JSSS Journal of Sensors and Sensor Systems JSSS J. Sens. Sens. Syst. 2194-878X Copernicus Publications Göttingen, Germany 10.5194/jsss-2-157-2013 Novel fully-integrated biosensor for endotoxin detection via polymyxin B immobilization onto gold electrodes Zuzuarregui A. 1 Arana S. 1 2 Pérez-Lorenzo E. 1 2 Sánchez-Gómez S. 3 4 Martínez de Tejada G. 3 Mujika M. 1 2 CEIT and Tecnun (University of Navarra), Paseo Manuel Lardizábal No. 15, 20018 San Sebastián, Spain CIC microGUNE, Goiru Kalea 9, 20500 Arrasate-Mondragon, Spain Department of Microbiology and Parasitology, University of Navarra, Irunlarrea 1, 31008, Spain current address: Immunoadjuvant unit, Bionanoplus, Noain, Spain 24 09 2013 2 2 157 164 Copyright: © 2013 A. Zuzuarregui et al. 2013 This work is licensed under the Creative Commons Attribution 3.0 Unported License. To view a copy of this licence, visit https://creativecommons.org/licenses/by/3.0/ This article is available from https://jsss.copernicus.org/articles/2/157/2013/jsss-2-157-2013.html The full text article is available as a PDF file from https://jsss.copernicus.org/articles/2/157/2013/jsss-2-157-2013.pdf

In this paper an electrochemical endotoxin biosensor consisting of an immobilized lipopolysaccharide (LPS) ligand, polymyxin B (PmB), is presented. Several parameters involved both in the device fabrication and in the detection process were analyzed to optimize the ligand immobilization and the interaction between PmB and LPS, aiming at increasing the sensitivity of the sensor. Different electrochemical pre-treatment procedures as well as the functionalization methods were studied and evaluated. The use of a SAM (self-assembled monolayer) to immobilize PmB and the quantification of the interactions via cyclic voltammetry allowed the development of a robust and simple device for in situ detection of LPS. Thus, the biosensor proposed in this work intends an approach to the demanding needs of the market for an integrated, portable and simple instrument for endotoxin detection.

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