A heteroleptic [Pd

Electrospray ionization (ESI) mass spectrometry (MS) is a crucial method for rapidly determining the interactions between small molecules and proteins with ultrahigh sensitivity. However, nonvolatile salts that are often necessary to stabilize native structures of protein-ligand complexes can readily adduct protein ions, broaden spectral peaks, lower signal-to-noise ratios in MS. ESI emitters narrow tip diameters (∼250 nm) were used significantly reduce extent adduction salt more accurately...

A photoswitchable ligand based on azobenzene is self-assembled with palladium(II) ions to form a [Pd

Cytochrome P450 heme-thiolate monooxygenases are exceptionally versatile enzymes which insert an oxygen atom into the unreactive C–H bonds of organic molecules. They source O2 from atmosphere and usually derive electrons nicotinamide cofactors via electron transfer proteins. The requirement for expensive adenine dinucleotide (phosphate) cofactor redox protein partners can be bypassed by driving catalysis using hydrogen peroxide (H2O2). We demonstrate that mutation a highly conserved...

A photoswitchable ligand and palladium(II) ions form a dynamic mixture of self-assembled metallosupramolecular structures. The photoswitching is an ortho-fluoroazobenzene with appended pyridyl groups. Combining the E-isomer salts affords double-walled triangle composition [Pd3 L6 ]6+ distorted tetrahedron [Pd4 L8 ]8+ (1 : 2 ratio at 298 K). Irradiation 410 nm light generates photostationary state approximately 80 % results in selective disassembly tetrahedron, more thermodynamically stable...

In solution, half-cell potentials are measured relative to those of other half cells, thereby establishing a ladder thermochemical values that referenced the standard hydrogen electrode (SHE), which is arbitrarily assigned value exactly 0 V. Although there has been considerable interest in, and efforts toward, an absolute electrochemical potential in no general consensus regarding best approach obtain this value. Here, ion-electron recombination energies resulting from electron capture by...

The extent of internal energy deposition into ions upon storage, radial ejection, and detection using a linear quadrupole ion trap mass spectrometer is investigated as function size (m/z 59 to 810) seven ion-molecule thermometer reactions that have well characterized reaction entropies enthalpies. average effective temperatures the reactants products reactions, which were obtained from equilibrium measurements, range 295 350 K do not depend significantly on number trapped ions, m/z value, q...

CH vs OH CO bond activation? The non-heme complex [(bpg)FeIVO]+ activates the αCH of primary alcohols in vacuum through H abstraction by FeO group rate-determining step. Although this effect counteracts any enhancement reactivity that results from increasing formal oxidation state Fe, it increases reaction selectivity. Detailed facts importance to specialist readers are published as ”Supporting Information”. Such documents peer-reviewed, but not copy-edited or typeset. They made...

Electrospray ionization (ESI) can be used to form multiply charged ions, which is beneficial for obtaining accurate molecular weight values and sequence information proteins in many types of mass spectrometry (MS) measurements. The effects surface tension, dipole moment, dielectric constant (properties that have been implicated the enhancement protein charging ESI) 14 solution additives on charge-state distributions are formed ESI three (ubiquitin, cytochrome c, carbonic anhydrase II) were...

Substitution-inert, redox- and photo-active ruthenium(<sc>ii</sc>) complexes based on 2,2′,6′,2′′-terpyridine ligands were self-assembled into discrete supramolecular cages <italic>via</italic> coordination to palladium(<sc>ii</sc>) centres characterised by NMR, ESI-MS X-ray crystallography.

We report the development of metal–organic framework (MOF)-based probes for direct and rapid detection quantification perfluorooctanoic acid (PFOA) by mass spectrometry. Four water-resistant MOFs—ZIF-8, UiO-66, MIL88-A, Tb2(BDC)3—were coated on poly(dopamine) precoated stainless steel needles used to rapidly preconcentrate PFOA from water analysis nanoelectrospray ionization The analytical performance each MOF detecting was correlated with both calculated binding energy relative change in...

The structural diversity of natural products offers unique opportunities for drug discovery, but challenges associated with their isolation and screening can hinder the identification drug-like molecules from complex product extracts. Here we introduce a mass spectrometry-based approach that integrates untargeted metabolomics multistage, high-resolution native spectrometry to rapidly identify bind therapeutically relevant protein targets. By directly crude extracts containing thousands small...

The use of machine learning (ML) with metabolomics provides opportunities for the early diagnosis disease. However, accuracy ML and extent information obtained from can be limited owing to challenges associated interpreting disease prediction models analyzing many chemical features abundances that are correlated "noisy". Here, we report an interpretable neural network (NN) framework accurately predict identify significant biomarkers using whole data sets without a priori feature selection....

In solution, half-cell potentials are measured relative to other half-cells resulting in a ladder of thermodynamic values that is anchored the standard hydrogen electrode (SHE), which assigned an arbitrary value exactly 0 V. A new method for measuring absolute SHE potential introduced reduction energies Eu(H2O)n3+, from n = 55 140, extrapolated as function geometric dependence cluster energy infinite size. These measurements make it possible directly relate these gaseous nanodrops containing...

High-performance solutions for supercharging proteins in electrospray ionization were optimized and the origin of strong dependence on acid strength was investigated.

Insecticide resistance is one of the most prevalent examples anthropogenic genetic change, yet our understanding metabolic-based remains limited by analytical challenges associated with rapidly tracking in vivo metabolites insecticides at nonlethal doses. Here, using twin ion mass spectrometry analysis extracts whole Drosophila larvae and excreta, we show that (i) eight neonicotinoid insecticide, imidacloprid, can be detected when formed susceptible larval genotypes (ii) specific...

Supercharging electrospray ionization can be a powerful tool for increasing charge states in mass spectra and generating unfolded ion structures, yet key details of its mechanism remain unclear. The structures highly extended protein ions the supercharging were investigated using mobility-mass spectrometry. Head-to-tail-linked polyubiquitins (Ubq1-11) used to determine size state scaling laws formed by while eliminating amino acid composition as potential confounding factor. Collisional...

Perfluoroalkyl substances (PFASs) persist and are ubiquitous in the environment. The origins of PFAS toxicity how they specifically affect functions proteins remain unclear. Herein, we report that PFASs can strongly inhibit activity human carbonic anhydrases (hCAs), which enzymes catalyze hydration CO2, abundant blood organs mammals, involved pH regulation, ion homeostasis, biosynthesis. interactions between hCAs were investigated using stopped-flow kinetic enzyme-inhibition measurements,...