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Ionic liquid matrices have been recognized for MALDI application since 2001. However, specific information about the physical and chemical properties, ionicity or proper nomenclature of new matrices has never been presented. The aim of this investigation was to determine the chemical and physical characteristics of ionic matrices using spectroscopic techniques (UV–Vis, IR, 1H NMR). 66 mixtures of acids (standard MALDI matrices) and bases (organic amines) were prepared. The results obtained show that 1H NMR analysis, with supporting information from IR analysis, was helpful in the determination of the ionic character of the new matrices. Furthermore, thermogravimetric and cryometric analyses enabled the examination of the melting and decomposition points, in addition to the physical state of the obtained products, necessary for the classification of the new matrices. As a result, only a few acid and base mixtures could be categorized as ionic liquid matrices. What is important is that there were liquid matrices without an ionic character, and solid matrices with an ionic character. Thereby, a new categorization of matrices was introduced. Unlabelled Image • 12 of 66 acid-base mixtures tested had been found as ILMs. • 1H NMR and IR spectroscopy are good tool for investigation of ILMs. • The ionic products were not always liquid, and vice versa. • The 3.63 of ΔpKa (base vs acid) was enough to create ILMs. • A new nomenclature of MALDI matrices was proposed. [ABSTRACT FROM AUTHOR]

Ionic liquids (ILs) are new-generation, non-volatile solvents which are designable, and their structure may be specifically adjusted to the current application needs. Therefore, it is possible to create and apply ILs which efficiently and selectively extract various analytes from different matrices. It has already been examined that ILs may be applied as receiving phases in passive sampling for the long-term water monitoring of PAHs and pharmaceuticals in water. In this paper, the concept of passive sampling with ILs (PASSIL applied as receiving phases) was continued and developed using phosphonium-, imidazolium-, and morpholinium-cation-based ILs. The target group of analytes was pharmaceuticals which represent one of the most common categories of water contaminants. Fourteen-day-long extractions using various ILs were performed in stirred conditions at a constant temperature (20 °C). The best extraction efficiency was achieved for trihexyl(tetradecyl)phosphonium dicyanamide ([P666-14][N(CN)]). For this preliminary calibration, the sampling rates were calculated for each sulfonamide. Once again, selectivity was observed in passive sampling using [P666-14][N(CN)]. Therefore, PASSIL is seen as a very promising method for pharmaceutical monitoring in water. [ABSTRACT FROM AUTHOR]

Passive sampling is one of the most efficient methods of monitoring pharmaceuticals in environmental water. The reliability of the process relies on a correctly performed calibration experiment and a well-defined sampling rate (Rs) for target analytes. Therefore, in this review the state-of-the-art methods of passive sampler calibration for the most popular pharmaceuticals: antibiotics, hormones, β-blockers and non-steroidal anti-inflammatory drugs (NSAIDs), along with the sampling rate variation, were presented. The advantages and difficulties in laboratory and field calibration were pointed out, according to the needs of control of the exact conditions. Sampling rate calculating equations and all the factors affecting the Rsvalue – temperature, flow, pH, salinity of the donor phase and biofouling – were discussed. Moreover, various calibration parameters gathered from the literature published in the last 16 years, including the device types, were tabled and compared. What is evident is that the sampling rate values for pharmaceuticals are impacted by several factors, whose influence is still unclear and unpredictable, while there is a big gap in experimental data. It appears that the calibration procedure needs to be improved, for example, there is a significant deficiency of PRCs (Performance Reference Compounds) for pharmaceuticals. One of the suggestions is to introduce correction factors for Rsvalues estimated in laboratory conditions. [ABSTRACT FROM AUTHOR]

• The ionicity of ILMs was tested by experimental and calculation methods. • The ionicity was found to be varied between matrices and driven by several factors. • The intermolecular interactions were found to have a great impact on ionicity. • The retro -proton transfer at a high temperature was determined. Ionic liquid matrices (ILMs) have been applied for MALDI-MS analysis for more than 20 years. Despite this, there is still insufficient knowledge regarding their properties. In this work, we tested the ionicity of selected ILMs and discussed their impact on the MALDI process. The targets were the following mixtures: CHCA/TEA, FER/TEA, HABA/α-MBA, 2,5-DHB/α-MBA (CHCA - α-cyano-4-hydroxycinnamic acid, FER – ferulic acid, HABA − 2-(4-hydroxyphenylazo)benzoic acid, 2,5-DHB − 2,5-dihydroxybenzoic acid, TEA – triethylamine, α-MBA - α-methylbenzylamine). These are ILMs which in our previous study showed liquidity at room temperature. We decided to apply several empirical and theoretical techniques due to the complexity of the problem. Thermogravimetric analysis (TGA) with IR was used to test the process at a higher temperature (simulation of a laser shot). 1H NMR was used for the determination in pure ILMs of intermolecular interactions, which have a high impact on ionicity. Conductivity and rheological measurements were performed to determine the Walden plot, from which the excess of ionicity can be concluded. DFT calculations were used to support the statements of dissociation processes in the gas phase and solution. The auto-ionization of matrices in MALDI was also tested. The interpretation of the Walden plot shows that HABA/α-MBA is a very good ionic liquid, which can be derived from a proposed "pedal motion"-like mechanism. The ionicity of other matrices was reduced because of intermolecular interactions (proved by TGA-IR and 1H NMR). The MALDI-MS analysis shows that the obtained mass spectra, namely the base peaks, depend on amine gas proton affinity. Furthermore, the DFT calculation results and the TGA-IR analysis support the mechanism of retro -proton transfer after the laser shot in the gas phase. Finally, it was concluded that the four tested ILMs are differentiated in ionicity, but its extent has no impact on the auto-ionization of the matrix. [ABSTRACT FROM AUTHOR]

• The number of small molecules analyzed by MALDI MS using ILM is relatively low. • The highlighted advantages were reported for rather low number of ILMs. • The lower time of MALDI analysis can be achieve thanks to the ILMs application. • Often higher laser energy was needed for effective ionization supported by the ILMs. • Guidelines for the selection of ILMs for a specific task are awaiting to be presented. Ionic liquid matrices (ILMs) were introduced almost 20 years ago as alternatives to crystal matrices for MALDI MS analysis. They are protic ionic liquids synthesized by mixing conventional acidic MALDI matrices with an equimolar number of organic amines. They have certain advantageous attributes, such as: i. high homogeneity of the matrix + sample mixture, which increases the shot-to-shot reproducibility, ii. reducing the background on mass spectra, which is why molecules with low masses can be analyzed, and iii. the possibility of the quantitative analysis of small molecules. This review aims to present updated reports on the applicability of ILMs for the quantification of small molecules, and to critically discuss the features therein. The number of reports presenting quantitative analysis using ILMs is relatively small, despite the wide range of synthesized ILMs. Various representatives of small peptides, amino acids, pharmaceuticals, drugs, oligosaccharides, alkaloids and toxins were analyzed using ILMs based on DHB and CHCA acids. Furthermore, ILMs were found to be applicable for the imaging and mapping of lipids and small peptides. Even relatively similar ILMs vary from one another due to their ionization potential (intensity of signals in positive and negative ion extraction mode, fragmentation rate, adduct formation). Currently, there are no guidelines for the selection of ILMs for a specific task, which would appear to be a milestone in the application of ILMs for MALDI MS. [ABSTRACT FROM AUTHOR]

In the presented study, the applicability of four sorbent materials (active carbon, neutral alumina, Primary and Secondary Amines (PSA), and Florosil) applied on top of a polymeric Strata-X column was tested to improve the solid-phase extraction of 15 analytes (pharmaceuticals and estrogens) from water. Deionized water and water fortified by humic acids (representatives of dissolved organic matter) were the tested matrices. The effect of water acidification was tested as well. The values of recovery show that sorbents often have different sorption features towards pharmaceuticals with acidic and basic functional groups. PSA shows sorption towards humic acids, thereby can minimize the matrix effect obtained during final quantification by chromatographic techniques coupled with mass spectrometry. The slight sorption of basic pharmaceuticals to humic acids was found out. Finally, a mixture of PSA and alumina was used, and the validated SPE-GC/MS(SIM) method was applied for raw and treated wastewater. A triple-sorbent solid-phase extraction cause lower matrix effect compared to the previous study. This small innovation in the SPE procedure (without any significant cost enhancement and extension of the duration) can have an impact on the quantification of the pharmaceuticals and estrogens, and improve the reliability of the results. • Four sorbents were applied on top of a polymeric SPE column. • Active carbon was discarded; Florosil showed sorption towards basic analytes. • PSA effectively adsorbed humic acids, reducing the matrix effect. • Humic acids affected the recovery of basic analytes (β-blockers, antidepressants). • Finally, Strata-X + PSA + Alumina were used for the screening of analytes in wastewater. [ABSTRACT FROM AUTHOR]

Graphical abstract Abstract The application of biochar (BC) in various fields of engineering, agriculture and environmental protection demands the task-specific adjustment of the surface characteristics of the carbon material. Polar moieties are those elements which distinguish BC from regular carbon black. The knowledge of polar moieties on the surface of the BC is crucial for its application for polar pollutants removal and resistance of nutrients. In this paper several techniques were applied for the verification of polar moieties of crop-derived biochars (both straw and grain) by several techniques (SBET, FTIR, SEM, EDS, pH PZC , elemental analysis). The characterization was also made for washed BCs. It was found that this carbon material is rich in polar moieties, mostly hydroxyl groups and oxides, the latter being washed away together with salts. The high oxygen content decreased after washing (>15%). The values of pH ZPC do not differ between the tested BCs, were in the range of 2.2 to 2.0, and were not changed after the washing of BCs. Thanks to the SBET isotherm analysis, irreversible changes in the material structure by water adsorption were proven. The oxygen content in the surface of BCs can be changed after a very brief time of exposition to natural water or soil with no change in the surface charge. Still, the biochar derived from cereals is a useful material for application in environmental protection purposes. [ABSTRACT FROM AUTHOR]

In this study, biochars (BCs) produced from crops (straw and seeds) were tested for the applicability as additive to soils. The effect on pH, water capacity and cation exchange capacity of soil were tested. The ability for the sorption of pharmaceuticals (beta-blockers, anti-inflammatory drugs, sulfonamides, 17α-ethinylestradiol, carbamazepine, caffeine) using the batch sorption test was performed, and the effect of water pH was investigated. In addition, the metals removed from the biochar was analyzed as a potential toxicity factor. The mechanism of adsorption (Langmuir, Freundlich) was tested for sulfadimetoxine. The effect of the rye-derived biochar on water cress germination and the reduction of the sulfonamides toxicity to this plant was tested. The advantages of crop-derived biochar application to different soils (sand soil, clay soil and reference soil) was presented. It was found that tested BCs effectively increase the water capacity of soils, especially sand type soil, but in the same time it had increase the pH of pure-buffering soils. The driving force of pharmaceutical sorption was its ionization form - the highest sorption occurs for cations, medium for neutral forms, while the lowest sorption for anions. The opposite situation have been noted for desorption from biochar. The washing of biochars increases sorption for the neutral and anionic species, but not for the cations. The application of biochars into the soils can from one site protect the plants from toxic impact of sulfonamides, but from the other hamper the root prolongation by the pH increase. Image 1 • Crop-derived biochar show sorption toward cationic pharmaceuticals. • The mechanism of sulfonamides sorption was checked. • The amendment of soil by biochar decrease the toxicity of sulfonamides to cress. • The toxic effect of biochar to cress by the pH increase was observed. [ABSTRACT FROM AUTHOR]