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Background and Aims Cress seeds release allelochemicals that over-stimulate the elongation of hypocotyls of neighbouring (potentially competing) seedlings and inhibit their root growth. The hypocotyl promoter is potassium, but the root inhibitor was unidentified; its nature is investigated here. Methods Low-molecular-weight cress-seed exudate (LCSE) from imbibed Lepidium sativum seeds was fractionated by phase partitioning, paper chromatography, high-voltage electrophoresis and gel-permeation chromatography (on Bio-Gel P-2). Fractions, compared with pure potassium salts, were bioassayed for effects on Amaranthus caudatus seedling growth in the dark for 4 days. Key Results The LCSE robustly promoted amaranth hypocotyl elongation and inhibited root growth. The hypocotyl inhibitor was non-volatile, hot acid stable, hydrophilic and resistant to incineration, as expected for K+. The root inhibitor(s) had similar properties but were organic (activity lost on incineration). The root inhibitor(s) remained in the aqueous phase (at pH 2.0, 6.5 and 9.0) when partitioned against butan-1-ol or toluene, and were thus hydrophilic. Activity was diminished after electrophoresis, but the remaining root inhibitors were neutral. They became undetectable after paper chromatography; therefore, they probably comprised multiple compounds, which separated from each other, in part, during fractionation. On gel-permeation chromatography, the root inhibitor co-eluted with hexoses. Conclusions Cress-seed allelochemicals inhibiting root growth are different from the agent (K+) that over-stimulates hypocotyl elongation and the former probably comprise a mixture of small, non-volatile, hydrophilic, organic substances. Abundant components identified chromatographically and by electrophoresis in cress-seed exudate fitting this description include glucose, fructose, sucrose and galacturonic acid. However, none of these sugars co-chromatographed and co-electrophoresed with the root-inhibitory principle of LCSE, and none of them (in pure form at naturally occurring concentrations) inhibited root growth. We conclude that the root-inhibiting allelochemicals of cress-seed exudate remain unidentified. [ABSTRACT FROM AUTHOR]

Abstract Flavonoids are plant-derived compounds that have several health benefits, including antioxidative, anti-inflammatory, anti-mutagenic, and anti-carcinogenic effects. Quercetin is a flavonoid that is widely present in various fruits, vegetables, and drinks. Accurate determination of quercetin in different samples is of great importance for its potential health benefits. This review, is an overview of sample preparation and determination methods for quercetin in diverse matrices. Previous research on sample preparation and determination methods for quercetin are summarized, highlighting the advantages and disadvantages of each method and providing insights into recent developments in quercetin sample treatment. Various analytical techniques are discussed including spectroscopic, chromatographic, electrophoretic, and electrochemical methods for the determination of quercetin and its derivatives in different samples. UV–Vis (Ultraviolet–visible) spectrophotometry is simple and inexpensive but lacks selectivity. Chromatographic techniques (HPLC, GC) offer selectivity and sensitivity, while electrophoretic and electrochemical methods provide high resolution and low detection limits, respectively. The aim of this review is to comprehensively explore the determination methods for quercetin and quercetin glycosides in diverse matrices, with emphasis on pharmaceutical and biological samples. The review also provides a theoretical basis for method development and application for the analysis of quercetin and quercetin glycosides in real samples. [ABSTRACT FROM AUTHOR]

Glycated hemoglobin (HbA1c) is used to monitor the long-term management of diabetes and reflects the average blood glucose level over the past three months. Hb J is an alphaglobin gene variant that occurs less commonly but can interfere with the HbA1c result. This case report presents two cases of abnormally high HbA1c in patients with Hb J using the high-performance liquid chromatography (HPLC) method and repeated value using the capillary electrophoresis (CE) method. The first case was a 26 years old female Malay patient, presenting at 25 weeks gestation with diabetes mellitus (DM). Her HbA1c results from HPLC showed persistently high level (> 18.5%, > 179 mmol/mol) despite optimum diabetic control (fasting blood sugar (FBS) range 4.0--6.1 mmol/L). The second case was a 62-year-old female Malay with type 2 DM. Her HbA1c results from HPLC was also persistently high (> 18.5%, > 1;79 mmol/mol) despite good diabetic control (FBS average 5.0--7.0 mmol/L). Both patients' hemoglobin analysis reports were suggestive of Hb J. Repeated HbA1c using CE were 6.0% (42 mmol/mol) and 8.1% (65 mmol/mol), respectively, and supported the presence of the Hb J variant peak. HbA1c measurement in patients with a variant should be interpreted with caution to avoid misdiagnosis and mismanagement in these kinds of patients. [ABSTRACT FROM AUTHOR]

HbA1c measurement is very useful for the follow-up and detection of glycemic disorder, since it is easier and faster test and is independent of the patient's fasting status. In this study, we aimed to perform the comparative evaluation of 3 different methods for HbA1c measurement including capillary electrophoresis, immunoturbidimetric assay and high-performance liquid chromatography-HPLC. This study comprised 134 leftover whole blood samples obtained from the subjects submitted for routine HbA1c testing. All blood samples were collected in EDTA-containing vacutainer tubes. The HbA1c levels were measured simultaneously using three different methods. Bias estimation, method agreement and concordance between the pairwise methods comparisons were evaluated by Bland–Altman plot and Passing–Bablok regression test. HbA1c levels ranged from 3.8% to 13.4% and measured by three different methods to make the comparison. The median values of samples based on immunoturbidimetric method (6.05%, IQR = 1.80) were higher than capillary electrophoresis method (5.90%, IQR = 1.80) and HPLC (5.85%, IQR = 1.80) method. The study group was classified into three subgroups based on the HbA1c levels measured with the HPLC method: Group 1 (n = 57) was composed of subjects with HbA1c levels less than 5.7%, Group 2 (n = 35) had HbA1c levels between 5.7% and 6.4%, Group 3 (n = 42) had HbA1c levels equal and more than 6.5%. To our knowledge, there is no study evaluating the HbA1c measurement on the Atellica® CH 930 Analyzer. We compared the Atellica®CH930 Analyzer with both HPLC and capillary electrophoresis. The Atellica®CH930 Analyzer showed acceptable performance and a strong correlation with both mentioned methods. [ABSTRACT FROM AUTHOR]

Ricinus communis L. (Euphorbiaceae), the local name jarak kepyar, is a tropical plant that is widely planted in East Java, Indonesia. The leaves and seeds of this plant have been traditionally utilized to cure liver disease, stomach disorders, inflammation, fever, headache, etc. Ricin, one of the most toxic substances known isolated from R. communis L. seeds, is a heterodimeric two-domain polypeptide protein that includes chain A (30 kDa) and a slightly bigger chain B (35 kDa). The technique to distinguish and separate ricin is not much reported. In this study, we analyzed the crude ricin extracted from R. communis L. seeds originated from Nganjuk, East Java, Indonesia. The techniques used were (1) liquid chromatography (LC); (2) column liquid chromatography (CLC); and (2) fast protein liquid chromatography (FPLC), followed by SDS-PAGE. Results show that all techniques positively confirm the presence of ricin protein indicated by a doublet peak in all chromatograms. This study might contribute to understanding the biological and chemical properties of the ricin protein of R. communis L. seeds. [ABSTRACT FROM AUTHOR]

Objective The purpose of this study was to compare the performances of and evaluate the agreement among glycated hemoglobin values analyzed by using National Glycohemoglobin Standardization Program-certified and International Federation of Clinical Chemistry-standardized analyzers. This cross-sectional study was conducted at the Armed Forces Institute of Pathology, Department of Chemical Pathology from March 2019 to May 2019. Methods Glycated hemoglobin (HbA1c) was measured in the blood specimens from 100 patients on an ADVIA 1800 by a turbidimetric inhibitory immunoassay (TINIA), Sebia instrument by electrophoresis, and Bio-Rad Variant II Turbo system by high-performance liquid chromatography (HPLC). Quantitative variables were calculated as the mean ± standard deviation (SD). Precision and method comparisons were carried out according to Clinical and Laboratory Standards Institute recommendations. The results obtained from each analyzer were compared by correlation analysis. Method comparison was done by linear regression and Bland-Altman plots using the SPSS software version 24. Results The mean ± SD HbA1c values from TINIA, electrophoresis, and HPLC were 7.188% ± 1.89%, 7.164% ± 1.866%, and 7.160% ± 1.85%, respectively. The between-run coefficients of variation for TINIA, electrophoresis, and HPLC were 0.64%, 0.61%, and 0.60%, respectively. All 3 showed good correlation (TINIA, R 2 =.994, P  = .00; electrophoresis, R 2 =.992, P  = 0.00; and HPLC, R 2 =.994, P  = 0.00). Conclusion The good clinical agreements of HbA1c and strong correlations between analyzers indicate that these analyzers can be used interchangeably. [ABSTRACT FROM AUTHOR]

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]

Citalopram (CIT) is a highly selective serotonin reuptake inhibitor (SSRI) frequently used in the treatment of major depressive disorders. It has a chiral centre in its structure and is used in therapy both as a racemic mixture (R,S‐CIT) and a pure enantiomer (S‐CIT). The differences between the pharmacokinetic and pharmacological profiles of the two enantiomers are well established. Consequently, the development of new efficient chiral analysis methods for their enantiomeric separation is a topic of great actuality. CIT metabolism is stereoselective as it is metabolized in chiral active metabolites, which retain considerable SSRI activity and contribute to the pharmacological effect. Chiral analytical methods are employed for the determination of enantiomeric ratio in pharmaceutical preparations and for monitoring the enantiomer levels in biological samples for therapeutic and toxicologic purposes. The current study reviews the published literature for the chiral analysis of CIT and its metabolites based on chromatographic and electrophoretic methods coupled with UV, fluorescence and mass spectrometry detectors. [ABSTRACT FROM AUTHOR]

Enzymes from organisms that are adapted to the existence at low temperatures attract significant attention of scientists as a perspective objects not only on a practical point of view, but also as a valuable tools for conducting basic research. This is due to unusual environmental conditions (low temperature, high hydrostatic pressure, low illumination), as well as a significant level of economic profitability due to the widespread of marine hydrobionts and high efficiency of psychrophilic enzymes in comparison with their mesophilic and thermophilic analogues. The expediency of using the hydrobionts of the Antarctic region Parborlasia corrugatus and Sterechinus neumayeri as a source for producing individual enzymes was indicated by the results of electrophoretic analysis of enzymes from hydrobionts tissues extract, so it was concluded that the total extract contained a number of enzymes that were active with gelatin and fibrinogen. As a result of a combination of several chromatographic stages, which included affinity chromatography on Blue Sepharose 6 FF column and size exclusion chromatography on Superdex 75 PG and Superdex 200 PG columns, from the total hydrobiont tissue extract were obtained fractions of hydrolytic enzymes. From the total tissues extract of both hydrobionts which was explored were isolated 4 fractions which showed gelatinase activity. Also from the tissues of Sterechinus neumayeri a fraction containing high-molecular enzymes capable of cleaving fibrinogen was isolated. The developed method of two-stage chromatography can be used further as a basis for optimizing the obtaining of enzymes of a similar spectrum of action from other objects. [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]

The study examines the influence of artificial aging on the stability of collagen within the parchments. Aging of the parchments was generated by heating at 70°C in a dry oven for 72 h as well as by keeping the parchment samples in the solution of artificial sweat. Sodium dodecyl sulfate polyacrylamide gel electrophoresis and size-exclusion chromatography were utilised to investigate the state of proteins within the parchment samples after exposure to heating and artificial sweat. The study has shown that the accelerated aging of the parchment results in marked change of protein and peptide concentrations, release of collagen chains, as well as leads to the alteration in the peptide compositions. [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]

Objective: Snapshot imaging has several advantages in automated gel electrophoresis compared with the finish-line method in capillary electrophoresis; this comes at the expense of resolution. A novel signal processing algorithm is proposed enabling a multisnapshot imaging (MSI) modality whose objective is to substantially improve resolution. MSI takes multiple-captures in time as macromolecules are electrophoresed. Peaks from latter snapshots have high resolution, but low signal-to-noise ratio (SNR), while earlier snapshots have low resolution, but high SNR. Methods: Signals at different capture-times are related by a scale-in-separation, shift-in-separation, and amplitude gain. The proposed method realigns the multiple captures using least-squares and fuses them. The algorithm accounts for the partial waveforms observed as the chromatic peaks exit the sensor's field-of-view. Results: MSI improves resolution by approximately $\text{10}\%$ on average per minute of additional electrophoresis. Conclusions: Comprehensive analysis of the resolution quantified on several data sets demonstrates the effectiveness of MSI. Significance: MSI can double the resolution compared with traditional snap-shot imaging over a typical set of captures. [ABSTRACT FROM AUTHOR]

Abstract 3D printing is an emerging enabling technology that can facilitate the production of complex 3D structures in analytical chemistry, including the millifluidic, e.g. flow injection (FI), and microfluidic arenas. In this review, the potential of 3D printing for the fabrication of cost-effective millifluidic platforms incorporating on-line sample handling and separation is critically appraised against traditional configurations or manufacturing processes. Applications resorting to structures achievable with 3D printing, in some instances exploiting the surface chemistry of the printable material, are grouped under: (i) fluidic drivers, mixers and reactors, (ii) membrane separation, (iii) sorbent extraction/concentration, (iv) chromatographic and electrophoretic separation, and (v) sensing and detector housings. Summary tables are also presented for reported applications of on-line sample handling and separation in environmental and biochemical analysis. Graphical abstract Image 1 Highlights • 3D printing technologies for millifluidic systems. • Possibilities for on-line mixing and reaction in 3D printed devices. • Membrane separation including in situ membrane formation. • Solid phase extraction including in situ fabricated polymer-based columns. • Chromatographic and electrophoretic separations in 3D printed devices. [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]

Disaccharides are determined mainly for dietetic purposes, hence the most analyses are carried out for food and drink samples. Its content can also be used to profile groceries in order to identify the origin and quality of the products. They also can be an indicator of the rate of metabolism as well as for the control of some technological and biotechnological processes. Unfortunately most of technological analysis are performed with nonselective polarimetry methods. Sugars due to specific physicochemical properties of compounds are difficult to determine with classical analytical techniques. The most common disaccharides are composed of several types of monomers connected by a different configuration of the glycosidic bond, therefore, there are subject of the same characteristic reactions. This often enforces the need for pre-separation of sample components. Therefore, nowadays the most popular analytical methodologies for disaccharides determination are based on chromatographic and electrophoretic techniques. An alternative is enzymes application that allow both selective recognition of target analyte and its conversion to easy detected product, allowing detection by relatively simple conventional analytical methods. Another approach is the use of advanced chemometric methodologies for computing of data obtained from some spectroscopic techniques. This article is a review of the recent analytical literature devoted to non-selective and selective methods for disaccharide determination in real samples. [ABSTRACT FROM AUTHOR]

Application of lysozyme as a natural antimicrobial or preservative agent in food and pharmaceutical industry is well known. The antimicrobial effects of lysozyme can be expanded by conjugation with carbohydrates via Maillard reaction, however this natural reaction is a time consuming process. So in this study a new method microwave heating, was applied to Accelerate the Maillard reaction. Lysozyme was mixed with dextran and heated by microwave irradiation. The glycation extent was determined by SDS-PAGE electrophoresis, cation-exchange chromatography and sugar analysis. SDS-page pattern show that with increasing heating time a high molecular weight conjugates were appeared and maximum glycosylation was occurred after 4 minutes heating. The elution profiles (chromatograms) of the lysozyme–dextran conjugates compared the natural lysozyme showed that the conjugated peak shifted towards the higher molecular weight fraction and overlapped with the non conjugated proteins, indicated that lysozyme was covalently bound to dextran. These results suggest that Maillard reaction rate can be increase using microwave heating. [ABSTRACT FROM AUTHOR]

Separation and purification techniques are applied in many important fields, such as in the medical, chemical, metallurgical, environmental, and pharmaceutical industries. Recent advances in separation science and the urgent need for highly selective purification have necessitated a rapid progress with respect to the reagents, chemicals, and surfactants used in separation processes to attain a high efficiency and selectivity. Polymeric materials have attracted considerable interest, and they have been widely used as extractants, catalysts, and modifiers, in separation and purification processes. This review outlines the recent advances in the use of novel polymers, natural and synthetic, in different separation and purification techniques. Various separation techniques such as chromatography, crystallization, precipitation, distillation, electrophoresis, filtration, and mineral processing methods are discussed, and the polymers used in each method are described in terms of their properties, structure, and function. The application of polymers shows great promise in achieving a highly efficient separation, especially in the areas of membrane separation and water purification. The rational design of new multifunctional polymers with triggered functions presumably presents new opportunities for the development of advanced separation methods. [ABSTRACT FROM PUBLISHER]

Zwitterionic surfactants have unique properties for applications in separation methods and catalysis. Their properties and efficiencies depend on two main factors: surfactant structure and preferential interactions of zwitterionic surfactant interfaces with anions. Structural changes are related to hydrocarbon chain length, distance between charges, and type and order of functional groups in the polar head. Interactions of anions with zwitterionic micelles follow the Hofmeister series and change the surface charge. The interactions between surfactants and molecules/ions allow the rational control of separation by chromatography and micellar capillary electrophoresis; cloud point extraction; and stabilization and catalytic activity of biomolecules and nanoparticles. [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]

Proteolytic and lipolytic changes in cow milk were studied after addition of banana pseudostem juice (BPJ) for preservation. Raw cow milk added with 0.3 % (v/v) BPJ had a shelf life of 6 h at 30±2°C unlike control sample (without BPJ) which kept well for 4 h only under identical condition during storage. The proteolytic changes in raw cow milk due to addition of BPJ was studied by Sodium Dodecyl Sulphate Polyacrylamide Gel Electrophoresis (SDS-PAGE) and fatty acid composition was determined by Gas Liquid Chromatography (GLC) technique. The electrophoretic profile of casein of both control and BPJ treated cow milk samples exhibited casein band of molecular weight between 29 KD and 43 KD. The concentration of saturated and unsaturated fatty acids was found to be 65.97% and 29.66% in cow milk. No significant change in the electrophoretic profile of BPJ treated samples was observed during the study when compared with that of untreated milk samples. Non-significant differences in the contents of saturated and unsaturated fatty acids as well as in the individual fatty acid were observed in raw cow milk preserved with BPJ for 6 h at 30±2°C. Individual fatty acid present in cow milk also did not exhibit any significant change among themselves during storage. It is concluded that addition of 0.3 % (v/v) BPJ did not cause any significant change in the fat and protein quality of cow milk when stored at 30±2°C for 6 h as electrophoretic and fatty acid profile is concerned. [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]

Semen is a heterogeneous and complex cell suspension in a protein rich fluid with various functions, some of them well known, other still unexplained. The aim of the current research is focused on canine seminal plasma proteins and their functional relationship with capacitation of spermatozoa. Attempts were made to identify canine seminal plasma proteins with effect on sperm capacitation and motility. High- Performance Liquid Chromatography was done and 4 seminal plasma protein fractions were obtained and further characterized by electrophoresis (7.6 kDa - 200 kDa). Computer-assisted sperm analysis after incubation of spermatozoa with separated seminal plasma proteins revealed that Fraction 1, consisting of high molecular weight proteins (70 - 200 kDa), could increase the percentage of spermatozoa with progressive and rapid motility. Incubation with seminal plasma proteins from Fraction 1 leads to a significant increase of VCL (Curvilinear velocity) and decrease of LIN (Linearity) of spermatozoa, when compared to the other test samples and the control sample. Proteins with high molecular weight probably have the most significant influence on the process of hyperactivation and capacitation of canine spermatozoa. [ABSTRACT FROM AUTHOR]

It is widely accepted that some of the free d -amino acids play important biological role. d -Aspartate and d -serine formed in the central nervous system of higher vertebrates have neurotransmitter/neuromodulator function. Together with d -alanine they are distributed in various tissues and biological fluids. Studying their physiological and pathological significance requires their sensitive and accurate determination in biological samples. The various separation and detection methods used for their analysis are overviewed in the present paper. Our focus is mainly the quantitative performance and the analysis of real biospecimens. [ABSTRACT FROM AUTHOR]

Enantiomeric separation is an increasing research area, as well as the application of alternative solvents replacing classic volatile, flammable and toxic organic solvents. Among these novel solvents, chiral ionic liquids (CILs) have been widely used in sample preparation (extraction), gas chromatography, liquid chromatography, capillary electrophoresis and other techniques involved in enantioseparation. Likewise, surfactants and deep eutectic solvents have gained increasing attention in the last years because they are valid alternatives to CILs with a lower cost and/or diminished environmental impact. This review provides a comprehensive overview of the latest developments using these modern solvents applied to enantioseparations, focusing mainly on the applications of CILs. Furthermore, separation and preconcentration of chiral analytes in different matrices are also reviewed in this article. Articles published since 2017 to present were reviewed in this work. Critical discussion on their analytical application and future challenges related to their use are also included in this review. • Benefits and limitations of alternative solvents in chiral analytical chemistry. • Innovations on enantioseparation methods focusing on the applications of CILs. • New developments on LLE and SPE methods for enatioselective extraction are shown. [ABSTRACT FROM AUTHOR]

A multiweek protein purification suite, suitable for upper-division biochemistry or biotechnology undergraduate students, is described. Students work in small teams to isolate the enzyme lactate dehydrogenase (LDH) from a nontraditional tissue source, mammalian blood, using a sequence of three column chromatographic procedures: ion-exchange, size exclusion, and affinity chromatography. Protein and enzyme activity elution profiles are determined by graphical analysis of assay data collected using rapid microplate spectrophotometric assays. Students perform quantitative assays on LDH pools and use these data to build a purification table for use in evaluating the protocol. The protocol typically generates final overall fold-purifications from 1500 to 2500 and activity recoveries of 45-60%. Electrophoretic separations in both denaturing and native-gel format are analyzed both visually and by use of commercial digital analysis software to assess the isoenzyme pattern of isolated LDH and to further evaluate the purification. Assessment of student work revealed a high level of achievement of course learning goals that include development of critical thinking skills required to (1) critically evaluate an experimental protocol and (2) draw conclusions based on a variety of forms of experimental data. [ABSTRACT FROM AUTHOR]

Hemoglobinopathies are most common inherited disorders in the world; approximately 7 percent of the worldwide population and 5-6 percent of population of Iran are carriers. The hemoglobin disorders inherit as autosomal recessive and are very common in the Mediterranean area and much of the Asia and Africa. The control of this inherited disorders need to genetic counseling and accurate screening by more advanced and more accurate methods. This study explains features of current Iran hemoglobin disorders, nominates the accessible methods for screening them and introduces the capillary zone electrophoresis as a rapid and more accurate method. The required data were extracted of various articles and then for good explanation, current Iran hemoglobinopathies properties were showed in the tables and electropherograms of important hemoglobin disorders in Iran population were provided for help to interpretation results of blood tests by capillary zone electrophoresis method. Hemoglobin disorders are including thalassemias and hemoglobin variants; Disruption in the production and malfunction of globin chains cause types of hemoglobin disorders. We cannot introduce one of clinical laboratory tests as critical and basic method for screening and distinguishing types of inherited hemoglobin disorders as alone. For distinguishing the types of them must be prepared enough information and data of the hemoglobin disorders and for more accurate analysis must be used simultaneously different methods as gel electrophoresis, high performance liquid chromatography, isoelectric focusing, capillary zone electrophoresis or molecular tests. The capillary electrophoresis is an accurate and rapid method for screening types of the hemoglobin disorders. Other side this method cannot analyze all of them, so must be used biochemical, biophysical and molecular methods for confirmation the results. This review showed we can use the capillary electrophoresis and HPLC as two complementary methods for hemoglobinopathies screening. We can analyze by the methods more hemoglobin disorders and decrease more laboratory errors. Moreover, we must have patient history, hematological indices, information and data of types of hemoglobinopathies. The patient history and complete blood count results as red blood cell count, mean corpuscular volume, mean corpuscular hemoglobin and mean corpuscular hemoglobin concentration can be useful and helpful in screening the hemoglobin disorders and then distinguishing all of hemoglobin disorders. [ABSTRACT FROM AUTHOR]

A laboratory experiment for teaching protein separation and detection in an undergraduate biochemistry laboratory course is described. This experiment, performed in two, 4 h laboratory periods, incorporates guided inquiry principles to introduce students to the concepts behind and difficulties of protein purification. After using size-exclusion chromatography to separate a mixture of proteins, students utilize a colorimetric enzymatic assay and an immunoassay to determine the location of individual mixture components. Students proceed to determine the molecular weight of each protein using gel electrophoresis and generated mass spectrometric data. Completing this experiment provides students with an opportunity to expediently separate proteins while learning about protein characterization. [ABSTRACT FROM AUTHOR]

Camel milk cannot be coagulated with bovine chymosin, most likely due to major variations between the primary k casein structures of the two species. Recently we have shown that the crude gastric extracts (CGE) from adults' dromedaries provide satisfactory milk clotting activity and limited proteolytic activity towards the camel milk. In the present study, we have isolated and characterized the CGE from dromedary abomasum. The CGE was separated and purified by DEAE-Cellulose column chromatography and Sephacryl S200 gel filtration. From various collected fractions, we characterized two fractions (F3 and F5) presenting a milk clotting activity and were eluted at 0.1 M and 0.45 M NaCl respectively. Interestingly, the F5 fraction had the highest milk clotting activity. The purified enzyme was resolved as a single protein band on SDS-PAGE with a molecular weight estimated about 38 kDa which was not affected by the addition of β-mercaptoethanol. In native PAGE, the enzyme migrated as a single band having a high intensity with similar electophoretic mobility to that of porcine pepsin. Using two dimensional electrophoresis, we found that the band obtained from the native-PAGE was concentrated on a single spot, quite intense. [ABSTRACT FROM AUTHOR]

The potential of biased cyclical electrical field-flow fractionation (BCyElFFF), which applies the positive cycle voltage longer than the negative cycle voltage, for characterization of submicron particles, was investigated. Parameters affecting separation and retention such as voltage, frequency, and duty cycle were examined. The results suggest that the separation mechanism in BCyElFFF in many cases is more related to the size of particles, as is the case with normal ElFFF, in the studied conditions, than the electrophoretic mobility, which is what the theory predicts for CyElFFF. However, better resolution was obtained when separating using BCyElFFF mode than when using normal CyElFFF. BCyElFFF was able to demonstrate simultaneous baseline separations of a mixture of 0.04-, 0.1-, and 0.2-μm particles and near separation of 0.5-μm particles. This study has shown the applicability of BCyElFFF for separation and characterization of submicron particles greater than 0.1-μm in size, which had not been demonstrated previously. The separation and retention results suggest that for particles of this size, retention is based more on particle size than on electrophoretic mobility, which is contrary to existing theory for CyElFFF. [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

[Display omitted] Snakebite envenoming is a major issue in certain developing parts of the world, with tens of thousands of deaths and a multitude of lingering permanent medical conditions on a yearly basis as a result. Venoms consist of a plethora of biologically active compounds, mainly peptides and proteins, that can induce these effects. Snake venom characterisation, in terms of identifying and quantifying the venom toxin proteins in crude venoms, can aid in pinpointing the venom toxins responsible for pathologies observed in snakebite victims. It can also assist in developing a new generation of efficient antivenoms. To facilitate this characterisation process, several approaches have been developed, of which venomics, toxicovenomics and antivenomics are the most important ones and aim to map venom toxin composition, their toxic effects, and antivenom efficacy, respectively. Most venomics approaches include peptide-centric analyses of protein digests in combination with advanced separation and detection hardware and involve the use of generic and dedicated software tools for data processing. However, a shift towards protein-level, and even proteoform-level, analysis can be observed over the last few years. A variety of hyphenated intact protein separation techniques, including gel-eluted liquid fraction entrapment electrophoresis, OFFGEL, gel filtration and several (ultra)high pressure and nanoscale chromatographic separations can be named, which allow retention of intact or native states of toxin proteins with ever increasing resolutions. Similarly, rapid detection hardware advances on the mass spectrometry side, and labelling techniques, allow for increasingly sensitive and quantitative venom analysis and characterisation. Most venomics research includes several complementary analytical techniques performed in parallel, with each technique often leading to exclusive protein identifications but also showing significant overlap. The original venomics approach, developed by the Calvete group and termed "Snake venomics", is used most frequently and is the most profound methodology that has been advanced over the years, thereby resulting in sequentially further identification of venom toxin proteins based on previous results using increasingly in-depth characterisation approaches. The latest advances in this regard nowadays allow for quantitative analysis of all venom toxins in crude venoms, named "Absolute venomics". This review will focus on the analytical aspects of venomics for which sample preparation, separation, detection and quantitation techniques are discussed. Finally, a comparison between recently published venomics studies is made. [ABSTRACT FROM AUTHOR]

Pulsed electrochemical detection (PED) has progressed as a highly sensitive and selective detection technique following aqueous-based separation systems over the past three decades. The application of on-line pulsed potential cleaning to electrocatalytic noble metal electrodes has significantly increased the number of applications formerly achieved with conventional electrochemical (EC) detection. Electrochemical cells are easily miniaturized, providing the ability to apply detection by PED at microelectrodes and onto microchips utilizing electrophoretic separations. In addition, recent advances in PED waveforms and instrumentation have enabled the detection technique to be easily coupled with high pressure separation systems which require rapid detection to maintain separation integrity. As a result, advanced applications for the determination of carbohydrates as well as the expansion of PED for the detection of other organic aliphatic compounds have been recently accomplished. This review will focus on developments and methods utilizing PED following liquid chromatography (LC) and capillary electrophoresis (CE). Publications are reviewed in chronological order to emphasize the advancement of the detection method and the sustained relevance of its applications. [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]

Highlights: [•] The purified glucoamylase was a 57–62kDa polypeptide with pI 4.3–4.4. [•] Optimum temperature/pH, K m, V max and k cat of the enzyme were 70°C, 5, 0.33 (mgml−1), 0.095 (Uμg−1 min−1) and 158.3 (S−1), respectively. [•] Fe3+, Al3+ and Hg2+ inhibited, and Ag2+, Ca2+, Zn2+, Mg2+, Cd2+ ions and EDTA did not inhibit the enzyme considerably. [•] The purified enzyme may be useful for industrial starch processing. [ABSTRACT FROM AUTHOR]

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]

To determine how structural changes in antibodies are connected with aggregation, the structural areas of an antibody prone to and/or impacted by aggregation must be identified. In this work, the higher-order structure and biophysical properties of two different monoclonal antibody (m Ab) monomers were compared with their simplest aggregated form, that is, dimers that naturally occurred during normal production and storage conditions. A combination of hydrogen/deuterium exchange mass spectrometry and other biophysical measurements was used to make the comparison. The results show that the dimerization process for one of the m Ab monomers (m Ab1) displayed no differences in its deuterium uptake between monomer and dimer forms. However, the other m Ab monomer (m Ab2) showed subtle changes in hydrogen/deuterium exchange as compared with its dimer form. In this case, differences observed were located in specific functional regions of the CH2 domain and the hinge region between CH1 and CH2 domains. The importance and the implications of these changes on the antibody structure and mechanism of aggregation are discussed. © 2013 Wiley Periodicals, Inc. and the American Pharmacists Association J Pharm Sci 102:4315-4329, 2013 [ABSTRACT FROM AUTHOR]

Dextransucrase-producing (Gen Bank accession no. KC110687)Weissella cibariaJAG8 was isolated from apple. The cell-free extract containing dextransucrase with specific activity of 1.0 U/mg was purified by polyethylene glycol (PEG). A concentration of 33% (v/v) PEG-400 fractionation gave a specific activity of 20.0 U/mg, whereas 15% (w/v) PEG-1500 resulted in a specific activity of 10.6 U/mg. The PEG-400-purified enzyme was further purified by chromatography using a Sephacryl S-300HR column, which resulted in 37-fold purification with 37 U/mg. The non-denaturing sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) of column-purified enzyme showed a single homogenous band of 177 kDa by silver staining. The production of dextran was confirmed by in situ detection of the activity band using periodic acid–Schiff's base staining. The optimum assay conditions for dextransucrase were 35°C, pH 5.4, and 5.0% (w/v) sucrose concentration. The enzyme followed Michaelis–Menten kinetics with Kmof 13 mMand Vmax27.5 U/mg. The enzyme was stable in 10–500 mMsodium acetate buffer, pH 5.4. A 22% increase in enzyme activity was observed with 2 mMmagnesium chloride; 64% loss in enzyme activity was observed with 10 mMethylenediamine tetraacetic acid (EDTA), whereas a complete loss in activity was observed with 5Murea. The dextransucrase was stable up to 35°C and pH of 5.4 for 1 hr. [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]

Abstract: Colloidal semiconductor nanocrystals or quantum dots (QDs) are one of the most relevant developments in the fast-growing world of nanotechnology. Initially proposed as luminescent biological labels, they are finding new important fields of application in analytical chemistry, where their photoluminescent properties have been exploited in environmental monitoring, pharmaceutical and clinical analysis and food quality control. Despite the enormous variety of applications that have been developed, the automation of QDs-based analytical methodologies by resorting to automation tools such as continuous flow analysis and related techniques, which would allow to take advantage of particular features of the nanocrystals such as the versatile surface chemistry and ligand binding ability, the aptitude to generate reactive species, the possibility of encapsulation in different materials while retaining native luminescence providing the means for the implementation of renewable chemosensors or even the utilisation of more drastic and even stability impairing reaction conditions, is hitherto very limited. In this review, we provide insights into the analytical potential of quantum dots focusing on prospects of their utilisation in automated flow-based and flow-related approaches and the future outlook of QDs applications in chemical analysis. [Copyright &y& Elsevier]

This article presents the most recent research in analytical chemistry concerning the development of rapid methodologies covering the period from 2009 up until today. In this context, different useful analytical methods have been developed based mainly on typical techniques such as gas chromatography, liquid chromatography, mass spectrometry, electrophoresis, electroanalytical chemistry, and biosensors. The analytical features of these methods have allowed the analysis of samples of different natures, such as environmental, food, pharmaceutical, and biological type, in which wide classes of analytes are promptly determined. The main advantages of these methods are included and discussed in this review regarding novelty, rapidity, sensitivity, selectivity, and costs. It is concluded that the development of rapid methods is still a growing trend in analytical chemistry and that gas- and liquid-chromatography mainly coupled to different modes of mass spectrometry are the most common analytical techniques applied today. Regarding the matrices analyzed, most of the methods have been developed for food analysis, followed by biological and environmental matrices. [ABSTRACT FROM PUBLISHER]

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]

Abstract: Highly pure riproximin was isolated from the fruit kernels of Ximenia americana, a defined, seasonally available and potentially unlimited herbal source. The newly established purification procedure included an initial aqueous extraction, removal of lipids with chloroform and subsequent chromatographic purification steps on a strong anion exchange resin and lactosyl–Sepharose. Consistent purity and stable biological properties were shown over several purification batches. The purified, kernel-derived riproximin was characterized in comparison to the African plant material riproximin and revealed highly similar biochemical and biological properties but differences in the electrophoresis pattern and mass spectrometry peptide profile. Our results suggest that although the purified fruit kernel riproximin consists of a mixture of closely related isoforms, it provides a reliable basis for further research and development of this type II ribosome inactivating protein (RIP). [Copyright &y& Elsevier]

The article presents an undergraduate chemistry laboratory experiment that exposes students to the essentials of a greener, chemoenzymatic synthesis of vanillin using biotechnological processes. Topics include the production of vanillin through the enzymatic oxidation of vanillyl alcohol by the enzyme eugenol oxidase (EUGO), the experimental design, and safety considerations.

Abstract: Detection of d-amino acids in natural peptides has been, and remains a challenging task, as peptidyl isomerization is a peculiar and subtle posttranslational modification that does not induce any change in primary sequence or in physicochemical properties of the molecule such as molecular mass or pI. Therefore, the presence of a d-amino acid residue in a peptide chain is generally transparent to classical methods of peptide analysis (electrophoresis, chromatography, mass spectrometry, molecular biology). In this article, we will review the various experimental strategies and analytical techniques, which have been used to characterize and to study d-amino acid containing peptides in crustaceans. [Copyright &y& Elsevier]

Breast cancer is a progressive and potentially fatal disease that affects women of all ages. Like all progressive diseases, early and reliable diagnosis is the key for successful treatment and annihilation. Biomarkers serve as indicators of pathological, physiological, or pharmacological processes. Her2/neu, CA15.3, estrogen receptor (ER), progesterone receptor (PR), and cytokeratins are biomarkers that have been approved by the Food and Drug Administration for disease diagnosis, prognosis, and therapy selection. The structural and functional complexity of protein biomarkers and the heterogeneity of the breast cancer pathology present challenges to the scientific community. Here we review estrogen receptor-related putative breast cancer biomarkers, including those of putative breast cancer stem cells, a minor population of estrogen receptor negative tumor cells that retain the stem cell property of self-renewal. We also review a few promising cytoskeleton targets for ER alpha negative breast cancer. [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]

60-80% of the analysis time for a significant number of analytical methods is taken up by the preparation, treatment, and separation of individual sample components, and most of the chemicals and solvents involved in the analysis are consumed in this step. We will demonstrate that many emerging methods of analytical separation science can meet the requirements of green chemistry by reducing the use of solvents and other reagents, lowering energy consumption by increasing the speed of analysis, and by miniaturizing and making equipment portable. Although recent efforts to make high performance liquid chromatography greener are praiseworthy, capillary electrophoresis, which comprises a group of separation methods that use narrow-bore fused-silica capillaries, is especially promising. It is highly competitive with liquid chromatography, which is the biggest consumer of organic solvents in analytical chemistry. However, capillary electrophoresis has not received the recognition it deserves as a green separation method that consumes microscopic volumes of solvent. It is a technique that is sufficiently mature to promote the greening of analytical chemistry via miniaturization-the most auspicious development in contemporary analytical chemistry. In this review, we will discuss recent developments in greening chromatography, and demonstrate the potential of electrophoresis and microfluidics in this regard. [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: Proteins have a great influence on wine quality as they exhibit a various range of properties. In fact, they are involved among others in white wine turbidity, organoleptic characteristics and foam formation in sparkling wines. These compounds could also be of major interest for varietal differentiation, regarding wine authentication and traceability issues. To provide a better understanding of the role played by these biomolecules in wine processing and explore their potential applications, there is a manifest need for the quantification and characterization of each individual one in terms of sequence, structure and intrinsic and functional properties. We thus present an overview of preparative and analytical methods for the study of proteins in grape juices and wines, from routine techniques to dedicated methodologies. They include sample preparation with chromatographic methods for the purification and identification of proteins, quantification protocols and characterization procedures such as electrophoretic techniques, immunological methods, sequencing, mass spectrometry, physico-chemical and structural analyses, and so on. We expose advantages and limits of each technique and focus on the different but complementary information they can provide. Despite the past years advances in the field proteins identification, the elucidation of the full protein profile for grape juices and wines remains strenuous. Their interactions with other wine compounds make the challenge even harder. We therefore emphasize the requirement of the techniques to be refined and suggest the developments to be expected. [Copyright &y& Elsevier]