Special Issue with Research Topics on "Recent Analysis and Applications of Mass Spectra on Biochemistry".

Analytical mass spectrometry applies irreplaceable mass spectrometric (MS) methods to analytical chemistry and chemical analysis, among other areas of analytical science [...].

Mass Spectrometric Identification of Metabolites after Magnetic-Pulse Treatment of Infected Pyrus communis L. Microplants.

The major goal of this study is to create a venue for further work on the effect of pulsed magnetic fields on plant metabolism. It deals with metabolite synthesis in the aforementioned conditions in microplants of Pyrus communis L. So far, there have been glimpses into the governing factors of plant biochemistry in vivo, and low-frequency pulsed magnestatic fields have been shown to induce additional electric currents in plant tissues, thus perturbing the value of cell membrane potential and causing the biosynthesis of new metabolites. In this study, sixty-seven metabolites synthesized in microplants within 3-72 h after treatment were identified and annotated. In total, thirty-one metabolites were produced. Magnetic-pulse treatment caused an 8.75-fold increase in the concentration of chlorogenic acid (RT = 8.33 ± 0.0197 min) in tissues and the perturbation of phenolic composition. Aucubin, which has antiviral and antistress biological activity, was identified as well. This study sheds light on the effect of magnetic fields on the biochemistry of low-molecular-weight metabolites of pear plants in vitro, thus providing in-depth metabolite analysis under optimized synthetic conditions. This study utilized high-resolution gas chromatography-mass spectrometry, metabolomics methods, stochastic dynamics mass spectrometry, quantum chemistry, and chemometrics, respectively. Stochastic dynamics uses the relationships between measurands and molecular structures of silylated carbohydrates, showing virtually identical mass spectra and comparable chemometrics parameters.

Stochastic Dynamic Mass Spectrometric Quantitative and Structural Analyses of Pharmaceutics and Biocides in Biota and Sewage Sludge.

Mass spectrometric innovations in analytical instrumentation tend to be accompanied by the development of a data-processing methodology, expecting to gain molecular-level insights into real-life objects. Qualitative and semi-quantitative methods have been replaced routinely by precise, accurate, selective, and sensitive quantitative ones. Currently, mass spectrometric 3D molecular structural methods are attractive. As an attempt to establish a reliable link between quantitative and 3D structural analyses, there has been developed an innovative formula [DSD″,tot=∑inDSD″,i=∑in2.6388.10-17×Ii2¯-Ii¯2] capable of the exact determination of the analyte amount and its 3D structure. It processed, herein, ultra-high resolution mass spectrometric variables of paracetamol, atenolol, propranolol, and benzalkonium chlorides in biota, using mussel tissue and sewage sludge. Quantum chemistry and chemometrics were also used. Results: Data on mixtures of antibiotics and surfactants in biota and the linear dynamic range of concentrations 2-80 ng.(mL)-1 and collision energy CE = 5-60 V are provided. Quantitative analysis of surfactants in biota via calibration equation ln[D″SD] = f(conc.) yields the exact parameter |r| = 0.99991, examining the peaks of BAC-C12 at m/z 212.209 ± 0.1 and 211.75 ± 0.15 for tautomers of fragmentation ions. Exact parameter |r| = 1 has been obtained, correlating the theory and experiments in determining the 3D molecular structures of ions of paracetamol at m/z 152, 158, 174, 301, and 325 in biota.

Stochastic dynamic ultraviolet photofragmentation and high collision energy dissociation mass spectrometric kinetics of triadimenol and sucralose.

The major goal of the paper is to provide empirical proof of view that innovative stochastic dynamic mass spectrometric equation D″SD = 2.6388·10-17·(< I2 > - < I > 2) determines the exact analyte concentration in solution via quantifying experimental variable intensity (I) of an analyte ion per any short span of scan time of any measurement, which also appears applicable to quantify laser-induced ultraviolet photofragmentation and high energy collision dissociation mass spectrometric processes. Triadimenol (1) and sucralose (2) using positive and negative polarity are examined. Laser irradiation energy λex = 213 nm is utilized. The issue is of central importance for monitoring organic micro-pollutants in surface, ground, and drinking water as well as tasks of risk assessment for environment and human health from contamination with organics. Despite the significant importance of the topic, answering the question of functional kinetic relations of such processes is by no means straightforward, so far, due to a lack of in-depth knowledge of mechanistic aspects of fragment paths of analytes in environment and foods as well as kinetics of processes under ultraviolet laser irradiation. Although there is truth in the classical theory of first-order reaction kinetics, it does not describe all kinetic data on analytes (1) and (2). A new damped sine wave functional response to a large amount of kinetics is presented. High-resolution mass spectrometric data and chemometrics are used. The study provides empirical evidence for claim that temporal behavior of mass spectrometric variable intensity under negative polarity obeys a certain scientific law written by means of equation above. It is the same for positive and negative soft-ionization mass spectrometric conditions.

Mass spectrometric stochastic dynamic 3D structural analysis of mixture of steroids in solution - Experimental and theoretical study.

There is explored, herein, functional relation: Experimental mass spectrometric phenomenon, obeying a certain scientific law â‡” 3D molecular conformations and electronic structures of analytes obtained for quantum chemical theories. The paper answers to questions: (a) What evidence claims these actual relations among measurable and theoretical parameters, experimental factors and molecular properties; (b) how the provided evidence is collected and used; and (c) how empirical proof relates to assign and explain mass spectrometric phenomena of steroids afforded by our innovative stochastic dynamic mass spectrometric formula, D″SD = 2.6388.10-17.(-2), quantum chemical 3D conformations, electronic structures and energetics of molecules, respectively. The paper address issue concerning empirical evidence at very high-to-exact level of assignment of 3D molecular conformations of steroids to experimental mass spectrometric fragment ions, accounting precisely for (i) effect of protonation; (ii) intramolecular rearrangement for A-D rings of steroidal skeleton and proton transfer effect, if any; in addition to (iii) examination of enantiomers of steroids in mixture with different stereochemistry, (R) and (S), of a set of six atoms of the molecular backbone of hydrocortisone (1), deoxycorticosterone (2), progesterone (3) and methyltestosterone (4), respectively. Results from testosterone (5) are discussed, as well. There are used ultra-high resolution atmospheric pressure chemical ionization mass spectrometric data on analytes (1)-(4) at ng.(mL)-1 concentration levels in mixtures in solution obtained for positive operation mode. High accuracy static and molecular dynamic quantum chemical computations and chemometrics are also utilized. Experimental 3D structural parameters of steroids obtained for stochastic dynamic diffusion theory are correlated with available crystallographic data.

Stochastic dynamic mass spectrometric quantification of steroids in mixture - Part II.

This paper deals with quantification of the following steroids in mixture: hydrocortisone (1), deoxycorticosterone (2), progesterone (3) and methyltestosterone (4) by means of mass spectrometry and implementing our innovative stochatic dynamic functional relationship between the analyte concentration in solution and the experimental variable intensity. The mass spectrometric data are correlated independently using chromatography. Chemometric analysis is carried out.

A mass spectrometric stochastic dynamic diffusion approach to selective quantitative and 3D structural analyses of native cyclodextrins by electrospray ionization and atmospheric pressure chemical ionization methods.

The paper addressed shortcoming with highly precise and selective 3D structural analysis of native cyclodextrins in mixture using ions observable at low m/z-region by ESI- and APCI-mass spectrometry. Because of, the quantitative and structural analyses of CDs, in general, are vexed by a set of complications. The study outlines our own stochastic dynamic approaches to the latter issues based on new model relations, quantifing the measurable MS outcome intensity. They introduce the so-called stochastic dynamic mass spectrometric diffusion "DSD" parameter, exhibiting high accuracy, precision, sensitivity and selectivity, respectively. It is linearly connected with the so-called quantum chemical diffusion parameter "DQC" according to Arrhenius's theory. The most important upshot is that statistical parameters r = 0.99639-0.99981 has been obtained correlating between DSD and DQC parameters. Therefore, we determine high accurately 3D molecular and electronic structures of analytes by mass spectrometry. Fragment peaks at m/z 313, 279, 272, 252, 231, 214, 198, 171, 158 and 141 are examined. Mixtures of CDs and monomeric and acyclic oligomer carbohydrates glucose (1), sucrose (2), raffinose (3), melezitose (4) and cellotriose (5) are also studied. Our method is able to account precisely for the effect of the temperature under ESI- and APCI-MS conditions, as well. Correlative analysess between DSD parameters of ESI- and APCI-MS measurements under different temperatures is also shown. Chemometric tests are used. Another important results and conclusions, among others, to draw from this research are: (i) excellent linear correlation between DSD and DQC parameters of r = 0.99636 is found looking at common ions at m/z 141, 158 and 171, belonging to 2-formyl-3,4-dihydroxy-pyranylium, 4,5,6-trihydroxy-6H-pyran-2-carbaldehyde and 3,4,5-trihydroxy-6-oxo-6H-pyran-2-ylmethylidyne-oxonium ions. Thus, we distinguish precisely between the last structure and 3-formyl-4,5-dihydroxy-2,7-dioxa-8-oxonia-bicyclo[4.2.0]octa-1(8),3,5-triene cation. In the case of ion at m/z 141 subtle electronic effects are distinguished between the mentioned structure and the charged 3,4-dihydroxy-6H-pyran-2-carbaldehyde one. The method determines precisely very similar structurally poly-OH-substituted derivatives. Because of, (ii) absolute reproducibility (r = 1) of DSD parameters of ESI-MS spectra is obtained studying the shown in point (i) MS peaks of ß-CD between jth and jth numbers of experiments. The statistical equation is DiSD = (0.51 ±â€¯3.1.10-5) × DjSD; (iii) the APCI- and ESI-MS provide identical results studying common MS ions of CDs and the correlation between DAPCISD and DESISD parameters excludes from error, due to, experiment; and (iv) The correlation between theory and experiment accounting for the factor temperature within our model equations shows r = 0.9828 looking at the MS peaks at m/z 313 280, 279, 274 and 252, respectively. The effect of the temperature under both ESI- and APCI-MS conditions on the 3D molecular and electronic structures of CDs is precisely studied, respectively.

Collision-induced thermochemistry of reactions of dissociation of glycyl-homopeptides-An experimental and theoretical analysis.

The research draws on experimental and theoretical data about energetics and kinetics of mass spectrometric (MS) reactions of glycyl homopenta- (G5) and glycyl homohexapeptides (G6). It shows the great applicability of the methods of quantum chemistry to predict MS profile of peptides using energetics of collision induced dissociation (CID) fragment species. Mass spectrometry is among irreplaceable methods, providing unambiguous qualitative, quantitative and structural information about analytes, applicable to many scientific areas like environmental chemistry; food chemistry; medicinal chemistry; and more. Our study could be considered of substantial interdisciplinary significance, where MS proteomics is widely used. The experimental design involves electrospray ionization (ESI) and CID MS/MS. Theoretical design is based on ab initio and density functional theory (DFT) methods. Experimental MS and theoretical free Gibbs energies as well as rate constants of fragment reactions are compared. The thermodynamic encompasses gas-phase and polar continuum analysis, including polar protic and aprotic solvents within temperature T = 10-500 K; dielectric constant ε = 0-78, pH, and ionic strengths µ = 0.001-1.0 mol dm-1 . There are computed and discussed 39 protonated forms of peptides at amide N- and -(NHC)=O centers; corresponding fragment ions studying their thermodynamic stability depending on experimental conditions. A correlation analysis between molecular conformations of parent ions and fragment species; their proton accepting ability and internal energy distribution is carried out. Data about ionization potentials (IPs) and electron affinities (EAs) are discussed, as well.

Molecular and environmental factors governing non-covalent bonding interactions and conformations of phosphorous functionalized γ-cyclodextrin hydrate systems.

Recent strategies in molecular drugs-design shift efforts to nanomedicine. Large supra-molecular inclusion systems are implemented as therapeutics. The sophistication of design is based on major advances of cyclodextrins (CDs) as host molecules. They are friendly towards biological environment. CDs have good (bio)compatibility as well. CDs can form host-guest macromolecular systems incorporating small molecules with suitable shapes due to non-covalent interactions. Innovative strategies yield to polymeric nano-particles; micelles; linear polymers and/or CDs-functionalized dendrimeric nanostructures; nanofibers as well as hydrogels. Attractive are phosphorous containing (bio)matrerials, having high selectivity toward biological active molecules. The non-covalent interactions in aquatic CD-systems contribute to stability of host-guest systems under physiological conditions, determining conformational preferences of host-CD macromolecule and guest small molecular template. In this paper we have reported complementation application of mass spectrometric (MS) and quantum chemical analysis of phosphorous chemically substituted γ-cyclodextrin hydrates γ-CDPO/nH2O (n ∊ [0-14]), studying neutral and polynegatively charged molecules as an effort to describe realistic a representative scale of physiological conditions. The binding affinity and molecular conformations are discussed. The 250 neutral and charged systems (γ-CDPOHm/nH2O, n ∊ [10][0,14], m ∊ [0,15], γ-CDPOH-8/nH2O.8Na(+), and γ-CDPOH-16/nH2O.16Na(+)) in four main domains of non-covalent hydrogen bonding interactions are studied.

Environmental modeling of uranium interstitial compositions of non-stoichiometric oxides: experimental and theoretical analysis.

Study of uranium interstitial compositions of non-stoichiometric oxides UO2+x (x ∈ 0.1-0.02) in gas and condense phases has been presented, using various soft-ionization mass spectrometric methods such as ESI-, APCI-, and MALDI-MS at a wide dynamic temperature gradient (∈ 25-300 °C). Linearly polarized vibrational spectroscopy has been utilized in order to assign unambiguously, the vibrational frequencies of uranium non-stoichiometric oxides. Experimental design has involved xUO2.66·yUO2.33, xUO2.66·yUO2.33/SiO2, xUO2.66·yUO2.33/SiO2 (NaOH) and SiO2/x'NaOH·y'UO2(NO3)2·6H2O, multicomponent systems (x = 1, y ∈ 0.1-1.0 and x' = 1, y' ∈ 0.1-0.6) as well as phase transitions UO2(NO3)2·6H2O â†’ {U4O9(UO2.25)} â†’ U3O7(UO2.33) â†’ U3O8(UO2.66) â†’ {UO3}, thus ensuring a maximal representativeness to real environmental conditions, where diverse chemical, geochemical and biochemical reactions, including complexation and sorption onto minerals have occurred. Experimental factors such as UV-irradiation, pH, temperature, concentration levels, solvent types and ion strength have been taken into consideration, too. As far as uranium speciation represents a challenging analytical task in terms of chemical identification diverse coordination species, mechanistic aspects relating incorporation of oxygen into UO 2+x form the shown full methods validation significantly impacts the field of environmental radioanalytical chemistry. UO2 is the most commonly used fuel in nuclear reactors around the globe; however, a large non-stoichiometric range ∈ UO1.65-UO2.25 has occurred due to radiolysis of water on UO2 surface yielding to H2O2, OH(·), and more. Each of those compositions has different oxygen diffusion. And in this respect enormous effort has been concentrated to study the potential impact of hazardous radionuclide on the environment, encompassing from the reprocessing to the disposal stages of the fuel waste, including the waste itself, the processes in the waste containers, the clay around the containers, and geological processes. In a broader sense, thereby, this study contributes to field of environmental analysis highlighting the great ability of various soft-ionization MS methods, particularly, MALDI-MS one, for direct assay of complex multicomponent heterogeneous mixtures at fmol-attomol concentration ranges, along with it the great instrumental features allowing, not only meaningful quantitative, but also structural information of the analytes, thus making the method indispensable for environmental speciation of radionuclides, generally.

Solid-state UV-MALDI mass spectrometric quantitation of fluroxypyr and triclopyr in soil.

The work presented here refers firstly to solid-state UV-MALDI-Orbitrap-mass spectrometric analysis of fluroxypyr (A) and triclopyr (B) in soils under laboratory conditions. The experimental design has involved the following: (a) determination of analytes A and B in polycrystalline composites of organic materials 1-7, based on 2-piperidine (pyrrolidine or piperazine)-1-yl-ethyl ammonium salts in order to determine the effect of sample preparation techniques on method performance using commercial herbicide formulations and (b) analysis of non-(X j,k,l (i) ) and sterilized (Y j,k,l (i) ) soil samples (i-fold rate 1, 10, 100, or 1,000; j-pesticide type A or B; k-time (0, 5, 10, 20, and 50 days) and l = 1-3 replicated samples) having clay content ∈ 5.0-12.0 %, silt ∈ 23.0-51.1 %, sand ∈ 7.2-72.0 %, and pH ∈ 4.0-8.1. In order to obtain a high representativeness of the data toward real-field experiments, the pollution scheme has involved 1-, 10-, 100-, and 1,000-fold rates. The firstfold rate has concentration of pollutant A of 2.639 × 10(-4) g in 625 cm(2) soil horizon of 0-25 cm(2) (5 cm depth) according to registration report (PSM-Zulassungbericht) of German Federal Office of Consumer Protection and Food Safety (Bundesamt für Verbraucherschutz und Lebensmittelsicherheit) 6337/26.10.2009. The experimental design has involved quincunx systematic statistical approach for collection of soil samples. The performance has been compared with the corresponding statistical variable obtained, using an independent HPLC-ESI-(APCI-)-MS/MS analysis.

Quinoxalines as potent selective CRFRs ligands for monitoring and brain diagnostic.

The paper highlighted quinoxalines as potent ligands to corticotropin-releasing factor receptor types 1 and 2. The content includes design and structure-activity relationship of 50 model substances to CRFR1, CRFR2α and CRF2ß, respectively. It is important to bear in mind, that our concept has based on challenging research task, designing for selective CRFRs ligands. Because,: (i) These macromolecules can bond more than one ligand, thus causing for a distinct physiological response; (ii) CRFRs also participate readily in protein-protein interactions; (iii) CRFRs have two step activation mechanism and; (iv) CRFR1 has low selectivity. In spite of, numerous research efforts, which have been devoted to the isolation of series peptidic and non-peptidic CRFRs agonists, the poor penetration across blood-brain barrier restricts, their wide application in the clinical practice. Furthermore, the biological role of CRFR2 is not yet fully understood. For that reason, the studies of the structure-activity relationship have significant impact in the field. The great advantages of quinoxalines as prospective ligands are based on their: (a) One-step synthetic road, using mild experimental conditions and, allowing to involve various functional groups in the molecular scaffold as well as good-to-excellent yields, employing Fischer and Hinsberg methods; (b) High selectivity to CRFRs sub-types and; (c) Tunable fluorescence emission within the frame of a large scale of the electromagnetic spectrum ∈ 500-700 nm.

Adsorption of uranium composites onto saltrock oxides - experimental and theoretical study.

The study encompassed experimental mass spectrometric and theoretical quantum chemical studies on adsorption of uranium species in different oxidation states of the metal ion, and oxides of UxOy(n+) type, where x = 1 or 3, y = 2 or 8, and n = 0, 1 or 2 onto nanosize-particles of saltrock oxides MO (M = Mg(II), Ca(II), Ni(II), Co(II), Sr(II) or Ba(II)), M2Oy (M = Au(III) or Ag(I), y = 3 or 1) silicates 3Al2O3.2SiO2, natural kaolinite (Al2O2·2SiO2·2H2O), illite (K0.78Ca0.02Na0.02(Mg0.34Al1.69Fe(III)0.02)[Si3.35Al0.65]O10(OH)2·nH2O), CaSiO3, 3MgO·4SiO2,H2O, and M(1)M(2)(SiO4)X2 (M(1) = M(2) = Al or M(1) = K, M(2) = Al, X = F or Cl), respectively. The UV-MALDI-Orbitrap mass spectrometry was utilized in solid-state and semi-liquid colloidal state, involving the laser ablation at λex = 337.2 nm. The theoretical modeling and experimental design was based on chemical-, physico-chemical, physical and biological processes involving uranium species under environmental conditions. Therefore, the results reported are crucial for quality control and monitoring programs for assessment of radionuclide migration. They impact significantly the methodology for evaluation of human health risk from radioactive contamination. The study has importance for understanding the coordination and red-ox chemistry of uranium compounds as well. Due to the double nature of uranium between rare element and superconductivity like materials as well as variety of oxidation states ∈ (+1)-(+6), the there remain challenging areas for theoretical and experimental research, which are of significant importance for management of nuclear fuel cycles and waste storage.

Evodiamine and rutaecarpine alkaloids as highly selective transient receptor potential vanilloid 1 agonists.

Despite that among non-camptothecin natural products promising anticancer therapeutics are evodiamine derivatives, involved into mechanism of physiological function of topoisomerase-I. But, more recent findings have been shown that substituted quinazole alkaloids act as transient receptor potential vanilloid 1 agonists. The TRP(V1) is a calcium ion channel, activated by pH, heat and inflammatory activators. I is implicated in pain sensing. TRPV1 agonist is capsaicine (1). Both 1 and evodiamine (2), therefore, produce same physiological response, but are structurally unrelated from chemical viewpoint. Furthermore precise mechanistic aspects of drugs receptor interactions are still not fully understood. This study is the first one, which provides assessment of molecular factors contributing significantly to selectivity of 2 and rutaecarpine (3) as well as their twenty-two new functionalized derivatives towards (TRP)V1. The suggested new functionalization type of molecular skeleton, which is completely different one in respect the known derivatives, which is implicated in treatment of variety of cancer cell lines interacting preferably with topoisomerase-I. It resulted to increasing of the binding affinity and selectivity of the functionalized derivatives specifically to (TRP)V1∈1.36-1.72 and ∈2.50-3.16 higher than 1-3.

Uranyl-water-containing complexes: solid-state UV-MALDI mass spectrometric and IR spectroscopic approach for selective quantitation.

Since primary environmental concept for long storage of nuclear waste involved assessment of water in uranium complexes depending on migration processes, the paper emphasized solid-state matrix-assisted laser desorption/ionization (MALDI) mass spectrometric (MS) and IR spectroscopic determination of UO2(NO3)2·6H2O; UO2(NO3)2·3H2O, α-, ß-, and γ-UO3 modifications; UO3·xH2O (x = 1 or 2); UO3·H2O, described chemically as UO2(OH)2, ß- and γ-UO2(OH)2 modifications; and UO4·2H2O, respectively. Advantages and limitation of vibrational spectroscopic approach are discussed, comparing optical spectroscopic data and crystallographic ones. Structural similarities occurred in α-γ modifications of UO3, and UO2(OH)2 compositions are analyzed. Selective speciation achieved by solid-state mass spectrometry is discussed both in terms of its analytical contribution for environmental quality assurance and assessment of radionuclides, and fundamental methodological interest related the mechanistic complex water exchange of UO3·H2O forms in the gas phase. In addition to high selectivity and precision, UV-MALDI-MS, employing an Orbitrap analyzer, was a method that provided fast steps that limited sample pretreatment techniques for direct analysis including imaging. Therefore, random and systematic errors altering metrology and originating from the sample pretreatment stages in the widely implemented analytical protocols for environmental sampling determination of actinides are significantly reduced involving the UV-MALDI-Orbitrap-MS method. The method of quantum chemistry is utilized as well to predict reliably the thermodynamics and nature of U-O bonds in uranium species in gas and condensed phases.

UV-MALDI mass spectrometric quantitation of uracil based pesticides in fruit soft drinks along with matrix effects evaluation.

This study focused on the development of the accurate and precise quantitative method for the determination of pesticides bromacil (1), terbacil (2), lenacil (3), butafenacil (4) and flupropacil (5) in fruit based soft drinks. Three different types of drinks are bought from market; huddled orange fruit drink (100%) (I), red-oranges (II) and multivitamin drink containing strawberry, orange, banana and maracuja (III). Samples were analyzed "with" and "without" pulp utilizing LC-ESI (or APCI) MS/MS, HPLC-ESI-(or APCI)-MS/MS and UV-MALDI-Orbitrap-MS methods. The effect of high complexity of the food matrix on the analysis was discussed. Study focuses on the advantages of the UV-MALDI-Orbitrap-MS method compared to the traditionally involved GC alone or hybrid methods such as GC-MS and LC-MS/MS for quantification of pesticides in water and soft drinks. The developed method included the techniques performed for validation, calibration and standardization. The target pesticides are widely used for the treatment of citrus fruits and pineapples, but for soft drink products, there are still no clear regulations on pesticide residues limits. The matrix effects in the analysis of fruit drinks required implementation of the exact standard reference material corresponds to the variety of food matrices. This paper contributed to the broad analytical implementation of the UV-MALDI-Orbitrap-MS method in the quality control and assessment programs for monitoring of pesticide contamination in fruit based sodas.

Solid-state UV-MALDI-MS assay of transition metal dithiocarbamate fungicides.

The determination of transition metal containing dithiocarbamate fungicides represents a challenging aspect of analytical object. They have a low stability, low solubility and stabilize versatile coordination monomers, dimers, disulfides and/or S-oxidized derivatives. Their diverse biological activities and agricultural implementation encompass plant prevention and crop protection against a variety of plants containing fungi and diseases of 400 pathogens and 70 cultures. Nonetheless, those dithiocarbamates (DTCs) are banned for agricultural use in Europe or have expiration at years 2016-2017 because of their highly toxic degradation products and/or metabolites, in particular ethylene thiourea; they found large-scale implementations in materials research and medicine. Despite the broad interdisciplinary of DTC application, due to the above reasons, they have received little attention in the rapidly growing field of analytical chemistry, and in particular, the analytical mass spectrometry. Therefore, the study reported on qualitative, quantitative and structural analysis of ten DTCs (1-10), using the matrix assisted laser desorption/ionization (UV-MALDI)-Orbitrap-mass spectrometry (MS) contributed considerably to the implementation of the method for environmental and foodstuffs monitoring. Its ultrahigh resolving power and capacity for direct solid-state analysis, at limited number of sample pretreatment steps, at concentration levels of analytes of up to femtogram per gram resulted to achievement of a highly precise analytical information for these non-trivial objects. The presented fully validated method and technique is based on the successful ionization of DTCs embedded in three novel organic salts (M1-M3). In this regard, the reported MS and the single-crystal X-ray diffraction data as well as the quantum chemical one are able to correlate the molecular structures in condense and in the gas phase. Despite the novelty of the fundamental methodological character of the research reported, the promising metrology contributed to the applied aspect of the UV-MALDI-MS as a robust analytical method for environmental and foodstuffs monitoring, which is tested on two commercially available crop protecting products such as Mancozeb® and Antracol®, respectively.

Macromolecular ensembles of cyclodextrin crystallohydrates and clathrates--experimental and theoretical gas--and condense phase study.

The paper reported a joined mass spectrometric, crystallographic and quantum chemical study of crystallohydrates, emphasizing on clathrates of native α-, and ß-cyclodextrins as well as their randomly acetylated derivatives (4 and 5). The physical data are compared with 19 crystals of CDs, three of which new ones, differed by number of crystallohydrate (and/or clathrate) molecules (n)). The macroscopic complex CDs/n stability (n∈ [0.60-12.26]) is evaluated theoretically, accounting the surface and clathrate self-assembly of non-covalent hydrogen bonding interactions. The variety of competitive condensation processes of randomly acetylated products and the non-specific phase transition adduct of CDs and aggregates, which complicated significantly the MS picture are discussed. The single crystal X-ray diffraction, enable to determine the non-covalent interactions in CDs crystals, which physical phenomena in the gas-phase and crystalline phase → liquid phase → GP and CP → GP transitions are evidenced mass spectrometrically. The quantum chemical method provided important thermodynamics and structural information at variety of states, allowing understanding comprehensively the complex GP phenomena. Special emphasis in the paper content is dedicated to the phenomenology of the GP mass spectrometric ionization processes and thermodynamics of fragmentation molecular ions of CDs and their supramolecular self-assembly which, strongly depends on the experimental factors.