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Mold deterioration of historical documents in archives and libraries is a frequent and complex phenomenon that may have important economic and cultural consequences. In addition, exposure to toxic fungal metabolites might produce health problems. In this work, samples of broths of fungal species isolated from the documentary material and from indoor environmental samples of the Archive of Bogotá have been analyzed to investigate the presence of mycotoxins. High resolution mass spectrometry made possible to search for a large number of mycotoxins, even without reference standards available at the laboratory. For this purpose, a screening strategy based on ultra-high pressure liquid chromatography coupled to quadrupole-time of flight mass spectrometry (UHPLC–QTOF MS) under MS E mode was applied. A customized home-made database containing elemental composition for around 600 mycotoxins was compiled. The presence of the (de)protonated molecule measured at its accurate mass was evaluated in the samples. When a peak was detected, collision induced dissociation fragments and characteristic isotopic ions were also evaluated and used for tentative identification, based on structure compatibility and comparison with literature data (if existing). Up to 44 mycotoxins were tentatively identified by UHPLC–QTOF MS. 34 of these tentative compounds were confirmed by subsequent analysis using a targeted LC–MS/MS method, supporting the strong potential of QTOF MS for identification/elucidation purposes. The presence of mycotoxins in these samples might help to reinforce safety measures for researchers and staff who work on reception, restoration and conservation of archival material, not only at the Archive of Bogotá but worldwide. [ABSTRACT FROM AUTHOR]

In this paper, a new and facile strategy has been demonstrated for the electrochemical determination of tryptophan (Trp), based on graphite-like carbon nitride (g-C 3 N 4 ) nanosheets modified glassy carbon (CNNS/GC) electrode. The g-C 3 N 4 nanosheets were obtained via exfoliating bulk graphitic carbon nitride (bg-C 3 N 4 ), which was synthesized using a thermal poly-condensation process. The obtained g-C 3 N 4 nanosheets were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), Fourier transform infrared (FTIR) spectroscopy and atomic force microscopy (AFM). The results confirmed graphite-like structure with thickness of about 6–8 nm. The as-synthesized g-C 3 N 4 nanosheets were closely attached to the surface of GC electrode to construct electrochemical sensor without needing any film-forming agents. The CNNS/GC electrode exhibited good electrocatalytic activity towards Trp, and hereby some parameters, including scan rate and pH effect on Trp determination were investigated. Under the optimum experimental conditions, the oxidation peak currents had good linear relationship with Trp concentrations in the range of 0.1–110 μM and a detection limit of 0.024 μM (S/N = 3) was achieved. In addition, the obtained sensor showed good sensitivity, favorable repeatability, and long-term stability. Finally, the proposed electrochemical sensor has been successfully applied for the determination of Trp concentration in real samples with satisfactory results. [ABSTRACT FROM AUTHOR]

Background Diet is a major source of human exposure to hazardous environmental chemicals, including many perfluoroalkyl acids (PFAAs). Several assessment methods of dietary exposure to PFAAs have been used previously, but there is a lack of comparisons between methods. Aim To assess human exposure to PFAAs through diet by different methods and compare the results. Methods We studied the dietary exposure to PFAAs in 61 Norwegian adults (74% women, average age: 42 years) using three methods: i) by measuring daily PFAA intakes through a 1-day duplicate diet study (separately in solid and liquid foods), ii) by estimating intake after combining food contamination with food consumption data, as assessed by 2-day weighted food diaries and iii) by a Food Frequency Questionnaire (FFQ). We used existing food contamination data mainly from samples purchased in Norway and if not available, data from food purchased in other European countries were used. Duplicate diet samples (n=122) were analysed by liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS) to quantify 15 PFAAs (11 perfluoroalkyl carboxylates and 4 perfluoroalkyl sulfonates). Differences and correlations between measured and estimated intakes were assessed. Results The most abundant PFAAs in the duplicate diet samples were PFOA, PFOS and PFHxS and the median total intakes were 5.6 ng/day, 11 ng/day and 0.78 ng/day, respectively. PFOS and PFOA concentrations were higher in solid than liquid samples. PFOS was the main contributor to the contamination in the solid samples (median concentration 14 pg/g food), while it was PFOA in the liquid samples (median concentrations: 0.72 pg/g food). High intakes of fats, oils, and eggs were statistically significantly related to high intakes of PFOS and PFOA from solid foods. High intake of milk and consumption of alcoholic beverages, as well as food in paper container were related to high PFOA intakes from liquid foods. PFOA intakes derived from food diary and FFQ were significantly higher than those derived from duplicate diet, but intakes of PFOS derived from food diary and FFQ were significantly lower than those derived from duplicate diet. We found a positive and statistically significant correlation between the PFOS intakes derived from duplicate diet with those using the food diary (rho=0.26, p-value=0.041), but not with the FFQ. Additionally, PFOA intakes derived by duplicate diet were significantly correlated with estimated intakes from liquid food derived from the food diary (rho=0.34, p=0.008) and estimated intakes from the FFQ (rho=0.25, p-value=0.055). Conclusions We provide evidence that a food diary or a FFQ-based method can provide comparable intake estimates to PFOS and PFOA intakes derived from a duplicate diet study. These less burdensome methods are valuable and reliable tools to assess dietary exposure to PFASs in human studies. [ABSTRACT FROM AUTHOR]

This paper reports the effect of storage temperature, storage time and glucose content on furanic derivatives (FDs) formation in fortified Madeira wines using headspace solid phase microextraction (HS–SPME) combined with gas chromatography-quadrupole mass spectrometry (GC–qMS), and microextraction by packed sorbent (MEPS) tandem with ultrahigh pressure liquid chromatography coupled to photodiode array detection (UPLC–PDA). Based on the results obtained, MEPS/UPLC–PDA showed better FDs extraction compared to HS–SPME/GC–qMS, in terms of analysis reduction, sensitivity, reproducibility and allow detect all target furanic derivatives considered in this study. 5-Hydroxymethyl-2-furfural, one of the most abundant FDs in wines, is not detected by HS–SPME/GC–qMS, which suggest that this methodology is not the most suitable to achieve the purpose of this study. Regarding the impact of storage time and temperature on FDs formation using MEPS/UPLC–PDA, it was verified an increase on FDs concentration during storage time independently of storage temperature as well as glucose content, and this increase is also favored by temperature increases, being more significant at 55 °C. The results obtained in this study could be used as a useful tool in winemaking field in order to introduce changes in fermentation as well as baking ( estufagem ) process, and/or predict the effects of storage time by application of high temperatures. [ABSTRACT FROM AUTHOR]

Background Congenital disorders of glycosylation (CDG) are inborn defects of glycan metabolism. They are multisystem disorders. Analysis of transferrin isoforms is applied as a screening test for CDG type I (CDG-I) and type II (CDG-II). We performed a retrospective cohort study to determine spectrum of phenotype and genotype and prevalence of the different subtypes of CDG-I and CDG-II. Material and methods All patients with CDG-I and CDG-II evaluated in our institution's Metabolic Genetics Clinics were included. Electronic and paper patient charts were reviewed. We set-up a high performance liquid chromatography transferrin isoelectric focusing (TIEF) method to measure transferrin isoforms in our Institution. We reviewed the literature for the rare CDG-I and CDG-II subtypes seen in our Institution. Results Fifteen patients were included: 9 with PMM2 -CDG and 6 with non- PMM2 -CDG (one ALG3 -CDG, one ALG9 -CDG, two ALG11 -CDG, one MPDU1 -CDG and one ATP6V0A2 -CDG). All patients with PMM2 -CDG and 5 patients with non- PMM2 -CDG showed abnormal TIEF suggestive of CDG-I or CDG-II pattern. In all patients, molecular diagnosis was confirmed either by single gene testing, targeted next generation sequencing for CDG genes, or by whole exome sequencing. Conclusion We report 15 new patients with CDG-I and CDG-II. Whole exome sequencing will likely identify more patients with normal TIEF and expand the phenotypic spectrum of CDG-I and CDG-II. [ABSTRACT FROM AUTHOR]

Abstract: Fabry disease is an X-linked lysosomal storage disorder caused by deficiency of alpha-galactosidase A, resulting in accumulation of the principal substrate, globotriaosylceramide (Gb3), in various physiological fluids and tissues in affected patients. The recognition that accumulation of Gb3 begins in utero, combined with the fact that the diagnosis of the disease is often delayed until after the development of irreversible tissue damage, has generated pressure to develop techniques for the early, pre-symptomatic diagnosis of the disease. Measurements of urinary Gb3 have been shown to be useful for the diagnosis of Fabry disease in adults. The objective of this work was to measure the Gb3/creatinine biomarker in urine of healthy infants from birth to 6months, including the establishment of reference ranges for urinary Gb3 excretion at various postnatal ages, in male and female infants. We employed liquid chromatography–tandem mass spectrometry (LC–MS/MS) to determine Gb3/creatinine ratios in urine specimens dried on filter paper and mailed to the laboratory by participating parents. A total of 728 urine specimens were obtained at intervals from birth to 6months of age from 68 healthy infants (35 male and 33 female). Parental participation was good, with 90% of the expected specimens received by the laboratory. The results of the analyses were grouped by the age of the infants into four periods. We have determined that both postnatal age and sex have an effect on urinary Gb3 excretion levels which vary considerably in newborns. We conclude that screening for Fabry disease by measurement of urinary Gb3 excretion is unlikely to be reliable before 30days of age. [Copyright &y& Elsevier]

4-Epi-oxytetracycline (4-EOTC), one of main oxytetracycline (OTC) metabolites, can be commonly detected in food and environment. The toxicity and effects of OTC on animals have been well characterized; however, its metabolites have never been studied systemically. This study aims to investigate 15-day oral dose toxicity and urine metabonomics changes of 4-EOTC after repeated administration in Wistar rats at daily doses of 0.5, 5.0 and 50.0 mg/kg bw (bodyweight). Hematology and clinical chemistry parameters, including white blood cell count, red blood cell count, total protein, globulin and albumin/globulin, were obviously altered in rats of 5.0 and 50.0 mg/kg bw. Histopathology changes of kidney and liver tissues were also observed in high-dose groups. Urinary metabolites from all groups were analyzed using ultra-high performance liquid chromatography coupled to quadrupole time-of-flight mass spectrometry (UPLC-Q-TOF/MS). Seventeen metabolites contributing to the clusters were identified as potential biomarkers from multivariate analysis, including aminoadipic acid, 6-phosphogluconate, sebacic acid, pipecolic acid, etc. The significant changes of these biomarkers demonstrated metabonomic variations in treated rats, especially lysine and purine metabolism. For the first time in this paper, we combined the results of toxicity and metabonomics induced by 4-EOTC for the serious reconsideration of the safety and potential risks of antibiotics and its degradation metabolites. [ABSTRACT FROM AUTHOR]

Abstract: The paper presents the application of liquid chromatography coupled with evaporative light scattering detector (LC-ELSD) for the determination of biogenic amines in different cheese samples, as their presence and relative amounts give useful information about freshness, level of ripening and quality of storage. Forty samples from different types of milk – hard-ripened, ripened and unripened – were considered. Results showed that the amine contents varied in relation to the manufacturing process, the highest concentration being in hard-ripened cheeses followed by ripened and then unripened. In hard-ripened cheeses amines were β-phenylethylamine (PHE) (69.8–136.6mgkg−1), tyramine (TYR) (19.7–147.1mgkg−1), spermidine (SPD) (nd–73.1mgkg−1), cadaverine (CAD) (nd–64.7mgkg−1), histamine (HIS) (17.6–48.2mgkg−1), spermine (SPM) (nd–47.4mgkg−1), putrescine (PUT) (nd–44.1mgkg−1) and agmatine (AGM) (nd–4.2mgkg−1); while in ripened cheese TYR (nd–116.7mgkg−1), PUT (nd–82.9mgkg−1), HIS (nd–57.7mgkg−1), PHE (nd–51.1mgkg−1), SPD (nd–31.5mgkg−1), CAD (nd–30.7mgkg−1), SPM (nd–26.9mgkg−1) and AGM (nd–4.8mgkg−1). On the basis of literature limits, in this study only hard ripened cheeses could represent a possible risk for consumers as they exceeded a proposed limit for PHE and total biogenic amines amount. [Copyright &y& Elsevier]

Abstract: An LC-ESI-MS/MS method was developed for the quantitative detection of postharvest fungicide residues in citrus juices and reported in this paper. The analyses of thiabendazole (TBZ), carbendazim (MBC), thiophanate methyl (TPM), imazalil (IMZ) and prochloraz (PCZ) residues were performed by using a gradient elution in conjunction with positive ionization mode electrospray ionization tandem mass spectrometry. Fungicides were extracted from citrus juices with recoveries ranging from 79.8 to 101.2% and relative standard deviation better than 15%. The quantification limits ranged from 0.01 μg/kg IMZ to 0.06 μg/kg for MBC. The LC-MS-MS method was applied to commercial citrus juices, detecting MBC, TBZ and IMZ residues in the 90% of the samples. Prochloraz residues were detected only in one of the multifruit juice (orange, lemon and carrot) samples. [Copyright &y& Elsevier]

Abstract: This paper presents the results of an evaluation of chloramphenicol (CAP) levels in eight samples of propolis extracts considered to be the best-known brands of propolis specialities produced in Italy. The aim was to verify whether determination of CAP residues might be useful and appropriate in propolis derivatives in addition to other matrices previously studied. Hydroalcoholic and glycolic extract were simply diluted with ethyl acetate, and CAP was determined by monitoring the selective transition of two parent ions. These commercial products were analysed using liquid chromatography–tandem mass spectrometry method. Thiamphenicol as internal standard was used for quanitification. Detection of the analyte was achieved by negative ionization electrospray in the selected reaction monitoring (SRM) mode. For confirmation, two characteristic mass transitions were monitored, both for the analyte and the internal standard. [Copyright &y& Elsevier]

Abstract: The cyclic 1,N 2-propanodeoxyguanosine (PdG) adducts are Michael addition products from reactions of deoxyguanosine (dG) with enals, including acrolein (Acr), crotonaldehyde (Cro), pentenal (Pen), heptenal (Hep), and 4-hydroxy-2-nonenal (HNE). Although this is a general reaction, only the PdG adducts derived from Acr, Cro, and HNE have been detected in vivo as endogenous DNA lesions. Our previous in vitro study demonstrated that PdG adducts of Acr, Cro, and Pen are predominantly derived from oxidation of ω-3 polyunsaturated fatty acids (PUFAs), whereas the long-chain Hep and HNE adducts are from ω-6 PUFAs. PdG adducts are important because they represent a new class of endogenous promutagenic DNA lesions with potential roles in carcinogenesis. Earlier, we developed a 32P-postlabeling method for detecting PdG adducts from Acr and Cro and a modified method for the long-chain HNE adducts. Both methods require multiple high-performance liquid chromatography steps and, in some cases, time-consuming thin-layer chromatography for purification. There is a lack of a single, versatile, and efficient method for simultaneous detection of all five enal-derived PdG adducts. In this paper, we report an improved 32P-postlabeling method which permits detection of Acr, Cro, Pen, Hep, and HNE adducts in a single DNA sample. This method relies on solid-phase extraction for adduct enrichment before and after 32P-labeling; all five PdG adducts were converted to the ring-opened derivatives for confirmation of identities and quantification. The method was validated using the synthetic adducts and enal-modified DNA and was finally applied to rat liver DNA and rat liver DNA samples spiked with different amount of standards. The detection limit was determined to be as low as 0.5fmol in 80μg DNA, corresponding to 9 adducts/109 dG. [Copyright &y& Elsevier]

The conventional method of assaying for the ubiquinone (CoQ) content of biological samples is to partition CoQ into an organic phase and separate it from contaminants by high-performance liquid chromatography (HPLC). HPLC is an accurate method of quantifying CoQ content but is not ideal for routine clinical analyses. This paper describes the development of a rapid method for assaying the CoQ content of biological samples based on the binding of CoQ to a CoQ binding peptide. The 14-amino acid binding peptide was chemically synthesized, and conditions for immobilizing the peptide on microfuge tubes were established. CoQ could be selectively bound to the immobilized peptide, eluted, and determined spectrophotometrically. Limits of detection for the method were 0.25 to 5 nmol CoQ. To test biological samples, CoQ was isolated from cultures of Saccharomyces cerevisiae grown in oleic acid medium. The recovery of CoQ samples using the binding assay ranged from 99 to 102% of the values obtained with HPLC. The assay described here provides an inexpensive, rapid method for determining the CoQ content of large numbers of biological samples in a variety of laboratory settings. [Copyright &y& Elsevier]

SYBR Green 1 is an asymmetrical cyanine DNA-binding dye that provides an opportunity for increasing the sensitivity of nucleic acid detection when used in conjunction with gel electrophoresis. In this paper, we summarize the general properties and specific uses of SYBR green 1 in ion-pair reversed-phase denaturing high-performance liquid chromatography (IP DHPLC). We describe several applications for the WAVE DHPLC platform that illustrate the generic potential of such intercalating dyes in mutation detection and gene expression profiling. We show that SYBR Green 1 obviates the need to use end-labeled oligodeoxynucleotides for the sensitive detection of nucleic acids during chromatography. Moreover the incorporation of SYBR Green 1 into samples and elution buffers does not impair resolution and has no significant effect on the retention times of DNA fragments compared with dye-free DHPLC. [Copyright &y& Elsevier]

This paper describes a rapid and simple technique for the simultaneous quantitative analysis of PGE2, PGE3, and other closely related prostaglandins from cultured cells using liquid chromatography/electrospray ionization tandem mass spectrometry. This method permits quantification of selected individual prostaglandins derived either from arachidonic acid (AA) or eicosapentaenoic acid (EPA) from cell extracts without tedious derivatization, lengthy sample preparation, and separation required by GC-MS- or HPLC-UV-based methods. The validation assessment showed that the quantitative determination is linear (r2>0.999) for both PGE2 and PGE3 in the range tested (1–500 ng/ml, 0.0028–1.4 μM) and a coefficient of variation lower than 10% was obtained for samples analyzed on 3 separate days. The detection limit was 2.5 pg for both PGE2 and PGE3. Extraction efficiency of PGE2 and PGE3 from cell suspensions ranged from 89.4 to 98.2%. As an application of the method, prostaglandins formed by EPA in human lung cancer A549 cells were determined. A 62% reduction of PGE2 formation was noted when A549 cells were treated with 100 μM of EPA. Concomitantly, EPA increased formation of PGE3 by 10-fold in A549 cells. This is the first report that unequivocally demonstrates that EPA can be converted to PGE3 by cyclooxygenase in human cancer cells. [Copyright &y& Elsevier]

In this paper, a reverse-phase high-performance liquid chromatographic method using a chemically modified electrode coupled with microdialysis was developed to study the effect of electromagnetic impulse (EMI) on monoamine neurotransmitter metabolism in nerve cells. To detect the monoamines and their metabolites, a poly (para-aminobenzoic acid) (P-pABA)-modified electrode was prepared. The modified electrode exhibited efficiently electrocatalytic oxidation for monoamines and their metabolites with relatively high sensitivity, stability, and long life. Nerve cells were primarily cultured. EMI was radiated to three experimental model nerve cells: (i) on mature nerve cells, (ii) on the culture medium, and (iii) on juvenile nerve cells for various periods of time. Then the levels of monoamines in the culture medium were detected by high-performance liquid chromatography–electrochemical detection. The data indicated that electromagnetic fields could influence neurotransmitter metabolism by direct effect on nerve cells or effect on the nutrient medium and that the effect was not only relevant with the length of radiation time, but also with the growing state of the nerve cells. [Copyright &y& Elsevier]

We have previously reported that sugar-mapping by liquid chromatography/mass spectrometry (LC/MS) equipped with a graphitized carbon column (GCC) can be useful for structural analysis of carbohydrates in a glycoprotein. In this paper, we evaluated sugar-mapping with regard to its use in comparability assessment of glycoprotein products. Erythropoietins (EPO) produced from three different sources were chosen as models of the closely related glycoprotein products. The two-dimensional displays of sugar maps drawn by LC/MS with GCC clearly showed the differences in carbohydrate heterogeneity with regard to sialylation, acetylation, and sulphation patterns among three EPOs. Exoglycosidase digestion followed by sugar-mapping provided information regarding the structure of characteristic carbohydrates in each EPO. These results demonstrate that LC/MS with GCC can reveal the details of carbohydrate heterogeneity in order to distinguish between closely related glycoprotein products. Our method can thus be useful in comparability assessments of therapeutic glycoproteins. Copyright 2002 The International Association for Biologicals. Published by Elsevier Science Ltd. All rights reserved. [Copyright &y& Elsevier]

As laid down by the Codex Alimentarius, products bearing a gluten-free label must not contain gluten levels above 20 mg/kg to be safe for consumption by celiac disease patients. Analytical methods to detect gluten from wheat, rye and barley need to be sufficiently sensitive, specific, suitable for routine analyses and validated by collaborative studies. With continuous progress in the field of gluten analysis, the aim of this paper is to provide an up-to-date overview of legislation regarding gluten-free products worldwide, as well as immunochemical, proteomics-based, genomics-based and other methods designed to analyse gluten traces. While ELISA test kits and PCR are still most widely used in quality control, liquid chromatography tandem mass spectrometry (LC-MS/MS) is gaining more and more importance by providing unprecedented insights into gluten. Several other methods such as immunosensors, other sensors and microarrays are being developed. The pro's and con's of the different methods are discussed as well as the remaining challenges, including the need for improved extraction procedures, comprehensive reference materials and independent reference methods. Image 1 • Gluten from wheat, rye and barley is known to cause celiac disease. • Gluten-free products must contain gluten levels below 20 mg/kg. • ELISA and PCR are commonly used to detect gluten in routine analyses. • Proteomics LC-MS/MS methods provide unprecedented insights into gluten complexity. • Reference materials for gluten and improved extraction methods are still needed. [ABSTRACT FROM AUTHOR]

Abstract: Utilizing combined liquid chromatography–tandem mass spectrometry (LC–MS/MS) as the analytical method, we have demonstrated a ten to sixtyfold excess of lysophosphatidyl choline containing hexacosanoic acid (26:0) in dried blood spots on a filter paper matrix from 25 male patients with X-linked adrenoleukodystrophy and nine patients with peroxisome biogenesis disorders compared to 19 controls. There was no overlap between normal subjects versus affected subjects. [Copyright &y& Elsevier]

• First application of microwave assisted extraction for antineoplastic drugs. • First time antineoplastic compounds are extracted from marine fish. • Three different species were analysed of different trophic chain levels. • Two antineoplastic compounds were extracted with good recoveries. Presence of antineoplastic compounds in the marine environment could cause adverse effects even at very low concentrations. The bulk of the produced literature at present has focused on the detection of these compounds in wastewater samples, while only a few papers tackled the more complex solid samples and until now, to the best of our knowledge, none has investigated marine organisms. This work presents the development, optimisation and application of an analytical method for the extraction and determination of the four antineoplastic compounds; cyclophosphamide, vincristine, vinblastine and tamoxifen, from fish tissues by microwave assisted extraction and ultra-high-performance liquid chromatography coupled to tandem mass spectrometry. Under optimal conditions, recoveries ranged between 60% and 120%, while intra- and inter-day precision were in the 5.0–19.4% and 12.0–20.4% ranges, respectively. Method detection and quantification limits were in the ranges 0.8–1.3 and 2.7-4.3 ng·g−1 dry weight for tamoxifen and cyclophosphamide, and 46.3–536 and 154-1787 ng·g−1 dry weight for vinblastine and vincristine, respectively. The developed analytical method was successfully applied for the extraction and determination of target compounds from muscle and liver tissues belonging to three different fish species. The results did not highlight any contamination by target antineoplastic molecules in the investigated fish tissues. [ABSTRACT FROM AUTHOR]