliton Souto
authors.initials: ES
authors.lastname: Medeiros
authors.affiliation: Laboratório de Nanomedicina e Nanotoxicologia (LNN), Instituto de Física de São Carlos, Universidade de São Paulo, 13.560-970, P.O. Box 369, São Carlos, SP, Brazil. zuco@ifsc.usp.br.
authors.forename: Valtencir
authors.initials: V
authors.lastname: Zucolotto