@article {ANIE:ANIE201406258,
	title = {An Organotrifluoroborate for Broadly Applicable One-Step 18F-Labeling},
	journal = {Angewandte Chemie International Edition},
	volume = {53},
	number = {44},
	year = {2014},
	pages = {11876{\textendash}11880},
	publisher = {WILEY-VCH Verlag},
	abstract = {A new zwitterionic organotrifluoroborate is appended to three radiosynthons that afford undergo facile bioconjugation to several clinically relevant peptides and one enzyme inhibitor. Molecularly complex bioconjugates are 18F-labeled in a single aqueous step in rapid time (<15 min) without HPLC purification to afford tracers in good yields (>200 mCi, 20{\textendash}40 \%) at high specific activity (>=3 Ci/μmol) and at >98 \% purity. PET imaging shows in vivo stability and tumor uptake.},
	keywords = {18F-labeling, bioconjugation, click chemistry, PEPTIDES, PET imaging},
	issn = {1521-3773},
	doi = {10.1002/anie.201406258},
	url = {http://dx.doi.org/10.1002/anie.201406258},
	author = {Liu, Zhibo and Pourghiasian, Maral and Radtke, Mark Alex and Lau, Joseph and Pan, Jinhe and Dias, Gemma M. and Yapp, Donald and Lin, Kuo-Shyan and B{\'e}nard, Francois and Perrin, David M.}
}
@article {2396,
	title = {Binding and Uptake of RGD-Containing Ligands to Cellular alpha(v)beta(3) Integrins},
	journal = {International Journal of Peptide Research and Therapeutics},
	volume = {15},
	number = {1},
	year = {2009},
	note = {ISI Document Delivery No.: 430WTTimes Cited: 2Cited Reference Count: 34Cressman, Sonya Sun, Ying Maxwell, E. Jane Fang, Ning Chen, David D. Y. Cullis, Pieter R.},
	month = {Mar},
	pages = {49-59},
	type = {Article},
	abstract = {The cyclic peptide, cRGDf[N(me)]V, binds to the alpha(v)beta(3) integrin and can disrupt binding of the integrin to its natural ligands in the extracellular matrix. In this work, the ability of a water-soluble, fluorescently labeled variant of the RGD-containing peptide (cRGDfK-488) to bind to integrins on human umbilical vascular endothelial cells (HUVEC) and subsequently undergo endocytosis was characterized. This information was compared to the binding and uptake properties of an alpha(v)beta(3) integrin-specific monoclonal antibody, LM609X. The specificity of the RGD-containing peptide is assessed by comparison with control peptide that does not bind to the alpha(v)beta(3) integrin, cRADfK-488. Using a high purity construct, it is shown that the RGD ligand exhibits dissociation constants in the micromolar range whereas LM609X exhibits dissociation constants in the nanomolar range. However, the RGD ligand showed greater uptake following incubation at temperatures which permit endocytosis. A 7.4-fold increase in uptake of the RGD peptide was observed following a 1 h incubation with HUVEC at 37 degrees C (an endocytosis permissive temperature), as compared to that at 4 degrees C (an endocytosis prohibitive temperature). In contrast, only a 1.9-fold increase in cell-associated fluorescence was observed for similar incubations with LM609X. Results from fluorescence microscopy supports the notion that the RGD peptide is rapidly endocytosed at 37 degrees C as compared to LM609X. These results are discussed with regard to previous work indicating that RGD ligands enter cells by integrin-independent pathways. These studies provide well-controlled measures of how RGD ligands stimulate endocytosis. This may be of considerable interest for intracellular delivery of ligand-associated drugs in anti-angiogenic applications.},
	keywords = {alpha(v)beta(3) integrins, ALPHA-V-BETA-3, ANGIOGENESIS, ANTAGONISTS, ANTITUMOR EFFICACY, CELLS, Endocytosis, EXPRESSION, IN-VIVO, PEPTIDES, RGD, TARGETED DRUG-DELIVERY, TUMOR VASCULATURE},
	isbn = {1573-3149},
	url = {<Go to ISI>://000265022900007},
	author = {Cressman, S. and Sun, Y. and Maxwell, E. J. and Fang, N. and Chen, D. D. Y. and Cullis, P. R.}
}
@article {2575,
	title = {An electropneumatic-heated nebulizer for enhancing spray ionization in PhotoSpray atmospheric pressure photoionization sources for liquid chromatography/mass spectrometry},
	journal = {Rapid Communications in Mass Spectrometry},
	volume = {23},
	number = {21},
	year = {2009},
	note = {ISI Document Delivery No.: 514YATimes Cited: 1Cited Reference Count: 30Robb, Damon B. Blades, Michael W.},
	month = {Nov},
	pages = {3394-3400},
	type = {Article},
	abstract = {We introduce a novel electropneumatic-heated nebulizer (EPn-HN), incorporating an electrified internal pneumatic nebulizer, to enhance the yield of sprayed ions from PhotoSpray (TM) atmospheric pressure photoionization (APPI) sources for liquid chromatography/mass spectrometry (LC/MS). Spray ionization from the pneumatic-heated nebulizers used in APPI sources provides a supplemental, complementary ionization method to be used for involatile and thermally labile compounds, otherwise intractable to APPI. Details of the construction and operation of the EPn-HN device are provided. The performance of the EPn-HN is demonstrated using two model compounds: substance P, a peptide used as a standard in studies of ion fragmentation mechanisms, and aztreonam, a thermally labile antibiotic. At the optimum voltage for spray ionization, improvements in sensitivity of two orders of magnitude are obtained relative to when the sprayer is grounded, the conventional case. Since both substance P and aztreonam cannot be detected using the APPI method alone, the results demonstrate how spray ionization from the EPn-HN may be used to extend the range of compounds amenable to PhotoSpray sources. Copyright (C) 2009 John Wiley \& Sons, Ltd.},
	keywords = {CHEMICAL-IONIZATION, ELECTROSPRAY, PEPTIDES, RESIDUES, TANDEM MASS-SPECTROMETRY},
	isbn = {0951-4198},
	url = {<Go to ISI>://000271431500006},
	author = {Robb, D. B. and Blades, M. W.}
}
@article {2648,
	title = {Implementation of a data repository-driven approach for targeted proteomics experiments by multiple reaction monitoring},
	journal = {Journal of Proteomics},
	volume = {72},
	number = {5},
	year = {2009},
	note = {ISI Document Delivery No.: 478RATimes Cited: 5Cited Reference Count: 30Walsh, Geraldine M. Lin, Shujun Evans, Daniel M. Khosrovi-Eghbal, Arash Beavis, Ronald C. Kast, Juergen},
	month = {Jul},
	pages = {838-852},
	type = {Article},
	abstract = {Multiple reaction monitoring (MRM), commonly employed for the mass spectrometric detection of small molecules, is rapidly gaining ground in proteomics. Its high sensitivity and specificity makes this targeted approach particularly useful when sample throughput or proteome coverage limits global studies. Existing tools to design MRM assays rely exclusively on theoretical predictions, or combine them with previous observations on the same type of sample. The additional mass spectrometric experimentation this requires can pose significant demands on time and material. To overcome these challenges, a new MRM worksheet was introduced into The Global Proteome Machine database (GPMDB) that provided all of the information needed to design MRM transitions based solely on archived observations made by other researchers in previous experiments. This required replacing the precursor ion intensity by the number of peptide observations, which proved to be an adequate substitute if peptides did not occur in multiple forms. While the absence of collision energy information proved largely inconsequential, successful prediction of unique transitions depended on the type of fragment ion involved. The design of MRM assays for iTRAQ-labeled tryptic peptides obtained from human platelet proteins demonstrated the usefulness of the MRM worksheet also for quantitative applications. This workflow, which relies exclusively on experimental observations stored in data repositories, therefore represents an attractive alternative for the prediction of MRM transitions prior to experimental validation and optimization. (C) 2008 Elsevier B.V. All rights reserved.},
	keywords = {ABSOLUTE, Data repository, HIGH-SENSITIVITY, LIBRARIES, Multiple reaction monitoring, PEPTIDES, PHOSPHORYLATION, PLASMA-PROTEINS, PLATELETS, PREDICTION, PROTEIN IDENTIFICATION, PROTEOMICS, QUANTIFICATION, SHOTGUN PROTEOMICS, Tandem mass spectrometry, TANDEM MASS-SPECTROMETRY, Targeted},
	isbn = {1874-3919},
	url = {<Go to ISI>://000268604400013},
	author = {Walsh, G. M. and Lin, S. and Evans, D. M. and Khosrovi-Eghbal, A. and Beavis, R. C. and Kast, J.}
}
@article {2661,
	title = {Rolloamides A and B, Cytotoxic Cyclic Heptapeptides Isolated from the Caribbean Marine Sponge Eurypon laughlini},
	journal = {Journal of Natural Products},
	volume = {72},
	number = {7},
	year = {2009},
	note = {ISI Document Delivery No.: 479MVTimes Cited: 3Cited Reference Count: 14Williams, David E. Yu, Ker Behrisch, Hans W. Van Soest, Rob Andersen, Raymond J.},
	month = {Jul},
	pages = {1253-1257},
	type = {Article},
	abstract = {Two cyclic heptapeptides, rolloamides A (1) and B (2), have been isolated from the Dominican marine sponge Eurypon laughlini. The structures of 1 and 2 were elucidated by a combination of spectroscopic analyses and chemical degradation. Rolloamide A (1), which was found to exist as two distinct conformers in C5D5N, exhibits growth suppressive activity against a panel of histologically diverse cancer cell lines.},
	keywords = {NATURAL-PRODUCTS, OCTAPEPTIDE, PEPTIDES, PORIFERA, PROLINE, STYLOTELLA-AURANTIUM},
	isbn = {0163-3864},
	url = {<Go to ISI>://000268664500006},
	author = {Williams, D. E. and Yu, K. and Behrisch, H. W. and Van Soest, R. and Andersen, R. J.}
}
@article {2183,
	title = {Intraannular Savige-Fontana reaction: One-step conversion of one class of monocyclic peptides into another class of bicyclic peptides},
	journal = {Chemistry-a European Journal},
	volume = {14},
	number = {11},
	year = {2008},
	note = {ISI Document Delivery No.: 291XITimes Cited: 1Cited Reference Count: 34May, Jonathan P. Perrin, David M.},
	pages = {3404-3409},
	type = {Article},
	abstract = {Cyclisation and cross-linking strategies are important for the synthesis of cyclic and bicyclic peptides. These macrolactams are of great interest due to their increased biological activity compared to linear analogues. Herein, we describe the synthesis of a cyclic peptide containing an Hpi toxicophore, reminiscent of phakellistatins and omphalotins. The first intraannular cross-linking of such a peptide is then presented: using neat TFA to catalyse a Savige-Fontana tryptathionylation, the Hpi-containing peptide is converted to a bicyclic amatoxin analogue. As such, this methodology represents an efficient cyclisation method for cross-linking peptides and exposes a heretofore unrealised relationship between two different classes of peptide natural products. This finding increases the degree of potential chemical space for library generation.},
	keywords = {2-CHLOROTRITYL CHLORIDE, 2-THIOETHER DERIVATIVES, amatoxin, ANALOGS, CROSS-LINKING, CYSTEINE SULFHYDRYL-GROUPS, ILE3-AMANINAMIDE, indole, ISOPHAKELLISTATIN-3, natural products, OXIDATION, PEPTIDES, PHALLOTOXINS, RNA POLYMERASE-II, TRYPTOPHAN},
	isbn = {0947-6539},
	url = {<Go to ISI>://000255230200019},
	author = {May, J. P. and Perrin,David M.}
}
@article {2182,
	title = {Synthesis, characterisation, and in vitro evaluation of Pro(2)-Ile(3)-S-deoxo-amaninamide and Pro(2)-D-allo-Ile(3)-S-deoxo-amaninamide: Implications for structure-activity relationships in amanitin conformation and toxicity},
	journal = {Chemistry-a European Journal},
	volume = {14},
	number = {11},
	year = {2008},
	note = {ISI Document Delivery No.: 291XITimes Cited: 0Cited Reference Count: 39May, Jonathan P. Fournier, Pierre Patrick, Brian O. Perrin, David M.},
	pages = {3410-3417},
	type = {Article},
	abstract = {The amatoxins are a family of toxic bicyclic peptides that inhibit RNA polymerase II. Herein we discuss an improved synthesis of these compounds from easily obtainable amino acids by means of a solid-phase methodology. Interestingly, we obtained two products of the same mass following our final macrocyclisation, relating to a similar distribution of products described in some previous reports. One of these products was the desired amatoxin; Pro(2)-Ile(3)-S-deoxo-amaninamide 1b. The other compound, after thorough investigation, was confirmed to be the epimer Pro(2)-D-allo-Ile(3)-S-deoxo-amaninamide la, not an atropisomer structure as previously suggested in syntheses of related amanitin analogues. Crystallographic data of la confirms the presence of a beta II-turn, rather than a PI-turn common to the natural toxin and 1b. This difference explains the large variation in CD spectra, although it seems to have relatively little effect on the bioactivity in vitro. These data provide new insights into the bicyclic amatoxin structure.},
	keywords = {ALPHA-AMANITIN, amatoxin, atropisomerism, circular dichroism, CRYSTALLINE STATE, CYCLIZATION, CYSTEINE SULFHYDRYL-GROUPS, EPIMERIZATION, MOLECULAR-STRUCTURE, PEPTIDES, RESOLUTION, RNA-POLYMERASE-II, SERIES, TOXIN BETA-AMANITIN, transcription},
	isbn = {0947-6539},
	url = {<Go to ISI>://000255230200020},
	author = {May, J. P. and Fournier, P. and Patrick, B. O. and Perrin,David M.}
}
@article {2287,
	title = {Toward [F-18]-labeled aryltrifluoroborate radiotracers: In vivo positron emission tomography imaging of stable aryltrifluoroborate clearance in mice},
	journal = {Journal of the American Chemical Society},
	volume = {130},
	number = {36},
	year = {2008},
	note = {ISI Document Delivery No.: 344TPTimes Cited: 15Cited Reference Count: 35Ting, Richard Harwig, Curtis auf dem Keller, Ulrich McCormick, Siobhan Austin, Pamela Overall, Christopher M. Adam, Michael J. Ruth, Thomas J. Perrin, David M.},
	month = {Sep},
	pages = {12045-12055},
	type = {Article},
	abstract = {The use of a boronic ester as a captor of aqueous [F-18]-fluoride has been previously suggested as a means of labeling biomolecules in one step for positron emission tomography (PET) imaging. For this approach to be seriously considered, the [F-18]-labeled trifluoroborate should be humorally stable such that it neither leaches free [F-18]-fluoride to the bone nor accumulates therein. Herein, we have synthesized a biotinylated boronic ester that is converted to the corresponding trifluoroborate salt in the presence of aqueous [F-18]-fluoride. In keeping with its in vitro aqueous kinetic stability at pH 7.5, the trifluoroborate appears to clear in vivo quite rapidly to the bladder as the stable trifluoroborate salt with no detectable leaching of free [F-18]-fluoride to the bone. When this labeled biotin is preincubated with avidin, the pharmacokinetic clearance of the resulting complex is visibly altered. This work validates initial claims that boronic esters are potentially useful as readily labeled precursors to [F-18]-PET reagents.},
	keywords = {apoptosis, BIODISTRIBUTION, CANCER, DESIGN, F-18, MICROPET, NO-CARRIER, PEPTIDES, PET, STABILITY},
	isbn = {0002-7863},
	url = {<Go to ISI>://000258950500044},
	author = {Ting, R. and Harwig, C. and auf dem Keller, U. and McCormick, S. and Austin, P. and Overall, C. M. and Adam,Michael J. and Ruth, T. J. and Perrin,David M.}
}
@article {2287,
	title = {Toward [F-18]-labeled aryltrifluoroborate radiotracers: In vivo positron emission tomography imaging of stable aryltrifluoroborate clearance in mice},
	journal = {Journal of the American Chemical Society},
	volume = {130},
	number = {36},
	year = {2008},
	note = {ISI Document Delivery No.: 344TPTimes Cited: 15Cited Reference Count: 35Ting, Richard Harwig, Curtis auf dem Keller, Ulrich McCormick, Siobhan Austin, Pamela Overall, Christopher M. Adam, Michael J. Ruth, Thomas J. Perrin, David M.},
	month = {Sep},
	pages = {12045-12055},
	type = {Article},
	abstract = {The use of a boronic ester as a captor of aqueous [F-18]-fluoride has been previously suggested as a means of labeling biomolecules in one step for positron emission tomography (PET) imaging. For this approach to be seriously considered, the [F-18]-labeled trifluoroborate should be humorally stable such that it neither leaches free [F-18]-fluoride to the bone nor accumulates therein. Herein, we have synthesized a biotinylated boronic ester that is converted to the corresponding trifluoroborate salt in the presence of aqueous [F-18]-fluoride. In keeping with its in vitro aqueous kinetic stability at pH 7.5, the trifluoroborate appears to clear in vivo quite rapidly to the bladder as the stable trifluoroborate salt with no detectable leaching of free [F-18]-fluoride to the bone. When this labeled biotin is preincubated with avidin, the pharmacokinetic clearance of the resulting complex is visibly altered. This work validates initial claims that boronic esters are potentially useful as readily labeled precursors to [F-18]-PET reagents.},
	keywords = {apoptosis, BIODISTRIBUTION, CANCER, DESIGN, F-18, MICROPET, NO-CARRIER, PEPTIDES, PET, STABILITY},
	isbn = {0002-7863},
	url = {<Go to ISI>://000258950500044},
	author = {Ting, R. and Harwig, C. and auf dem Keller, U. and McCormick, S. and Austin, P. and Overall, C. M. and Adam,Michael J. and Ruth, T. J. and Perrin,David M.}
}
@article {1414,
	title = {Multiple neutral loss monitoring (MNM): A multiplexed method for post-translational modification screening},
	journal = {Journal of the American Society for Mass Spectrometry},
	volume = {17},
	number = {3},
	year = {2006},
	note = {ISI Document Delivery No.: 021SETimes Cited: 11Cited Reference Count: 20},
	month = {Mar},
	pages = {307-317},
	type = {Article},
	abstract = {Post-translational modifications of proteins are involved in determining the activity of proteins and are essential for proper protein function. Current mass spectrometric strategies require one to specify a particular type of modification, in some cases also a particular charge state of a protein or peptide that is to be studied before the actual analysis. Due to these requirements, most of the modifications on proteins are not considered in such an experiment and, thus, a series of similar analyses need to be performed to ensure a more extensive characterization. A novel scan strategy has been developed, multiple neutral loss monitoring (MNM), allowing for the comprehensive screening of post-translational modifications (PTM) on proteins that fragment as neutral losses in a mass spectrometer. MNM method parameters were determined by performing product ion scans on a number of modified peptides over a range of collision energies, providing neutral loss energy profiles and optimal collision energies (OCE) for each modification, supplying valuable information pertaining to the fragmentation of these modifications and the necessary parameters that would be required to obtain the best analysis. As the optimal collision energy was highly dependent on the type of modification and the charge state of the peptide, the MNM scan was operated with a collision energy gradient. Autocorrelation analyses identified the type of modification, and convolution mapping analyses identified the associated peptide. The MNM scan with the new collision energy parameters was successfully applied to a mixture of four modified peptides in a BSA digest. The implementation of this technique will allow for comprehensive screening of all modifications that fragment as neutral losses.},
	keywords = {COLLISION-INDUCED DISSOCIATION, PEPTIDES, PROTEIN-PHOSPHORYLATION, PROTEOMIC ANALYSIS, SCAN, TANDEM MASS-SPECTROMETRY},
	isbn = {1044-0305},
	url = {<Go to ISI>://000236004700004},
	author = {Hoffman, M. D. and Sniatynski, M. J. and Rogalski, J. C. and Le Blanc, J. C. Y. and Kast, J.}
}
@article {959,
	title = {Efficient synthesis of isotopically pure isotope-coded affinity tagging reagents},
	journal = {Bioconjugate Chemistry},
	volume = {15},
	number = {1},
	year = {2004},
	note = {ISI Document Delivery No.: 766UDTimes Cited: 7Cited Reference Count: 24},
	month = {Jan-Feb},
	pages = {224-230},
	type = {Article},
	abstract = {Synthesis of an isotopically pure d(8)-ICAT linker, N- [(5,5,6,6,8,8 9,9-H-2)-13-biotinamido-4,7,10-trioxatridecanyl] tert-butyloxy carbamide (12), has been achieved in seven steps with an overall yield of 33\%. Conjugation of exchange-inert d(4)-starting materials by classic etherification reaction yielded a pure synthon, carrying eight deuteriums that remained exchange-inert throughout subsequent reactions. This modified synthesis constitutes a significant improvement to the reported syntheses of "heavy" ICAT reagent in terms of expense, yield, and isotopic retention. This synthesis is easily adapted to incorporate additional deuterium atoms and is equally applicable for incorporation of either C-13 and/or O-18. In addition, this synthesis allows for the introduction of different orthogonal functionalities and provides for a high yielding series of differentially encoded ICAT tags.},
	keywords = {GEL-ELECTROPHORESIS, IONIZATION MASS-SPECTROMETRY, LIQUID-CHROMATOGRAPHY, PEPTIDES, PROTEINS, PROTEOME ANALYSIS, TAGS},
	isbn = {1043-1802},
	url = {<Go to ISI>://000188393200027},
	author = {Patel, A. and Perrin,David M.}
}
@article {769,
	title = {Spirastrellolide A, an antimitotic macrolide isolated from the Caribbean Marine Sponge Spirastrella Coccinea},
	journal = {Journal of the American Chemical Society},
	volume = {125},
	number = {18},
	year = {2003},
	note = {ISI Document Delivery No.: 675FLTimes Cited: 52Cited Reference Count: 14},
	month = {May},
	pages = {5296-5297},
	type = {Article},
	keywords = {AGENTS, PACLITAXEL, PEPTIDES, TUBULIN},
	isbn = {0002-7863},
	url = {<Go to ISI>://000182682700025},
	author = {Williams, D. E. and Roberge, M. and Van Soest, R. and Andersen, R. J.}
}
@article {5189,
	title = {Collision-induced dissociation of bradykinin ions in the interface region of an ESI-MS},
	journal = {Journal of the American Society for Mass Spectrometry},
	volume = {12},
	number = {7},
	year = {2001},
	note = {ISI Document Delivery No.: 447HHTimes Cited: 17Cited Reference Count: 42},
	month = {Jul},
	pages = {772-779},
	type = {Article},
	abstract = {By applying different electric field strengths to the orifice-skimmer region of an electrospray ionization mass spectrometer, the rate of dissociation can be varied based on the amount of infernal energy acquired by an ion through collisions: with the curtain gas molecules. Both the Arrhenius equation and Rice-Ramsperger-Kassel (RRK) theory can be used to predict the rate of dissociation of internally excited molecules. A previously determined model for collision-induced dissociation is tested by comparison of predicted and experimentally observed orifice-skimmer potential differences for dissociation of ions. The rate of collision-induced dissociation of bradykinin ions is determined by monitoring the fragments produced in a mass spectrometer. The semi-quantitative model is found to yield effective predictions when accurate Arrhenius and RRK parameters are utilized. (C) 2001 American Society for Mass Spectrometry.},
	keywords = {ACTIVATION, CYTOCHROME-C, ELECTROSPRAY-IONIZATION, GAS-PHASE, IDENTIFICATION, INFRARED RADIATIVE DISSOCIATION, IONIZATION MASS-SPECTROMETRY, MOLECULES, PEPTIDES, PROTEIN IONS},
	isbn = {1044-0305},
	url = {<Go to ISI>://000169565500002},
	author = {Schneider, B. B. and Douglas, D. J. and Chen, D. D. Y.}
}
@article {5231,
	title = {[ReO(N2O2)X] complexes: "4+1"?},
	journal = {Inorganic Chemistry},
	volume = {40},
	number = {18},
	year = {2001},
	note = {ISI Document Delivery No.: 466JNTimes Cited: 3Cited Reference Count: 36},
	month = {Aug},
	pages = {4623-4626},
	type = {Article},
	abstract = {{[ReO(ppme)X] (where ppme(2-) is 2,5-diazo-N,N {\textquoteright} -dimethylhexyl-1,6-bis(phenylphosphinate)},
	keywords = {CHEMISTRY, OXO-COMPLEXES, PEPTIDES, RADIOPHARMACEUTICALS, RHENIUM(V), SCHIFF-BASE LIGANDS, STABILITY, TC-99M, TECHNETIUM COMPLEXES, X-ray structures},
	isbn = {0020-1669},
	url = {<Go to ISI>://000170642600019},
	author = {Xu, L. and Lowe, M. P. and Rettig, S. J. and Orvig, Chris}
}
@article {4920,
	title = {Electrospray ionization of alkali and alkaline earth metal species. Electrochemical oxidation and pH effects},
	journal = {Journal of Mass Spectrometry},
	volume = {35},
	number = {8},
	year = {2000},
	note = {ISI Document Delivery No.: 347MUTimes Cited: 7Cited Reference Count: 49},
	month = {Aug},
	pages = {981-989},
	type = {Article},
	abstract = {The utility of electrospray ionization mass spectrometry (ESI-MS) for characterizing dissolved metal species has generated considerable interest in the use of this technique for metal speciation, However, the development of accurate speciation methods based on ESI-R;IS requires a detailed understanding of the mechanisms by which dissolved metal species are ionized during electrospray. We report how the analysis of alkali and alkaline earth metal species pro,ides new information about some of the processes that affect electrospray ion yield. Selected metal ions and organic ligands were combined in 50:50 water-acetonitrile buffered with acetic acid or ammonium acetate and analyzed by flow injection ESI-MS using mild electrospray conditions. Species formed by alkali metal ions with thiol and oxygen-donating ligands were detected in acidic and neutral pH solutions. Electrochemical oxidation of N,N-diethyldithiocarbamate and glutathione during electrospray was indicated by detection of the corresponding disulfides as protonated or alkali metal species, The extent of ligand oxidation depended on solution pH and the dissociation constant of the thiol group, Tandem mass spectrometric experiments suggested that radical cations such as [NaL](+.) (where L = N,N -diethyldithiocarbamate) can be generated by in-source fragmentation of disulfide species. Greater complexation of alkali metals at neutral pH tvas indicated by a corresponding decrease in the relative abundance of the free metal ion, The number of alkali metal ions bound by glutathione and phthalic acid also increased with increasing pH, in accordance with thermodynamic equilibrium theory. Alkaline earth metal species were detected only in acidic solutions, the absence of 8-hydroxyquinoline complexes being attributed to their relative instability and subsequent dissociation during electrospray, Hence, accurate speciation by ESI-MS depends on experimental conditions and the intrinsic properties of each analyte, Copyright (C) 2000 John Wiley \&; Sons, Ltd.},
	keywords = {cell, COMPLEXES, electrochemical oxidation, ELECTROPHORESIS, electrospray ionization, ION-TRAP, MASS-SPECTROMETRY, metal speciation, OLIGONUCLEOTIDES, PEPTIDES, pH effects, PROTEINS, STOICHIOMETRY, thiol ligands, WATER},
	isbn = {1076-5174},
	url = {<Go to ISI>://000088934400006},
	author = {Ross, A. R. S. and Ikonomou, M. G. and Orians, K. J.}
}
@article {4753,
	title = {An interface with a linear quadrupole ion guide for an electrospray-ion trap mass spectrometer system},
	journal = {Analytical Chemistry},
	volume = {72},
	number = {22},
	year = {2000},
	note = {ISI Document Delivery No.: 374LNTimes Cited: 30Cited Reference Count: 41},
	month = {Nov},
	pages = {5647-5654},
	type = {Article},
	abstract = {A new ion sampling interface for an electrospray ionization 3D ion trap mass spectrometer system is described. The interface uses linear rf quadrupoles as ion guides and ion traps to enhance the performance of the 3D trap. Trapping ions in the linear quadrupoles is demonstrated to improve the duty cycle of the system. Dipolar excitation of ions trapped in a linear quadrupole is used to eject unwanted ions, A resolution of ejection of up to 254 is demonstrated for protonated reserpine ions (m/z 609.3), A composite waveform with a notch in frequency space is used to eject a wide range of matrix ions and to isolate trace analyte ions in a linear quadrupole before ions are injected into the 3D trap. This is useful to overcome space charge problems in the 3D trap caused by excess matrix ions. For trace reserpine in a 500-fold molar excess of poly(propylene glycol) (PPG), it is demonstrated that the resolution and sensitivity of the 3D trap can be increased dramatically with ejection of the excess PPG matrix ions. In comparison to ejection of matrix ions in the 3D trap with a similar broad-band waveform, a ii-fold increase in sensitivity with a 7 times shorter acquisition time was achieved.},
	keywords = {accumulation, ACCURACY, DIGESTS, DISSOCIATION, FILTERED NOISE FIELD, INJECTION, IONIZATION, PEPTIDES, PROTEINS, storage},
	isbn = {0003-2700},
	url = {<Go to ISI>://000165346800018},
	author = {Cha, B. C. and Blades, M. W. and Douglas, D. J.}
}
@article {3874,
	title = {Total synthesis of (-)-hemiasterlin, a structurally novel tripeptide that exhibits potent cytotoxic activity},
	journal = {Tetrahedron Letters},
	volume = {38},
	number = {3},
	year = {1997},
	note = {ISI Document Delivery No.: WC807Times Cited: 44Cited Reference Count: 16},
	month = {Jan},
	pages = {317-320},
	type = {Article},
	abstract = {The total synthesis of (-)-hemiasterlin (2), a structurally novel, naturally occurring tripeptide that exhibits potent cytotoxic and antimitotic activity against human breast cancer MCF7 cells, is described. Copyright (C) 1996 Elsevier Science Ltd},
	keywords = {ALPHA-AMINO-ACIDS, ASYMMETRIC-SYNTHESIS, AZIDATION, PEPTIDES},
	isbn = {0040-4039},
	url = {<Go to ISI>://A1997WC80700005},
	author = {Andersen, R. J. and Coleman, J. E. and Piers, E. and Wallace, D. J.}
}
@article {3634,
	title = {Hemiasterlin methyl ester},
	journal = {Acta Crystallographica Section C-Crystal Structure Communications},
	volume = {52},
	year = {1996},
	note = {ISI Document Delivery No.: UX298Times Cited: 13Cited Reference Count: 11Part 6},
	month = {Jun},
	pages = {1525-1527},
	type = {Article},
	abstract = {The structure of the tripeptide hemiasterlin methyl ester, C31H48N4O4, has been determined by X-ray analysis, The absolute configuration is based on the chiralities determined by other methods for two of the three chiral centers, Weak hydrogen bonding influences the solid-state conformation.},
	keywords = {PEPTIDES},
	isbn = {0108-2701},
	url = {<Go to ISI>://A1996UX29800079},
	author = {Coleman, J. E. and Patrick, B. O. and Andersen, R. J. and Rettig, S. J.}
}
