Technicon Autoanalyzer

Partial) dialysis in flow analysis. The sample solution flows along one side of the membrane, while the analyser solution passing (often in counter-current) on the other side takes up the diffused components from the sample. A dynamic equilibrium is reached (under steady-state conditions) in the leaving analyser solution, which is then analysed and from the result of which the analyte content can be derived via calibration with standard solutions treated in exactly the same way. This is a common procedure, e.g., in Technicon AutoAnalyzers, and has also been applied in haemoanalysis by Ammann et al.154 as described above. 

Flow injection analysis has been adapted to automatic air-segmented continuous flow systems, e.g., the Technicon AutoAnalyzer system. Several reducing... 

The Adamski [13] procedure is semiautomated. It gives an accuracy of 8.1% and a precision of 8.2% for seawater samples spiked with 3-35 p,g/l organic nitrogen. This procedure is based on the indophenol blue method and was employed using a Technicon AutoAnalyzer II system with the appropriate accessories. Various workers have described automated procedures for determination of low levels of organic nitrogen in seawater [15,16]. 

An automated turbidimetric procedure using a Technicon Autoanalyzer has also been described (See Section 6.5). 

Organic phosphorus is determined by the difference in phosphorus content of the 1M hydrochloric acid extract measured before and after ignition of the dry sediments at 550°C. In all instances the orthophosphate is determined by using standard Technicon AutoAnalyzer II techniques. Silica does not interfere. 

Continuous segmented methods avoid carry-over by use of air bubbles establishing physical separations (segments) along the continuous flowing stream. These methods were invented by Skeggs [1] and formed the basis of the Technicon AutoAnalyzer. They are now also implemented on Skalar assembhes. Samples are introduced sequentially by aspiration with a moving articulated pipette. 

This type of analyser is usually modular in nature and consists of a series of elements (apparatus, instruments) coupled on-line to one another. Figure 2.13 shows the essential components of a straightforward Technicon AutoAnalyzer, namely ... 

However, a commercial instrument must have a broad appeal and the chemistry regime based on acid/sodium tetrahydroborate offers the most attractive approach. It has a rapid reaction, caters for all of the hydride-forming elements and can be very easily automated. To optimize the procedures, the use of standard Technicon AutoAnalyzer methodologies, i.e. matching blanks, standards and sample matrices, overcomes the difficulties due to matrix interference. Also, the detection levels achieved by a well-designed system allow the samples to be diluted, avoiding any problems still present due to matrix interference. Stockwell [9] has described a system which achieves detection levels that are an order of magnitude better than other systems. 

There is usually no problem of access to basic laboratory instruments and associated glassware, however, the only means of handling large numbers of tests is to apply some form of automation. An added advantage is that it improves the analytical precision and reproducibility. The most suitable technique has been based on the segmented continuous-flow principle invented by Skeggs (1957), and which was first marketed as the Technicon AutoAnalyzer. The system consists of a number of modules powered from a stabilized 110 V supply, and a typical layout is shown in Fig. 1.1. 

Armstrong, F.A.J., Sterns, C.R. and Strickland, J.D.H. (1967) The measurement of upwelling and subsequent biological processes by means of the Technicon AutoAnalyzer and associated equipment. Deep-Sea Research 14, 381-389. 

Biogenic silicon (BSI) was determined, with minor modifications, by the method of DeMaster (17). As adapted, the technique involved time-course leaching of <20-mg samples of particulate matter in 30 mL of 1.0% Na2C03 in a water bath at 85 °C. Silica in leachates was quantified either colorimetrically (Technicon autoanalyzer procedure) or by nitrous oxide flame atomic absorption. A high-temperature catalytic-combustion technique (Perkin Elmer 240C) was used for particulate organic carbon determinations. Particulate inorganic (carbonate) carbon was measured on the same instrument by CO 2 evolution after treatment of the particles with phosphoric acid. 

The apparatus used for the analysis is a continuous flow automated analytical instrument such as Technicon Autoanalyzer. Follow the manufacturer s instructions to set up the manifold and for general operation. 

The analysis is performed using a continuous flow analytical instrument such as Technicon Autoanalyzer or equivalent. The sample is distilled and the distillate, free of interference, is reacted with alizarin fluorine blue [C14H704 CH2N(CH2 COOH)2]-lanthanum reagent to form a blue complex. The absorbance is measured at 620 nm. Standard fluoride solutions are prepared in the range from 0.1 to 2.0 mg F /L using the stock fluoride solution. 

Column Chromatography. Amino acids were determined in hydrochloric acid hydrolyzates with a 150-cm. column of Amberlite IR-120 (17) using the Technicon AutoAnalyzer. Quantitative measurements were made colorimetrically (17). An alternate method of analysis made use of a 133-cm. column of Technicon chromobead resin and a modification of the sulfur system described by Piez and Morris (14). Although this method gave excellent separation of all classes of amino acids, its value was limited by the failure to separate cystine from glucosamine. Cystine values, therefore, were determined from the IR-120 chromatograms alone. 

Oudot, C., and Montel, Y. (1988). A high sensitivity method for the determination of nanomolar concentrations of nitrate and nitrite in seawater with a Technicon autoanalyzer II. Mar. Chem. 24, 239-252. 

Reactants are pumped from storage, then heated and injected into a mixing chamber (black flow lines). Sample is added to the mixing chamber, the mixture is injected into the flow cell, and the formazan production is monitored every 15 s for 3.5 min. The mixture is flushed, the system is rinsed, and the cycle begins again. The hatched regions are maintained at surface seawater temperatures. The four solenoid valves function most of the time in normally open (NO) or normally closed (NC) positions. A Technicon Autoanalyzer pump and a Bausch and Lomb Spectronic 88 spectrophotometer were used. 

U.se of the Technicon AutoAnalyzer in Seawater Nutrient Analyses Ref. No. 71-72, Oregon State Uniy. Corvallis, Oreg., 1971 49 pp. 

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