Screen-printing technologies

Scanning electron microscopy, 125 Scanning probe microscopy, 46 Scamring tunneling microscopy, 46 Screen-printing technology, 111, 177, 178, 195... 

Occasionally, we prepare a different type of electrode - we screen-print them. With modem screen-printing technology, a complicated arrangement of precisely arranged and well-defined electrodes can be prepared on the solid substrate of choice. In essence, these electrodes are simply dots of conductive material, with suitable electrical contacts to ensure that each can be addressed correctly. As an example, each electrode can be connected to a separate channel of a frequency analyser or potentiostat. In this way, a great many analyses can be performed simultaneously. 

The possible use of graphite-epoxy material by screen-printing technology opens the possibility of mass production of disposable sensors for heavy-metal analysis using stripping techniques. The utilization of these sensors for an extensive application in real heavy-metal samples is underway in our laboratories. 

Electrochemical sensors and biosensors offer the achievable opportunity of simplifying the analyses of complex matrices, outside of the laboratory, by suitable modification of appropriate electrode materials [1-5]. One of the most attractive methods for the fabrication of such devices involves the use of screen-printing technology. This allows the (bio)sensors to be manufactured in a wide range of geometries at low cost, particularly when carbon is used therefore, this allows the devices to become disposable [1,2]. A typical screen-printed electrode design commonly used in our laboratories for prototype investigations is shown in Fig. 23.1. 

Biosensors for the determination of blood glucose have enjoyed widespread commercial success since the introduction of the pen-sized 30 s blood glucose meter [10]. However, researchers have continued to devise novel approaches in the development of amperometric biosensors based on screen-printing technology Table 23.1 summarises some examples of these approaches together with their performance characteristics. 

J.P. Hart, A.K. Abass, K.C. Honeychurch, R.M. Pemberton, S.L. Ryan and R. Wedge, Sensors/biosensors, based on screen-printing technology for biomedical applications, Indian J. Chem., Sect. A, 42 (2003) 709-718. 

Electrochemical analytical methods, particularly polarography and voltammetry rise in the 1960s was caused by the demand in trace analysis and new technique of preliminary electrochemical concentration of the determined substance on the electrode surface [1,2]. The reason for the new renaissance is the use of screen-printed technologies, which resulted in creation of new electrodes so cheap that they can be easily disposed and there is no need of regenerating the solid electrode surface [3]. 

Lamination (used by Patel et al. [18] above) is a fabrication technique that could be considered more widely by researchers in laboratories as an adjunct to screen-printing, particularly for deposition of outer diffusion-limiting membranes. Sensors can be constructed entirely by screen-printing technology [16], but it is difficult to maintain control over membrane thickness, porosity, etc. Deposition of pre-cast membranes by lamination may be a way of controlling these parameters more precisely. 

Most biosensors based on AChE have the enzymes immobilized on the surface of the sensor. The inhibition reaction being irreversible, the membrane with immobilized enzyme has to be replaced after several measurements or the biosensor can be use for only one determination. Due to this fact, the researchers tried to realize pesticide biosensors with a renewable surface or disposable biosensors based on screen-printed electrodes (SPE). The screen-printing technology provides a simple, fast and inexpensive method for mass production of disposable biosensors for different biomolecules starting with glucose, lactate and finishing with environmental contaminants as pesticides (Kulys et al., 1991) and herbicides (Skladal, 1992). 

In this example, the sensing layer, in the form of a thick porous film, is deposited by applying screen-printing technology onto a planar alumina substrate equipped with interdigitated Pt electrodes on its front, for the... 

Riviere, B., Viricelle, J. P. and Pijolat, C. (2003) Development of tin oxide material by screen-printing technology for micro-machined gas sensors. Sensors and Actuators B Chemical 93,531-7. 

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