|Search for content and authors|
Screen-printed Voltammetric Genosensors for Detection of Listeria Monocytogenes in Food
|Tomasz M. Oczkowski 2, Selim Achmatowicz 1, Marian Filipiak 2|
1. Institute of Electronic Materials Technology (ITME), Wólczyńska 133, Warszawa 01-919, Poland
The authors report here a preliminary evaluation of genosenor for detection of Listeria monocytogenes in food. Over the past decade, there has been an interest in electrochemical DNA biosensors for converting the hybridisation events into an analytical signal. Attractive features of this technology include simple approach, low-cost and single use sensor. Some of these approaches are based on screen-printed electrodes as electrochemical transducers. The purpose of the present study of DNA biosensors is to investigate the application of screen-printed electrochemical sensors for coupling with methods of amplification of the nucleic acid signal. A sequence of listeriosin O gene (hlyA) has been used as the probe. During the measurements, we used different kind of thick-film electrodes as disposable voltammetric sensors, based on various conventional and modified inks. The DNA probes were successfully adsorbed at controlled potential around 500 mV vs. Ag/AgCl on the surfaces of carbon electrodes. The DNA modified electrodes were electrochemically characterised with some of electroactive DNA binding complex Co(bpy)33+, daunomycin, ethidium bromide and methylene blue. The reaction on the electrode surface was monitored by cyclic and square-wave voltametry. The DNA hybridization has been observed in dependence of different concentration of oligonucleotides (in the range between 1 μg ml 1 - 20 μg ml-1). The hybridization reaction was performed using real samples of Listeria monocytogenes amplified by PCR. The new single-use genosensors, if combined with some of DNA amplification methods, allows determination of the genotype of the Listeria monocytogenes in shorter time than traditional phenotypic and biochemical testing.
Presentation: Keynote lecture at SMCBS 2003 Workshop, by Tomasz M. Oczkowski
See On-line Journal of SMCBS 2003 Workshop
Submitted: 2003-09-15 19:05 Revised: 2009-06-08 12:55