Planar microsensors based on phenylboronic acid Self-Assembled Monolayers
|Martyna Jańczyk 1, Paweł Ćwik , Wojciech Wróblewski|
1. Warsaw University of Technology, Faculty of Chemistry, Noakowskiego 3, Warszawa 00-664, Poland
Electrochemical sensors found many applications as simple and selective analytical devices allowing fast and low-cost analysis in clinical diagnostics, environmental and process monitoring without the necessity of sample preparation. Their selectivity is mainly governed by the analyte recognition process – selective complexation of the analyte by the receptor molecules – occurring in the receptor layer. Therefore, the development of novel sensors requires the synthesis of selective receptors which could be introduced into polymeric films or immobilized on the surface of the transducers to form selective receptor layers.
Phenylboronic acid derivatives are widely used as selective receptors for developing new analytical methods for the determination of bioanalytes such as: sugars, neurotransmitters and some anions. Their high stability and especially their ability of fast and reversible ester formation with 1,2- and 1,3-diols have been applied to detect saccharides in solution (homogenous methods) as well as to design new optical saccharide sensors. In such approaches, fluorescent phenylboronic acids are usually applied to signal the binding process. Moreover, thiol-modified phenylboronic acids can be immobilized directly on the gold surface and form a self-assembled monolayer, acting as receptor layer of electrochemical sensors sensitive to sugars .
In this report, preliminary studies on the fabrication of electrochemical microsensors based on phenylboronic acid self-assembled monolayers of 4-mercaptophenyloboronic acid (MPBA) are presented. The efficiency of the formation of MPBA monolayers on the surface of back-side contact gold microelectrodes developed in silicon technology were studied using quartz crystal microbalance and chosen electrochemical techniques (cyclic voltammetry, impedance spectroscopy). Finally, the responses of the phenylboronic acid monolayer-modified microsensors towards selected bioanalytes (fluoride anion) have been reported.
 Takahashi S., Anzai J., Langmuir 21 (2005) 5102-5107
This work has been supported by the European Union in the framework of European Social Fund through the Warsaw University of Technology Development Programme, realized by Center for Advanced Studies and by National Center for Research and Development within a framework of LIDER programme (Nr LIDER/17/202/L-1/09/NCBiR/2010) and by Project MNS-DIAG Nr POIG.01.03.01-00-014/08-00.
Presentation: Poster at SMCBS'2011 International Workshop, by Martyna Jańczyk
See On-line Journal of SMCBS'2011 International Workshop
Submitted: 2011-09-07 11:34 Revised: 2011-09-07 11:34