Open Access. Powered by Scholars. Published by Universities.®
- Discipline
-
- Organic Chemistry (13)
- Physical Chemistry (11)
- Polymer Chemistry (10)
- Life Sciences (7)
- Biochemistry, Biophysics, and Structural Biology (6)
-
- Biochemistry (4)
- Materials Chemistry (4)
- Engineering (3)
- Materials Science and Engineering (3)
- Analytical Chemistry (2)
- Medicinal-Pharmaceutical Chemistry (2)
- Medicine and Health Sciences (2)
- Other Chemistry (2)
- Biodiversity (1)
- Biophysics (1)
- Chemical Engineering (1)
- Chemicals and Drugs (1)
- Ecology and Evolutionary Biology (1)
- Lipids (1)
- Medical Immunology (1)
- Medical Sciences (1)
- Molecular and Cellular Neuroscience (1)
- Neuroscience and Neurobiology (1)
- Polymer and Organic Materials (1)
- Radiochemistry (1)
- Institution
- Keyword
-
- Molecular Dynamics Simulation (19)
- Electrospray Ionization (12)
- Mass (12)
- Spectrometry (12)
- Spectrometry, Mass, Electrospray Ionization (12)
-
- Protein Conformation (11)
- Animals (10)
- Humans (10)
- Gases (9)
- Molecular Structure (9)
- Catalysis (7)
- Cyclization (7)
- Ions (7)
- Myoglobin (7)
- Stereoisomerism (7)
- Cobalt (6)
- Corrosion (6)
- Gold (6)
- Models (6)
- Oxidation-Reduction (6)
- Raman (6)
- Spectrum Analysis (6)
- Spectrum Analysis, Raman (6)
- Chromium (5)
- Ion Mobility Spectrometry (5)
- Mass spectrometry (5)
- Metal Nanoparticles (5)
- Metal release (5)
- Models, Molecular (5)
- Molecular (5)
Articles 61 - 90 of 333
Full-Text Articles in Chemistry
Welding Fume Nanoparticles From Solid And Flux-Cored Wires: Solubility, Toxicity, And Role Of Fluorides, Yolanda S. Hedberg, Z. Wei, S. Mccarrick, V. Romanovski, J. Theodore, E. M. Westin, R. Wagner, K.-A. Persson, H. L. Karlsson, I. Odnevall Wallinder
Welding Fume Nanoparticles From Solid And Flux-Cored Wires: Solubility, Toxicity, And Role Of Fluorides, Yolanda S. Hedberg, Z. Wei, S. Mccarrick, V. Romanovski, J. Theodore, E. M. Westin, R. Wagner, K.-A. Persson, H. L. Karlsson, I. Odnevall Wallinder
Chemistry Publications
Welding fume particles are hazardous. Their toxicity likely depends on their composition and reactivity. This study aimed at exploring the role of sodium or other fluorides (NaF), which are intentionally added to flux-cored wire electrodes for stainless steel welding, on the solubility (in phosphate buffered saline) and toxicity of the generated welding fume particles. A multi-analytical particle characterization approach along with in-vitro cell assays was undertaken. The release of Cr(VI) and Mn from the particles was tested as a function of fluoride solution concentration. The welding fume particles containing NaF released significantly higher amounts of Cr(VI) compared with solid wire …
Sulfolane-Induced Supercharging Of Electrosprayed Salt Clusters: An Experimental/Computational Perspective., Leanne M Martin, Lars Konermann
Sulfolane-Induced Supercharging Of Electrosprayed Salt Clusters: An Experimental/Computational Perspective., Leanne M Martin, Lars Konermann
Chemistry Publications
It is well-known that supercharging agents (SCAs) such as sulfolane enhance the electrospray ionization (ESI) charge states of proteins, although the mechanistic origins of this effect remain contentious. Only very few studies have explored SCA effects on analytes other than proteins or peptides. This work examines how sulfolane affects electrosprayed NaI salt clusters. Such alkali metal halide clusters have played a key role for earlier ESI mechanistic studies, making them interesting targets for supercharging investigations. ESI of aqueous NaI solutions predominantly generated singly charged [NanI(n-1)]+ clusters. The addition of sulfolane resulted in abundant …
Experimental And Computational Observations Of Immunogenic Cobalt Porphyrin Lipid Bilayers: Nanodomain-Enhanced Antigen Association., Jasmin Federizon, Conrard Giresse Tetsassi Feugmo, Wei-Chiao Huang, Xuedan He, Kazutoyo Miura, Aida Razi, Joaquin Ortega, Mikko Karttunen, Jonathan F Lovell
Experimental And Computational Observations Of Immunogenic Cobalt Porphyrin Lipid Bilayers: Nanodomain-Enhanced Antigen Association., Jasmin Federizon, Conrard Giresse Tetsassi Feugmo, Wei-Chiao Huang, Xuedan He, Kazutoyo Miura, Aida Razi, Joaquin Ortega, Mikko Karttunen, Jonathan F Lovell
Chemistry Publications
Cobalt porphyrin phospholipid (CoPoP) can incorporate within bilayers to enable non-covalent surface-display of antigens on liposomes by mixing with proteins bearing a polyhistidine tag (his-tag); however, the mechanisms for how this occurs are poorly understood. These were investigated using the his-tagged model antigen Pfs25, a protein antigen candidate for malaria transmission-blocking vaccines. Pfs25 was found to associate with the small molecule aquocobalamin, a form of vitamin B12 and a cobalt-containing corrin macrocycle, but without particle formation, enabling comparative assessment. Relative to CoPoP liposomes, binding and serum stability studies indicated a weaker association of Pfs25 to aquocobalamin or cobalt nitrilotriacetic acid …
Single-Beam Inscription Of Plasmon-Induced Surface Gratings, Denis Ab Therien, Nina M. Culum, Danielle M. Mcrae, Leila Mazaheri, Francois Lagugne-Labarthet
Single-Beam Inscription Of Plasmon-Induced Surface Gratings, Denis Ab Therien, Nina M. Culum, Danielle M. Mcrae, Leila Mazaheri, Francois Lagugne-Labarthet
Chemistry Publications
The formation of gratings on gold nanoprisms arrays by plasmon-mediated reduction of a diazonium salt is investigated. Nanosphere lithography (NSL) is used to produce large surfaces of gold nanoprisms that are effective at reducing diazonium salts by producing hot electrons through excitation of localized surface plasmon resonances (LSPRs). Using single beam irradiation, we report here on the formation of periodic structures formed from the diazonium salts and that follow the NSL structures. On plasmonically active nanoprism substrates, the electric field enhancement promotes chemical reduction and hence modifies the grafting direction and grating properties of the ripples. The nanoprisms act as …
Interrogating The Quaternary Structure Of Noncanonical Hemoglobin Complexes By Electrospray Mass Spectrometry And Collision-Induced Dissociation., Alexander I M Sever, Victor Yin, Lars Konermann
Interrogating The Quaternary Structure Of Noncanonical Hemoglobin Complexes By Electrospray Mass Spectrometry And Collision-Induced Dissociation., Alexander I M Sever, Victor Yin, Lars Konermann
Chemistry Publications
Various activation methods are available for the fragmentation of gaseous protein complexes produced by electrospray ionization (ESI). Such experiments can potentially yield insights into quaternary structure. Collision-induced dissociation (CID) is the most widely used fragmentation technique. Unfortunately, CID of protein complexes is dominated by the ejection of highly charged monomers, a process that does not yield any structural insights. Using hemoglobin (Hb) as a model system, this work examines under what conditions CID generates structurally informative subcomplexes. Native ESI mainly produced tetrameric Hb ions. In addition, "noncanonical" hexameric and octameric complexes were observed. CID of all these species [(αβ)2 …
Probing The Effects Of Heterogeneous Oxidative Modifications On The Stability Of Cytochrome, Victor Yin, Lars Konermann
Probing The Effects Of Heterogeneous Oxidative Modifications On The Stability Of Cytochrome, Victor Yin, Lars Konermann
Chemistry Publications
Covalent modifications by reactive oxygen species can modulate the function and stability of proteins. Thermal unfolding experiments in solution are a standard tool for probing oxidation-induced stability changes. Complementary to such solution investigations, the stability of electrosprayed protein ions can be assessed in the gas phase by collision-induced unfolding (CIU) and ion-mobility spectrometry. A question that remains to be explored is whether oxidation-induced stability alterations in solution are mirrored by the CIU behavior of gaseous protein ions. Here, we address this question using chloramine-T-oxidized cytochrome c (CT-cyt c) as a model system. CT-cyt c comprises various proteoforms that have …
A Strongly Lewis-Acidic And Fluorescent Borenium Cation Supported By A Tridentate Formazanate Ligand, Benjamin D. Katzman, Ryan R. Maar, Daniela Cappello, Madeleine O. Sattler, Paul D. Boyle, Viktor N. Staroverov, Joe B. Gilroy
A Strongly Lewis-Acidic And Fluorescent Borenium Cation Supported By A Tridentate Formazanate Ligand, Benjamin D. Katzman, Ryan R. Maar, Daniela Cappello, Madeleine O. Sattler, Paul D. Boyle, Viktor N. Staroverov, Joe B. Gilroy
Chemistry Publications
Lewis acids are highly sought after for their applications in sensing, small-molecule activation, and catalysis. When combined with π-conjugated molecular frameworks, Lewis acids with unique optoelectronic properties can be realized. Here, we use a tridentate formazanate ligand to create a planar, redox-active, fluorescent, and strongly Lewis-acidic borenium cation. We also demonstrate that this compound can act as a colourimetric probe for reactivity.
Reversible Electrowetting Transitions On Superhydrophobic Surfaces, D. Vanzo, A. Luzar, D. Bratko
Reversible Electrowetting Transitions On Superhydrophobic Surfaces, D. Vanzo, A. Luzar, D. Bratko
Chemistry Publications
Electric field applied across the interface has been shown to enable transitions from Cassie to Wenzel state on superhydrophobic surfaces with miniature corrugations. Molecular Dynamics (MD) simulations manifest the possibility of reversible cycling between the two states when narrow surface wells support spontaneous expulsion of water in the absence of the field. With approximately 1 nm sized wells between the surface asperities, response times to changes of electric field are of O(0.1) ns, allowing up to GHz frequency of the cycle. Because of orientation preferences of interfacial water in contact with the solid, the phenomenon depends on the polarity of …
Strained Alkyne Polymers Capable Of Spaac Via Ring-Opening Metathesis Polymerization, Rajeshwar Vasdev, Wilson Luo, Kyle Classen, Michael Anghel, Samantha Novoa, Mark S. Workentin, Joe B. Gilroy
Strained Alkyne Polymers Capable Of Spaac Via Ring-Opening Metathesis Polymerization, Rajeshwar Vasdev, Wilson Luo, Kyle Classen, Michael Anghel, Samantha Novoa, Mark S. Workentin, Joe B. Gilroy
Chemistry Publications
The incorporation of strained alkynes into polymers is generally achieved by employing step-growth polymerization methods or post-polymerization reactions. Here, we demonstrate that cyclopropenone-masked strained alkynes are tolerant to chain-growth ring-opening metathesis polymerization, and that, upon post-polymerization photochemical demasking with loss of CO, the strained alkyne group appended to each repeating unit can be used to prepare functional (e.g., fluorescent or redox-active) polymers from a common polymer backbone. We support our claims about polymer transformations throughout the manuscript through the inclusion of a complete set of model reactions and characterization data for analogous molecular species. The findings of this …
Metal Bioaccessibility In Synthetic Bodyfluids–A Way To Considerpositive And Negative Alloying Effects In Hazard Assessments, Yolanda S. Hedberg, Xuying Wang, James J. Noël, Inger Odnevall Wallinder
Metal Bioaccessibility In Synthetic Bodyfluids–A Way To Considerpositive And Negative Alloying Effects In Hazard Assessments, Yolanda S. Hedberg, Xuying Wang, James J. Noël, Inger Odnevall Wallinder
Chemistry Publications
Hazard classification of metal alloys is today generally based on their bulk content, an approach that seldom reflects the extent of metal release for a given environment. Such information can instead be achieved via bioelution testing under simulated physiological conditions. The use of bioelution data instead of bulk contents would hence refine the current hazard classification of alloys and enable grouping. Bioelution data have been generated for nickel (Ni) and cobalt (Co) released from several stainless steel grades, one low-alloyed steel, and Ni and Co metals in synthetic sweat, saliva and gastric fluid, for exposure periods from 2 to 168 …
Band-Gap Tuning In Acceptor-Donor-Acceptor Boron Difluoride Formazanates, Francis L. Buguis, Michael Anghel, Joe B. Gilroy, Jasveer S. Dhindsa
Band-Gap Tuning In Acceptor-Donor-Acceptor Boron Difluoride Formazanates, Francis L. Buguis, Michael Anghel, Joe B. Gilroy, Jasveer S. Dhindsa
Chemistry Publications
π-Conjugated molecules with acceptor-donor-acceptor (A-D-A) electronic structures are an important class of materials due to their tunable optoelectronic properties and applications in, for example, organic light-emitting diodes, nonlinear optical devices, and organic solar cells. The frontier molecular orbital energies, and thus band gaps, of these materials can be tuned by varying the donor and acceptor traits and π-electron counts of the structural components. Herein, we report the synthesis and characterization of a series of A-D-A compounds consisting of BF2 formazanates as electron acceptors bridged by a variety of π-conjugated donors. The results, which are supported by DFT calculations, demonstrate …
New Weldable 316l Stainless Flux-Cored Wires With Reduced Cr(Vi) Fume Emissions Part 2 – Round Robin Creating Fume Emission Data Sheets, Yolanda Hedberg
New Weldable 316l Stainless Flux-Cored Wires With Reduced Cr(Vi) Fume Emissions Part 2 – Round Robin Creating Fume Emission Data Sheets, Yolanda Hedberg
Chemistry Publications
Welding fumes have been found to be carcinogenic and stainless steel welders may be at higher risk due to increased formation of hexavalent chromium (Cr(VI)). The slag-shielded methods, identified to generate most airborne particles and Cr(VI), would potentially be most harmful. With ever-stricter limits set to protect workers, measures to minimize human exposure become crucial. Austenitic stainless steel flux-cored wires of 316L type have been developed with the aim to reduce the toxicity of the welding fume without compromised usability. Collected particles were compared with fumes formed using solid, metal-cored and standard flux-cored wires. In Part 1, the new wires …
New Weldable 316l Stainless Flux-Cored Wires With Reduced Cr(Vi) Fume Emissions Part 1 – Health Aspects Of Particle Composition And Release Of Metals, Yolanda Hedberg
New Weldable 316l Stainless Flux-Cored Wires With Reduced Cr(Vi) Fume Emissions Part 1 – Health Aspects Of Particle Composition And Release Of Metals, Yolanda Hedberg
Chemistry Publications
Welding fumes have been found to be carcinogenic and stainless steel welders may be at higher risk due to increased formation of hexavalent chromium (Cr(VI)). The slag-shielded methods, identified to generate most airborne particles and Cr(VI), would potentially be most harmful. With ever-stricter limits set to protect workers, measures to minimize human exposure become crucial. Austenitic stainless steel flux-cored wires of 316L type have been developed with the aim to reduce the toxicity of the welding fume without compromised usability. Collected particles were compared with fumes formed using solid, metal-cored and standard flux-cored wires. The size, morphology and composition were …
Corrosion Failure Of Titanium Tubes Of A Heat Exchanger For The Heating Of Dissolving Lye, Valentin Romanovski, Yolanda S. Hedberg, Andrei Paspelau, Vitali Frantskevich, James J. Noël, Elena Romanovskaia
Corrosion Failure Of Titanium Tubes Of A Heat Exchanger For The Heating Of Dissolving Lye, Valentin Romanovski, Yolanda S. Hedberg, Andrei Paspelau, Vitali Frantskevich, James J. Noël, Elena Romanovskaia
Chemistry Publications
Corrosion of titanium heat exchangers in the processing of sylvinite ore is undesirable from economic, safety, and process sustainability perspectives. Triggered by an industrial case, we investigated the extent of corrosion during simulated contact with sylvinite ore (in dissolving lye) in relevant conditions. Detailed characterization of the failed tubes and corrosion products was carried out to understand the mechanism of failure. Corrosion of titanium (Grade 2) tubes was investigated at room temperature, 60, 70, 80, and 90 °C. After electrochemical and surface morphology analysis, we found that pitting corrosion of the titanium tube material sharply increased above 80 °C in …
A Boron Difluoride Hydrazone (Bodihy) Polymer Exhibits Aggregation-Induced Emission, Alexander E. R. Watson, Joe Gilroy, Daniela Cappello
A Boron Difluoride Hydrazone (Bodihy) Polymer Exhibits Aggregation-Induced Emission, Alexander E. R. Watson, Joe Gilroy, Daniela Cappello
Chemistry Publications
Polymers that exhibit aggregation-induced emission (AIE) find use, for example, as cell-imaging agents and as fluorometric sensors due to their unique optical properties. However, the structural diversity of AIE-active polymers has not necessarily advanced at the same rate as their applications. In this work, ring-opening metathesis polymerization is used to synthesize the first example of a polymer (Mn = 61,600 g mol‒1, Đ = 1.32) containing boron difluoride hydrazone (BODIHY) heterocycles in its repeating unit. The BODIHY monomer and polymer described absorb and emit in the visible region in solution (λabs = 428 and 429 nm, …
Unspecified Verticality Of Franck-Condon Transitions, Absorption And Emission Spectra Of Cyanine Dyes, And A Classically Inspired Approximation, Joseph D. Alia, Joseph A. Flack
Unspecified Verticality Of Franck-Condon Transitions, Absorption And Emission Spectra Of Cyanine Dyes, And A Classically Inspired Approximation, Joseph D. Alia, Joseph A. Flack
Chemistry Publications
The computed vertical energy, Ev,a/f, from the equilibrium geometry of the initial electronic state is frequently considered as representative of the experimental excitation/emission energy, Eabs/fl = hc/λmax. Application of the quantum mechanical version of the Franck–Condon principle does not involve precise specification of nuclear positions before, after, or during an electronic transition. Moreover, the duration of an electronic transition is not experimentally accessible in spectra with resolved vibrational structure. It is shown that computed vibronic spectra based on TDDFT methods and application of quantum mechanical FC analysis predict Eabs = hc/λmax …
Cationic Boron Formazanate Dyes, Benjamin D. Katzman, Paul D. Boyle, Viktor N. Staroverov, Joe Gilroy, Ryan R. Maar
Cationic Boron Formazanate Dyes, Benjamin D. Katzman, Paul D. Boyle, Viktor N. Staroverov, Joe Gilroy, Ryan R. Maar
Chemistry Publications
Incorporation of cationic boron atoms into molecular frameworks is an established strategy for creating chemical species with unusual bonding and reactivity but is rarely thought of as a way of enhancing molecular optoelectronic properties. Using boron formazanate dyes as examples, we demonstrate that the wavelengths, intensities, and type of the first electronic transitions in BN heterocycles can be modulated by varying the charge, coordination number, and supporting ligands at the cationic boron atom. UV‐vis absorption spectroscopy measurements and density‐functional (DFT) calculations show that these modulations are caused by changes in the geometry and extent of π‐conjugation of the boron formazanate …
Near-Infrared Boron Difluoride Formazanate Dyes, Francis L. Buguis, Ryan R. Maar, Viktor N. Staroverov, Joe Gilroy
Near-Infrared Boron Difluoride Formazanate Dyes, Francis L. Buguis, Ryan R. Maar, Viktor N. Staroverov, Joe Gilroy
Chemistry Publications
Near-infrared (NIR) dyes are sought after for their utility in light harvesting, bioimaging, and light-mediated therapies. Since long-wavelength photoluminescence typically involves extensive p-conjugated systems of double bonds and aromatic rings, it is often assumed that NIR dyes have to be large molecules that require complex syntheses. We challenge this assumption by demonstrating that facile incorporation of tertiary amine groups into readily available 3-cyanoformazans affords efficient production of relatively simple NIR-active BF2 formazanate dyes (λabs = 691−760 nm, λPL = 834−904 nm in toluene). Cyclic voltammetry experiments on these compounds reveal multiple reversible redox waves linked to the …
Delineating Heme-Mediated Versus Direct Protein Oxidation In Peroxidase-Activated Cytochrome, Victor Yin, Derek Holzscherer, Lars Konermann
Delineating Heme-Mediated Versus Direct Protein Oxidation In Peroxidase-Activated Cytochrome, Victor Yin, Derek Holzscherer, Lars Konermann
Chemistry Publications
Oxidation of key residues in cytochrome c (cyt c) by chloramine T (CT) converts the protein from an electron transporter to a peroxidase. This peroxidase-activated state represents an important model system for exploring the early steps of apoptosis. CT-induced transformations include oxidation of the distal heme ligand Met80 (MetO, +16 Da) and carbonylation (LysCHO, -1 Da) in the range of Lys53/55/72/73. Remarkably, the 15 remaining Lys residues in cyt c are not susceptible to carbonylation. The cause of this unusual selectivity is unknown. Here we applied top-down mass spectrometry (MS) to examine whether CT-induced oxidation is catalyzed by heme. …
Transesterification Of Poly(Ethyl Glyoxylate): A Route To Structurally Diverse Polyglyoxylates, Rebecca E. Yardley, Amir Rabiee Kenaree, Xiaoli Liang, Elizabeth R. Gillies
Transesterification Of Poly(Ethyl Glyoxylate): A Route To Structurally Diverse Polyglyoxylates, Rebecca E. Yardley, Amir Rabiee Kenaree, Xiaoli Liang, Elizabeth R. Gillies
Chemistry Publications
Polyglyoxylates are a class of self-immolative polymers that depolymerize in solution and the solid state. The glyoxylic acid degradation product is a metabolite in the glyoxylate cycle and can also be processed in the liver in humans, making polyglyoxylates attractive for applications in the environment and in medicine. Although expanding the scope of available polyglyoxylates would enable new properties and applications, highly pure glyoxylate monomers are required for polymerization, and this level of purity is difficult to achieve for many potential monomers. To address this challenge, we report here the 1,5,7-triazabicyclo[4.4.0]dec-5-ene (TBD)-catalyzed post-polymerization transesterification of poly(ethyl glyoxylate) (PEtG) as a …
Deciphering Tip-Enhanced Raman Imaging Of Carbon Nanotubes With Deep Learning Neural Networks., Usant Kajendirarajah, María Olivia Avilés, François Lagugné-Labarthet
Deciphering Tip-Enhanced Raman Imaging Of Carbon Nanotubes With Deep Learning Neural Networks., Usant Kajendirarajah, María Olivia Avilés, François Lagugné-Labarthet
Chemistry Publications
Recent release of open-source machine learning libraries presents opportunities to unify machine learning with nanoscale research, thus improving effectiveness of research methods and characterization protocols. This paper outlines and demonstrates the effectiveness of such a synergy with artificial neural networks to provide for an accelerated and enhanced characterization of individual carbon nanotubes deposited over a surface. Our algorithms provide a rapid diagnosis and analysis of tip-enhanced Raman spectroscopy mappings and the results show an improved spectral assignment of spectral features and spatial contrast of the collected images. Using several examples, we demonstrate the robustness and versatility of our deep learning …
Thermoresponsive Self-Immolative Polyglyoxylamides., Amir Rabiee Kenaree, Quinton E. A. Sirianni, Kyle Classen, Elizabeth R. Gillies
Thermoresponsive Self-Immolative Polyglyoxylamides., Amir Rabiee Kenaree, Quinton E. A. Sirianni, Kyle Classen, Elizabeth R. Gillies
Chemistry Publications
Thermoresponsive polymers with lower critical solution temperatures (LCSTs) are of significant interest for a wide range of applications from sensors to drug delivery vehicles. However, the most widely investigated LCST polymers have nondegradable backbones, limiting their applications
Formation Of Gaseous Proteins Via The Ion Evaporation Model (Iem) In Electrospray Mass Spectrometry., Elnaz Aliyari, Lars Konermann
Formation Of Gaseous Proteins Via The Ion Evaporation Model (Iem) In Electrospray Mass Spectrometry., Elnaz Aliyari, Lars Konermann
Chemistry Publications
The mechanisms whereby protein ions are released into the gas phase from charged droplets during electrospray ionization (ESI) continue to be controversial. Several pathways have been proposed. For native ESI the charged residue model (CRM) is favored; it entails the liberation of proteins via solvent evaporation to dryness. Unfolded proteins likely follow the chain ejection model (CEM), which involves the gradual expulsion of stretched-out chains from the droplet. According to the ion evaporation model (IEM) ions undergo electrostatically driven desorption from the droplet surface. The IEM is well supported for small precharged species such as Na+. However, it …
Analysis Of Temperature-Dependent H/D Exchange Mass Spectrometry Experiments., Nastaran N Tajoddin, Lars Konermann
Analysis Of Temperature-Dependent H/D Exchange Mass Spectrometry Experiments., Nastaran N Tajoddin, Lars Konermann
Chemistry Publications
H/D exchange (HDX) mass spectrometry (MS) is a widely used technique for interrogating protein structure and dynamics. Backbone HDX is mediated by opening/closing (unfolding/refolding) fluctuations. In traditional HDX-MS, proteins are incubated in D2O as a function of time at constant temperature (T). There is an urgent need to complement this traditional approach with experiments that probe proteins in a T-dependent fashion, e.g., for assessing the stability of therapeutic antibodies. A key problem with such studies is the absence of strategies for interpreting HDX-MS data in the context of T-dependent protein dynamics. Specifically, it has …
Phosphonium Versus Ammonium Compact Polyelectrolyte Complex Networks With Alginate-Comparing Their Properties And Cargo Encapsulation., Tristan D. Harrison, Alexandre J. Salmon, John R. De Bruyn, Paul J. Ragogna, Elizabeth R. Gillies
Phosphonium Versus Ammonium Compact Polyelectrolyte Complex Networks With Alginate-Comparing Their Properties And Cargo Encapsulation., Tristan D. Harrison, Alexandre J. Salmon, John R. De Bruyn, Paul J. Ragogna, Elizabeth R. Gillies
Chemistry Publications
Phosphonium and ammonium polymers can be combined with polyanions to form polyelectrolyte complex (PEC) networks, with potential application in self-healing materials and drug delivery vehicles. While various structures and compositions have been explored, to the best of our knowledge, analogous ammonium and phosphonium networks have not been directly compared to evaluate the effects of phosphorus versus nitrogen cations on the network properties. In this study, we prepared PECs from sodium alginate and poly[triethyl(4-vinylbenzyl)phosphonium chloride], poly[triethyl(4-vinylbenzyl)ammonium chloride], poly[tri(
Benzosiloles With Crystallization-Induced Emission Enhancement Of Electrochemiluminescence: Synthesis, Electrochemistry, And Crystallography, Liuqing Yang, Donghyun Koo, Jackie Wu, Jonathan M. Wong, Tyler Day, Ruizhong Zhang, Harshana Kolongoda, Kehan Liu, Jian Wang, Zhifeng Ding, Brian Pagenkopf
Benzosiloles With Crystallization-Induced Emission Enhancement Of Electrochemiluminescence: Synthesis, Electrochemistry, And Crystallography, Liuqing Yang, Donghyun Koo, Jackie Wu, Jonathan M. Wong, Tyler Day, Ruizhong Zhang, Harshana Kolongoda, Kehan Liu, Jian Wang, Zhifeng Ding, Brian Pagenkopf
Chemistry Publications
Crystallization-induced emission enhancement (CIEE) was demonstrated for the first time for electrochemilunimescence (ECL) with two new benzosiloles. Compared with their solution, the films of the two benzosiloles gave CIEE of 24 times and 16 times. The mechanism of the CIEE-ECL was examined by spooling ECL spectroscopy, X-ray crystal structure analysis, photoluminescence, and DFT calculation. This CIEE-ECL system is a complement to the well-established aggregation-induced emission enhancement (AIEE) systems. Unique intermolecular interactions are noted in the crystalline chromophore. The first heterogeneous ECL system is established for organic compounds with highly hydrophobic properties.
Gas Phase Protein Folding Triggered By Proton Stripping Generates Inside-Out Structures: A Molecular Dynamics Simulation Study., Alexander I M Sever, Lars Konermann
Gas Phase Protein Folding Triggered By Proton Stripping Generates Inside-Out Structures: A Molecular Dynamics Simulation Study., Alexander I M Sever, Lars Konermann
Chemistry Publications
The properties of electrosprayed protein ions continue to be enigmatic, owing to the absence of high-resolution structure determination methods in the gas phase. There is considerable evidence that under properly optimized conditions these ions preserve solution-like conformations and interactions. However, it is unlikely that these solution-like conformers represent the "intrinsic" structural preferences of gaseous proteins. In an effort to uncover what such intrinsically preferred conformers might look like, we performed molecular dynamics (MD) simulations of gaseous ubiquitin. Our work was inspired by recent gas phase experiments, where highly extended 13+ ubiquitin ions were transformed to compact 3+ species by proton …
Computation Of Atmospheric Concentrations Of Molecular Clusters From Ab Initio Thermochemistry, Tuguldur T. Odbadrakh, Ariel G. Gale, Benjamin T. Ball, Berhane Temelso, George C. Shields
Computation Of Atmospheric Concentrations Of Molecular Clusters From Ab Initio Thermochemistry, Tuguldur T. Odbadrakh, Ariel G. Gale, Benjamin T. Ball, Berhane Temelso, George C. Shields
Chemistry Publications
The computational study of the formation and growth of atmospheric aerosols requires an accurate Gibbs free energy surface, which can be obtained from gas phase electronic structure and vibrational frequency calculations. These quantities are valid for those atmospheric clusters whose geometries correspond to a minimum on their potential energy surfaces. The Gibbs free energy of the minimum energy structure can be used to predict atmospheric concentrations of the cluster under a variety of conditions such as temperature and pressure. We present a computationally inexpensive procedure built on a genetic algorithm-based configurational sampling followed by a series of increasingly accurate screening …
Hierarchical Plasmon Resonances In Fractal Structures, Isobel C. Bicket, Edson P. Bellido, Danielle M. Mcrae, Francois Lagugne-Labarthet, Gianluigi A. Botton
Hierarchical Plasmon Resonances In Fractal Structures, Isobel C. Bicket, Edson P. Bellido, Danielle M. Mcrae, Francois Lagugne-Labarthet, Gianluigi A. Botton
Chemistry Publications
An equilateral triangular prism is used as the fundamental building block to con- struct additive Sierpinski fractals, enabling new surface plasmon resonances (SPR) in the first three generations of Sierpinski triangles, as well as topological intermediaries between generations. The modes are characterized using electron energy loss spectroscopy accompanied by eigenmode calculations and optical finite-difference time domain simulations. The complex fractal geometries present a predictable hierarchy of new resonances, each arising from the previous generational building blocks used to construct the fractal. Intermediate structures break the polarization degeneracy of the equilateral fractals while maintaining a rich multiband spectral response. Engineering defects …
Quantum Chemical Lipophilicities Of Antimalarial Drugs In Relation To Terminal Half-Life, Joseph D. Alia, Sheila Karl, Tyler D. Kelly
Quantum Chemical Lipophilicities Of Antimalarial Drugs In Relation To Terminal Half-Life, Joseph D. Alia, Sheila Karl, Tyler D. Kelly
Chemistry Publications
According to the WHO, artemisinin-based combination therapies (ACTs) have been integral to the recent reduction in deaths due to Plasmodium falciparum malaria. ACT-resistant strains are an emerging problem and have evolved altered developmental stages, reducing exposure of the most susceptible stages to artemisinin drugs in popular ACTs. Lipophilicity, log Kow, is a guide in understanding and predicting pharmacokinetic properties such as terminal half-life which alters drug exposure. Consistent log Kow values are not necessarily available for artemisinin derivatives designed to extend terminal half-life, increase bioavailability, and reduce neurotoxicity. For other drugs used in ACTs, an assortment of …