MALDI-TOF MS characterization of polystyrene synthesized by ATRP

In this work, we investigated the peculiar peaks found in the MALDI-TOF mass spectra of polystyrenes (PS) with a bromine end prepared by atom transfer radical polymerization when silver trifluoroacetate (AgTFA) and THF were used as cationization agent and solvent, respectively, in the MALDI sample preparation. In the MALDI mass spectrum, PS with a terminal bromine was not detected but the species with a terminal double bond (U series), and −22 m/z (T series) and +18 m/z (W series) peaks relative to U series appeared as major peaks. While the U species was reported as a result of the elimination reaction of HBr, but the origin and the structure of the other species have not been elucidated. We found that the −22 m/z peak of U_n is in fact T_n-2, which is the adduct of THF and the anion of the Ag salt, TFA⁻ (+186 m/z) to U_n-2. The +18 m/z peak was confirmed to be the species with a terminal OH. All these reactions were catalyzed by Ag salt and the T and W series were not found at all when NaTFA was used as a cationization agent.     

Surface quantitative characterization of poly(styrene-co-4-vinyl phenol)/poly(styrene-co-4-vinyl pyridine) blends with controlled hydrogen bonding interactions

Time-of-flight secondary ion mass spectrometry (ToF-SIMS) was used to quantitatively correlate to the surface chemical composition determined from XPS in poly(styrene-co-4-vinyl phenol) (STVPh)/poly(styrene-co-4-vinyl pyridine) (STVPy) blends or complexes when the hydroxyl contents in STVPh copolymers were gradually increased. It was found that different mixing thermodynamics such as immiscibility, miscibility and complexation has little effect on the quantitative analysis of surface concentrations in the blends or complexes using ToF-SIMS. In the positive spectra, the normalized intensities or relative peak intensities can both be used to quantitatively analyze the surface vinyl phenol (VPh), styrene and vinyl pyridine (VPy) concentrations when peaks at m/z=119, 120 are used for VPh, peaks at m/z=103, 105, 115 for styrene and peaks at m/z=80, 93, 106 for VPy monomer units. In the negative spectra, the normalized intensities of peaks characteristic of VPh monomer units (m/z=16, 17, 93) seems to be not affected by hydrogen bonding formation and can be used in quantitative analysis.     

Composition of negative air ions as a function of ion age and selected trace gases: Mass- and mobility distribution

In order to explore an additional window to look into the mechanisms behind atmospheric ion and particle formation, an advanced method, which combines the study of ageing of air ions by both mobility and mass spectrometry is developed and examined. The technique behind this method can produce new air ions and trace their evolution within the age interval from a few tenths of a second up to about 20 s. We measure the mobility spectra from 2.37 down to 0.0013 cm² V^?1 s^?1 and the mass spectra of these ions up to m/z 2000. The results demonstrate the ability of the method to trace the temporal evolution of the ions. The composition of negative air ions at an age of about 1 s is clearly different from that at about 20 s, contrarily to certain former results according to which the small ion evolution should mainly terminate within about a second. We investigate how variations in humidity and the elevated concentrations of iodine and diethylamine (DEA) modify the composition of the negative air ions. The concentrations of DEA and iodine are above their common values in the air, but also in these cases the observed trends should be applicable to the atmosphere. All the vapours investigated in this study modify the ion composition in quite a specific way. Most prominent transformations are induced by iodine, which transforms the mass spectrum of cluster ions into few dominant peaks at m/z 381 and 635. In mobility spectrum, it generates a large number of new heavy ions with the sizes of 4?40 nm, the heavy ions in turn decrease the concentration of cluster ions due to ion–aerosol attachment. The peaks at m/z 381 and 635 can be assigned to ions I^?(I₂) and I^?(I₂)₂, respectively. At an enhanced concentration of diethylamine vapour (DEA), the new ions NO₃^?(HNO₃)(DEA) seem very plausible to explain the appearance of the peak at m/z 198 in the mass-spectrum. DEA evokes a multimodal mobility spectrum with modes at about 1.75, 10 and 20 nm. Both the DEA and iodine generate the changes in the size distribution of aerosol particles, which can be associated with a new particle formation. The experiments with enhanced water vapour concentrations revealed a new peak at m/z 250, which could be assigned to HCO₃^?(HNO₃)₃ ions.     

Ultra-High Performance Liquid Chromatography-High Resolution Mass Spectrometry and High-Sensitivity Gas Chromatography-Mass Spectrometry Screening of Classic Drugs and New Psychoactive Substances and Metabolites in Urine of Consumers

The use of the new psychoactive substances is continuously growing and the implementation of accurate and sensible analysis in biological matrices of users is relevant and fundamental for clinical and forensic purposes. Two different analytical technologies, high-sensitivity gas chromatography-mass spectrometry (GC-MS) and ultra-high-performance liquid chromatography-high-resolution mass spectrometry (UHPLC-HRMS) were used for a screening analysis of classic drugs and new psychoactive substances and their metabolites in urine of formed heroin addicts under methadone maintenance therapy. Sample preparation involved a liquid-liquid extraction. The UHPLC-HRMS method included Accucore™ phenyl Hexyl (100 × 2.1 mm, 2.6 μm, Thermo, USA) column with a gradient mobile phase consisting of mobile phase A (ammonium formate 2 mM in water, 0.1% formic acid) and mobile phase B (ammonium formate 2 mM in methanol/acetonitrile 50:50 (v/v), 0.1% formic acid) and a full-scan data-dependent MS2 (ddMS2) mode for substances identification (mass range 100–1000 m/z). The GC-MS method employed an ultra-Inert Intuvo GC column (HP-5MS UI, 30 m, 250 µm i.d, film thickness 0.25 µm; Agilent Technologies, Santa Clara, CA, USA) and electron-impact (EI) mass spectra were recorded in total ion monitoring mode (scan range 40–550 m/z). Urine samples from 296 patients with a history of opioid use disorder were examined. Around 80 different psychoactive substances and/or metabolites were identified, being methadone and metabolites the most prevalent ones. The possibility to screen for a huge number of psychotropic substances can be useful in suspected drug related fatalities or acute intoxication/exposure occurring in emergency departments and drug addiction services.     

Protein Profiling of Blood Samples from Patients with Hereditary Leiomyomatosis and Renal Cell Cancer by Surface-Enhanced Laser Desorption/Ionization Time-of-Flight Mass Spectrometry

Hereditary leiomyomatosis and renal cell cancer (HLRCC) is an extremely rare syndrome with autosomal dominant inheritance. HLRCC is characterized by a predisposition to leiomyomas of the skin and the uterus as well as renal cell carcinoma. The disease-related gene has been identified as fumarate hydratase (fumarase, FH), which encodes an enzyme involved in the mitochondrial tricarboxylic acid cycle. Protein profiling may give some insight into the molecular pathways of HLRCC. Therefore, we performed protein profiling of blood samples from HLRCC patients, their family members, and healthy volunteers, using surface-enhanced laser desorption/ionization time-of-flight mass spectrometry (SELDI-TOF MS) coupled with IMAC-Cu chips. For hierarchical clustering analysis, we used the 45 peaks that revealed significant differences in single-marker analysis over the range from 1500 to 15,000 m/z. Heat map analysis based on the results of clustering distinguished the HLRCC kindred from non-HLRCC subjects with a sensitivity of 94% and a specificity of 90%. SELDI-TOF MS profiling of blood samples can be applied to identify patients with HLRCC and to assess specific molecular mechanisms involved in this condition.     

Characterization of Organic Particles from Incense Burning Using an Aerodyne High-Resolution Time-of-Flight Aerosol Mass Spectrometer

Incense burning is a common ritual in Asian communities both indoors in residential homes and outdoors in temple premises. Organic particles from burning of incense sticks, incense coils, and mosquito coils after extensive dilution (>1000×) were characterized by the Aerodyne high-resolution time-of-flight aerosol mass spectrometer (HR-ToF-AMS). The obtained mass spectra in general resemble those reported for biomass burning aerosols. Ion peaks with m/z values higher than 100 accounted for 15%–25% of the organic signals in the unit-mass-resolution (UMR) mass spectra. In the high-resolution (HR) mass spectra, the ion peaks at m/z 60 and 73 are found to be related to the sugar anhydrides as in particles from other biomass burning processes. In addition, the ion peaks at m/z 107, 121, 137, 151, 167, and 181, some of which (e.g., m/z 137 and 167) have been observed in particles from biomass burning but not yet assigned, were assigned to lignin-related components. Elemental analysis from the HR data reveals that a large portion of particulate organics from incense burning are oxygenated (O/C between 0.3 and 0.5) and unsaturated (and/or cyclic) in nature. Results from this study also highlight that mass spectra from HR-ToF-AMS measurements concerning primary emissions such as incense burning contain very useful information in the high m/z (>100) region about the chemical characteristics of those primary organic particles.

Copyright 2012 American Association for Aerosol Research     

Electrochemistry-electrospray ionization FT ICR mass spectrometry (EC ESI MS) of guanine–tyrosine and guanine–glutathione crosslinks formed on-line

Crosslinking of guanine with tyrosine and glutathione is studied by on-line electrochemistry electrospray ionization mass spectrometry (EC ESI MS) in the positive ion mode with a high resolution FT ICR mass spectrometer without the use of an external oxidizer in the sample. Dimeric adducts of guanine with tyrosine (m/z 331) and (m/z 333) and a dimer of guanine with glutathione (m/z 459) are detected in the mass spectra of guanine–tyrosine and guanine–glutathione mixtures in addition to dimers of guanine (m/z 303) and tyrosine (m/z 361) and (m/z 363) and glutathione dimers (m/z 613) and (m/z 615). Guanine tetramers (m/z 627) and tetramers of guanine with 1 or 2 tyrosines, but not with three tyrosines, were also identified in the mass spectra of guanine–tyrosine mixtures. Formation of radicals and other oxidation products during positive ion mode ESI can drive the formation of covalent dimer adducts of guanine with tyrosine and glutathione. When low EC cell voltage is applied in on-line EC ESI MS, changes in ion intensities reflect changes in the oxidation conditions and are more apparent for 2e, 2H⁺ than for the 1e, 1H⁺ oxidation processes. Efficient oxidation during ESI is indicated for analytes with low redox potentials.     

Separation of m-cresol from aromatic hydrocarbon and alkane using ionic liquids via hydrogen bond interaction

Low temperature coal tar contained a large amount of phenols, aromatic hydrocarbons and alkanes; the separation of phenols from coal tar has a great significance to the deep processing of coal tar. In this work, the separation of m-cresol from cumene and n-heptane by liquid–liquid extraction using ionic liquids (ILs) as extractants was studied. The suitable ILs were screened by conductor-like screening model for real solvents (COSMO-RS) model and the liquid–liquid phase equilibrium (LLE) experiments were to verify the accuracy of the screening results. The extraction conditions such as extraction time, extraction temperature and mass ratio of ILs to model oils were evaluated. An internal mechanism of the m-cresol extract by ILs was revealed by COSMO-RS calculation and FT-IR. The results showed that the selected ILs can extract m-cresol effectively from cumene and n-heptane, 1-ethyl-3-methylimidazolium acetate (emimCH₃COO) was the best extraction solvent. A hydrogen bond between anion of ILs and phenolic hydroxyl groups was observed. M-cresol in model oils could be extracted with extraction efficiencies up to 98.85% at an emimCH₃COO: model oils mass ratio of 0.5 and 298.15 K, emimCH₃COO could be regenerated and reused for 4 cycles without obvious decreases in extraction efficiency and extractant mass.     

Structural characterization of the oligomeric constituents of petroleum pitches

The separation of petroleum pitch into its oligomeric fractions via dense-gas extraction (DGE), followed by the application of both new and conventional analytical techniques to those fractions, has given us unique capabilities for identifying both the specific molecular structures that exist in petroleum pitches and their concentration. Specifically, pitch fractions containing 98% monomer or 97% dimer were isolated by DGE and characterized using MALDI, MALDI-PSD, and FD mass spectrometry (MS); and ¹H NMR, UV-Vis, and FT-IR spectroscopy. Results indicate that the molecular weight distribution (MWD) of the 98% monomer pitch fraction is approximately Gaussian, with the dominant species being methylated derivatives of the polycyclic aromatic hydrocarbons (PAH) benzofluorene (216.4 m/z), chrysene, (228.3 m/z), benzofluoranthene (252.3 m/z), and their isomers. The distribution of methyl substituents per molecule is also approximately Gaussian, with a maximum at 2. The MWD of the 97% dimer pitch fraction is also approximately Gaussian, and the most prevalent species (m/z = 454.6, 468.7, and 482.8) are consistent with condensation reactions of the most common monomer species with an accompanying loss of 4-6 hydrogens. As mesophase pitches that contain up to 25% dimer were previously identified, herein are proposed specific molecular structures that are significant constituents in mesophase pitch.     

Evaluation of a Method for Nitrotyrosine Site Identification and Relative Quantitation Using a Stable Isotope-Labeled Nitrated Spike-In Standard and High Resolution Fourier Transform MS and MS/MS Analysis

The overproduction of reactive oxygen and nitrogen species (ROS and RNS) can have deleterious effects in the cell, including structural and possible activity-altering modifications to proteins. Peroxynitrite is one such RNS that can result in a specific protein modification, nitration of tyrosine residues to form nitrotyrosine, and to date, the identification of nitrotyrosine sites in proteins continues to be a major analytical challenge. We have developed a method by which ¹⁵N-labeled nitrotyrosine groups are generated on peptide or protein standards using stable isotope-labeled peroxynitrite (O¹⁵NOO⁻), and the resulting standard is mixed with representative samples in which nitrotyrosine formation is to be measured by mass spectrometry (MS). Nitropeptide MS/MS spectra are filtered using high mass accuracy Fourier transform MS (FTMS) detection of the nitrotyrosine immonium ion. Given that the nitropeptide pair is co-isolated for MS/MS fragmentation, the nitrotyrosine immonium ions (at m/z = 181 or 182) can be used for relative quantitation with negligible isotopic interference at a mass resolution of greater than 50,000 (FWHM, full width at half-maximum). Furthermore, the standard potentially allows for the increased signal of nitrotyrosine-containing peptides, thus facilitating selection for MS/MS in a data-dependent mode of acquisition. We have evaluated the methodology in terms of nitrotyrosine site identification and relative quantitation using nitrated peptide and protein standards.     

Electrical properties of Sb and Cr-doped PbZrO3–PbTiO3–PbMg1/3Nb2/3O3 ceramics

The pyroelectric, dielectric and DC resistive properties of Sb and Cr-doped ceramics with a base composition of Pb(Mg_1/3Nb_2/3)_0.025(Zr_0.825Ti_0.175)_0.975O₃ have been studied. Sb doping has been shown to produce a linear reduction in Curie temperature (T_C=−22z+294 °C) with concentration (z) and to give an increase in pyroelectric coefficient from 250 to 310 μCm⁻² K⁻¹ for z increasing from 0 to 3 at.%. It also produces first a reduction and then an increase in both dielectric constant and loss, so that the 33 Hz pyroelectric figures of merit (FOM's) are as follows: F_V peaks at 3.8×10⁻² m² C⁻¹ and F_D peaks at 1.2×10⁻⁵ Pa^−1/2. The resistivity is increased substantially from 1.1×10¹¹ to ca 6×10¹¹ Ωm with 1 at.% Sb, thereafter changing little. The behaviour has been explained in terms of Sb acting as a donor ion, reducing oxygen vacancy concentrations up to 1 at.%, with conductivity dominated by hole hopping between traps (E_a=0.59±0.05 eV) that are not changed by the Sb doping. It is concluded that additions of higher levels of Sb do not produce electron-mediated hopping conduction. The Cr additions have no effect upon T_C, but reduce dielectric constant and loss, pyroelectric coefficient and resistivity at doping levels up to 3 at.%. The FOM F_V peaks at 3.6×10⁻² m² C⁻¹ and F_D at 1.9×10⁻⁵ Pa^−1/2. The behaviour of the electrical resistivity as a function of dopant level is shown to produce a linear ln(σ_o) vs z^−1/3 dependence (σ_o=DC conductivity), as would be expected for hole hopping conduction between Cr³⁺ sites, with an E_a=0.38±0.03 eV.     

Intramuscular Exposure to a Lethal Dose of Ricin Toxin Leads to Endothelial Glycocalyx Shedding and Microvascular Flow Abnormality in Mice and Swine

Ricin toxin isolated from the castor bean (Ricinus communis) is one of the most potent and lethal molecules known. While the pathophysiology and clinical consequences of ricin poisoning by the parenteral route, i.e., intramuscular penetration, have been described recently in various animal models, the preceding mechanism underlying the clinical manifestations of systemic ricin poisoning has not been completely defined. Here, we show that following intramuscular administration, ricin bound preferentially to the vasculature in both mice and swine, leading to coagulopathy and widespread hemorrhages. Increased levels of circulating VEGF and decreased expression of vascular VE-cadherin caused blood vessel impairment, thereby promoting hyperpermeability in various organs. Elevated levels of soluble heparan sulfate, hyaluronic acid and syndecan-1 were measured in blood samples following ricin intoxication, indicating that the vascular glycocalyx of both mice and swine underwent extensive damage. Finally, by using side-stream dark field intravital microscopy imaging, we determined that ricin poisoning leads to microvasculature malfunctioning, as manifested by aberrant blood flow and a significant decrease in the number of diffused microvessels. These findings, which suggest that glycocalyx shedding and microcirculation dysfunction play a major role in the pathology of systemic ricin poisoning, may serve for the formulation of specifically tailored therapies for treating parenteral ricin intoxication.     

Comments on “Investigation of Ethylene Oxide on Clean and Oxygen-Covered Ag(110) Surfaces”

This letter is a re-examination of the ethylene oxide (EO) temperature programmed desorption (tpd) peak shapes (reported in references 1 and 2) which were obtained by tpd after having adsorbed EO at 250 K on to Ag(110) and Ag(111) surfaces. In these papers, the peaks were deemed to originate from a unimolecular rearrangement of an adsorbed oxametallacycle, producing EO, which desorbed on formation. Consequently, on the basis of this thesis, the activation energy of the composite process of internal rearrangement of the oxametallacycle and desorption of EO was determined by solution of the first order Redhead equation [3] at the peak maximum temperature, using an assumed value of 10¹³ s^?1 for the desorption pre-exponential term. The conclusions of this re-examination are that the m/z = 29 desorption peaks shown in Fig. 1 derive from a second order surface reaction of an adsorbed O atom and adsorbed ethylene molecule and that this is the rate determining step in the desorption of EO. An important corollary of these conclusions is that an oxametallacycle is not involved in the ethylene epoxidation reaction coordinate as the papers suggest.

Chromatographic separations enabling the structural characterisation of heavy petroleum residues

Two petroleum residues from European crudes have been fractionated using solvent (heptane) separation and column chromatography. The residues and the separated fractions have been characterised by size exclusion chromatography (SEC) and by UV-fluorescence spectroscopy (UV-F). Matrix assisted laser desorption/ionisation-mass spectrometry of the whole residues and the heptane insoluble fractions indicated that the bulk of the residues covered the mass range m/z 300-2000, while the heptane insolubles (1-2% of the whole) contained material in the mass range from about m/z 300 to 10?000. The upper mass ranges indicated by SEC using polystyrene standards were higher; the earliest eluting material from both distillation residues eluted at times corresponding to polystyrene standards of MMs above 1.85 million u. Possible reasons for the different observations are given. Data from UV-F suggests that the heptane solubility separation method was the most successful for the separation of the largest molecular mass and also probably the most polar materials in these residues. However, all three fractionation methods produced similar trends, showing greater polarity of the fractions to correlate with increasing molecular mass. The shift of maximum intensity of fluorescence towards longer wavelengths (in UV-fluorescence) with increasing molecular size, as indicated by SEC, strongly suggests that the fluorescing molecules are large rather than aggregates of small molecules. Differences in comparison with American petroleum residues can be observed.     

Synthesis, mass spectrometry, and nuclear magnetic resonance characterization of Di-guerbet esters

Several Di-Guerbet esters (DGE) suitable for lubricant applications were synthesized from branched Guerbet alcohols and Guerbet acids. The mass spectra of DGE under electron-ionization and positive chemical-ionization (PCI) conditions were recorded. Gas chromatography-mass spectrometry, especially in PCI mode with methane as reagent gas, is an effective method for analyzing DGE. In methane positive chemical-ionization mass spectrometry, the DGE give molecular ion peaks. In both PCI and EI modes, some other characteristic ions including up to four McLafferty rearrangement products with high m/z are observed. Thus identification of both hydrocarbon moieties is possible. The DGE were also characterized by ¹H-and ¹³C nuclear magnetic resonance. Deceased.     

Mass Spectra of Unlabeled and Isotopically Labeled Hexamethylene Triperoxide Diamine (HMTD)

Electron impact (EI) mass spectra of unlabeled and ¹³C/¹⁵N labeled hexamethylene triperoxide diamine were obtained using a direct insertion probe. The most prominent peaks were the molecular ions (m/z 208 and m/z 216, respectively). An EI fragmentation pathway is proposed based on the mass spectral evidence.     

New isopolyoxovanadate ions identified by electrospray mass spectrometry

Ammonium metavanadate in aqueous solution at pH 4.5 displays in electrospray mass spectrometry experiments the presence of the two series of anions [H_xV_yO_z]⁻ (x=0, 1; y=1–9; z=3–23) and [H_xV_yO_z]²⁻ (x=0, 1; y=3–17; z=9–44) as well as [H₂VO₄]⁻, [V₁₀O₂₈]⁶⁻ and [H₅V₁₀O₂₈]⁻ ions. Further, the cation series [H_m+1(VO₃)_m]⁺ (m=1–6), [H_m−1V_mO_3m−1]⁺ (m=4–10) and [H_m−3V_mO_3m−2]⁺ (m=6–11) are observed. The series of protonated and unprotonated anions differ by {V₂O₅} units, the formal building block in these clusters. A range of polyoxovanadates not previously reported have been observed.     

HPLC separation,NMR and QTOF/MS/MS structure elucidation of a prominent nitric oxide donor agent based on an isomeric composition of a nitrosyl ruthenium complex

A new and promising nitrosyl ruthenium complex, [Ru(NO)(bdqi-COOH)(terpy)](PF₆)₃, bdqi-COOH is 3,4-diiminebenzoic acid and terpy is 2,2′-terpyridine, has been synthesized as a NO donor agent. The procedure used for [Ru(NO)(bdqi-COOH)(terpy)](PF₆)₃ synthesis has, apparently, yielded the formation of two isomers in which the ligand bdqi-COOH appears to be coordinated in its reduced form (bdcat-COOH), which could have differences in their pharmacological properties. Therefore, it was intended to separate the two possible isomers by high-performance liquid chromatography (HPLC) and to characterize them by high resolution mass spectrometry (QTOF MS) and by magnetic nuclear resonance spectroscopy (NMR). The results obtained by MS showed that the ESI-MS mass spectra of both HPLC column fractions, e.g. peak 1 and peak 2, are essentially equal, showing that both isomers display nearly identical gas-phase behavior with clusters of isotopologue ions centered at m/z 573, m/z 543 and m/z 513. Regarding the NMR analysis, the results showed that the positional isomerism is located in the bdqi-COOH ligand. From the observed results it can be concluded that the synthesis procedure that has been used results in the formation of two [Ru(terpy)(bdqi-COOH)NO](PF₆)₃ isomers.     

Electrochemical reduction and oxidation pathways for Reactive Black 5 dye using nickel electrodes in divided and undivided cells

The cathodic reduction and anodic OH-mediated oxidation of the azo dye Reactive Black 5 (RB5) have been studied potentiostatically by using undivided and divided cells with a Ni-polyvinylchloride (Ni-PVC) composite cathode and a Ni wire mesh anode. Solutions of 50–100 cm³ of 20–80 mg dm^?3 RB5 in 0.1 mol dm^?3 KOH were degraded to assess the effect of electrolysis time and electrode potentials on the infrared and absorbance spectra, as well as on the decay of the total organic carbon and chemical oxygen demand. Reversed-phase high performance liquid chromatography (RP-HPLC) with ion-pairing and diode array detection (ion pair chromatography), along with coupling to tandem mass spectrometry (LC–MS/MS), were used for the identification of the aromatic degradation by-products and monitoring their time course. These analyses revealed the progressive conversion of the RB5 dye to simpler molecules with m/z 200, 369.5 and 547 under the direct action of the electron at the cathode and the formation of polar compounds such as alkylsulfonyl phenol derivatives with m/z 201, 185 and 171 by the OH mediation at the anode. From these results, the electrochemical reduction and oxidation pathways for the RB5 dye were elucidated.     

Synthesis of heterofullerene using a direct BN substitution reaction of fullerene

A heterofullerene in which carbon atoms of the fullerene cage are substituted by heteroatoms (boron and nitrogen) was synthesized by BN substitution reaction of fullerene C₆₀ upon irradiation with a KrF excimer laser at room temperature. The products were purified by a high performance liquid chromatography and analyzed with a double focusing mass and mass/mass spectrometer, revealing that BNC₅₈ (m/z 721) was formed. The existence of boron and nitrogen in the product was confirmed by X-ray photoelectron spectroscopy and ¹³C NMR analyses. Moreover, ¹¹B NMR spectrum of the sample indicated the existence of BN bond in the compound.