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CP-93,393 is a drug candidate at Pfizer. Flow-injection analysis-mass spectrometry (FIA-MS) was used to monitor reaction completion for CP-93,393 reaction mixtures. FIA-MS provides essentially instantaneous results, is relatively simple to operate, and is a universal system that can be used to monitor any reaction as long as the product has a molecular weight that differs from the molecular weights...
Speciation of elements in natural matrices, especially of trace metals, is one of the predominant development trends of modern inorganic analysis. The main part of the conventional speciation procedures is a suitable combination of separation and chemical conversion steps, for which the most appropriate methodology seems to be the use of flow-injection. A shorter time of performance of these operations...
The specificity of enzymes is often not sufficient to simultaneously determine two parent substrates in a given matrix. Approaches to enhance the selectivity by applying the principle of an array arrangement to flow-injection analysis (FIA) systems based on several immobilized isoenzymes are successful. Immobilized enzymes and detectors in FIA systems often suffer from interferences from impurities...
An automated flow-injection method for determination of primary aromatic amines based on the Bratton-Marshall reaction is described. This method is used for analysis quality control of three different X-ray contrast media (Omnipaque ® , Imagopaque ® and Visipaque ® which are viscous solutions. In flow-injection analysis, such samples cause refractive index effects and low....
Addition of diethylenetriaminepentaacetic acid (DTPA) to the fluorescent binary complex of thorium and 8-hydroxyquinoline-5-sulfonic acid (HQS) forms the Th-DTPA-HQS fluorescent ternary complex. The formation of this ternary complex enhances the selectivity for the determination of thorium. Excesses of DTPA and HQS are used as reagents in flow-injection analysis to detect thorium. The excess DTPA...
Chemical analysis of surface active species (surfactants) is of interest for many applications, such as in process monitoring, biomedical applications, environmental monitoring and surface science investigations. Recently, we reported a dynamic surface tension detector (DSTD) based upon optically probing the size of a repeating drop resulting from constant flow of an aqueous solvent out of the end...
A lot of modern analytical strategies for exploiting chemistries have been developed by using flow-injection analysis. However, even after 20 years of flow-injection evolution, there still are new quantitative procedures being established using old qualitative assays. The formation of Prussian Blue is a classical test to detect Fe 2+ using hexacyanoferrate(III) as a precipitating reagent....
A flow-injection analytical method for the determination of hydrochlorothiazide is presented. The method is based on the chemiluminescence reaction of hydrochlorothiazide with cerium(IV) in sulphuric acid, sensitized by the fluorescent dye rhodamine 6G. The proposed procedure allows quantitation of hydrochlorothiazide in the concentration range of 0.33–130 μmol l −1 with a detection limit...
A flow-injection configuration based on a dual-phase gas-permeation system from a liquid donor to a gas acceptor stream with a thermistor flow-through detector is proposed for the direct analysis of the gas in the acceptor. This system was applied for the determination of carbon dioxide (in the form of carbonate) using the following chemical reaction: CO 2 (g)+2NH 3 (g)+H 2 ...
A novel chemiluminescence (CL) system for ammonium ion combined with flow-injection analysis is presented in this paper. It is based on the CL reaction between luminol, immobilized electrostatically on an anion-exchange column, and chlorine electrochemically generated on-line via a platinum electrode from hydrochloric acid in a coulometric cell. Ammonium ion reacts with chlorine and decreases the...
With the intention of combining partition chromatography and membrane techniques, we succeeded in developing the chromatomembrane cell which has proved to be reliable as an extraction and preconcentration manifold in flow injection analysis. With this technique, two immiscible phases can be induced to flow independently through a block of biporous (macro and micro) PTFE in order to promote analyte...
An automated flow-injection system combining a pyruvate oxidase reaction and chemiluminescence for the detection of phosphate ion in river water has been developed. In this research, we used pyruvate oxidase G (PyrOxG), from Aerococcus viridans, immobilizing it on N-hydroxysuccinicacidimido beads without a cross-linker. In this sensor system, which was constructed as a trial system of desktop type,...
An automated system with a C 18 bonded silica gel packed minicolumn is proposed for spectrophotometric detection of arsenic using flow-injection hydride generation following sorbent extraction preconcentration. Complexes formed between arsenic(III) and ammonium diethyl dithiophosphate (ADDP) are retained on a C 18 sorbent. The eluted As-DDP complexes are merged with a 1.5%...
Flow-injection solid-phase spectrophotometry is applied for sequential determination of nickel and zinc, exploiting their different sorption rates on 1-(2-thiazolylazo)-2-naphthol (TAN) immobilized on C 18 -bonded silica. The Zn(II) sorption rate on the solid support is constant for flow rates ranging from 0.70 to 2.2 ml min -1 , but for Ni(II) the sorption rate decreases...
An enzymatically modified ammonium ion-selective electrode has been applied for the determination of urea in spent dialysate. The biosensor has been used in a simple flow-injection analysis (FIA) system. The system enables one to perform over 25 dialysate urea nitrogen (DUN) determinations per hour. The interferences from other components of posthemodialysis fluid were eliminated by simultaneous measurements...
The bovine serum album binding of streptomycin sulfate was studied in vitro using the technique of microdialysis combined with flow-injection analysis-chemiluminescence detection. The principle of the determination of streptomycin sulfate is that it increases the radiation emitted during the chemiluminescence oxidation of luminol by potassium hexacyanoferrate (III) in sodium hydroxide medium. The...
The concentration profile of chemical species pumped through a tubular system of 0.5-mm inner diameter is found to be trapezial shaped, as described theoretically by including the spatial resolution of the instrument, friction and diffusion. By applying the theory, which is based on the concept of segment flow, to experiments, it is shown that an injected segment of solute is diluted predominantly...
A simple and sensitive flow-injection chemiluminescence (CL) system for automated dissolution testing is described and evaluated for monitoring of dissolution profiles of isoniazid tablets. The undissolved suspended particles in the dissolved solution were eliminated via on-line filter. The novel CL system of KIO 4 -isoniazid was also investigated. The sampling frequency of the system was...
A gold(I) organic complex in the perchlorate form was incorporated in plasticized poly(vinyl chloride) (PVC) membranes and the potentiometric response towards perchlorate (primary ion) and permanganate (interfering ion) was studied. Membranes with 2:1 and 1:2 (w/w) plasticizer to PVC ratio were selected for the determination of primary and interfering ions, respectively. In the selected flow injection...
A flow-injection method for the determination of serine using a mini-column containing immobilized serine dehydratase isolated and purified from rat liver is described. Ammonia produced from the enzymatic reaction is coupled with hypochlorite and phenol in an alkaline medium yields a blue product due to the indophenol anion formation, which is the basis of a spectrophotometric detection at 640 nm...
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