Miniaturised reference electrodes for field-effect sensors compatible to silicon chip technology

Ag/AgCl reference electrodes without KCl-containing membrane ("quasi-reference" electrodes) have been fabricated by means of thick-film technique (screen-printing technique) and thin-film technique (electron-beam evaporation/chlorination or electron-beam evaporation/pulsed laser deposition). The different types of reference electrodes were characterised by means of scanning electron microscopy as a function of their preparation parameters. The potentials of the "quasi-reference" electrodes were measured versus a commercial Ag/AgCl reference electrode in 3 M KCl solution. The potential stability was up to 10 h (thin-film technique) and more than 1200 h (thick-film technique). In a next step, an additional KCl-containing agar membrane was deposited and different coatings have been used to protect the reference electrode from a fast leaching out of KCl. The leaching out could be improved from originally 3 h (by using no protective coating on top of the agar membrane) up to 50 days by using polyvinylchloride/nafion (PVC/N) or poly vinylchloride (PVC) as protective coating. Additionally, poly-(2-hydroxyethyl methacrylate) (pHEMA) has been studied as an alternative material for agar. (C) 2005 Elsevier Ltd. All rights reserved

An Innovative Method for Complete Microsensors Fabrication

AbstractA novel low-cost method of amperometric sensors’ fabrication based on thick-film technique on solid support and examples of their analytical applications are presented. The advantages of the fabrication method are flexibility in design and patterning of the deposited area applicable for both rapid prototyping of test samples and mass production. The developed graphite amperometric sensors were applied for quantitative detection of tricyclic antidepressants: imipramine and desipramine as well as DNA hybridization

Microfluidics Based System for Amperometric Determination of CRP

AbstractIn this paper, microfluidic based system for amperometric detection of CRP is described. The amperometric sensors were designed to operate in a microfluidic system for immunoenzymatic test (ELISA). The developed microfluidic system with integrated Pt amperometric sensors is suitable for determination of CRP in the lowest concentration range valuable for clinical diagnosis - 0.1mg/L to 1mg/L