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An approach to the highly sensitive and selective determination of the bromine-containing antiviral drug umifenovir (Arbidol) and its metabolites in natural and waste water, activated sludge, and bottom sediments by chromatography-mass spectrometry based on a combination of two techniques- inductively coupled plasma mass spectrometry (ICP MS) and electrospray ionization high-resolution mass spectrometry (ESI HRMS) is developed. Reversed-phase chromatographic separation and detection based on ESI HRMS provide the reliable detection and identification of analytes in complex matrices, while the use of ICP-MS with .sup.79Br signal detection makes it possible to exclude matrix effects and use a single analytical standard for quantitative analysis. The use of solid-phase extraction and pressurized liquid extraction as sample preparation methods made it possible to achieve limits of detection at a level of 0.2 ng/L and 2 [micro]g/kg for liquid and solid samples, respectively. The developed approach was successfully tested in the analysis of real samples. It is shown that the concentrations of analytes in urban wastewaters are in the range 4.4-260 ng/L. The highest concentration (up to 3.7 mg/kg) is characteristic of activated sludge, which acts as an effective sorbent for umifenovir and its transformation products., Author(s): S. A. Sypalov [sup.1] , N. V. Ul'yanovskii [sup.1] , D. S. Kosyakov [sup.1] , A. T. Lebedev [sup.1] Author Affiliations: (1) grid.462706.1, 0000 0004 0497 5323, Core Facility [...]

A method of dispersive liquid-liquid microextraction, based on the dispersion of an extractant by the gas phase formed as a result of a phase transition, i.e., the evaporation of a highly volatile nonpolar organic solvent (dispersant) upon heating the extraction,-is developed. The analytical capabilities of the method are shown in the determination of preservatives (sorbic and benzoic acids) in soft drinks for baby food by high-performance liquid chromatography with photometric detection. The extractant and the dispersant for the microextraction of preservatives are chosen a terpenoid and a highly volatile organochlorine solvent, respectively, which excluded the use of polar organic solvents for dispersing phases, with which the distribution coefficients are reduced. The limits of detection (3[sigma]) for sorbic and benzoic acids are 0.3 mg/L. The developed method does not require centrifugation for phase separation., Author(s): M. A. Kochetkova [sup.1] , I. I. Timofeeva [sup.1] , A. V. Bulatov [sup.1] Author Affiliations: (1) grid.15447.33, 0000 0001 2289 6897, Institute of Chemistry, St. Petersburg State University, [...]

Specific features of chromatographic determination of xanthophyll esters are studied using an example of marigold flower lutein diesters under reversed-phase HPLC conditions. The developed two-column method made it possible to establish that, in samples with a low solubility of carotenoids in the used solvent and on a chromatography column in using a mobile phase with a low solubility of carotenoids, the precipitation of diesters is possible, which detrimentally affects the accuracy of the chromatographic determination. A critical factor in this case isì temperature: the storage of samples (solutions) in a refrigerator is not always advisable, because freezing of the main components is possible. It was shown that the use of a mobile phase containing from 0 to 10 vol % acetonitrile in acetone at a temperature not lower than 20°C is acceptable for the separation of all-trans-lutein diesters from cis-derivatives of lutein and zeaxanthin derivatives on 'monomeric' C18-phases., Author(s): V. I. Deineka [sup.1] , T. G. Burzhinskaya [sup.1] , I. P. Blinova [sup.1] , L. A. Deineka [sup.1] Author Affiliations: (1) grid.445984.0, 0000 0001 2224 0652, Institute of [...]

A simple trivalent silver complex ([Ag(HIO.sub.6).sub.2].sup.5-) and sulfuric acid chemiluminescence (CL) reaction is established for cetirizine dihydrochloride determination in dosage form pharmaceuticals using flow injection technique. The possible CL reaction mechanism and enhancing influence of cetirizine are described based on spectrophotometric, spectrofluorimetric and CL spectra. The optimum experimental variables of the CL reaction were: 1.0 x 10.sup.-4 M silver(III) complex, 5.0 x 10.sup.-3 M H.sub.2SO.sub.4, 1.0 x 10.sup.-3 M KOH, 5.0 mL/min flow rate and 180 [micro]L sample volume. The relative CL intensity was linear in the range of 0.1-20 mg/L (R.sup.2 = 0.9999, n = 7) with a limit of detection of 0.03 mg/L (S/N = 3), relative standard deviation of 1.6-3.4%, and injection frequency of 230/h. The suggested method has been successfully applied to monitor cetirizine concentration in various tablets and verified by the reported HPLC-UV approach that produces a recovery rate of 91.8-106%., Author(s): Muhammad Moazzam [sup.1] , Muhammad Asghar [sup.1] , Mohammad Yaqoob [sup.1] , Samar Ali [sup.1] , Masood Ahmad Siddiqui [sup.1] Author Affiliations: (1) grid.413062.2, 0000 0000 9152 1776, Department [...]

A simple and selective reversed-phase high performance liquid chromatography method was developed and validated for the quantification of 4-chloroaniline, 2-chloro-N-(4-chloro-2-(2-chlorobenzoyl)phenyl)acetamide and 2-iodo-N-(4-chloro-2-(2-chlorobenzoyl)phenyl)acetamide in lorazepam. 4âChloroaniline is used as a raw material and 2-chloro-N-(4-chloro-2-(2-chlorobenzoyl)phenyl)acetamide and 2-iodo-N-(4-chloro-2-(2-chlorobenzoyl)phenyl)acetamide are formed as intermediates in the synthesis of anxiety disorder active pharmaceutical ingredient lorazepam. This method provided excellent sensitivity and a typical target analyte level of 150 ppm. This method was developed on an Agilent poroshell 120 EC-C18 (100 x 4.6 mm, 4 [micro]m) column and a photo diode array detector. The proposed method is specific, linear, accurate and precise. The calibration curve was linear over the concentration range of LOQ to 120% with a correlation coefficient of 0.99. This method has low limits of detection and quantification for all the analytes. Accuracy was observed within the range of 85-115% for all the analytes. The developed method was validated as per the ICH guidelines in terms of specificity, precision, limit of detection, limit of quantification, linearity range and accuracy., Author(s): Panga Chinna [sup.1] [sup.2] , Shet Prakash M. [sup.1] , Ramesha Andagar Ramakrishna [sup.2] , Swamy Sreenivasa [sup.3] [sup.4] , Yashbir Singh [sup.2] Author Affiliations: (1) grid.412825.8, 0000 0004 [...]

Glycerol derivative triacetin (TA) has diverse applications in the pharmaceutical, fuel, cosmetic, and food industries. Hence, it is vital to quantify triacetin in a given sample before it can be employed for a suitable commercial application. The conventional HPLC based method of TA quantification is time-consuming, leads to generating liquid waste, and requires unique columns, reference materials, and a suitable detector for the identification of molecules under investigation. To simplify TA quantification, herein, we have proposed a quantitative proton nuclear magnetic resonance (qHNMR) based method which does not require any complicated sample preparation method, sample derivatization, long analysis time, or highly pure reference materials. For TA quantification, an equation based on proton NMR analysis of standard mixtures of TA and glycerol of variable compositions is proposed. To validate the developed method, TA was quantified in samples with its variable concentrations by either qHNMR or HPLC, and the results were found to be comparable (R.sup.2 = 0.99). Further, to demonstrate the practical application, the technique was employed to quantify TA formed during acetylation of glycerol with acetic acid at various time intervals., Author(s): Km Abida [sup.1] , Amjad Ali [sup.1] [sup.2] Author Affiliations: (1) grid.412436.6, 0000 0004 0500 6866, School of Chemistry and Biochemistry, Thapar Institute of Engineering and Technology, , 147004, [...]

The article deals with the development of a method for the determination of diflubenzuron in agricultural products using HPLC with a diode array detector. The samples were extracted with acetonitrile, and then purified by solid-phase extraction using C18E and PSA adsorbents and a Diapak C cartridge. The developed method was tested on the green mass of plants, potato tubers, corn grain, soybeans, sunflower seeds, rapeseed, and vegetable oil in the concentration range from 0.025 to 0.25 mg/kg. The average values of recovery were 81-91% with an error of 1.3-2.3%., Author(s): E. Yu. Alekseev [sup.1] , T. D. Chermenskaya [sup.1] Author Affiliations: (1) grid.465295.9, 0000 0001 0098 022X, All-Russian Research Institute of Plant Protection, , 196608, Pushkin, St. Petersburg, Russia [...]

Herein, comparative studies were conducted on different species of Pleurotus mushroom (Pleurotus osteratus, Pleurotus eryngii, Pleurotus sajor caju, Pleurotus florida, and Pleurotus roseus), extracted in two different solvent systems: dichloromethane (DCM)-ethanol (Et) with the ratio of 1 : 1 (v/v) and 50% (v/v) ethanol. Comparably, 50% (v/v) ethanolic crude extract had a considerably higher extraction yield and total phenolic, carbohydrate, and protein content. Owing to a high total phenolic yield, 50% (v/v) ethanolic crude extract had better ability to scavenge 2,2-diphenyl-1-picryl-hydrazyl-hydrate and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid radical. Contrarily, DCM-Et crude extract showed strong cytotoxic potential against the human breast cancer cell line (MD-MBA-231) and murine skin cancer cell line (B16F10). High-performance thin layer chromatography based methods were developed and validated as per the International Council for Harmonisation Q2(R1) for the determination of ergosterol. Ergosterol content in DCM-Et crude extract correlates with its cytotoxic potential., Author(s): Singh Shreya [sup.1] , Debadatta Mohapatra [sup.1] , Gaurav Gopal Naik [sup.1] , Yamini Bobde [sup.2] , Balaram Ghosh [sup.2] , Alakh N Sahu [sup.1] Author Affiliations: (1) grid.467228.d, [...]

Zinc oxide nanoparticles-chitosan assisted dispersive liquid-liquid microextraction (DLLME) was utilized to microextraction of ultra-traces of pyrene and phenanthrene from seawater samples of Chabahar Bay prior to HPLC analysis with UV detection. The analytes dispersed into organic phase with the assistance of zinc oxide nanoparticles-chitosan in the modified DLLME method. The effect of factors on extraction efficiency, including amount of zinc oxide nanoparticles-chitosan, amount of chitosan, amount of zinc oxide nanoparticles, type and volume of extraction and dispersive solvents, extraction time and rate, and time of centrifugation, was optimized and investigated. Under optimized conditions, good linearity ranges of 1.0-150 [micro]g/L for phenanthrene and 5-75 [micro]g/L for pyrene were achieved. Based on standard deviation to slope of calibration curve ratio of 3, the limits of detection were 0.4 and 1.7 [micro]g/L for phenanthrene and pyrene, respectively. Relative standard deviation was between 1.8-8.8%. The protocol was successfully utilized to the determination of pyrene and phenanthrene in seawater samples of Chabahar Bay. Relative recoveries from 79.0 to 105.0% were observed for the spiked seawater samples., Author(s): Morteza Ziyaadini [sup.1] , Sayyed Hossein Hashemi [sup.1] , Mir Mahdi Zahedi [sup.1] , Balall Raisi [sup.1] , Soheila Bashande [sup.1] Author Affiliations: (1) grid.459445.d, 0000 0004 0481 4546, [...]

Results of a study of water and water-alcohol extracts of wild chamomile (Matricaria chamomilla L.) depending on the conditions of their extraction by different methods are discussed. The test samples are wild chamomile samples collected in various regions of Russia. Phenolic components in their native forms were extracted from medicinal raw materials using infusion, maceration, microwave-assisted, ultrasound-assisted, and subcritical extraction, and by the pharmacopoeial method. Concentrations of individual components and total phenolic compounds in wild chamomile were determined by chromatographic methods. The HPLC determination of phenolic compounds with diode-array and mass spectrometric detection was carried out using gradient elution with a mixture of acetonitrile with 0.1% formic acid. Chlorogenic acid, ferulic acid glycosides, luteolin-7-O-glucoside, dicaffeoylquinic and chicoric acid, apigenin-7-glucoside, and apigenin were identified in water and water-alcohol extracts of wild chamomile. The dependence of the concentration of phenolic compounds on the geographical place of the growth of plant raw materials was studied based on value of this parameter in extracts of wild chamomile samples from different territories. The maximum total concentration of phenolic compounds (10.1 mg/g) was found in the extract of chamomile from FarmaTsvet (Krasnogorsk, Moscow oblast)., Author(s): Z. A. Temerdashev [sup.1] , T. K. Chubukina [sup.1] , E. A. Vinitskaya [sup.1] [sup.2] , N. V. Kiseleva [sup.1] Author Affiliations: (1) grid.26083.3f, 0000 0000 9000 3133, Kuban [...]

A new specific sorbent entitled molecularly imprinted polymer (Fe.sub.3O.sub.4@PDA MIP) was fabricated on the surface of ferroferric oxide nanoparticles with the dummy template of 5,7-dimethoxycoumarin through self-assembly of dopamine which is efficient for recognition and determination of aflatoxin B in food samples coupled with UPLC-FLD with a large volume flow cell. The prepared MIPs were characterized, and the adsorption properties were evaluated. The maximum adsorption capacities were 0.46 mg/g for aflatoxin B1 and 0.047 mg/g for aflatoxin B2. Under optimized conditions, the calibration plots are linear in the range of 0.005-0.5 and 0.001-0.1 ng/mL with LODs of 0.0024 and 0.0004 ng/mL for aflatoxin B1 and aflatoxin B2, respectively. The recoveries from spiked samples are 89.0-105.0% with RSDs of 5.6-7.7% in case of corn, peanut and edible oil. And after 7 cycles, the adsorption capacity of the MIPs did not decrease significantly., Author(s): Lili Suo [sup.1] , Meihua Hu [sup.2] Author Affiliations: (1) grid.507007.5, The collaboration Unit for Field Epidemiology of State Key Laboratory for Infectious Prevention and Control, Jiangxi Provincal Key [...]

A procedure is proposed for the extraction of 2,6-diisobornyl-4-methylphenol (IBP), the molecule with potential multi-target activity, and its active metabolite 2,6-diisobornyl-4-hydroxymethylphenol (IBP-OH) from human and rat plasma samples for further determination by liquid chromatography-tandem mass spectrometry. The solubility of IBP (in mg/mL) in various organic solvents is determined. In particular, the compound is readily soluble in chloroform (346 ± 14), methyl tert-butyl ether (98.6 ± 3.8), and ethyl acetate (96.8 ± 2.0). It is shown that the use of a mixture of chloroform and isopropanol (5 : 1, v/v) as an extraction system with simultaneous protein precipitation makes it possible to extract only 66 ± 10% of IBP, while the recovery of IBP-OH is 96 ± 7%. Pre-dilution of 200 [micro]L of plasma with 300 [micro]L saline increases IBP recovery to 100 ± 4%. Drying the extracts in a vacuum concentrator (air, 45°C) with the further reconstitution of the residues in 300 [mu]L of acetonitrile facilitates the purification of biosamples and the preconcentration of analytes. The total sample preparation time does not exceed 70 min, and the duration of an analysis is 7 min, the injection volume is 2 [micro]L. The procedure has been successfully tested on actual rat plasma samples after a single oral administration of IBP (10 mg/kg in oil) in the framework of pharmacokinetic studies., Author(s): A. P. Lakeev [sup.1] [sup.2] , E. A. Yanovskaya [sup.1] [sup.2] , V. A. Yanovsky [sup.1] , M. O. Andropov [sup.1] Author Affiliations: (1) grid.77602.34, 0000 0001 1088 3909, [...]

An automated method is developed for dispersive liquid-liquid microextraction of fluoroquinolone antibiotics based on the principles of stepwise injection analysis. The method involves the dispersion of the extractant by the gas phase, formed in situ in the extraction chamber of the flow analyzer. A deep eutectic solvent based on a terpenoid and a mixture of hydrophilic and hydrophobic carboxylic acids is studied as an extractant for the isolation and preconcentration of fluoroquinolones, and a possibility of its use is substantiated. Hydrophilic carboxylic acid in the composition of the extractant acts as a proton donor for the formation of a carbon dioxide dispersant in the presence of sodium carbonate dissolved in the aqueous phase. A possibility of combining the developed method with high-performance liquid chromatography with fluorimetric detection is shown on an example of the determination of fluoroquinolones in wastewaters. The limits of detection (3[sigma]) for ofloxacin, fleroxacin, and norfloxacin were 0.3 [micro]g/L., Author(s): I. I. Timofeeva [sup.1] , K. A. Barbayanov [sup.1] , A. V. Bulatov [sup.1] Author Affiliations: (1) grid.15447.33, 0000 0001 2289 6897, Department of Analytical Chemistry, Institute of Chemistry, [...]

The conditions for the chromatographic determination of ibuprofen in culture media of Rhodococcus spp. by reversed-phase HPLC are chosen. The specificity, linearity, and accuracy of the developed procedure are confirmed by the validation procedure, which allows its use for a reliable assessment of ibuprofen concentration in the process of bacterial degradation. With the use of kinetic modeling, a forecast is made for changes in the concentration of ibuprofen; the half-life period, the end time of the biodegradation process, and its reproducibility are determined., Author(s): E. V. Vikhareva [sup.1] [sup.2] , A. A. Selyaninov [sup.3] , G. A. Bazhutin [sup.1] , E. A. Tyumina [sup.1] Author Affiliations: (1) grid.426536.0, 0000 0004 1760 306X, Perm [...]

We present a critical review of experimental studies of the efficiency of the separation of various groups of chemical compounds under the conditions of high-performance liquid chromatography using metal-organic framework polymers (metal-organic frameworks (MOFs)) or composite materials with MOFs as a stationary phase. MOFs demonstrated many advantages in high-performance liquid chromatography and a possibility of competing successfully with conventional phases, especially in the determination of low-molecular-weight compounds and optical isomers. Among the promising options for using this class of materials are the development of monolithic separation columns and hybrid adsorbents that eliminate the disadvantages of adsorbents based on pure MOFs., Author(s): I. Kh. Shaikhutdinov [sup.1] , T. K. Ryazanova [sup.1] , L. V. Limareva [sup.1] , A. V. Sokolov [sup.1] Author Affiliations: (1) grid.445780.a, 0000 0001 0235 2817, Samara State [...]

The composition of fluids that mediate fertilization in cycads is described for the first time. Using tandem mass spectrometry, proteomes of two stages of fluid production, megagametophyte fluid and archegonial chamber fluid production, are compared in Cycas revoluta. These were compared with the proteome of another sexual fluid produced by ovules, the pollination drop proteins. Cycad ovules produce complex liquids immediately prior fertilization. Compared with the pollination drops that mainly had few proteins in classes involved in defense and carbohydrate modification, megagametophyte fluid and archegonial chamber fluid had larger proteomes with many more protein classes, e.g. proteins involved in programmed cell death. Using high-performance liquid chromatography, megagametophyte fluid and archegonial chamber fluid were shown to have elevated concentrations of smaller molecular weight molecules including glucose, pectin and glutamic acid. Compared to megagametophyte fluid, archegonial chamber fluid had elevated pH as well as higher osmolality. Keywords Amino acids * Carbohydrate * Cycad * Megagametophyte * Proteome * Sexual fluids, Introduction In gymnosperms, pollination and fertilization occur in distinctly separated stages that are mediated by fluids. During pollination, pollen is captured by young ovules; various pollen capture mechanisms occur that [...]

Accurate classification and understanding of metabolite variations in Eurycoma longifolia according to source, harvesting age, and planting location are of great importance to ensure the quality and standardization of E. longifolia-based products. In this study, an untargeted metabolomic approach using high-performance liquid chromatography coupled to quadrupole-time-of-flight mass spectrometry (HPLC-Q-ToF-MS) was used to classify E. longifolia samples and to determine metabolite variations in 1-, 4-, and 11-year-old E. longifolia roots collected from different planting locations. Principal component analysis (PCA) and hierarchical clustering analysis showed clear separation between hairy root culture and E. longifolia root samples, highlighting apparent metabolite differences between these samples. Moreover, the approach successfully separated E. longifolia root samples according to their harvesting age and planting location. The PCA loading plot after varimax rotation revealed that dominant ions with strong loadings to principal component 1 were identified as canthin-6-one alkaloid and quassinoid compounds. Overall, the findings indicate that HPLC-Q-ToF-MS-based metabolomics is a powerful approach to classify and determine metabolite variations in E. longifolia samples., Author(s): Nur Nabilah Alias [sup.1] , Norlia Basherudin [sup.1] , Nazirah Abdullah [sup.1] , Nor Hasnida Hassan [sup.1] , Kamalrul Azlan Azizan [sup.2] Author Affiliations: (1) grid.434305.5, 0000 0001 2231 [...]

A method is proposed for the HPLC separation of a mixture of carboxylic acids on a porous graphitized Hypercarb adsorbent under the conditions of gradient elution with formic acid solutions. The analytes were detected using a single quadrupole mass spectrometer. The stepwise gradient of formic acid without an addition of an organic solvent made it possible to achieve good resolution of the analyte peaks and decrease the limits of detection by a factor of 4.4-17.8 compared to their separation with 0.1% formic acid under isocratic conditions. The effect of methanol on the separation of analytes is less pronounced., Author(s): K. S. Gutenev [sup.1] , M. A. Statkus [sup.1] , G. I. Tsizin [sup.1] Author Affiliations: (1) grid.14476.30, 0000 0001 2342 9668, Department of Chemistry, Lomonosov Moscow State University, [...]

A highly efficient solid-phase extraction (SPE) column filled with a silica-based strong anion exchange sorbent was reported in the current study. The fabricated cartridge was used for the extraction and pre-concentration of folic acid in different standard and real samples prior to their chromatographic (HPLC-UV) investigation. Wide linear range (0.02â1.2 [micro]g/mL), low detection limit (0.006 [micro]g/mL), low quantification limit (0.02 [micro]g/mL), good relative standard deviation (2.6%), and good relative recoveries (96.0%) were attained under the optimum conditions. This cartridge was fabricated with accessible and inexpensive materials and can replace expensive commercial columns. In addition, simple synthesis steps, long service lifetime, and great extraction capability were some of the advantages of the proposed SPE column. The proposed technique was not affected by the interferences of sample matrices and can be successfully used for the routine determination of weak acidic substances including folic acid (at low levels)., Author(s): Zeinab Pourjabbar [sup.1], Yalda Pasandideh [sup.1], Afshin Rajabi Khorrami [sup.1] Author Affiliations: (1) grid.411769.c, 0000 0004 1756 1701, Department of Chemistry, Karaj Branch, Islamic Azad University, , Karaj, Iran [...]

Animal medicine (AM), as a kind of traditional Chinese medicine (TCM), has been used for thousands of years. However, sometimes AM can cause a variety of side effects similar to those caused by biogenic amines (BAs). So far, there has been no information about the type and content of BAs in AMs. Thus, an HPLC method with precolumn derivatization was developed for the characterization of ten kinds of BAs in seven commonly used AMs to provide referential data for the safety profile of AMs. The described method has good repeatability and reproducibility for the quantification of BAs in seven kinds of AMs. Among the ten selected BAs, histamine in Scolopendra was found to be 96 ± 4 mg/kg, exceeding the limit regulated by the US Food and Drug Administration. Although the levels of BAs in Scorpio, Hirudo, Bombyx Batryticatus, Gecko, Pheretima, and Eupolyphaga Steleophaga are below the amine toxicity level currently regulated and are safe to use individually, AMs are often used in combination with other TCMs containing BAs. This would lead to the overdose of toxic BAs. Therefore, it is necessary to propose limit standards for BAs in AMs and their polypharmacy to ensure their safety profiles and improve the quality standards., Author(s): Yanni Sun [sup.1], Yun Ai [sup.2], Fangyuan Yao [sup.1], Fei Mao [sup.1], Xinna Wang [sup.1], Yan Zhang [sup.1], Fengyi Guo [sup.1], Ying He [sup.1], Jianli Liu [sup.1], Ning Zhang [...]

This study used batch and online methods to accurately determine how much arsenic (As), chromium (Cr), selenium (Se), cadmium (Cd), lead (Pb), copper (Cu), iron (Fe), and zinc (Zn) can be leached from baby rice cereals into a baby's body. Speciation analysis of the saliva and gastric juice leachates was conducted to further assess the risk associated with the continued consumption of baby rice cereal for infants. A simple 15 min chromatographic analysis successfully separated eight species consisting of As(III), monomethylarsonic acid (MMA), dimethylarsinic acid (DMA), As(V), Se(IV), Se(VI), Cr(III), and Cr(VI). Given that 95%-100% As, 29%-100% Cr, 62%-100% Pb, 70%-100% Se, 63%-100% Cd, 36%-100% Cu, 67%-100% Fe, and 70%-100% Zn were bio-accessible and the speciation analysis results showed all bio-accessible As and Se to be in the forms of As(V) and Se(VI) and 70%-100% of Cr to be in the Cr(III) form, a variety of foods should be fed to infants rather than just baby rice cereal to ensure a well-balanced diet and less exposure to As at such a young age. Key words: speciation analysis, baby cereal, risk assessment, inductively coupled plasma mass spectrometry, bio-accessibility. Dans le cadre de la présente étude, nous avons utilisé des méthodes par lots et en ligne pour déterminer avec justesse les quantités d'As, de Cr, de Se, de Cd, de Pb, de Cu, de Fe et de Zn pouvant passer des céréales de riz pour bébés dans l'organisme d'un bébé. Nous avons soumis la salive et les lixiviats gastriques à une analyse de spéciation afin d'évaluer plus en détail le risque associé à la consommation continue de céréales de riz pour bébés. Une simple analyse chromatographique a permis de séparer en 15 minutes huit espèces, dont l'As(III), l'acide monométhylarsonique (MMA), l'acide diméthylar-sinique (DMA), l'As(V), le Se(IV), le Se(VI), le Cr(III) et le Cr(VI). Nos résultats montrent que 95 à 100% de l'As, 29 à 100% du Cr, 62 à 100% du Pb, 70 à 100% du Se, 63 à 100% du Cd, 36 à 100% du Cu, 67 à 100% du Fe et 70 à 100% du Zn étaient bioaccessibles, et ceux de l'analyse de spéciation, que tout l'As et le Se bioaccessibles se trouvaient sous forme d'As(V) et de Se(VI) et que 70 à 100% du Cr était sous forme de Cr(III). À la lumière de ces résultats, on peut conclure que l'alimentation des nourrissons, pour être équilibrée, devrait être composée d'aliments variés plutôt qu'uniquement de céréales de riz pour bébés, ce qui permettrait également de faire en sorte qu'ils soient moins exposés à l'arsenic à un si jeune âge. [Traduit par la Rédaction] Mots-clés : analyse de spéciation, céréales pour bébés, évaluation des risques, spectrométrie de masse à plasma à couplage inductif, bioaccessibilité., Introduction With an estimated 360 000 babies born a day worldwide, (1) the baby food industry is a fast growing market that provides a countless number of products to make [...]

As a new type of multifunctional material, metal-organic frameworks (MOFs) have a wide application prospect in the field of chiral separation. In this study, a homochiral MOF [Ni(S-mal)(bpy)].sub.n was synthesized by the reaction of S-malic acid (S-mal) and 4,4'-bipyridine (bpy) with nickel acetate. The homochiral MOF [Ni(S-mal)(bpy)].sub.n was explored as a new chiral stationary phase for HPLC separation of racemic compounds using n-hexane-isopropanol as a mobile phase. A series of racemic compounds were separated on this column. The results showed that the homochiral MOF column exhibited good chiral recognition ability toward six racemic compounds including amlodipine, ibuprofen, flurbiprofen, propranolol hydrochloride, chlorphenamine maleate and 1-p-chlorobenzyl-ethanol. The homochiral MOF column also offered good reproducibility and stability for the enantioseparation., Author(s): Nayan Xu [sup.1], Baoyan Yuan [sup.1], Cong Hu [sup.1], Yunyan Yu [sup.1], Nan Fu [sup.1], Junhui Zhang [sup.1], Shengming Xie [sup.1], Liming Yuan [sup.1] Author Affiliations: (1) grid.410739.8, 0000 [...]