Flow-injection detector

Solvent Extraction Using a Polymer as Solvent with an Amperometric Flow-Injection Detector... 

J.J. Rippeth, T.D. Gibson, J.P. Hart, I.C. Hartley and G. Nelson, Flow-injection detector incorporating a screen-printed disposable amperomet-ric biosensor for monitoring organophosphorus pesticides, Analyst, 122 (1997) 1425-1429. 

L. Ilcheva and K. Cammann, A Simple, Selective and Sensitive Liquid-Chromatographic or Flow-Injection Detector for Chloro-Organic Compounds Based on Ion-Selective Electrodes. Fresenius Z. Anal. Chem., 325 (1986) 11. 

Rippeth J. J., Gibson T. D., Hart J. R, Hartley I. C., and Nelson G., Flow-injection detector, incorporating a screen-printed disposable amperometric biosensor for monitoring organophosphate pesticides. Analyst., 122, 1425-1429,1997. 

Eiceman, G.A. Garcia-Gonzalez, L. Wang, Y.-R Pittman, B. Burroughs, G.E., Ion mobility spectrometry as flow-injection detector and continuous flow monitor for aniline in hexane and water, Talanta 1992, 39,459—467. 

Flow injection analysis (FIA) was developed in the mid-1970s as a highly efficient technique for the automated analyses of samples. °> Unlike the centrifugal analyzer described earlier in this chapter, in which samples are simultaneously analyzed in batches of limited size, FIA allows for the rapid, sequential analysis of an unlimited number of samples. FIA is one member of a class of techniques called continuous-flow analyzers, in which samples are introduced sequentially at regular intervals into a liquid carrier stream that transports the samples to the detector. ... 

A graph showing the detector s response as a function of time in a flow injection analysis. 

Two examples of dual-channel manifolds for use In flow Injection analysis where R1 and R2 are reagent reservoirs P Is the pump S Is the sample I Is the Injector B Is a bypass loop W Is waste C Is the mixing and reaction coll and D Is the detector. 

A sensitive method for the flow injection analysis of Cu + is based on its ability to catalyze the oxidation of di-2-pyridyl ketone hydrazone (DPKH) by atmospheric oxygen. The product of the reaction is fluorescent and can be used to generate a signal when using a fluorometer as a detector. The yield of the reaction is at a maximum when the solution is made basic with NaOH. The fluorescence, however, is greatest in the presence of HCl. Sketch an FIA manifold that will be appropriate for this analysis. 

Enzyme linked electrochemical techniques can be carried out in two basic manners. In the first approach the enzyme is immobilized at the electrode. A second approach is to use a hydrodynamic technique, such as flow injection analysis (FIAEC) or liquid chromatography (LCEC), with the enzyme reaction being either off-line or on-line in a reactor prior to the amperometric detector. Hydrodynamic techniques provide a convenient and efficient method for transporting and mixing the substrate and enzyme, subsequent transport of product to the electrode, and rapid sample turnaround. The kinetics of the enzyme system can also be readily studied using hydrodynamic techniques. Immobilizing the enzyme at the electrode provides a simple system which is amenable to in vivo analysis. 

Column temperature Mobile phase Flow rate Detector Injection volume Retention time... 

Sample preparation, injection, calibration, and data collection, must be automated for process analysis. Methods used for flow injection analysis (FLA) are also useful for reliable sampling for process LC systems.1 Dynamic dilution is a technique that is used extensively in FIA.13 In this technique, sample from a loop or slot of a valve is diluted as it is transferred to a HPLC injection valve for analysis. As the diluted sample plug passes through the HPLC valve it is switched and the sample is injected onto the HPLC column for separation. The sample transfer time typically is determined with a refractive index detector and valve switching, which can be controlled by an integrator or computer. The transfer time is very reproducible. Calibration is typically done by external standardization using normalization by response factor. Internal standardization has also been used. To detect upsets or for process optimization, absolute numbers are not always needed. An alternative to... 

The 1/16" x 0.02" i.d. transfer line also functioned as a sample dilution device in other applications, a stainless steel column packed with glass beads has been found to be useful for dilution. This simple dynamic dilution technique has been used extensively in flow injection analysis.3 A refractive index detector is typically used to measure the sample transfer time. As shown in Figure 4, approximately 5 minutes is required to transfer the sample plug to the Rheodyne valve. As the apex of the sample band passes though the Rheodyne valve, the valve is activated and 1 pi injected onto the liquid chromatographic column. The sample transfer time was checked periodically over 1 year of operation and found to be stable. 

Flow injection Chemical ionisation (Cl) Quadrupole ion trap (QITMS) Diode array detector... 

Another interesting development, in which continuous flow was combined with discrete sample titration, is continuous flow titration by means of flow injection analysis (FIA) according to Ruzicka and co-workers70. Fig. 5.16 shows a schematic diagram of flow injection titration, where P is a peristaltic pump, S the sample injected into the carrier stream of diluent (flow-rate fA), G a gradient chamber of volume V, R the coil into which the titrant is pumped (flow-rate fB), D the detector and W waste. 

Numata, M., Funazaki, N., Ito, S., Asano, Y., and Yano, Y., Flow injection analysis for hypoxanthine in meat with dissolved oxygen detector and enzyme reactor, Talanta, 43,2053,1996. 

Fast Fourier Transform Flow Injection Analysis Field Ion Atom Probe Flame-Ionization Detector Field Ion Microscopy... 

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