FIA—See Flow-injection analysis

McKelvie, I. D. Cardwell, T. J. Cattrall, R. W. A Microconduit Flow Injection Analysis Demonstration Using a 35-mm Slide Projector, /. Chem. Educ. 1990, 67, 262-263. Directions are provided for constructing a small-scale FIA system that can be used to demonstrate the features of flow injection analysis. For another example see Grudpan, K. Thanasarn, T. Overhead Projector Injection Analysis, Anal. Proc. 1993, 30, 10-12. 

Flow injection analysis (F1A). In this technique, introduced by Ruzicka and Hansen, a small amount of sample is injected into a liquid flow (see Fig. 5.16), which apart from being automated is normally continuous, but can include the use of stopped-flow, merging zones extraction techniques in addition to FIA scanning and methods based on intermittent pumping89. The principles of FIA and the versions just mentioned will now be briefly discussed on the basis of the excellent review of Ruzicka and Hansen89 in order to understand the appli-cational possibilities of electrochemical detection in this technique. 

Routine analyses of large numbers of similar samples can readily be automated and the sample throughput considerably increased (sometimes up to about 200 samples per hour) by carrying out the analyses in a continuously flowing medium. At present there are two basic approaches to the problem, the older technique of continuous-flow analysis (CFA) introduced more than 25 years ago [145] and widely developed by the Technicon Company (Auto-Analyzer), and more recent flow-injection analysis (FIA for a recent literature review see [123]). For a brief comparative survey of the two methods see [148]. 

As a process analytical solution, these extrinsic reactive approaches necessitate an extrinsic optode (see later discussion), an on-line sample conditioning system or an at-Une solution such as a flow injection analysis (FIA) system or other autonomous solutions. Reaction kinetics, post analysis cleanup such as rejuvenating a substrate (optode, immobilized based immunoassays, etc.) among other complexities are additional considerations for these types real-time analysis methods. ... 

For more information on FIA see J. Ruzicka and E. H. Hansen, Flow Injectio Analysis, 2nd ed. New York Wiley. 1988 M. Valcarcel and M. D. Luque de Castro. Flow Injection Analysis Principles and Applications. Chichester, England Ellis Horwood, 1987 ... 

The difference between the closure restriction and the restriction of equal total concentration profiles in the flow injection analysis example (see Elaboration 2.1) is that the latter introduces a linear dependency between the columns of C, whereas the closure restriction does not. For a linear dependency between vectors a, b and c it must hold that kia + k2b + k3c = 0, for certain nonzero ki, X2, X3. This is the case for the equal total concentration profiles restrictions in the FIA example but not for the closure restriction. 

Currently, both chemical sensors and biosensors can be used at process lines in an at-line, FLA (flow injection analysis) mode. In FIA, a sample from the process stream is delivered to the sensor or measurement (see chapters 21 and 22 of this text). Currently, FIA is widely applied to process streams utilizing... 

Use of aerosols — A large number of applications require biosensors with a rapid response. Exaiiq)les include alarm systems, in which urgency is vital, and flow injection analysis (FIA), in which a rapid response can increase the sample throughput and reduce the cost of analysis. Biosensor response times are very dependent on the thickness of the active layer (see 4.2.1). Aerosol vaporization of dissolved compounds deposits films that are thin and homogeneous. 

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