Flow-injection analysis field applications

In the context of FIA applications it is natural to predict that clinical chemistry and environmental pollution will be the two most appealing fields to this methodology. Flow injection analysis is also bound to bring significant changes in the future orientation of kinetic methods of analysis. 

D. Betteridge and B. Fields, The Application of pH Gradients in Flow-Injection Analysis. A Method for Simultaneous Determination of Binary Mixtures of Metal Ions in Solution. Anal. Chim. Acta, 132 (1981) 139. 

In the field of chemical analysis, biosensors have undergone rapid development over the last few years. This is due to the combination of new bioreceptors with the ever-growing number of transducers [1]. The characteristics of these biosensors have been improved, and their increased reliability has yielded new applications. Recently, a new technique of enzyme immobilization has been developed to obtain biosensors for the determination of enzyme substrates [2]. It is based on the enzyme adsorption followed by a crosslinking procedure. Therefore, a penicillin biosensor can be obtained and associated with a flow injection analysis (FIA) system for the on-line monitoring of penicillin during its production by fermentation [3-4]. This real-time monitoring of bioprocess would lead to optimization of the procedure, the yield of which could then be increased and the material cost decreased. 

Flow injection analysis (FIA) combined with biosensors offer new applications in the field of automated analysis and process control. Biosensors with rapid response time ensure high sample throughput, improve the sensitivity and decrease the cost of analysis. 

A more up-to-date application field of UV-vis spectrophotometry is flow injection analysis where the spectrophotometer is the generally used detector. In this technique, the sample and the reagent(s) are injected into a continuous, unsegmented flow produced by a pump. The reaction takes place in a temperature-controlled reaction coil, and the reaction product producing sharp peaks is measured in the detector. 

Wujian Miao illustrated a time line of various events in the development of ECL till 2002 (Fig. 1.3) [1]. As the time went on, this field attracted bulk of people to do research on ECL basic theory, emitters, mechanisms, applications, etc. Hence, advancements in the area of ECL increased exponentially over more than 45 years. After a long journey of almost half a century, ECL has now grown to be an incredibly potent analytical technique and been extensively used in many areas, such as criminology, forensic, environment, biomedical, biowarfare agent detection immunoassay [3], etc. This technique has also been effectively employed as a detector of flow injection analysis (FIA), high-performance liquid chromatography (HPLC), capillary electrophoresis (CE), and micro total analysis (pTAS) [13]. 

P.L.H.M. Cobben, R.J.M Egberink, J.G, Bomcr, EJ.R, Sudholler, P. Bergvcld, and D,N. Reinhoudt, Chemically modified ion-sensitive field-efifcct transistors application in flow injection analysis cells without polymeric encapsulation and wire bonding, Anal Chm. Acta, 248 (1991) 307-313. 

Llorent-Martinez, E. J., L. Molina-Garcia, R. Kwiatkowski, and A. Ruiz-Medina. 2013. Application of quantum dots in clinical and alimentary fields using multicom-mutated flow injection analysis. Talanta 109 203-208. 

Chapters on sample introduction and hyphenated sample treatment and ICP systems have also been further updated since the last edition. No doubt that chromatographic, electrophoresis, flow injection and field flow fraction separations have extended ICP-MS (and AES) measurements as the mainstay of elanental specia-tion measurements in biological and environmental fields. Without the combination of these separation techniques and ICP measurements, elemental speciation applications would be severely hampered... if not impossible (Chapter 18). The ability to measure P and S with high sensitivity has opened up new opportunities in proteomics, for example. Species-specific and unspecific isotopic dilution (ID-MS) has been critical in quantifying speciation analysis and revealing recovery errors (Chapter 13). Species-specific techniques have been applied to identify species transformations, resulting in the development of multi-species methods whereas, hyphenated species-unspecific ICP-ID-MS determinations of heteroatoms such as sulfur have become a common quantification technique in proteomics. 

Among polymer coated electrodes which have been the object of active investigations during this last decade, particular attention has been paid to the conductive polypyrrole films, obtained by electrooxidation of pyrrole in acetonitrile. Such electrodes have been used to study the electrochemical behaviours of the quinone-hydroquinone redox couple " and tetrathiafulvalene , The controlled release of ferrocyanide from polypyrrole by reduction of the polymer has been demonstrated . As an application, electroinactive anions can be determined using a polypyrrole modified electrochemical detector in flow-injection analysis. Pyrrole can be polymerized from aqueous solutions. Enlarging the modification field, the polymerization step may be preceded by a chemical reaction between pyrrole and another substrate . 

Results on the evaluation of the analytical and isotope ratio performance of ICP-TOF-MS measurements in steady-state signals"" " were discussed earlier in this chapter. However, the major application field of ICP-TOF-MS involves the multi-element and multiisotope analysis of rapid transient signals such as those commonly encountered in flow injection, 27,28,29-35 electrothermal vaporisation, laser ablation, "" capillary electrophoresis, (CE)" and chromatography.From the number of references related to the coupling of ICP-TOF-MS with a separation system, TOF-MS seems to be an attractive alternative to scanning-based systems for hyphenated speciation analysis. Leach et have recently reviewed the different hyphenated speciation systems that employ ICP-TOF-MS. 

Ryan R, Donegan S, Power J, Altria K (2010) Advances in the theory and application of MEEKC. Electrophoresis 31 755-767. doi 10.1002/elps.200900568 Yu L, Xu X, Huang L, Lin J, Chen G (2008) Microemulsion electrokinetic chromatography coupling with field amplified sample injection and electroosmotic flow suppressant for analysis of some quinolizidine alkaloids. J Chromatogr A 1198-1199 220-225. doi 10.1016/j.chroma2008.05.024... 

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