Application Of Flow Injection Analysis Research Articles

Flow injection analysis: a novel tool for plasma spectroscopy

The principles of flow injection analysis (FIA) are briefly described, along with some advantages for analytical measurement. The applications of FIA to ICP for trace and multielement analysis are reviewed. Topics discussed include the sampling process and ways of improving the efficiency of sample introduction, multicomponent analysis, speciation, standard addition, hydride generation, preconcentration techniques and conversion methods. Methods used in atomic absorption spectrometry are mentioned as potential applications in ICP, including use of nonaqueous solvents and gas carriers.

Application of flow injection analysis to water pollution studies

The application of flow injection analysis and reverse flow injection analysis under field conditions could completely change our present techniques of water pollution monitoring.

Application of flow injection techniques for the analysis of inorganic anions

A survey of applications of flow injection analysis for the analysis of inorganic anions is given in form of a table. The turbidimetric determination of sulphate is improved by the intermittent addition of a wash solution via a separate pump. A comparison of results for the determination of sulphate in surface waters using the barium-methylthymol blue method and ion-chromatography shows good agreement. For the determination of sulphite a gas-diffusion technique is used. The method allows 90 injections/h and shows good reproducibility, 1% r.s.d. for consecutive injections of standards at the 10 mg/l SO2-level. As the sample line is physically separated from the detection line, the method is insensitive to matrix effects from coloured or turbid samples. Results for the determination of free and total sulphite in wine, beer and fruit juices are given.

Application of automated flow injection analysis (FIA) to dissolution studies

The application of FIA to dissolution studies is described. Propantheline bromide, salicylamide and sulfamethizole were chosen as model drugs to investigate the utility of FIA method for dissolution studies. In each case the FIA system with the appropriate chemistry manifold was coupled with the rotating basket apparatus, A fully automated monitoring of dissolution rates was achieved. A complete dissolution profile in tabulated form is provided by the computer of the system at the end of the experiment. Automation of any type of solid dosage forms agitation technique can be easily acquired by adapting a FIA system.

Ion chromatography of Mg, Ca, Sr and Ba ions using a metallic copper electrode as a potentiometric detector

The determination of inorganic cations by high-performance liquid chromatography (HPLC) has received increased attention over recent years and when compared with most conventional spectroscopic methods, HPLC offers the considerable advantage of allowing a number of cations to be determined in a single run. This approach has been successfully used for the determination of alkali metal and ammonium ions, alkaline earth metal ions, transition metal ions and lanthanides. These methods have been based on ion-exchange or ion-pairing separation techniques, coupled with conductivity, coulometric or spectrophotometric detection. In the latter case, detection was accomplished by a post-column reaction system wherein coloured metal complexes were formed. An important disadvantage of such a post-column reaction detector is the band broadening which inevitably results in the mixing coil. We have previously described a potentiometric HPLC detector based on an active copper surface as the sensing electrode. This device was originally applied to the direct detection of copper complexing ligands such as amino acids, but we also recently reported its application in flow-injection analysis to the indirect detection of cations in a suitable carrier. The aim of this communication is to indicate the utility of potentiometric detection in cation chromatography as an alternative to presently used detection methods.

Spectrophotometric determination of traces of iron with 2-(3,5-dibromo-2-pyridylazo)-5-[ N-ethyl- N-(3-sulfopropyl)amino]phenol and its application in flow injection analysis

2-(3,5-Dibromo-2-pyridylazo)-5-[ N-ethyl- N-(3-sulfopropyl)amino]phenol reacts with iron(II) to form a water-soluble chelate, which gives two absorption maxima at 568 nm (ϵ = 88000 l mol −1 cm −1) and 748 nm (ϵ = 39000 l mol −1 cm−1). A spectrophotometric determination of 1–35 μg of iron is described. Interferences from other metals are eliminated with N-(dithiocarboxy)sarcosine and EDTA; Cu (15 or 30 μg), Ni (3 or 60 μg), Zn (30 or 130 μg) and Co (20 or 150 μg) do not interfere when the absorbances are measured at 570 nm or 750 nm, respectively. For the flow-injection procedure, the calibration graph is linear for 20–440 μg l −1 iron at 750 nm. Total iron in potable waters can be determined after some preliminary treatment. The sample rate is 30 h −1.