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Prof. Dr. Panne's ambition as an editor for ABC is to demonstrate that good analytical chemistry is at the core of many fundamental and applied scientific problems and innovations and will contribute to solving the grand challenges of our times. We continue to have a dynamic team of editors at ABC. [Extracted from the article]

[Display omitted] • This paper focuses on a novel analytical method based on packed-nanofibers solid-phase extraction coupled with HPLC-FLD to determine aflatoxins G1, B1, G2, B2 in foods, which contribute vitally to the application of nanoscience and material technology on the agricultural and food chemistry and analytical field. • This study confirmed that the as-synthesized electrospun nanofibers as adsorbent displays preferable potential practical application in the simultaneous pretreatment and analysis of toxins from various samples. • Under optimized conditions, one-step sample pretreatment integrating extraction, purification, enrichment and elution, was realized. The method can simultaneously process 12 samples within 5 min on a semi-automatic array SPE processor. A novel analytical method based on nanofiber-packed solid-phase extraction (PFSPE) combined with HPLC-FLD has been successfully developed and applied to determine aflatoxin B1, B2, G1, G2 in foods. In order to effectively adsorb analytes from complex food matrices, four types of nanofibers based on skeleton of polystyrene–polyvinyl pyrrolidone were prepared by electrospinning and applied as adsorbent to home-made solid-phase extraction device. The effects of type of nanofibers, pH of sample, type and concentration of salt ion, type of activation solvent, type and volume of eluent, amount of nanofibers, and extraction time on the adsorption/desorption were investigated and optimized. Under optimal conditions, the method showed satisfactory linear relationship, with limits of detection (LODs) of 0.07–0.17 ng g−1, intra-day and inter-day RSDs for spiked samples of 1.3–8.0 % and 1.9–5.8 %, and absolute recoveries in the range of 60.1–98.4 %. The results presented the great potential to be utilized to determine AFs in foodstuffs. [ABSTRACT FROM AUTHOR]

A new protease was isolated from the intestine of small red scorpionfish. After ammonium sulfate precipitation, the enzyme was purified to homogeneity by a two-step chromatography with 6.69% recovery and fivefold increase in specific activity. The molecular weight of the protease was about 24 kDa as estimated by size exclusion chromatography and sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The enzyme optimum pH and temperature were pH 10.0 and 40°C, respectively. The protease was stable at temperatures below 40°C and over a broad pH range (8.0-11.0). The Km and Kcat values were 0.36 mmol L-1 and 1.61 s-1, respectively. Interestingly, the enzyme presented specificity for casein, egg albumin, bovine serum albumin, and gelatin with obtained degrees of hydrolysis ranging from 3.14% to 6.58%, after 2 h of hydrolysis. Moreover, gluten hydrolysate analysis confirmed protein hydrolysis and solubilization. These results suggested the potential use of the protease in the preparation of food protein hydrolysates with interesting properties. [ABSTRACT FROM AUTHOR]

Surfactants are one of the most versatile group of chemicals used in various industrial processes. Their market is competitive, and manufacturers will have to expand surfactant production in ecofriendly and cost effective manner. Increasing interest in biosurfactants led to an intense research for environment friendly and cost-efficient production of biosurfactant. Structural diversity and functional properties of biosurfactants make them an attractive group of compounds for potential use in wide variety of industrial, environmental and biotechnological applications. Screening methods make task easier to obtain potential biosurfactant producing microorganisms. Variety of purification and analytical methods are available for biosurfactant structural characterization. This review aims to compile information on types and properties of biosurfactant, microbial screening methods as well as biosynthesis, extraction, purification and structural characterization of biosurfactant using rhamnolipid as a model biosurfactant. It also describes factors affecting rhamnolipid production. It gives an overview of oil recovery using biosurfactant from Pseudomonas aeruginosa . [ABSTRACT FROM AUTHOR]

The determination of the time (i.e., age) elapsed since the last purification of plutonium with chemical separation gives important information for monitoring nuclear activities related to reprocessing and nuclear weapon production. Although methods for the analysis of plutonium solutions have been extensively studied, few studies were conducted for the measurement of individual particles. In this work, a simple technique was developed for age determination of individual plutonium particles by a combination of single particle dissolution and measurement by inductively coupled plasma mass spectrometry (ICP-MS) without prior chemical separation. The analytical results of individual plutonium particles having an age of 5.98 y indicated that the use of 240 Pu/ 236 U ratios allowed for the determination of accurate ages, though that of 238 Pu/ 234 U and 239 Pu/ 235 U ratios was not suitable because of the contamination of natural uranium during the process of sample preparation. The developed technique is especially useful for the analysis of the samples containing a number of plutonium particles having different ages. [ABSTRACT FROM AUTHOR]

Highlights: [•] Efficient and automated sample preparation is a major bottleneck in NA analyses. [•] ITP uses electric field to selectively extract and purify NAs. [•] ITP-purified NA samples are compatible with downstream analytical assays. [•] Guidelines for the design of lysis and ITP separation chemistry are presented. [•] Examples of ITP sample preparation from blood, urine, and cell culture are reviewed. [ABSTRACT FROM AUTHOR]

Highlights: [•] Polysaccharide from Glossaulax didyma (GDPS) was purified. [•] Preliminary characterization of GDPS was investigated. [•] GDPS showed a significant immunostimulatory effect. [•] GDPS showed a significant hepatoprotective effect. [ABSTRACT FROM AUTHOR]

L-amino acid oxidase (LAAO) is attracting increasing attention due to its important functions. Diverse detection methods with their own properties have been developed for characterization of LAAO. In the present study, a simple, rapid, sensitive, cost-effective and reproducible method for quantitative in-gel determination of LAAO activity based on the visualization of Prussian blue-forming reaction is described. Coupled with SDS-PAGE, this Prussian blue agar assay can be directly used to determine the numbers and approximate molecular weights of LAAO in one step, allowing straightforward application for purification and sequence identification of LAAO from diverse samples. [ABSTRACT FROM AUTHOR]

An evaluation of the extraction of multiresidue pesticides from palm oil by liquid-liquid extraction/low-temperature purification (LLE/LTP) coupled with dispersive solid-phase extraction (d-SPE) as the cleanup procedure with the determination by liquid chromatography mass spectrometry using electrospray as the ionization source (LC-ESI-MS) was carried out. Optimization approaches were studied in terms of d-SPE to select efficiency of type and mass of adsorbents to obtain the highest recovery yield of pesticides and the lowest coextract fat residues in the final extract. The optimal conditions of d-SPE were obtained using 3 g of palm oil, 4 g anhydrous MgSO4, 150 mg of PSA, and 50 mg of GCB (PSA: GCB (3: 1w/w)). Recovery study was performed at three concentration levels (25,50, and 100 ng kg-1), yielding recovery rates between 71.8 and 112.4% except diuron with relative standard deviations of 3.2-15.1%. Detection and quantification limits were lower than 2.7 and 8.2 ng kg-1, respectively. The proposed method was successfully applied to the analysis of market-purchased palm oil samples from two different brands collected in Kuala Lumpur, showing its potential applicability and revealing the presence of some of the target species in the ng g-1 range. [ABSTRACT FROM AUTHOR]

Abstract: We have developed an efficient one-pot, two-step preparation of ethylene blue by eliminating aqueous work-ups and cumbersome purification techniques. Our procedure generates ethylene blue in good overall yields of 45–56% with approximately 95% purity, which is uncommon for the synthesis of a phenothiazinium salt. Due to its unique properties, ethylene blue has great potential for a broad range of biological applications and, as a result, an efficient procedure for the synthesis of ethylene blue is critical. [Copyright &y& Elsevier]

The article presents a study which explores the improved chemical synthesis of 2,9-dichloro-1,10-phenanthroline. The study uses all reagents and solvents of reagent grade without further purification unless specified wherein the melting points (mps) were identified on a WRS-1B digital melting point apparatus and are uncorrected. The study reveals that the conventional method leads in six steps and in low overall yields 44% from 1,10-phenanthroline and an improved synthesis of 2,9-dichloro-1,10-phenanthroline in 67% overall yield was observed.

Abstract: This study introduces the general method of differential scanning calorimetry (DSC) for the purity assessment of chemical reference substances (CRSs). Thirty high-purity chemical reference substances were calibrated by the DSC method and the uncertainty of the measurements was calculated. The DSC method provided comparable CRS purity and uncertainty results to the method based on principle of mass balance (mass balance method). Therefore, the DSC method can be used for the purity assessment of suitable CRS. Purity determination by DSC has the advantage of practicality, speed, reproducibility, no corresponding reference standard requirement and no sample preparation is required. The DSC method is complementary to the mass balance method for the assay of chemical reference substances. [Copyright &y& Elsevier]

Diammonium phosphate (DAP) is produced from industrial phosphoric acid that contains large amounts of anionic and cationic impurities (Co, Cu, Fe, Mn, Mo, Ni, Zn, F, As, Al, Hg, Pb and Cd). Consequently all those impurities will be found in DAP. However, the industrial DAP obtained can be used as fertilizers, but cannot be used for some industrial application like pharmaceutics and cosmetics. After purification, the price of DAP is three times more expensive than the same product before purification. The procedure for purification of industrial DAP is a recrystallization, by using several mixtures of solvents. The physicochemical characterization of this fertilizer upstream and downstream from the purification, through spectroscopic analyses and chemical analyses, shows that recrystallization eliminates impurities. Purified DAP was obtained, the physicochemical properties of which are comparable to those of the pure commercial DAP (Fisher). [ABSTRACT FROM AUTHOR]

Abstract: The polysaccharide of Opuntia ficus indica Mill. was isolated by water, and purified by Sephacryl S-400 HR column. The purity of polysaccharide was evaluated by HPLC coupled with gel permeation chromatography. Results showed that the neutral monosaccharide composition of O. ficus indica polysaccharide was rhamnose, arabinose, and glucose in a molar ratio of 1.00:2.98:2.57, with an average molecular weight of about 172,591Da. Further, its antioxidant capacities in vitro were respectively evaluated by the assays of inhibition of pyrogallol autoxidation, scavenging hydroxyl radical, and liver lipid peroxidation inhibiting. The crude water-soluble polysaccharide and purified polysaccharide showed notable free radical scavenging activity and hydroxyl radical-induced liver lipid peroxidation inhibiting ability, suggesting that O. ficus indica polysaccharide may be considered as a potential candidate for the natural antioxidants and possible health-promoting functional foods. [ABSTRACT FROM AUTHOR]

Abstract: Three polysaccharide fractions (DDP1-1, DDP2-1 and DDP3-1) were successfully purified from the crude polysaccharide of Dendrobium denneanum by DEAE-Cellulose and Sephadex G-200 column chromatography. The average molecular weights (Mws) of these fractions were 51.5, 26.1 and 6.95kDa, respectively. Monosaccharide components analysis indicated that DDP1-1 and DDP2-1 were composed of arabinose, xylose, mannose, glucose and galactose in a molar ratio of 1.00:2.82:57.11:140.82:7.76 and 1.00:1.62:1.18:77.5:7.79. DDP3-1 was composed of arabinose, mannose, glucose and galactose in a molar ratio of 1.00:1.03:8.84:2.00. On the basis of antioxidant test in vitro, DDP2-1 exhibited the highest antioxidant ability among these samples. [Copyright &y& Elsevier]

This paper discusses basic distinctions and challenges of available commercial process technologies for fractionation of phenol and acetone products, and for removal of contaminants therefrom. Theoretical improbability of complete removal of impurities from the desired products under fractionation process conditions is conclusively demonstrated. The challenge of achieving an adequate quality of desired products (i.e., of phenol, acetone, and α-methylstyrene) has been effectively met within the framework of state-of-the-art phenol/acetone production process. [ABSTRACT FROM AUTHOR]

Abstract  Composition and characteristics of lignosulfonic acids recovered from technical-grade ligno-sufonates were studied by IR spectroscopy, viscometry, and elemental and chemical analyses. The dependence of the chemical composition and characteristics of lignosulfonic acids on the procedures of their recovery and purification was examined. [ABSTRACT FROM AUTHOR]

The filtration process constitutes the beginning of chemical analyses. This process is often cumbersome and time consuming. Filtering processes become more important, especially for the continuous and automatic analysis studies in the natural environment, since samples are likely to become polluted by natural and human effects. This study deals with a new, relatively economical, robotic filter change system. Simple stepping motors are used for this system. The PIC 16F877 microcontroller serves to control motors. The system realizes the sampling and filtration processes in a fully automated manner. [ABSTRACT FROM AUTHOR]

The Wendler version of the Torgov-Ananchenko scheme of total steroid synthesis was shown to be applicable to the preparation of 6-oxaestra-1,3,5(10),8,14-pentaenes. Conditions for cyclodehydration of secosteroids thus obtained were found, which ensured isolation of the target compounds in a high yield without using chromatographic purification methods. [ABSTRACT FROM AUTHOR]

Presents the characterization and purity assessment of deoxynivalenol (DON) obtained from two commercial sources. Confirmation of DON structural identity by H and C-nuclear magnetic resonance (NMR) spectroscopy, gas chromatography (GC) and infrared total reflectance spectroscopy; Establishment of complete assignment for all signals; Similarity of the chromatograms for both samples; Confirmation of the DON structure; Absence of differences in the purity.

Analyses of triolein-containing semipermeable membrane devices (SPMDs) have sometimes been impeded by interferences caused by impurities endemic to triolein that codialyze with the analytes. Oleic acid and methyl oleate have been the most troublesome of these impurities because of their relatively high concentrations in triolein and because significant residues of both can persist even after size exclusion chromatographic (SEC) fractionation. These residues have also been blamed for false-positive signals during bioindicator testing of SPMD dialysates. To prevent these problems, a simple, cost-effective procedure was developed for purifying triolein destined for use in SPMDs: the bulk triolein is repeatedly (6×) partitioned against methanol. Tests of the procedure show that 14C-oleic acid is completely removed from the triolein. After SEC fractionation, dialysates of standard-size SPMDs made with the purified triolein contain less than 5 μg of methyl oleate as compared to sometimes more than 500 μg for dialysates (also after SEC) of SPMDs made with unpurified triolein. Gas chromatographic analyses with flame ionization and electron capture detection show that the purification treatment also greatly reduces the number and size of peaks caused by unidentified contaminants in the triolein. Microtox basic assay of dialysates of SPMDs shows that those made with the purified triolein have lower acute toxicities than dialysates of SPMDs made with unpurified triolein. Yeast estrogen screen (YES) testing of SPMDs fabricated with unpurified and purified triolein demonstrates that the purification process removes all background estrogenic activity. [Copyright &y& Elsevier]

The results reported in the present paper and N-terminal sequence homologies established by other authors strongly support the assumption that the gastric protease previously called bovine pepsin I or bovine pepsin B belongs to the aspartate protease group and corresponds to gastricsin (or pepsin C) (EC 3.4.23.3) from other species. Bovine gastricsin was prepared from commercial extracts of adult bovine veils by a procedure involving DEAE-cellulose chromatography, gel filtration on Sephacryl S-200 and a further DEAE-cellulose chromatography. The preparation thus obtained was shown to be free of chymosin and bovine pepsin A by immunodiffusion, selective inactivation in urea and isoelectric focusing. Us molecular weight was estimated by gel filtration to be 32800. Bovine gastricsin displayed microheterogeneity on isoelectric focusing with pi values of the components ranging from 3.5 to 4.0. Chromatography of bovine gastricsin on hydroxyapatite separated three fractions, none of them being homogeneous by isoelectric focusing. Concanavalin-A—Sepharose 4B bound bovine gastricsin to some extent, but without any significant fractionation. Proteolytic activity could be detected directly on the isoelectric focusing gel for all the components of gastricsin and its fractions from hydroxyapatite and concanavalin-A—Sepharose 4B. Bovine gastricsin and its fractions from hydroxyapatite have similar amino acid compositions, different from those of bovine chymosin and pepsin A but obviously related to those of human, simian and porcine gastricsins. Bovine gastricsin which is inactivated by reaction with diazoacetyl-DL-norleucine methyl ester and with 1,2-epoxy-(p-nitrophenoxy)propane in a 1:1 and 1:2 stoichiometry, respectively, is able to hydrolyse a synthetic hexapeptide, Leu-Ser-Phe(NO2)-Nle-Ala-Leu-OMe, used as reference substrate for aspartate proteases, and exhibits a low activity towards N-acetyl-L-phenylalanyl-L-diiodotyrosine. Its specific clotting activity with χ-casein as substrate is only half of that of chymosin and pepsin A. [ABSTRACT FROM AUTHOR]

A new method is described for maximizing the yield of A-protein per liter of crude lysate. It involves a modified growth procedure for bacteriophage R17 which allows titers in excess of 1013 plaque forming traits per ml, and a new procedure for purifying the A-protein by acetic acid treatment of the whole phage. [ABSTRACT FROM AUTHOR]

Solubility of fluorene in benzene, chloroform, acetone, 1-propanol, isobutanol, and methylbenzene was experimentally measured at temperatures ranging from (283.00 to 323.00) K. The laser monitoring observation technique was used to determine the disappearance of the solid phase in a solid + liquid mixture. The results of these measurements were correlated with the Apelblat equation, which can be used as a useful model in the purification process of fluorene. [ABSTRACT FROM AUTHOR]

The article focuses on the use of Kromasil CelluCoat in the analysis and purification of chiral compounds. Kromasil CelluCoat refers to a silica based chiral stationary phases (CSP) coated with tris-carbamoyl cellulose as the chiral selector. The analysis involves a factor of selectivity that leads to enantiomer separation, which leads to the speed of separation.

The article present information about introduction of new polymeric reversed-phase columns, Amberchrom™ Profile™. These columns have been developed for the purification of peptides and oligonucleotides by reversed-phase chromatography. The columns have been able to achieve the purification target yield of eighty percent at more than ninety five percent purity in the purification of influenza peptide, that is used in the area of vaccine development..

Describes the use of the multiOPLC system, an Optimum Performance Laminar Chromatography system that incorporates the Flowing Eluent Wall Technology, to perform simultaneous semi-preparative scale separations of complex samples. Reagents and separation media; Instrumentation; Capability of the system to produce four independent channels on an unsegmented flat-bed column.

Demonstrates the utility of Atlantis dC[sub 18] columns via the separation and purification of three mixtures of polar compounds. Experimental conditions; Description of Atlantis dC[sub 18] reversed-phase columns; Retention and separation of the sulphonamides on the analytical column.

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