Weak anion-exchange hypercrosslinked sorbent in on-line solid-phase extraction-liquid chromatography coupling to achieve automated determination with an effective clean-up

A mixed-mode polymeric sorbent was on-line coupled to liquid chromatography (LC) for the first time and applied it to the selective solid-phase extract a group of pharmaceuticals in complex environmental water samples. The mixed-mode polymeric sorbent is a high-specific surface area hypercrosslinked polymer resin (HXLPP) in the form of monodisperse microspheres further modified with 1,2-ethylenediamine (EDA) moieties. These properties allows its application as a weak anion-exchange (WAX) sorbent in the on-line solid-phase extraction (SPE) coupling. The on-line SPE-LC method developed using the HXLPP-WAX sorbent was successfully applied to percolate a large volume of ultrapure (500 ml), river (250 ml) and effluent sewage (100 ml) water samples. In all the cases, the HXLPP-WAX resin provided near total recoveries of the most acidic compounds studied and clean chromatograms. This is because the ion-exchange interactions enable a washing step to be added to the SPE protocol that removes the compounds with weak acidic, neutral and basic properties from the sample matrix

Synthesis and application of hypercrosslinked polymers with weak cation-exchange character for the selective extraction of basic pharmaceuticals from complex environmental water samples

The synthesis of high specific surface area sorbents (HXLPP-WCX) in the form of hypercrosslinked polymer microspheres with narrow particle size distributions, average particle diameters around 6 µm, and weak cation exchange (WCX) character, is described. The WCX character arises from carboxylic acid moieties in the polymers, derived from the comonomer methacrylic acid. A novel HXLPP-WCX sorbent with an attractive set of chemical and physical properties was then used in an off-line solid-phase extraction (SPE) protocol for the selective extraction of a group of basic compounds from complex environmental samples, a priority being the clean separation of the basic compounds of interest from acidic compounds and interferences. The separation power of the new sorbent for basic pharmaceuticals was compared to two commercially available, mixed-mode sorbents, namely Oasis WCX and Strata X-CW. Under identical experimental conditions, HXLPP-WCX was found to deliver both higher capacity and better selectivity in SPE than either of the two commercially available materials. In an optimised SPE protocol, the HXLPP-WCX sorbent gave rise to quantitative and selective extractions of low µg l-1 levels of basic pharmaceuticals present in 500 ml of river water and 250 ml of effluent waste water

Hydrophilic hypercrosslinked polymeric sorbents for the solid-phase extraction of polar contaminants from water

Three new hypercrosslinked polymers with hydrophilic character arising from hydroxyl moieties in their skeletons have been prepared in microsphere format and applied to the off-line solid-phase extraction (SPE) of polar compounds from water samples. For sample volumes of 1000 ml, the recoveries of various polar pesticides, such as oxamyl, methomyl, selected phenolic compounds, as well as some pharmaceuticals, were close to 90%. The HXLPP-polar polymer with the best performance characteristics was applied to real samples. Its performance was also compared to commercially available sorbents, such as LiChrolut EN (hydrophobic, hypercrosslinked), Oasis HLB (hydrophilic, macroporous) and Isolute ENV+ (hydrophilic, hypercrosslinked); the new sorbent out-performed the commercially available sorbents. The polymer was applied successfully in off-line SPE of river water samples followed by liquid chromatography and ultraviolet detection, providing a good linear range and detection limits of 0.2 μg l-1 for the majority of the compounds, with the exception of oxamyl, methomyl, guaiacol and salicylic acid where the detection limit was 0.5 μg l-1

Hypercrosslinked materials

This chapter describes the chemistry of hypercrosslinked materials, and presents a description of their synthesis, defining physico-chemical features and their most important applications. The synthesis section will examine the different monomers, precursor polymers, reagents and synthetic strategies used to prepare hypercrosslinked materials. Each synthesis section also details the chemical and morphological properties of the hypercrosslinked materials and the main field of application

Hypercrosslinked materials : preparation, characterisation and applications

This review article provides an overview of hypercrosslinking technology. In particular, it covers the preparation and characterisation of hypercrosslinked materials and their applications. The synthesis section examines the different monomers, precursor polymers and reagents used to prepare hypercrosslinked materials, but also the different synthetic approaches disclosed in the literature. The various chemical modification reactions relevant to this area are also reviewed. Several examples of applications for hypercrosslinked materials are described; these applications are grouped into thematic areas such as chromatography, gas storage and the trapping of organic contaminants

Transforming Yekaterinburg into a Safe, Resilient-Smart and Sustainable City

The initiative (since 2014) project described in this paper is a product of a joint innovative research and implementation effort of the Civil Engineering and Architecture Institute, Ural Federal University, the Science and Engineering Centre "Reliability and Safety of Large Systems and Machines", Ural Branch Russian Academy of Sciences (both Yekaterinburg), Start-up OptiCits, Barcelona, Spain and the Old Dominion University, Norfolk, VA, USA. The project is based on using the MAICS convergent technology [1] to create a versatile multi-purpose tool for optimizing the science and art of risk based governance of resilience-smart and sustainable city infrastructure and communities operating in usual and extreme conditions. The tool being developed is tailored to the needs of the City of Yekaterinburg-the capital of the Urals Region and allegedly the third most important and vibrant city of Russia. It is also being offered to the Yekaterinburg City Administration as an every-day decision-support work-tool and addendum to the Strategic Program "Yekaterinburg 2030 - a Safe City"[2] during preparation of the city for winning and conducting the World Expo-2025. Authors believe that the findings of this research would also be useful to the Sverdlovsk Oblast cities of every size and type of communities that inhabit them, including, first and foremost, Nizhny Tagil, Kamensk Uralsky, Serov, Pervouralsk, Revda, Verkhnyaya Pyshma, multiple mono-cities et al. The project also incorporates block-chain technology, smart contracts and digital currency as an effective tool for implementing the project. © 2018 Institute of Physics Publishing. All rights reserved

Multiple assays in a real-time RT-PCR SARS-CoV-2 panel can mitigate the risk of loss of sensitivity by new genomic variants during the COVID-19 outbreak

Objectives: In this study, five SARS-CoV-2 PCR assay panels were evaluated against the accumulated genetic variability of the virus to assess the effect on sensitivity of the individual assays. Design or methods: As of week 21, 2020, the complete set of available SARS-CoV-2 genomes from GISAID and GenBank databases were used in this study. SARS-CoV-2 primer sequences from publicly available panels (WHO, CDC, NMDC, and HKU) and QIAstat-Dx were included in the alignment, and accumulated genetic variability affecting any oligonucleotide annealing was annotated. Results: A total of 11,627 (34.38%) genomes included single mutations affecting annealing of any PCR assay. Variations in 8,773 (25.94%) genomes were considered as high risk, whereas additional 2,854 (8.43%) genomes presented low frequent single mutations and were predicted to yield no impact on sensitivity. In case of the QIAstat-Dx SARS-CoV-2 Panel, 99.11% of the genomes matched with a 100% coverage all oligonucleotides, and critical variations were tested in vitro corroborating no loss of sensitivity. Conclusions: This analysis stresses the importance of targeting more than one region in the viral genome for SARS-CoV-2 detection to mitigate the risk of loss of sensitivity due to the unknown mutation rate during this SARS-CoV-2 outbreak

Core-shell polymer microspheres with strong cation-exchange character for the extraction of basic pharmaceuticals from aqueous samples

The application of core-shell materials as packing materials for liquid chromatography columns is common in analytical chemistry, however their use as sorbents in solid-phase extraction (SPE) is surprisingly underexplored. In the present study, core-shell polymer microspheres with strong cation-exchange character were designed and synthesized. These new materials benefit from having hypercrosslinked and relatively thin functional shells, which raises the specific surface areas and sorption capacities of the sorbents and allows for relatively shorter diffusion path lengths for analytes. The core-shell polymer microspheres were evaluated as SPE sorbents for the extraction of basic pharmaceuticals from environmental water samples. Following optimization of the pH and volume of the loading solution, as well as optimization of the loading step, the SPE method was validated in terms of apparent and relative recoveries, matrix effect, limits of detection and quantification and precision. The method yielded very promising results in terms of apparent recoveries (>39%) and matrix effect (<±29%) and was applied successfully to the determination of basic pharmaceuticals in environmental water samples (river water, effluent wastewater and influent wastewater)

Comercio protohistórico: el registro del Nordeste peninsular y circulación de mineral de plomo en Ibiza y el Bajo Priorato (Tarragona)

Our recent research shows that lead from the Baix Priorat (Tarragona) mining area circulated in the Phoenician-Tartessian sphere. However, archaeometallurgical analysis of a group of ore and metallic samples from the island of Ibiza reveals the exploitation of local galena, whose use co-existed on the sa Caleta site with ores from Cartagena; on the other hand, lead from the Priorat mining area is not attested. If we also take into account the information provided by 7th-6th centuries BC pottery from Ibiza and Catalonia, a variety of trade networks between the south and the north-east of Iberia emerges