The effectiveness of a novel binary matrix composed of 1,8-bis(dimethylamino)naphthalene (DMAN;proton sponge) and 9-aminoacridine (9AA) for the direct lipid analysis of whole bacterial cells by matrixassisted laser desorption ionization mass spectrometry (MALDI MS) is demonstrated. Deprotonated ana-lyte signals nearly free of matrix-related ions were observed in negative ion mode. The effect of themost important factors (laser energy, pulse voltage, DMAN/9AA ratio, analyte/matrix ratio) was investi-gated using a Box–Behnken response surface design followed by multi-response optimization in order tosimultaneously maximize signal-to-noise (S/N) ratio and resolution. The chemical surface compositionof single or mixed matrices was explored by X-ray photoelectron spectroscopy (XPS). Moreover, XPSimaging was used to map the spatial distribution of a model phospholipid in single or binary matrices.The DMAN/9AA binary matrix was then successfully applied to the analysis of intact Gram positive(Lactobacillus sanfranciscensis) or Gram negative (Escherichia coli) microorganisms. About fifty majormembrane components (free fatty acids, mono-, di- and tri-glycerides, phospholipids, glycolipids andcardiolipins) were quickly and easily detected over a mass range spanning from ca. 200 to ca. 1600 m/z.Moreover, mass spectra with improved S/N ratio (compared to single matrices), reduced chemical noiseand no formation of matrix-clusters were invariably obtained demonstrating the potential of this binarymatrix to improve sensitivity.

Nowadays, matrix-assisted laser desorption/ionization (MALDI) time-of-flight mass spectrometry represents an emerging and versatile tool for analysis of lipids. However, direct (i.e., with no previous separation of lipid classes) analysis of crude extracts containing a complex mixture of lipids (a problem typically encountered in shotgun lipidomics) is still a quite challenging task using a conventional MALDI matrix such as 2,5-dihydroxybenzoic acid (DHB). Indeed, in the presence of phospholipids containing quaternary ammonium groups, such as phosphatidylcholines and sphingomyelins, strong ionization-suppression effects are experienced especially in positive ion mode. To overcome this limitation, lumazine (1H-pteridine-2,4-dione) was evaluated as an alternative matrix. Lumazine in the solid state showed an absorption maximum at 350 nm, ionizes/desorbs without appreciable decomposition and extensive cluster formation, and can be used in both ion modes. In positive ion mode, the main species were M(center dot+) and 2M(center dot+) radical cations and cationized species ([M+H](+), [M+Na](+), [M+2Na+2Li-3H](+)). In negative ion mode, the main signals observed were the deprotonated molecular ion and the radical anion. The signal-to-noise ratio for phosphatidylglycerols and phosphatidylethanol-amines using lumazine was almost 1 order of magnitude higher than that observed for DHB. Lumazine was successfully used for MALDI analysis (positive and negative ion modes) of crude lipid extracts of milk, soymilk, and hen egg, where phosphatidylethanolamines, phosphatidylserines, and phosphatidylinositols could additionally be detected.

Head space(HS)solid-phasemicro extraction(SPME)combinedwith gaschromatography–mass spectrometry (GC–MS) was used to analyze the volatile fraction of ambers of different geological origin. In particular, Romanian (romanite)and Baltic (succinite)amber samples were studied.Both types of amber have nearly similar bulk chemical compositions and could probably reflect only some differences of paleo biological and/or diagenetic origin. The present study shows that amber headspace fingerprint, obtained bySPME/GC–MS, can provide a simple and quasi non-destructive method capable of romanite/succinite differentiation. Among the numerous compounds present in the headspace,a number of few informative variables could be selected that were able to differentiate the ambers as demonstrated by Principal Component and Cluster Analysis.

A simple protocol, based on Bligh–Dyer (BD) extraction followed by MALDI-TOF-MS analysis, for fast identification of paint binders in single microsamples is proposed. For the first time it is demonstrated that the BD method is effective for the simultaneous extraction of lipids and proteins from complex, and atypical matrices, such as pigmented paint layers. The protocol makes use of an alternative denaturing anionic detergent (RapiGestTM) in order to improve efficiency of protein digestion and purification step. Detection of various lipid classes, such as triacylglycerols (TAGs) and phospholipids (PLs), and their oxidation by-products was accomplished, whereas proteins could be identified by peptide mass fingerprinting. The effect of pigments on ageing of lipids and proteins was also investigated. Finally, the proposed protocol was successfully applied to the study of a late-15th century Italian panel painting allowing the identification of various proteinaceous and lipid sections in organic binders, such as egg yolk, egg white, animal glue, casein, and drying oil. ©

A simple software, to be used as an aid in the identification of non-tryptic peptides based on low resolution (3D-ion trap) tandem (MS/MS) and sequential (MS3) mass spectrometry data, is presented. The program, named INSPIRE (Identification of Non-tryptic peptide Sequences based on Product Ions m/z ratios and RElative abundances), provides alternative rankings for the several candidate sequences usually arising from protein database searches when non-tryptic peptides are involved and only low resolution MS/MS data are available. The rankings, based on parameters related to m/z ratios and relative abundances of experimental product ions matching with predicted ones, can be exploited to reduce the number of candidates to be included in subsequent data processing based on MS3 measurements. The latter usually represents a mandatory step towards a reliable peptide identification when high resolution MS/MS data are not accessible. Sets of peptide sequences arising from MS/MS-based database searches for 63 previously identified non-tryptic peptides (all generated from milk proteins) were exploited to check the INSPIRE performance. It was found that, if retrieved among candidates after the database search, the correct sequence was always ranked among the first 10 ones when parameters calculated by INSPIRE were adopted for discrimination purposes. Under the same conditions the ranks provided by popular database search programs were significantly worse in a remarkable number of cases.

The aim of the present study was to provide experimental evidence that base pairing, commonly occurring between nucleic bases in more complex supramolecular arrangements, may affect the reaction pathways associated with the alkylation of bases themselves. In pursuit of this aim, dilute aqueous solutions of Cytidine- (CMP) and Guanosine-Mono-Phosphate (GMP) as single reactants or in an equimolar mixture were treated with the electrophilic alkylating agent 1,2- Dodecyl-Epoxide (DE), which was preventively dispersed into micellar solutions prepared with the cationic surfactant hexadecyltrimethylammonium bromide (CTAB). In the early stage of the reaction, CTAB micelles acted as micro-heterogeneous nanoreactors, but as the reaction progresses the systems evolved toward the formation of polydisperse aggregates, whose size and surface-charge properties were monitored as a function of reaction time. From mass spectrometry analyses, it was found that the deamination of cytosine, a side reaction related to the alkylation of the amino group of CMP, was reduced when both the complementary ribonucleotides were present in the same reaction mixture. The involvement of specific sites able to establish C:G interactions (possibly via H-bonding or p–p stacking) could explain the reduced reactivity occurring at the level of some of the nucleophilic centers responsible for molecular recognition.

A boronic analogue of the archetype matrix a-cyano-4-hydroxycinnamic acid (CHCA) has been synthesised providing a new ‘‘reactive matrix’’ that possesses molecular recognition properties. This matrix selectively recognizes vic-diols, a-hydroxyacids, aminols and first allowed the detection of anions as fluoride (unaffordable by usual matrices).

Pyrolysis gas chromatography–mass spectrometry (PyGC-MS) was used as a rapid method for the characterization of permanent marker ink. Twenty-four samples of various colours purchased from different manufacturers were characterised. Four main typologies of polymer-binding medium could be distinguished on the basis of the pyrolysis products, and differentiation between permanent markers of different manufacturers could be accomplished. For some permanent marker samples, PyGC-MS analysis allowed pigment identification as well.

The Maillard-reaction-induced lactosylation of the major whey proteins, alpha-lactalbumin (alpha-La) and beta-lactoglobulins (beta-Lg) A and B, occurring upon heating at 70, 80 and 90 degrees C for 1 to 5 h in the presence of lactose excess, was studied by HPLC coupled to electrospray ionization single and tandem mass spectrometry (HPLC-ESI-MS, MS/MS). The presence of significant amounts of mono and bi-lactosylated forms of the three proteins and their increase with heating temperature and time were assessed from MS data. Evidences for a concomitant, significant denaturation, involving partial tertiary structure unfolding, were also obtained in the case of beta-lactoglobulins. A subsequent ESI-MS and MS/MS investigation on the tryptic digests of heated protein solutions exhibiting high percentages of mono and bi-lactosylated forms provided information on lactosylation sites. In particular, the latter were identified both on tryptic and on aspecific peptides, whose unusual relevance (compared to similar studies) was found to be due mainly to heat-induced protein degradation, occurring before protein digestion with trypsin. Among lactosylation sites identified only on tryptic peptides, i.e., those reasonably related to intact protein lactosylation, two lysines residues were found for alpha-La, both located in accessible regions of its tertiary structure. In the case of beta-Lg, besides three sites common to variants A and B (leucine 1, lysines 70, and 75), lysine 69 was found to be lactosylated only in variant B. Its proximity to a critical region of beta-Lg tertiary structure suggests that the difference between the two variants could be ascribed to a different evolution of their conformation upon heating.

The present work is aimed at developing gold nanostructures functionalized with antenna systems to exploit the synergistic nanostructure/antenna desorption-ionization efficiency. A potential Matrix- Assisted Laser Desorption Ionisation (MALDI) organic matrix has been modified introducing specific functional groups or molecular linker and used as a capping agent for gold nanostructures. In particular, conjugated naphthyl-thio-derivative, i.e. 4-mercaptonaphthalene-1,8-dicarboxylic acid, was synthesized and characterized by means of nuclear magnetic resonance, UVevisible and X-ray photoelectron spectroscopies. Afterwards, the thio-derivative was used as covalent surface modifier for flat gold surfaces and nanostructured gold films. These surfaces were thoroughly characterized by means of parallel angle-resolved X-ray photoelectron spectroscopy to obtain quantitative information about elemental composition, chemical speciation, and in-depth distribution of the target chemical functional groups. Finally the compound was preliminarily tested as a non-conventional matrix in Laser Desorption Ionisation Mass Spectrometry (LDI-MS) analysis of low molecular weight biomolecules in order to assess its capability of acting as the antenna system and proton donor after covalent bonding to gold nanomaterials.

An unprecedented characterization of free fatty acids (FFA) in the lipid extracts of fresh or thermally treated mussels of sp. Mytilus galloprovincialis, including up to 128 saturated, mono- or poly-unsaturated and 63 oxidized (i.e., modified by hydroxylic, carbonylic and/or epoxylic groups) compounds, was achieved using reverse phase chromatography coupled to electrospray ionization-Fourier transform single and tandem mass spectrometry (RPC-ESI-FTMS,MS/MS). Subsequent Principal Components Analysis (PCA) evidenced several effects of thermal treatments on the mussel FFA profiles. In particular, death-inducing low temperature treatments (freezing at -16 °C or refrigeration at 4 °C for several days) induced a peculiar increase in the incidence of FFA, whereas the effect was absent in mussels undergoing death upon prolonged storage at room temperature (25 °C, 6 h) or fast cooking (100 °C, 5 min). Alive mussels, either fresh or resulting from short term (up to 48 h) refrigeration were actually indistinguishable by PCA, although subtle seasonal effects were observed.

A matrix-assisted laser desorption ionization time-of-flight mass spectrometry-based approach was applied for the detection of various lipid classes, such as triacylglycerols (TAGs) and phospholipids (PLs), and their oxidation by-products in extracts of small (50–100 μg) samples obtained from painted artworks. Ageing of test specimens under various conditions, including the presence of different pigments, was preliminarily investigated. During ageing, the TAGs and PLs content decreased, whereas the amount of diglycerides, short-chain oxidative products arising from TAGs and PLs, and oxidized TAGs and PLs components increased. The examination of a series of model paint samples gave a clear indication that specific ions produced by oxidative cleavage of PLs and/or TAGs may be used as markers for egg and drying oil-based binders. Their elemental composition and hypothetical structure are also tentatively proposed. Moreover, the simultaneous presence of egg and oil binders can be easily and unambiguously ascertained through the simultaneous occurrence of the relevant specific markers. The potential of the proposed approach was demonstrated for the first time by the analysis of real samples from a polyptych of Bartolomeo Vivarini (fifteenth century) and a “French school” canvas painting (seventeenth century).

Nanomaterials have emerging importance in laser desorption ionization mass spectrometry (LDI–MS) with the ultimate objective being to overcome some of the most important limitations intrinsically related to the use of conventional organic matrices in matrix-assisted (MA) LDI–MS. This review provides a critical overview of the most recent literature on the use of gold nanomaterials as non-conventional desorption ionization promoters in LDI– MS, with particular emphasis on bioanalytical applications. Old seminal papers will also be discussed to provide a timeline of the most significant achievements in the field. Future prospects and research needs are also briefly discussed.

Nanomaterials have emerging importance in laser desorption ionization mass spectrometry (LDI–MS) with the ultimate objective being to overcome some of the most important limitations intrinsically related to the use of conventional organic matrices in matrix-assisted (MA) LDI–MS. This review provides a critical overview of the most recent literature on the use of gold nanomaterials as non-conventional desorption ionization promoters in LDI– MS, with particular emphasis on bioanalytical applications. Old seminal papers will also be discussed to provide a timeline of the most significant achievements in the field. Future prospects and research needs are also briefly discussed.

A mixture of native and oxidized phospholipids (PLs), generated by the soybean lipoxygenase type V-catalyzed partial oxidation of a lipid extract obtained from human platelets, was analyzed by HydrophilicInteraction Liquid Chromatography-ElectroSpray Ionization-Tandem Mass Spectrometry (HILIC–ESI-MS/MS). The complexity of the resulting mixture was remarkable, considering that the starting lipid extract, containing (as demonstrated in a previous study) about 130 native PLs, was enriched with enzy-matically generated hydroperoxylated derivatives and chemically generated hydroxylated forms of PLsbearing polyunsaturated side chains. Nonetheless, the described analytical approach proved to be verypowerful; indeed, focusing on phosphatidylcolines (PCs), the most abundant PL class in human platelets,about fifty different native/oxidized species could be identified in a single HILIC–ESI-MS/MS run. Low-energy collision induced dissociation tandem MS (CID-MS/MS) experiments on chromatographicallyseparated species showed single neutral losses of H2O2 and H2O to be typical fragmentation pathways of hydroperoxylated PCs, whereas a single H2O loss was observed for hydroxylated ones. Moreover, diag-nostic losses of n-hexanal or n-pentanol were exploited to recognize PCs hydroperoxylated on the last butfive carbon atom of a -6 polyunsaturated side chain. Despite the low resolution of the 3D ion trap mass analyzer used, the described HILIC–ESI-MS/MS approach appears very promising for the identification ofoxidized lipids in oxidatively stressed complex biological systems.

A method based on capillary liquid chromatography combined with electrospray ionization-tandem mass spectrometry (CapLC–ESI-MS–MS) for the detection and identification of casein deriving peptides in fined white wine is described. This is the first step towards the development of a liquid chromatography mass spectrometric method for the detection/identification of markers of potentially allergenic milk proteins used as wine fining agents. The method demonstrated to be capable of detecting some peptides arising from and casein (with the relative aminoacidic sequences elucidated) in extracts of white wine fined with casein at 100 and 1000g/mL. This MS based approach appears to be a useful tool for screening purposes as well as a confirmatory tool for the unequivocal identification of caseins in ELISA positive samples.

Peroxidation catalysed by Soybean Lypoxigenase was performed on tetralinoleyl-cardiolipin with the aim of generating selectively oxidized products, to be used subsequently as standards for studies on cardiolipin oxidation. The reaction products were characterized by LC-ESI-MS and MS/MS, and the process was found to link a hydroperoxylic group on one or more linoleic chains of cardiolipin, up to a total of four groups per molecule. Interestingly, the incidence of other oxidized products, like those arising from multiple hydroxylation or mixed hydroxylation-hydroperoxydation, previously observed after the chemical oxidation of the same cardiolipin, was found to be negligible. Moreover, evidences for the presence of the hydroperoxylic group(s) almost exclusively on carbon 13 of the linoleic chain(s) were obtained by MS/MS measurements. The enzymatic approach, integrated with a preparative separation step, which could be developed by adapting the chromatographic conditions adopted in the present work for analytical purposes, represents a promising strategy for the synthesis of highly specific monoor multi-peroxidated derivatives of cardiolipins.

A method of direct lipid analysis by matrix‐assisted laser desorption/ionization (MALDI) mass spectrometry (MS) in intact membranes, without prior extraction/separation steps, is described. Here, we demonstrate the efficacy of a strong base, 1,8‐bis(dimethylamino)naphthalene(DMAN; proton sponge), as a novel matrix for MALDI‐time‐of‐flight (TOF) MS analysis of whole cell bacteria. Initially, individual acidic low‐molecular‐weight analytes such as standard free fatty acids and phospholipids were analyzed using DMAN asmatrix. Clear negative‐modeMALDI‐TOFMS spectra of all analytes show only deprotonated analyte signals at a low picomole limit of detection with the complete absence of matrix‐related signals. These results indicate that DMAN represents a suitable matrix for MALDI‐TOF MS analysis of mixtures of complex lipids as the intact membranes of microorganisms. DMAN was successfully applied to the analysis of Lactobacillus sanfranciscensis and L. plantarum microorganisms. Different components were sensitively detected in a single spot, including 16:0, 18:2, 18:3, and 21:0 free acids, glycolipids, phosphatidylglycerols (PGs) and cardiolipins. This method might be of general application, offering the advantage of quickly gaining information about lipid components of other Gram‐positive bacterial membranes.

The major modifications induced by thermal treatment of whey proteins R-lactalbumin (R-La) and β-lactoglobulin (β-Lg) in a model system mimicking lactose-free milk (L- sugar mix) were investigated by matrix-assisted laser desorption ionization-time-of-flight mass spectrometry (MALDI-TOF MS). The analysis of the intact R-La revealed species with up to 7 and 14 adducts from lactose and sugar mix, respectively, whereas for β-Lg 3 and up to 5 sugar moieties were observed in the case of lactose and sugar mix experiments, respectively. A partial enzymatic hydrolysis with endoproteinase AspN prior to mass spectrometric analysis allowed the detection of further modifications and their localization in the amino acid sequence. Using R-cyano-4-chlorocinnamic acid as MALDI matrix, it could be shown that heating R-La and β-Lg with glucose or galactose led to the modification of lysine residues that are not glycated by lactose. The higher glycation degree of whey proteins in a lactose-free milk system relative to normal milk with lactose reflects the higher reactivity of monosaccharides compared to the parent disaccharide. Finally, the analysis of the whey extract of a commercial lactose-free milk sample revealed that the two whey proteins were present as three main forms (native, single, and double hexose adducts).

Escherichia coli (E. coli) is one of the most important foodborne pathogens to the food industry responsible for diseases as bloody diarrhea, hemorrhagic colitis and life-threatening hemolytic–uremic syndrome. For controlling and eliminating E. coli, metal nano- antimicrobials (NAMs) are frequently used as bioactive systems for applications in food treatments. Most NAMs provide controlled release of metal ions, eventually slowing down or completely inhibiting the growth of undesired microorganisms. Nonetheless, their antimicrobial action is not totally unraveled and is strongly dependent on metal properties and environmental conditions. In this work, we propose the use of matrix-assisted laser desorption ionization time-of-flight (MALDI TOF) mass spectrometry as a powerful tool for direct, time efficient, plausible identification of the cell membrane damage in bacterial strains exposed to copper-based antimicrobial agents, such as soluble salts (chosen as simplified AM material) and copper nanoparticles. E. coli ATCC 25922 strain was selected as ‘training bacterium’ to set up some critical experimental parameters (i.e. cell concentration, selection of the MALDI matrix, optimal solvent composition, sample preparation method) for the MS analyses. The resulting procedure was then used to attain both protein and lipid fingerprints from E. coli after exposure to different loadings of Cu salts and NPs. Inter- estingly, bacteria exposed to copper showed over-expression of copper binding proteins and degradation of lipids when treated with soluble salt. These findings were completed with other investigations, such as microbiological experiments.

The optimization of the electrochemical step in a combined (biological and electro-oxidative) landfill leachate treatment was performed using a two stages approach, response surface methodology coupled with the desirability function. Four constraints were imposed, namely the discharge limit for COD (i.e. 160 mg / L), the maximization of color removal, the minimization of both residual chlorine and specific energy consumption. Each variable was modeled employing a second-order regression model. Analysis of variance (ANOVA) showed coefficient of determination (R2) values greater than 0.96, ensuring satisfactory fitting of the model output with the experimental data. After optimization at current density of 133 mA/cm2, stirring speed of 566 rpm and reaction time 46.2 min, the constrained COD removal percentage of 78.2% (corresponding to the aforementioned discharge limit) and a color removal maximization of 99.3% were observed. In addition, the minimization of residual chlorine and specific energy consumption reached the values of 1213 mg/L and 42.4 kWh/m3, respectively. The proposed methodology proved to be effective for saving time and experimental effort guaranteeing the achievement of optimal combination factors to reach specific target response. It is also noticeably that the overall operating treatment cost was lower than that presently found for sanitary landfill leachates. However, the high residual chlorine production leading to final effluent AOX concentration up to 35 mgCl-/L, represents an intrinsic treatment drawback. Keywords: Landfill leachate, electrooxidation, response surface methodology, desirability optimization methodology, COD removal, colour removal

In this study, the simultaneous identification of lipids and proteins is achieved by matrix assisted laser desorption ionization - mass spectrometry (MALDI-MS) analysis after direct on-plate processing of micro-samples supported on graphite. Taking advantages of large surface area and thermal conductivity, graphite provided an ideal substrate for on-plate proteolysis and lipid extraction without interfering with MALDI analysis. The new protocol was first developed on simple standards as bovine serum albumin to set up the best experimental conditions for proteolysis. Then, its feasibility and performance were demonstrated by processing more complex samples as milk and egg powder for simultaneous lipid/protein analysis. By such a protocol, proteins could be efficiently digested on-plate within 15 minutes, with sequence coverages comparable to those obtained by conventional overnight in-solution digestion. As an additional feature, detection of hydrophilic phosphorylated peptides could be achieved without any further enrichment procedure. Furthermore, lipids could be identified in the same analysis without any additional treatment/processing step. The present strategy is simple and efficient, of large applicability, offering great promise for high-throughput proteo-lipidomics in very small samples since no conventional solvent extraction is required reducing sample loss.

The phospholipidome of blood microparticles (MPs) obtained from platelet-rich plasma of healthy individuals was characterized by hydrophilic interaction liquid chromatography (HILIC) coupled to electrospray ionization tandem mass spectrometry (ESI-MS/MS). The HILIC separation, performed on a silica stationary phase using an acetonitrile/methanol gradient, enabled the separation of several phospholipids (PL) classes, viz., phosphatidyl-cholines (PCs), -ethanolamines (PEs), -serines (PSs), -inositoles (PIs), sphyngomielins (SMs), and lyso forms of PCs and PEs. Structural characterization of species belonging to each class was performed by MS/MS measurements, in either positive or negative ion mode. The set of 131 phospholipids (including regioisomers) here identified represents the most comprehensive phospholipidomic characterization reported for human MPs. Although the phospholipidome composition of MPs and platelets, collected from the same donors, was found to be qualitatively the same, quantitative differences were evidenced for lyso-PCs, which appear to be significantly more abundant in MPs.

Ornithine lipids (OLs), a sub-group of the large (and of emerging interest) family of lipoamino acids of bacterial origin, contain a 3-hydroxy fatty acyl chain linked via an amide bond to the alpha -amino group of ornithine and via an ester bond to a second fatty acyl chain. OLs in extracts of Rhodobacter sphaeroides (R. sphaeroides) were investigated by high-performance reversed phase liquid chromatography (RPLC) with electrospray ionization mass spectrometry (ESI-MS) in negative ion mode using a linear ion trap (LIT). The presence of OLs bearing both saturated (i.e, 16:0, 17:0, 18:0, 19:0 and 20:0) and unsaturated chains (i.e., 18:1, 19:1, 19:2 and 20:1) was ascertained and their identification, even for isomeric, low abundance and partially co-eluting species, was achieved by low-energy collision induced dissociation (CID) multistage mass spectrometry (MSn, n = 2-4). OLs signatures found in two R. sphaeroides strains, i.e., wild type 2.4.1 and mutant R26, were examined and up to 16 and 17 different OL species were successfully identified, respectively. OLs in both bacterial strains were characterized by several combinations of fatty chains on ester-linked and amide-linked 3-OH fatty acids. Multistage MS spectra of monoenoic amide-linked 3-OH acyl chains, allowed the identification of positional isomer of OL containing 18:1 (i.e. 9-octadecenoic) and 20:1 (i.e. 11-eicosenoic) fatty acids. The most abundant OL ([M-H](-) at m/z 717.5) in R. sphaeroides R26 was identified as OL 3-OH 20:1/19:1 (i.e., 3-OH-eicosenoic acid amide-linked to ornithine and esterified to a nonadecenoic chain containing a cyclopropane ring). An unusual OL (m/z 689.5 for the [M-H](-) ion), most likely containing a cyclopropene ester-linked acyl chain (i.e., OL 3-OH 18:0/19:2), was retrieved only in the carotenoidless mutant strain R26. Based on the biosynthetic pathways already known for cyclopropa(e)ne ring-including acyl chains, a plausible explanation was invoked for the enzymatic generation of this ester-linked chain in R. sphaeroides. (C) 2015 Elsevier B.V. All rights reserved.

Reliable methods are needed for detection of allergenic milk proteins in complex food matrixes. The feasibility of an LC/high-resolution MS method for the analysis of milk proteins in a thermally processed model food (incurred cookies) and in white wine spiked, respectively, with milk powder and caseinate is described. Detection of milk proteins was based on the identification of unique peptides in the tryptic digests of cookie/wine extracts using an RP-HPLC separation coupled to an Exactive™ nonhybrid mass spectrometer using Orbitrap technology. The extremely high mass accuracy and resolution provided by the Orbitrap analyzer allowed a fast preliminary identification of four previously proposed peptide markers of caseins using only accurate values of the m/z of their ions. No interference was observed, despite the complexity of the analyzed matrixes. Moreover, the availability of a high- energy, collisionally activated dissociation cell integrated in the mass spectrometer enabled acquisition of peptide MS/MS-like spectra through post-source fragmentation. Confirmation of peptide marker identity could then be achieved by a comparison between experimental and predicted product ions. The described method shows the great potential of Orbitrap MS as a reliable technique in the field of protein allergen detection once the peptide markers are identified.

Oleuropein (Ole) has been claimed to mitigate cisplatin (CP) induced acute injury in kidney and liver of mice. In-vitro reactivity of hydrated CP species with Ole, and Ole metabolite hydroxytyrosol (HT) is of great interest as the preliminary step for gathering in-vivo information on the possible physiological role of the Ole/HT-cis-diammineplatinum (II) (Ole/HT-cis-DAP) conjugate.

Metal nanomaterials have emerging role in surface-assisted laser desorption ionisation–mass spectrometry (SALDI-MS) providing a useful tool to overcome some limitations intrinsically related to the use of conventional organic matrices in matrix-assisted LDI-MS. In this contribution, the possibility to use a stainless steel-supported gold nanoparticle (AuNP) film as a versatile platform for SALDI-MS was assessed. Sacrificial anode electrosynthetic route was chosen in order to obtain morphologically controlled core–shell AuNPs; the colloidal AuNPs were, thereafter, drop cast onto a stainless steel sample plate and the resulting AuNP film was thermally annealed in order to improve its effectiveness as LDI-MS promoter. Spectroscopic characterization of the nanostructured film by X-ray photoelectron spectroscopy was crucial for understanding how annealing induced changes in the surface chemistry and influenced the performance of AuNPs as desorption/ionisation promoter. In particular, it was demonstrated that the post-deposition treatments were essential to enhance the AuNP core/analyte interaction, thus resulting in SALDI-MS spectra of significantly improved quality. The AuNP films were applied to the detection of three different classes of low molecular weight (LMW) analytes, i.e. amino acids, peptides and LMW polymers, in order to demonstrate the versatility of this nanostructured material.

Low temperature treatments commonly applied to seafood products have been shown to influence their phospholipid (PL) profile through enzymatic hydrolysis. In the present study, the generation of lysophospholipids (LPL) resulting from this process was systematically investigated for selected, commercially relevant seafood products, namely oysters, clams, octopuses, and shrimps. These products were subjected to thermal treatments like refrigeration or freezing after being purchased as fresh, defrozen, or frozen products depending on the case. The coupling between hydrophilic interaction liquid chromatography (HILIC) and electrospray ionization with high resolution/accuracy Fourier transform mass spectrometry (ESI-FTMS) was exploited to evaluate the PL profile of the cited products, especially the incidence of LPL related to the two main PL classes of seafood products-phosphatidylcholines (PC) and phosphatidylethanolamines (PE)-in the lipid extracts. The lyso forms of PE (LPE) were found to be generally more sensitive than those of PC (LPC) to thermal treatments, usually exhibiting a significant increase upon prolonged refrigeration at 4 °C in all types of investigated products except European flat oysters. Moreover, the distinction between fresh and frozen or defrozen products could be achieved in the case of octopuses and shrimps, respectively.

La presente invenzione riguarda dispositivi sensori analiti gassosi comprendenti transistor a film sottile organico e, in particolare, sensori in grado di effettuare la discriminazione enantiomerica di analiti gassosi. I film sottili organici sono caratterizzati dal fatto di comprendere un composto di formula (I).

This invention pertains to gaseous analytes sensor devices comprising organic thin film transistor and, in particular sensors able to perform the enantiomeric discrimination of gaseous analytes. The organic thin films are characterized by comprising a compound of formula (I).