Today, great emphasis is placed on the search for and dissemination of native plant materials in various industries, with particular emphasis on food, cosmetics, dietary supplements, and as livestock feed and a source of biomass. Solid-liquid extraction (SLE), solid phase extraction (SPE), and ultra-high-performance liquid chromatography coupled with tandem mass spectrometry (UHPLC-MS/MS) methods were developed for the simultaneous determination of 30 flavonoids and phenolic acids in plant materials (lucerne (Medicago sativa L.), goldenrod (Solidago virgaurea L.), phacelia (Phacelia tanacetifolia Benth.), buckwheat (Fagopyrum esculentum), licorice (Glycyrrhiza glabra), and lavender (Lavandula spica L.)). Different SLE methods were tested to evaluate their applicability for the isolation of polyphenols from plants. Then extracts were purified with a C18 reversed-phase SPE cartridge. After extraction, samples were analyzed by UHPLC-MS/MS. The SLE-SPE-UHPLC-MS/MS assay method has been fully validated. For the most compounds, good recoveries and RSDs (< 10%) were obtained. Limits of quantification range from 0.4 to 20 ng/mL. The main phenolic acids in the studied plants have been found to be 3-(4-hydroxyphenyl)propionic acid, 4-hydroxybenzoic acid, and 3,4-dihydroxybenzoic acid. Quercetin, rutin, glabridin, and naringenin are the major flavonoids detected in the analyzed samples. The obtained scientific data can be useful to select plant materials with high nutritional value and the presence of many biologically active ingredients, as well as selecting samples used as a plant biomass, as food, and as a component of dietary supplements.
A SPE-UHPLC-UV method for the determination of 13 pharmaceuticals from different therapeutic groups in surface water and wastewater samples was proposed. The following three solid-phase-extraction (SPE) columns with polymeric sorbents were used as a pre-concentration step: the Oasis HLB (average recoveries 93.8 %), the Nexus (84.0 %) and the Bond Elut ENV (88.3 %). A reverse-phase UHPLC with a C18e monolithic column and gradient elution program was used to obtain the best separations for all 13 drugs in short analysis time (3.4 min). The LOD range for determined drugs was 0.02–0.18 μg L−1, and the concentration range for drugs found in water samples was 0.06–0.90 μg L−1. The proposed method was used to analyze different water samples, mostly from rivers, and can be used as a monitoring tool for environmental pollution.
Analytical procedures for the determination of pharmaceuticals from different therapeutic groups were proposed. These groups included the corticosteroids prednisolone and dexamethasone; the β-blockers sotalol, metoprolol, propranolol, and carvedilol; and the analgesic nonsteroidal antiinflammatory drugs paracetamol, aspirin, metamizole, and ketoprofen. Reversed-phase ultrahigh performance liquid chromatography with an ultraviolet detector, different columns, different mobile phases, and gradient elution programmes were used to obtain the best separations within the shortest possible time. Solid-phase extraction was examined as a preconcentration step. The Oasis HLB column, with the highest recoveries (over 90% for most of the drugs), was chosen for the analysis of surface waters. Limits of detection ranged from 0.06 to 0.39 μg L −1 for all drugs after optimisation of all analytical steps.
The calorimetric measurements were applied in testing the wastes collected from different furnaces in electric power plants as materials to be used in civil engineering. The fly ash materials were collected from two power stations based on different brown coal deposits and working with conventional and fluidized bed installation. The reactivity of high calcium fly ash from sub-bituminous coal combustion has been proved in calorimetric, conductometric, chemical shrinkage, and rheological measurements before their practical implementation on larger scale. Highly soluble components of fly ash contribute to the hydration products and structure formation, followed by setting and hardening of fly ash-cement mixture. These results have been the base of research project aimed in the innovative solutions dealing with the management of deposits of wastes generated as a result of coal combustion. The standardization and potential use on larger scale of these materials, necessary from the environmental point of view, seems to be the question of nearest future.
An analytical procedure for the determination of 10 drugs belonging to three different therapeutic groups was analysed. Several compounds were investigated which comprise of beta-blockers: sotalol (SOT), metoprolol (MET), propranolol (PRO), carvedilol (CAR); corticosteroids: prednisolone (PRE), dexamethasone (DEX); analgesic, non-steroidal anti-inflammatory (NSAID): paracetamol (PAR), metamizole (MTZ), aspirin (ASP) and ketoprofen (KET). Reversed-phase liquid chromatography with gradient elution, fluorescence (FL) and diode array detectors (DAD) was applied for the selective investigation of the drugs. Three solvents were used as the mobile phase: methanol, 0.05% trifluoroacetic acid (TFA) in water and acetonitrile. The solid phase extraction (SPE) method using the Oasis HLB column was proposed for the preconcentration step. The recovery level for most of the drugs was above 80%. The low values of limits of detection (LOD) for PAR, SOT, MTZ, MET, SAL, PRO, PRE, CAR, DEX and KET were achieved: 106 ng L(-1), 1,048 ng L(-1), 2.48 ng L(-1), 2.17 ng L(-1), 16.5 ng L(-1), 1.10 ng L(-1), 160 ng L(-1), 6.62 ng L(-1), 76.5 ng L(-1) and 45.2 ng L(-1), respectively. The suggested method was used for the determination of drugs in spiked surface water.
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