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The development of insulator-based dielectrophoresis chromatography is proposed here as a novel hybrid technique that capitalizes on the simplicity of insulator-based dielectrophoresis (iDEP) and the well-known chromatographic theory. Chromatographic parameters are employed to characterize dielectrophoretic separation of particles with particles being eluted from the system as enriched particle peaks. By varying the characteristics of the insulating posts, it was possible to manipulate the interactions of the particles with the insulating post array which acted as the stationary phase. The present work studied how the characteristics of the particles affected the particle retention. Different types of particles have distinct interactions with the post array; these interactions depend on particle properties (size, electrical charge, and polarizability). This work includes mathematical modeling with COMSOL and extensive experimentation. Particles ranging from 1 to 10 μm in diameter were tested for retention time and eluted as peaks in the iDEP chromatography devices. Separation results were reported in the form of dielectropherograms including the estimation of retention time (tR), separation efficiency (N/meter), and separation resolution (Rs). Two full separations were demonstrated: a separation by charge between two types of particles of similar size (~ 10 μm) with different electrical surface charges and a separation by size between 2- and 5-μm particles with similar surface charge (difference in ζP of 4 mV). The achieved separation resolutions were Rs = 1.8 and Rs = 3.5, respectively. This is the first study on DEP chromatography to assess performance in terms of resolution and separation efficiency, demonstrating the unique potential of iDEP chromatography. [ABSTRACT FROM AUTHOR]

• Recent advances in paper/thread-based zone and capillary electrophoresis techniques. • Various sample pretreatment methods using electrophoresis on wicking substrates. • Review of unmodified and modified microfluidic paper/threat -based chromatography. • Application of paper/threat -based chromatography in blood separation. Paper and thread are widely used as the substrates for fabricating low-cost, disposable, and portable microfluidic analytical devices used in clinical, environmental, and food safety monitoring. Concerning separation methods including chromatography and electrophoresis, these substrates provide unique platforms for developing portable devices. This review focuses on summarizing recent research on the miniaturization of the separation techniques using paper and thread. Preconcentration, purification, desalination, and separation of various analytes are achievable using electrophoresis and chromatography methods integrated with modified or unmodified paper/thread wicking channels. A variety of 2D and 3D designs of paper/thread platforms for zone electrophoresis, capillary electrophoresis, and modified/unmodified chromatography are discussed with emphasis on their limitation and improvements. The current progress in the signal amplification strategies such as isoelectric focusing, isotachophoresis, ion concentration polarization, isoelectric focusing, and stacking methods in paper-based devices are reviewed. Different strategies for chromatographic separations based on paper/thread will be explained. The separation of target species from complex samples and their determination by integration with other analytical methods like spectroscopy and electrochemistry are well-listed. Furthermore, the innovations for plasma and cell separation from blood as an important human biofluid are presented, and the related paper/thread modification methods are explored. [ABSTRACT FROM AUTHOR]

In current scenario the field of questioned documents is not only dealing with examination of handwriting but also with the comparison and analysis of writing ink. Over the past years, questioned document examiners have struggled with various documents, their examination and identification with respect to inks. Examination of ink serves as an important key in establishing the authenticity of questioned documents. This article focuses on various techniques which have been used in recent years for scientific examination of ink. The techniques included are categorized on the basis of four broad categories i.e. chromatography, electrophoresis, spectroscopy and miscellaneous. This article will help examiners to select the appropriate method and conduct examination and identification of ink with the best suited method. [ABSTRACT FROM AUTHOR]

Human health has been revolutionary improved relying on the progressive development in the pharmaceutical products. This can be achieved only if these products are assured purity and ingredients. Consequently, many analytical techniques were developed to confer this purpose. In the same context, the pharmaceutical products can be contaminated through different steps during their processing rendering these pharmaceuticals gain the probability of being hazardous to be consumed. Hence, these pharmaceutical products should be qualified and quantified. Accordingly, the analytical techniques possess a significant role in the pharmaceutical drug determination. This review highlights the role of the analytical instrumentation and the analytical methods in assessing the quality of the drugs. In this study, the authors point out different technical drug analyses encompasses spectroscopy, titrimetry, electrophoresis, chromatography, and electrochemical analyses utilized in the analysis of pharmaceutical products. [ABSTRACT FROM AUTHOR]

A comprehensive review with 337 references for the analysis of some selected 4-quinolone drugs belonging to the first and second generations since 2006 up till now is presented. This group includes nalidixic acid, oxolinic acid, piromidic acid, pipemidic acid and rosoxacin from the first generation and enoxacin, fleroxacin, nadifloxacin, pefloxacin and rufloxacin from the second generation. The review covers most of the methods described for the analysis of these drugs, either per se, in dosage forms, biological fluids, environmental samples, cosmetics, animal tissues and feed-premix samples. [ABSTRACT FROM AUTHOR]

Described as intrinsically powerful building blocks for two-dimensional separations by Giddings [Anal. Chem., 56 (1984) 1258A–1270A], the coupling of chromatography and electrophoresis has been proven to enhance the resolution of a wide array of molecules in complex biological, environmental and food samples. This review provides a comprehensive overview of multidimensional chromato-electrophoretic (LC - E) and electrophero-chromatographic (E - LC) separation systems from inception to the most recent published examples. LC separation modes include reversed phase, ion exchange, and size exclusion. Electromigration separation modes include capillary, microchip or free flow electrophoresis; micellar electrokinetic chromatography; electrochromatography; and isoelectric focusing. The advantages and disadvantages of various non-gel based off-line and on-line hyphenation technologies of LC - E and E - LC are discussed, with conditions and system characteristics also provided. [ABSTRACT FROM AUTHOR]

Protein recovery from gel electrophoresis plays a significant role in functional genomics and proteomics. To assist in this, a simple, cost-effective, and efficient apparatus for electroelution of proteins has been designed. The performance of the apparatus was demonstrated using the proteins bovine serum albumin (BSA), phosphorylase, ovalbumin, pepsin, and trypsinogen. In all the cases the yield of elution was found to be consistently greater than 85% and the proteins could be eluted without degradation in less than 15 min. The utility of this method can be extended to protein elution from denatured and native polyacrylamide gels, DNA purification from agarose gels, and oligomeric primers purification from polyacrylamide gels. In addition to this, the method offers an effortless purification and characterization of microbial extracellular proteins. The eluted proteins can be directly used in N-terminal amino acid sequencing, and in amino acid and proteomics analyses. [ABSTRACT FROM PUBLISHER]

Soluble nanoscale lipid bilayers, termed nanodiscs, are widely used in science for studying the membrane-anchored and integral membrane protein complexes under defined experimental conditions. Although their formation occurs by a self-assembly process, nanodisc purification and the verification of proper reconstitution are still major challenges during the sample preparation. This review gives an overview of the methods used for purifying and analyzing nanodiscs and nanodisc-reconstituted membrane proteins, with an emphasis on the chromatographic and electrophoretic approaches. [ABSTRACT FROM AUTHOR]

Peroxidase (EC 1.11.1.7; donor: hydrogen peroxide oxidoreductase) is an oxidoreductase enzyme found in many fruits and vegetables. This enzyme was purified from sweet gourd (Cucurbita moschata Lam. Poiret) by ammonium sulphate precipitation and CM-Sephadex ion-exchange chromatography. Furthermore, optimum pH, optimum temperature, optimum ionic strength, stable pH, and stable temperature conditions were determined as 7.2, 50°C, 0.4 M, 8.0, and 40°C, respectively. The molecular weight (MW) of the enzyme was estimated to be 85 kDa by SDS-PAGE method. The values of Km and Vmax were calculated from the Lineweaver-Burk graph for guaiacol/H2O2 substrate patterns. [ABSTRACT FROM AUTHOR]

The use of a new class of high-molecular-weight substances, dendritic polymers (dendrimers and hyperbranched polymers), as components of chromatographic and electrophoretic systems is discussed; the effect of their introduction into a background electrolyte or an eluent on the separation efficiency and selectivity of organic compounds of different classes is considered. [ABSTRACT FROM AUTHOR]

Nanoparticle-based material is a revolutionary scientific and engineering venture that will invariably impact the existing analytical separation and preconcentration for a variety of analytes. Nanoparticles can be regarded as a hybrid between small molecule and bulk material. A material on the nanoscale produces considerable changes on various properties, making them size- and shape-dependent. Gold nanoparticles (Au NPs), one of the wide variety of core materials available, coupled with tunable surface properties in the form of inorganic or inorganic-organic hybrid have been reported as an excellent platform for a broad range of analytical methods. This review aims to introduce the basic principles, examples, and descriptions of methods for the characterization of Au NPs by using chromatography, electrophoresis, and self-assembly strategies for separation science. Some of the latest important applications of using Au NPs as stationary phases toward open-tubular capillary electrochromatography, gas chromatography, and liquid chromatography as well as roles of run buffer additive to enhance separation and preconcentration in the field of chromatographic, electrophoretic and in chip-based systems are reviewed. Additionally, we review Au NPs-assisted state-of-the-art techniques involving the use of micellar electrokinetic chromatography, an online diode array detector, solid-phase extraction, and mass spectrometry for the preconcentration of some chemical compounds and biomolecules. [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

Adulterated food can be defined as food incompatible with the declaration of the seller. In the case of meat and meat articles, adulterations refer not only to the replacement of ingredients but also to inappropriate information concerning the origin of raw materials. Methods aiming at investigating meat and meat product authenticity may be based either on the analysis of protein composition or on the analysis of nucleic acids. At the present time, meat and meat product authenticity investigations based on protein analysis employ electrophoretic, enzymic, and chromatographic methods, sometimes supported by the mass spectrometry technique. On the other hand, species identification is often based on polymerase chain reaction (PCR). Biochips present a promising technology. [ABSTRACT FROM AUTHOR]

Surface charge, molecular weight, and folding state are known to influence protein chromatographic behavior onto ion-exchangers. Experimentally, information related to such factors can be gathered via two-dimensional electrophoretic (2-DE) methods. The separation behavior depicted by the insect cultured-cells proteome, which is an important host for recombinant protein production, was explored in this study. Experimental evidence showed a correlation between apparent isoelectric point distributions and the mobile phase conductivity. It was observed that the information contained in the isoelectric point (pI) value(s) obtained with a 2-DE routine showed a good correlation with the IEX chromatographic behavior, for a number of commercial adsorbents. This correlation was observed irrespective of the pH of the feedstock within the range 6 to 8. An initial prediction of protein ion-exchange chromatographic behavior could be possible utilizing an experimental approach based on the mentioned orthogonal methods. This technique is providing information that more closely resembles the separation behaviour observed with a complex biotechnological feedstock. [ABSTRACT FROM AUTHOR]

Abstract: This review focuses on analytical techniques used for separation and characterization of dendrimers and their derivatives. These macromolecules have been attractive material for a development of new drug carriers and imaging agents. They are also interesting for many biological and industrial applications. The review mentions a few of them. [Copyright &y& Elsevier]

An extension of the unified equation of chromatography to directly access reaction rate constants k1 of first-order reaction in on-column chromatography is presented. This extended equation reflects different response factors in the detection of the reaction educt and product which arise from structural changes by elimination or addition, e.g., under pseudo-first-order reaction conditions. The reaction rate constants k1 and Gibbs activation energies $$ \Delta G^{ \ne } $$ of first-order reactions taking place in a chromatographic system can be directly calculated from the chromatographic parameters, i.e., retention times of the educt E and product P ( $$ t_{\text{R}}^{\text{A}} $$ and $$ t_{\text{R}}^{\text{B}} $$), peak widths at half height ( wA and wB), the relative plateau height ( hp) of the conversion profile, and the individual response factors fA and fB. The evaluation of on-column reaction gas chromatographic experiments is exemplified by the evaluation of elution profiles obtained by ring-closing metathesis reaction of N, N-diallytrifluoroacetamide in presence of Grubbs second-generation catalyst, dissolved in polydimethylsiloxane (GE SE 30). [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

Gram negative bacteria frequently synthesize a great number of lipopolysaccharides (LPS) molecular species. The high LPS structural heterogeneity and its trend to conform molecular aggregates make the fraction of its molecular species extremely difficult. The application of chromatographic methods individually has allowed the obtainment of little homogeneous LPS fractions. With the combination of orthogonal chromatographic principles, only the purification of the simplest rough type LPS up to chemical homogeneity has been reached. This has determined that efforts aimed at more homogeneous LPS isolation is focused on the use of electrophoresis in slab gel. Electrophoresis methods are capable of separating species of similar molecular masses next to from the most complex smooth type LPS. Consequently upon this basis, a new methodology allowing the isolation of intact LPS of either rough or smooth types up to electrophoretic homogeneity has been developed. Under such methodology, sensible structural analysis through mass spectrometry and LAL (Limulus Amebocyte Lysate) activity of LPS individual species is feasible, composed of just a few chemical species. This methodology has proved the possible way of combining electrophoresis with other orthogonal separation principles, a further step which could guarantee the obtainment of chemically homogeneous preparations from complex LPS mixtures. [ABSTRACT FROM AUTHOR]

Gram negative bacteria frequently synthesize a great number of lipopolysaccharides (LPS) molecular species, the high LPS structural heterogeneity and its trend to conform molecular aggregates make the functioning of its molecular species extremely difficult. The application of chromatographic methods individually has allowed the obtainment of little homogeneous LPS fractions. With the combination of orthogonal chromatographic principles, only the purification of the simplest rough type LPS up to chemical homogeneity has been reached. This has determined that efforts aimed at more homogeneous LPS isolation is focused on the use of electrophoresis in smooth gel. Electrophoresis methods are capable of separating species of molecular masses next to the most complex smooth type LPS. Consequently upon this basis, a new methodology allowing the isolation of intact LPS of either rough or smooth types up to electrophoretic homogeneity has been developed. Under such methodology, sensible structural analysis through mass spectrometry and LAL (Limulus Amebocyte Lysate) activity of LPS individual species is feasible, composed of just a few chemical species. This methodology has proved the possible way of combining electrophoresis with other orthogonal separation principles, a further step which could guarantee the obtainment of chemically homogeneous preparations from complex LPS mixtures. [ABSTRACT FROM AUTHOR]

Abstract: In this review, we discuss three different approaches to liquid-liquid extraction (LLE) driven by an electrical field (dc): [(1)] electro extraction, by which ionic analytes are extracted from a stagnant organic solution (immiscible with water) into water; [(2)] electrochemically-modulated LLE (known as ITIES extraction, where ITIES means “interface between two immiscible electrolyte solutions”), by which ionic analytes are extracted from a flowing aqueous sample and into a stationary organo-gel; and, [(3)] electro-membrane extraction, by which ionic analytes are extracted from an agitated aqueous sample, through an organic solvent (supported liquid membrane) sustained in the pores in the wall of a porous hollow fiber, and into an aqueous acceptor inside the lumen of the hollow fiber. We review the literature with respect to these techniques, which we compare in terms of performance and working principles, and outline the promising aspects of using electrical fields to enhance and to manipulate LLE. In conclusion, we identify LLE driven by electrical fields as an important field for future development in sample preparation for chromatography and electrophoresis. [Copyright &y& Elsevier]

Abstract: Casein is used as an additive in binders or paints and as such exhibits unique properties which might be based on the properties of certain subproteins in the complex whole casein mixture. Therefore, the separation of whole casein (CN) from cow milk was performed on a gram scale in order to yield sufficient amounts of the protein subfractions α-, β-, and κ-casein for further testing utilizing fast protein liquid chromatography (FPLC) and preceding enrichment in the case of κ-casein. Construction chemical grade casein, which differs in quality from dairy grade casein, was used for separation because of our interest in the proteins responsible for plastification of cementitious systems such as mortar. The solubilized proteins were separated chromatographically via ion exchange chromatography (IEX) and the subsequently desalted protein fractions were tested for purity by isoelectric focusing (IEF). [Copyright &y& Elsevier]

Basic knowledge of equilibrium conditions and the association behavior of any dynamic chemical system is important if one is to evaluate and understand that system. Binding constants for molecular associations can be determined by a variety of different approaches, each with its own advantages and disadvantages. This review examines various chromatographic and electrophoretic methods that have been developed to study dye-protein interactions. An overview of each technique is presented, along with a discussion of its strengths, weaknesses, and potential applications. Examples are provided that illustrate the use of these methods in determining the overall extent of dye-protein binding. [ABSTRACT FROM AUTHOR]

Abstract: Nearly one-third of all genes in various organisms encode membrane-associated proteins that participate in numerous protein-protein interactions important to the processes of life. However, membrane protein interactions pose significant challenges due to the need to solubilize membranes without disrupting protein–protein interactions. Traditionally, analysis of isolated protein complexes by high-resolution 2D gel electrophoresis has been the main method used to obtain an overall picture of proteome constituents and interactions. However, this method is time consuming, labor intensive, detects only abundant proteins and is limited with respect to the coverage required to elucidate large interaction networks. In this review, we discuss the application of various methods to elucidate interactions involving membrane proteins. These techniques include methods for the direct isolation of single complexes or interactors as well as methods for characterization of entire subcellular and cellular interactomes. [Copyright &y& Elsevier]

Abstract: When an analyte injected in a zonal separation method (chromatography, capillary zone electrophoresis, field-flow fractionation) is not highly diluted in the carrier fluid, the retention ratio, R – or ratio of the cross-sectional average migration velocity of the analyte to that of the carrier fluid – depends on the local concentration, c, of the center of mass of the analyte zone, and the zone migration occurs in non-linear conditions. Because the zone broadens as it moves along the separator, R varies continuously from the inlet to the outlet of the separator. That concentration, c eff, for which R(c eff) is equal to the length-averaged apparent retention ratio, R app, is called effective concentration, and that distance, z eff, from the separator inlet, for which c(z eff) is equal to c eff, i.e. for which R(z eff) is equal to R app, is called effective position. Assuming that near the onset the non-linear behavior, R(c), is a linear function, values of R app, c eff and z eff have been computed in a wide range of operating conditions which are typical of situations encountered in capillary zone electrophoresis, liquid chromatography, or field-flow fractionation. Computations have been performed both in presence and in absence of the dispersion arising from the concentration dependence of the analyte migration rate (called thermodynamic dispersion in chromatography or electromigration dispersion in capillary zone electrophoresis). It is found that, whatever the range of analyte concentration covered from inlet to outlet of the separator, c eff is always close to two times the analyte concentration, c out, at the outlet of the separator, and z eff between one-fourth and one-third of the separator length. As c out is easily determined from the peak recorded by a concentration-sensitive detector, a simple pragmatic expression is given for the estimation of c eff. This effective concentration is the appropriate concentration to be used for comparing predictions of theoretical models of R(c) with experimental retention data. This is of particular interest for validating such models in field-flow fractionation. [Copyright &y& Elsevier]

Abstract: Almost all proteins are expressed in several variants, also known as isoforms. Individual protein variants differ by modifications of the individual amino acid side chains, or the N- or C-terminus. Typical modifications are glycosylation, phosphorylation, acetylation, methylation, deamidation or oxidation. It is of utmost interest to either get a quantitative picture of the variants of a particular protein or to separate the variants in order to be able to identify their molecular structure. Protein variants are present in native as well as in recombinant proteins. In the case of protein production it is interesting, how variants are generated during fermentation, purification processes, storage, and how present individual variants influence the biological activity. This review provides a comparison of chromatographic and electrophoretic separation methods to analyze and to prepare protein variants. [Copyright &y& Elsevier]

Proteins as a product from genetic information execute and determine how development, growth, aging and disease factors are orchestrated within the lifetime of an organism. Differential protein expression and/or modification are always context dependent i.e. they happen within a specific context of a tissue, organ, environmental situation and individual fate. Consequently, the function/dysfunction (in a certain disease) of a specific gene cannot be predicted comprehensively by its sequence only. Genetic information can only be understood when genes and proteins are analyzed in the context of the biological system and specific networks they are involved in. In regard to neurodegenerative diseases such as Alzheimer’s (AD) and Parkinson’s disease (PD) many proteins are known for long years to be the cause or the consequence of the pathomechanism of the respective disease. The treatment of these neurodegenerative diseases represents a major challenge for the pharmaceutical industry, whereas the understanding of their pathogenesis is still in its infancy. With the development of several powerful techniques for proteome analysis it is now possible to investigate the expression of thousands of proteins in single cells, tissues or whole organisms at the same time. These developments opened new doors in medical sciences, and identification of cellular alterations associated with e.g. neurodegeneration will result in the identification of novel diagnostic as well as therapeutic targets. In this review, general considerations and strategies of proteomics technologies, the advantages and challenges as well as the special needs for analyzing brain tissue in the context of AD and AD are described and summarized. [ABSTRACT FROM AUTHOR]

Requirements of regulatory organisations for the industry are necessaries in the first stages of the investigation and development processes of biotechnological products, about validation of analytical methods that demonstrate the identity, strength, quality and purity of the products. In this work, we standardised some physical, chemical and immunochemical methods for the characterisation of molecules as antigens, allergens and some fungicide molecules. Materials and methods. Chromatography methods: a) Gel filtration in Superose 12, Sephacryl S-100, Sephacryl S-1000, Sepharose CL-4B for the determination of size of outer membrane proteins (OMP) from Vibrio cholerae, Pseudomona, Shigella, Leptospira ssp and some antigens of vaccine conjugates. Thin Layer Chromatography (TLC) for the separation of chromophore compounds from Pseudomona and for the evaluation of metabolism carbohydrates. b) Electrophoresis method in polyacylamide gels in Phast System for the antigens identity of OMP and for the evaluation of identity and amount of the allergen proteins from Dermatophagoides siboney. c) Immunochemical method. Dot Blot for the identity of antigens in vaccine conjugates. Methods were classified according to the applications recommended by OMS: Specificity, Accuracy, Precision, Linearity, Range, Robustness. Results and Conclusions. Results are adequate according with the references for that methods. It will permits security and confidence for the characterisation of molecules. [ABSTRACT FROM AUTHOR]

Abstract: This review is presented of chromatography and electromigration methods currently in use to determine sugars in traditional Chinese drugs: gas chromatography (GC), high-performance liquid chromatography (HPLC), ion-exchange chromatography, gel column chromatography (GCC), paper chromatography (PC) and thin layer chromatography (TLC), capillary electrophoresis (CE) and gel electrophoresis (GEP). The detection methods combined with above separation methods including ultra-violet, mass spectra, fluorescent light, refractive index (RI), electrochemical detection are also described. For the complicacy of structural analysis of polysaccharides in traditional Chinese drugs, the hyphenation procedures concerned with this analysis are introduced in this article too. [Copyright &y& Elsevier]

Venom from the endoparasitoid wasp Pimpla turionellae L. (Hymenoptera; Ichneumonidae) was isolated in pure form. Total protein determination indicated an average value of 0.04 µg protein per venom sac. The molecular weights of the venom components were estimated with reference to molecular weight markers and reference proteins by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). Analysis indicated that venom primarily contains proteins with molecular weights between 20 and 106 kDa. The presence of melittin and apamin in wasp venom was shown by SDS-PAGE and reversed-phase high-performance liquid chromatography (HPLC). Infrared spectroscopic data confirmed the acidic nature of the venom and the presence of amines, peptides, proteins, and enzymes in the venom. Venom noradrenaline was separated using thin-layer chromatography and verified by infrared spectroscopy. [ABSTRACT FROM AUTHOR]

Because immunoassay responds to epitopes, and many molecules share the same peptide epitope, it is very difficult to obtain an accurate understanding of peptides, their creation and hydrolysis, in biological systems. Separate-and-detect approaches have merit in that the many active peptides and inactive fragments of a particular system can be separately determined. This review discusses the separation, by chromatography and capillary electrophoresis, and detection, by absorbance, fluorescence, electrochemistry, and immunoassay techniques. When separation preconcentration is accompanied by laser-induced fluorescence or biuret-based electrochemical detection, nM-pM detection limits are obtained. [Copyright &y& Elsevier]

Adult and young camel ceruloplasmin (Cp) were isolated and purified using the single-step chromatography on amino ethyl-activated sepharose. There are no differences between the adult and the young camel protein. The molecular mass of the protein, as estimated by SDS-PAGE (denaturant conditions), was approximately 130 000 Da. The electrophoretic mobility of camel Cp is slightly higher as compared to human and sheep protein suggesting that the camel Cp is homogeneous, compact and more acid. The copper content was estimated to be 5.8±0.3 atoms per molecule. The spectrocopic feature includes an absorption maximum at 610 nm, which could be attributed to type 1 copper. The EPR spectrum was completely devoid of any typical signal of the type 2 copper. The kinetic parameters of the adult camel Cp for the specific activity as p-phenylendiamine oxidase were determined as Km=0.42 mM and Vmax=0.93 μM NADH/mn/mg Cp. The optimum pH for the activity was 5.7. [Copyright &y& Elsevier]

The special luminescent features of some terbium(III) chelates and the appropriate selection of experimental factors give rise to a wide variety of analytical applications such as direct determination of organic analytes, immunodiagnostic assays and chromatographic and electrophoretic methods, which are jointly presented and discussed in this review. The requirements for sensitizing terbium luminescence provide a high selectivity to these methods. Terbium-sensitized luminescence can be easily adapted to different analytical fields and shows a great analytical versatility. [Copyright &y& Elsevier]