Flow Injection Tutorial

Our research on flow injection techniques begun in early 80's at the Department of Analytical Chemistry Faculty of Pharmacy, Charles University, Czech Republic. Our Department is situated in Hradec Kralove, a charming historical city, north east of Prague. The Department, founded in 1969, had from the start a robust research program in synthesis and analytical application of organic ligands, in electrophoresis, in paper chromatography, in electrochemical and in spectrophotometric instrumentation. It was therefore natural to adapt a new technique that was designed to automate reagent based assays, also because we had a previous experience in spectrophotometric studies of complex-formation equilibria (1).

While academic research in chemistry, and analytical chemistry, had a long and outstanding history in Czechoslovakia (J. Heyrovsky obtained Nobel Prize for discovery of Polarography in 1959), the work before 1989, east of Iron Curtain, was difficult for two reasons. Instrumentation, chemicals and scientific literature from West were very difficult to obtain, through a lengthy process, which more often than not failed due to lack of foreign currency. The other reason was political, absurdly, quoting publications from Western sources was discouraged, and when prof. J. Zyka offered to translate book "Flow Injection Analysis" by J. Ruzicka and E.H.Hansen (2) it was forbidden (as it was routinely done for work of many others, who emigrated from then communist controlled Czechoslovakia). And we since did not have foreign currency for buying the English version - it worked like a censorship.

We therefore decided to go ahead by available means, while focusing on real life applications, which required automation of sequential repetitive operations, such as analytical assays. Also from our previous experience with spectrophotometric flow through measurement, it was only a small step to construct FIA setup, which was far simpler than air segmented flow systems. The biggest challenge was construction of a device, which would allow injection of precise volumes of sample into the flowing stream. After many trials we came up with a design that, when fabricated in our Faculty workshop, allowed precise injections within the range of 20 to 200 microliters. This manually operated valve was later improved to allow injection of two solutions simultaneously. Next, we designed and fabricated peristaltic pumps, mixing connectors and reaction coils (using 0.5mm I.D. tubing), thus completing FIA analyzer (Fig. 1), that became recognized as significant advance of then existing technology (3) and became a model for industrial production (4). Our next goal was to disseminate application of FIA technique in Czech research and industrial laboratories, through training of students and visitors in our laboratory (5), and by instrument demonstration on research gatherings (Fig. 2). Soon there was a need to produce the instrument serially, and we were lucky to find an unusual candidate. It was the Unified Agricultural Cooperative "1st of May" in the village of Pouchov, near Hradec Kralove (6). This FIA 20 Analyzer, furnished with SPEKOL photometer (manufactured in East Germany), and chart recorder, became a milestone in acceptance of flow injection technique in our country, as it became widely used in agrochemical and industrial laboratories. During following years (1985 to 1990) we developed a number of reagent-based assay protocols for chloride, ammonia, nitrite, nitrate, but also for phenols, boron and molybdenum in soils, water and plant materials. For clinical assays, FIA protocols for calcium, protein and other analytes became available.

Our students at all levels used FIA instrumentation, and their graduate work culminated in a number of PhD. thesis (7-11). In our course Instrumental Analysis for pregraduate students, one exercise was FIA assay of nitrite and nitrate in water collected from wells in surrounding countryside.

After the fall of the Wall in 1989, it became possible for us to travel abroad, and to present our research on international meetings, and in international journals (12-27). Gradually our work became internationally recognized, culminating at the 10th International Conference on Flow Injection Analysis which we organized in Prague in 1999 (Fig.3).

Presently there are at our Department ten faculty members, six research associates, and twelve graduate students, not only from Czech Republic, but also from Germany, Spain, Thailand and Russia. In recent years vising scientists came from Slovakia, Ukraine, Russia, Portugal, Spain, Argentina, Brazil, Japan, Australia and Jarda Ruzicka as Fulbright Professor from USA.