Título

Development of a biosensor based on a-SixC1-x:H to detect enterotoxigenic Escherichia coli

Autor

JOSE LUIS HERRERA CELIS

Colaborador

CLAUDIA REYES BETANZO (Asesor de tesis)

ABDU ORDUÑA DIAZ (Asesor de tesis)

Nivel de Acceso

Acceso Abierto

Resumen o descripción

The food industry and clinical analysis, among other sectors, require the development of techniques and devices that detect pathogens, while the development of implantable devices needs biocompatible materials with low degradation in biological environment to increase the lifetime of the device. Throughout this work, hydrogenated amorphous silicon-carbon (a-SixC1-x:H) alloy is proposed, obtained, characterized and incorporated into the development of a proposed interdigitated microelectrode array (PIMA) to capture the bacteria of enterotoxigenic Escherichia coli (E. coli, ETEC). a-SixC1-x:H is obtained by the technique of plasma-enhanced chemical vapor deposition (PECVD) using methane and silane as precursor gases under high hydrogen dilution and low power density in order to improve its biocompatibility. Furthermore, considering the projection of the material in biosensors and the effect of the precursor gas ratio on the material properties, films with different precursor gas ratio were deposited and characterized. The result was a set of films with low density of CHn groups, which was also subject under studied.

Simultaneously, the PIMA was designed and simulated using CoventorWare® software. Structurally the PIMA incorporates two layers of a-SixC1-x:H, one between and another on microelectrode, on which a biofunctionalization layer is formed. The aim of this layer is to capture the bacteria by affinity interactions. Functionally the PIMA is a transducer based on electrical impedance, namely the capture of E. coli bacteria causes changes in the electrical properties of the medium between and on the microelectrodes of the array, which are associated with changes in electrical impedance. The simulations were made with the purpose of knowing the operation that the PIMA would have under operating conditions (with bacterial environment) and of analyzing the design aspects that could affect or increase the sensitivity of the array. One of the results of the simulations was that the conductivity of the layer of a-SixC1-x:H on microelectrodes should be as high as possible to reduce its effect on the sensitivity of the biosensor, therefore diborane as doping gas was incorporated during the depositions of some films, which were also characterized.

Editor

Instituto Nacional de Astrofísica, Óptica y Electrónica

Fecha de publicación

noviembre de 2016

Tipo de publicación

Tesis de doctorado

Versión de la publicación

Versión aceptada

Formato

application/pdf

Idioma

Inglés

Audiencia

Estudiantes

Investigadores

Público en general

Sugerencia de citación

Herrera-Celis J.L.

Repositorio Orígen

Repositorio Institucional del INAOE

Descargas

3620

Comentarios



Necesitas iniciar sesión o registrarte para comentar.