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A novel analytical workflow for suspect screening of organic acidic contaminants in drinking water is presented, featuring selective extraction by silica-based strong anion-exchange solid-phase extraction, mixed-mode liquid chromatography-high resolution accurate mass spectrometry (LC-HRMS), peak detection, feature reduction and compound identification. The novel use of an ammonium bicarbonate-based elution solvent extended strong anion-exchange solid-phase extraction applicability to LC-HRMS of strong acids. This approach performed with consistently higher recovery and repeatability (88 ± 7 % at 500 ng L-1), improved selectivity and lower matrix interference (mean = 12 %) over a generic mixed-mode weak anion exchange SPE method. In addition, a novel filter for reducing full-scan features from fulvic and humic acids was successfully introduced, reducing workload and potential for false positives. The workflow was then applied to 10 London municipal drinking water samples, revealing the presence of 22 confirmed and 37 tentatively identified substances. Several poorly investigated and potentially harmful compounds were found which included halogenated hydroxy-cyclopentene-diones and dibromomethanesulfonic acid. Some of these compounds have been reported as mutagenic in test systems and thus their presence here requires further investigation. Overall, this approach demonstrated that employing selective extraction improved detection and helped shortlist suspects and potentially toxic chemical contaminants with higher confidence.

Polycyclic aromatic hydrocarbons (PAHs) are considered priority hazardous substances due to their carcinogenic activity and risk to public health. Strict regulations are in place limiting their release into the environment, but enforcement is hampered by a lack of adequate field-testing procedure, instead relying on sending samples to centralised analytical facilities. Reliably monitoring levels of PAHs in the field is a challenge, owing to the lack of field-deployable analytical methods able to separate, identify, and quantify the complex mixtures in which PAHs are typically observed. Here, we report the development of a hand-portable system based on high-performance liquid chromatography incorporating a spectrally wide absorption detector, capable of fingerprinting PAHs based on their characteristic spectral absorption profiles: identifying 100% of the 24 PAHs tested, including full coverage of the United States Environmental Protection Agency priority pollutant list. We report unsupervised methods to exploit these new capabilities for feature detection and identification, robust enough to detect and classify co-eluting and hidden peaks. Identification is fully independent of their characteristic retention times, mitigating matrix effects which can preclude reliable determination of these analytes in challenging samples. We anticipate the platform to enable more sophisticated analytical measurements, supporting real-time decision making in the field. Portable liquid chromatography instruments enable a myriad of applications in field research. Here a handportable system incorporating a broadband absorption detector is used to separate and classify polycyclic aromatic hydrocarbons from environmental water samples based solely on spectral fingerprinting.

Thermogalvanic devices can harvest wasted thermal energy; a waste product that is generated by humanity in staggering abundance. However, the incorporation of thermogalvanic devices in applications from hot, industrial environments through to waste body heat harvesting necessitates safe chemicals. In particular, since the redox active ions are the charge carriers the chemistry of these is crucial; the bigger and more powerful the device, the greater the abundance of these chemicals. The anionic ferricyanide/ferrocyanide ([Fe(CN)6]3−/4−) redox couple is arguably the most widely utilised and investigated thermogalvanic electrolyte, but has inherent (in)stability issues, and therefore safety issues. This study has investigated a wide range of anionic polycarboxylate and polyaminocarboxylate ligands in conjunction with iron(II/III) chloride (FeCl2/3) in an effort to develop a safer [Fe(CN)6]3−/4−-replacement. Detailed electrochemical and spectroscopic characterisation was used across the wide range of ligands investigated, and several were found to be viable for use in thermogalvanic cells. In particular, optimised nitriloacetic acid was found to yield a redox-active complex, [Fe(NTA)2]3−/4−, with a good Seebeck coefficient (−1.35 mV K−1) on par with [Fe(CN)6]3−/4−. However, diethylenetriaminepentaacetic acid (to form [Fe(DEPTA)]2−/3−) demonstrated the optimum compromise between thermodynamic and kinetic properties; this was used to prepare an in-series thermogalvanic device with the parent Fe2+/3+ species. Benchmarking against relative costs, and the principles of green chemistry and green chemical engineering was used to identify the relative merits of the different systems.

The synthesis of chiral polyoxometalates (POMs) is a challenge because of the difficulty to induce the formation of intrinsically chiral metal-oxo frameworks. Herein we report the stereoselective synthesis of a series of gigantic chiral Mo Blue (MB) POM clusters 1–5 that are formed by exploiting the synergy between coordinating lanthanides ions as symmetry breakers to produce MBs with chiral frameworks decorated with amino acids ligands; these promote the selective formation of enantiopure MBs. All the compounds share the same framework archetype, based on {Mo124Ce4}, which forms an intrinsically chiral Δ or Λ configurations, controlled by the configurations of functionalized chiral amino acids. The chirality and stability of 1–5 in solution are confirmed by circular dichroism, 1H NMR, and electrospray ion mobility–mass spectrometry studies. In addition, the framework of the {Mo124Ce4} MB not only behaves as a host able to trap a chiral {Mo8} cluster that is not accessible by traditional synthesis but also promotes the transformation of tryptophan to kynurenine in situ. This work demonstrates the potential and applicability of our synthetic strategy to produce gigantic chiral POM clusters capable of host–guest chemistry and selective synthetic transformations.

We designed and conducted a series of primordial‐soup Miller‐Urey style experiments with deuterated gases and reagents to compare the spark‐discharge products of a “deuterated world” with the standard reaction in the “hydrogenated world”. While the deuteration of the system has little effect on the distribution of amino acid products, significant differences are seen in other regions of the product‐space. Not only do we observe about 120 new species, we also see significant differences in their distribution if the two hydrogen isotope worlds are compared. Several isotopologue matches can be identified in both, but a large proportion of products have no equivalent in the corresponding isotope world with ca. 43 new species in the D world and ca. 39 new species in the H world. This shows that isotopic exchange (the addition of only one neutron) may lead to significant additional complexity in chemical space under otherwise identical reaction conditions.

Wir berichten hier uber ein hybrides organisch-anorganisches Polyoxometallat, Na2[(HGMP)2Mo5O15]⋅7 H2O (1) (mit GMP=Guanosinmonophosphat), das sich spontan zu einer Struktur zusammenfugt, deren Dimensionen jenen der naturlich vorkommenden linkshandigen Z-Form der DNA verbluffend ahnlich sind. Die Helixparameter in der Kristallstruktur dieser neuen Verbindung, wie Anstieg pro Windung und helikale Verdrillung pro Dimer, sind nahezu identisch zur DNA, was einen eingehenden Vergleich von beiden Strukturen erlaubt. Zirkulardichroismus (CD) in Losung zeigt, dass Verbindung 1 auch in Losung ausgedehnte Sekundarstrukturen aufweist. Gelelektrophorese-Untersuchungen weisen die Bildung nichtkovalenter Addukte mit naturlichen Plasmiden nach. Damit konnen wir einen Weg aufzeigen, auf dem einfache, hybride organisch-anorganische Monomere, wie in Verbindung 1, sich spontan zu einer Doppelhelix zusammenlagern konnen, ohne dass dazu eine kovalent gebundene lineare Sequenz von Nuklein-Saure-Base-Paaren notig ware.

Herein, we report a hybrid polyoxometalate organic–inorganic compound, Na2[(HGMP)2Mo5O15]⋅7 H2O (1; where GMP=guanosine monophosphate), which spontaneously assembles into a structure with dimensions that are strikingly similar to those of the naturally occurring left-handed Z-form of DNA. The helical parameters in the crystal structure of the new compound, such as rise per turn and helical twist per dimer, are nearly identical to this DNA conformation, allowing a close comparison of the two structures. Solution circular dichroism studies show that compound 1 also forms extended secondary structures in solution. Gel electrophoresis studies demonstrate the formation of non-covalent adducts with natural plasmids. Thus we show a route by which simple hybrid inorganic–organic monomers, such as compound 1, can spontaneously assemble into a double helix without the need for a covalently connected linear sequence of nucleic acid base pairs.

Engineering self-templating inorganic architectures is critical for the development of bottom-up approaches to nanoscience, but systems with a hierarchy of templates are elusive. Herein we describe that the cluster-anion-templated (CAT) assembly of a {CAT}⊂{Mo24 Fe12 } macrocycle forms a giant ca. 220 nm(3) unit cell containing 16 macrocycles clustered into eight face-shared tetrahedral cluster-of-clusters assemblies. We show that {CAT}⊂{Mo24 Fe12 } with different CATs gives the compounds 1-4 for CAT=Anderson {FeMo6 } (1), Keggin {PMo12 } (2), Dawson {P2 W18 } (3), and {Mo12 O36 (HPO3 )2 } (4) polyoxometalates. "Template-free" assembly can be achieved, whereby the macrocycle components can also form a template in situ allowing template to macrocycle to superstructure formation and the ability to exchange the templates. Furthermore, the transformation of template clusters within the inorganic macrocycle {Mo24 Fe12 } allows the self-generation of an uncapped {Mo12 O36 (HPO3 )2 } in compound 4.

Many high-yielding reactions for forming peptide bonds have been developed but these are complex, requiring activated amino-acid precursors and heterogeneous supports. Herein we demonstrate the programmable one-pot dehydration–hydration condensation of amino acids forming oligopeptide chains in around 50% yield. A digital recursive reactor system was developed to investigate this process, performing these reactions with control over parameters such as temperature, number of cycles, cycle duration, initial monomer concentration and initial pH. Glycine oligopeptides up to 20 amino acids long were formed with very high monomer-to-oligomer conversion, and the majority of these products comprised three amino acid residues or more. Having established the formation of glycine homo-oligopeptides, we then demonstrated the co-condensation of glycine with eight other amino acids (Ala, Asp, Glu, His, Lys, Pro, Thr and Val), incorporating a range of side-chain functionality., Typically, in order to form large peptides, complex procedures or activating agents are required. Here, the authors show that simple aqueous conditions with dehydration-hydration cycles are sufficient for the oligomerization of amino acids into peptides (up to 20 amino acids long) in yields of up to 50%.

Here we report a suite of approaches for the isolation of asymmetrically grafted organic–inorganic hybrid\ud Mn–Anderson polyoxometalate compounds (TBA)3[MnMo6O18((OCH2)3CNHR1)((OCH2)3CNHR2)] (where\ud TBA ¼ tetrabutylammonium). Both a “pre-functionalization” route (for compound 1 – R1 ¼ –COC14H9,\ud R2 ¼ –H) using two different TRIS-based ligands ((HOCH2)3CNHR), and a “post-functionalization” of the\ud preformed TRIS Mn–Anderson compound (R1 ¼ R2 ¼ –H) were demonstrated. Compounds 2 (R1 ¼\ud –COC15H31, R2 ¼ –CO(CH2)2COOH) and 3 (R1 ¼ –COC15H31, R2 ¼ –H) are some of the first reported\ud examples of asymmetric Mn–Anderson compounds to have been synthesized by the latter route. The\ud reliable and broadly applicable chromatographic method used to isolate these compounds relies on the\ud difference in affinity of compounds' organic moieties for reverse phase (RP) media; the target\ud asymmetric cluster will have an intermediate affinity, between that of the two symmetric by-products.\ud For instances where this is not the case, we have prepared and isolated a “universal” asymmetric Mn–\ud Anderson precursor 4 (R1 ¼ –C(O)OC14H11, R2 ¼ –H), which can be used as a precursor to synthesize\ud practically any asymmetric Mn–Anderson system. The use of 4 as an “universal” precursor was\ud successfully demonstrated in the synthesis and isolation of compound 5 (R1 ¼ –COC2H5, R2 ¼ –H), which\ud would not be accessible by a simple ‘one pot’ approach. In addition to removing a significant barrier to\ud the exploitation of asymmetric Mn–Anderson clusters as new functional materials, the methods\ud presented here should be applicable to a range of other hybrid organic–inorganic clusters.

We report the preparation and characterization of two new polyoxothiometalate species, {Mo16} = {(Mo2O2S2)8(OH)16(C4O4)2}(4-) (compound 1) and {Mo12} = {(Mo2O2S2)6(OH)12(CH3COO)2}(2-) (compound 2). Control of synthesis is achieved by the addition of the organic-template and further re-arrangement is controlled simply by the addition of potassium to a precursor compound yielding compound 2. The structures of the compounds are discussed and we also show that ion-mobility mass spectrometry can be used to resolve the species and their building blocks in solution.

The {Pd84 }(Ac) wheel, initially discovered serendipitously, is the only reported giant palladium macrocycle-a unique structure that spontaneously assembles from small building blocks. Analogues of this structure are elusive. A new modular route to {Pd84 }(Ac) is described, allowing incorporation of other ligands, and a new screening approach to cluster discovery. Structural assignments were made of new species from solution experiments, overcoming the need for crystallographic analysis. As a result, two new palladium macrocycles were discovered: a structural analogue of the existing {Pd84 }(Ac) wheel with glycolate ligands, {Pd84 }(Gly) , and the next in a magic number series for this cluster family-a new {Pd72 }(Prop) wheel decorated with propionate ligands. These findings confirm predictions of a magic number rule for the family of {Pdx } macrocycles. Furthermore, structures with variable fractions of functional ligands were obtained. Together these discoveries establish palladium clusters as a new class of tunable nanostructures. In facilitating the discovery of species that would not have been discovered by orthodox crystallization approaches, this work also demonstrates the value of solution-based screening and characterization in cluster chemistry, as a means to decouple cluster formation, discovery, and isolation.

Significance We show that materials with different structure and function can emerge from the same starting materials under different environmental conditions, such as order of reactant addition or inclusion of minerals. The discoveries we report were made possible by using analytical tools more common in omics/systems biology for functional and structural characterization, retasked for exploring and manipulating complex reaction networks. We not only demonstrate that environments can differentiate fixed sets of starting materials (both mixtures of pure amino acids and the classic Miller–Urey “prebiotic soup” model), but that this has functional consequences. It has been often said that biology is “chemistry with history” and this work shows how this process can start., Many approaches to the origin of life focus on how the molecules found in biology might be made in the absence of biological processes, from the simplest plausible starting materials. Another approach could be to view the emergence of the chemistry of biology as process whereby the environment effectively directs “primordial soups” toward structure, function, and genetic systems over time. This does not require the molecules found in biology today to be made initially, and leads to the hypothesis that environment can direct chemical soups toward order, and eventually living systems. Herein, we show how unconstrained condensation reactions can be steered by changes in the reaction environment, such as order of reactant addition, and addition of salts or minerals. Using omics techniques to survey the resulting chemical ensembles we demonstrate there are distinct, significant, and reproducible differences between the product mixtures. Furthermore, we observe that these differences in composition have consequences, manifested in clearly different structural and functional properties. We demonstrate that simple variations in environmental parameters lead to differentiation of distinct chemical ensembles from both amino acid mixtures and a primordial soup model. We show that the synthetic complexity emerging from such unconstrained reactions is not as intractable as often suggested, when viewed through a chemically agnostic lens. An open approach to complexity can generate compositional, structural, and functional diversity from fixed sets of simple starting materials, suggesting that differentiation of chemical ensembles can occur in the wider environment without the need for biological machinery.