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In this study, ionic liquids were used for the selective extraction/isolation of hemoglobin from human serum for cotinine determination using the ELISA Kit. The suitability of hydrophobic imidazolium-based ionic liquids was tested, of which OMIM BF4 (1-methyl-3-octylimidazolium tetrafluoroborate) turned out to be the most suitable for direct extraction of hemoglobin into an ionic liquid without the use of any additional reagent at one extraction step. Hemoglobin was separated quantitatively (95% recovery) from the remaining types of proteins remaining in the aqueous phase. Quantum mechanical calculations showed that the interaction of the iron atom in the heme group and the nitrogen atom of the ionic liquid cation is responsible for the transfer of hemoglobin whereas molecular dynamics simulations demonstrated that the non-covalent interactions between heme and solvent are more favorable in the case of OMIM BF4 in comparison to water. The opposite trend was found for cotinine. Selective isolation of the heme/hemoglobin improved the ELISA test's accuracy, depending on the cotinine level, from 15% to 30%.
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Hemo , Líquidos Iónicos , Humanos , Cotinina , Hemoglobinas , Ensayo de Inmunoadsorción Enzimática , AguaRESUMEN
The routine techniques currently applied for the determination of nicotine and its major metabolites, cotinine, and trans-3'-hydroxycotinine, in biological fluids, include spectrophotometric, immunoassays, and chromatographic techniques. The aim of this study was to develop, and compare two new chromatographic methods high-performance liquid chromatography coupled to triple quadrupole mass spectrometry (HPLC-QQQ-MS/MS), and RP-HPLC enriched with chaotropic additives, which would allow reliable confirmation of tobacco smoke exposure in toxicological and epidemiological studies. The concentrations of analytes were determined in human plasma as the sample matrix. The methods were compared in terms of the linearity, accuracy, repeatability, detection and quantification limits (LOD and LOQ), and recovery. The obtained validation parameters met the ICH requirements for both proposed procedures. However, the limits of detection (LOD) were much better for HPLC-QQQ-MS/MS (0.07 ng mL-1 for trans-3'-hydroxcotinine; 0.02 ng mL-1 for cotinine; 0.04 ng mL-1 for nicotine) in comparison to the RP-HPLC-DAD enriched with chaotropic additives (1.47 ng mL-1 for trans-3'-hydroxcotinine; 1.59 ng mL-1 for cotinine; 1.50 ng mL-1 for nicotine). The extraction efficiency (%) was concentration-dependent and ranged between 96.66% and 99.39% for RP-HPLC-DAD and 76.8% to 96.4% for HPLC-QQQ-MS/MS. The usefulness of the elaborated analytical methods was checked on the example of the analysis of a blood sample taken from a tobacco smoker. The nicotine, cotinine, and trans-3'-hydroxycotinine contents in the smoker's plasma quantified by the RP-HPLC-DAD method differed from the values measured by the HPLC-QQQ-MS/MS. However, the relative errors of measurements were smaller than 10% (6.80%, 6.72%, 2.04% respectively).
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Cromatografía Líquida de Alta Presión/métodos , Cromatografía Liquida/métodos , Cotinina/análogos & derivados , Cotinina/sangre , Nicotina/sangre , Fumar/sangre , Espectrometría de Masas en Tándem/métodos , Humanos , Límite de Detección , Polonia/epidemiología , Fumar/epidemiologíaRESUMEN
Background: Identification and quantitative determination of cytisine, especially in biological samples and pharmaceutical formulations, is still a difficult analytical task. Cytisine is an alkaloid with a small and very polar molecule. For this reason, it is very weakly retained on reversed phase (RP) stationary phases, such as commonly used alkyl-bonded phases. The very weak retention of cytisine causes it to be eluted together with the components of biological matrices. Objective: Comparison and evaluation of various chromatographic systems for analysis of cytisine in different matrices-serum, saliva and pharmaceutical formulation-by high performance liquid chromatography (HPLC) with diode array (DAD), fluorescence (FLD) and mass spectrometry (MS) detection. Methods: The analyses were performed using HPLC in reversed phase (RP), hydrophilic interaction liquid chromatography (HILIC) and ion exchange chromatography (IEC) modes. Different sample pre-treatment methods were tested: Protein precipitation (with acetone, methanol (MeOH) or acetonitrile (ACN), and solid phase extraction (SPE) using cartridges with octadecyl (C18), hydrophilic-lipophilic balanced copolymer (HLB) or strong cation exchange sorbents (Strata X-C). Conclusion: Significant differences were observed in retention parameters with a change of the used chromatographic system. The various properties of stationary phases resulted in differences in analyte retention, peaks' shape and systems' efficiency. The weakest retention was observed using RP systems; however, the use of the Polar RP phase can be an alternative for application in green chromatography. In the strongest retention was observed using a strong cation exchange (SCX) phase. The most optimal systems were chosen for the analysis of cytisine in the pharmaceutical preparation, serum and saliva after sample pre-treatment with the new SPE procedure. Due to the sensitivity, the use of HPLC-DAD or HPLC-FLD is the most optimal for drug analysis in pharmaceutical preparations, whereas HPLC-MS is suitable for analysis of cytisine in biological samples.
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Alcaloides/análisis , Preparaciones Farmacéuticas/química , Saliva/química , Suero/química , Azocinas/análisis , Cromatografía Líquida de Alta Presión , Cromatografía por Intercambio Iónico , Fluorescencia , Humanos , Interacciones Hidrofóbicas e Hidrofílicas , Espectrometría de Masas , Quinolizinas/análisisRESUMEN
Selection of livestock has not only led to changes in the level of their performance but also modified their behavior. As a result, within a single species, we have to deal with different behaviors of different breeds. In our study, we assumed that the different behaviors within a species are due to differences in the morphology and physiology of behavior-related systems. Two breeds of hens were used as a model: the highly reactive, fearful and high-performance Leghorn breed and proactive, unselected Green-legged Partridge breed. The higher reactivity and fearfulness of Leghorn hens in comparison to the Green-legged Partridge breed may be related to the greater number of neurons in the paraventricular nucleus and anterior hypothalamus and the higher content of zinc and iron in the brain, as these elements are involved in neuronal conduction and myelination processes. The reactive behaviours of Green-legged Partridge hens may be associated with the lower number of neurons in the paraventricular nucleus and the anterior hypothalamus and the higher concentration of dopamine and copper ions in the brain. The analyses confirmed the hypothesis of the existence of interbreed differences in the morphology and physiology of behaviour-related systems, which most probably emerged through unintentional and correlated selection towards high production performance. Consequently, attention should be drawn that the selection of a given genotype (breed) towards a specific environment could lead to creation of highly specialised lines that may not achieve homeostasis in every maintenance system.
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Conducta Animal , Pollos , Animales , Femenino , Pollos/genética , Conducta Animal/fisiología , Encéfalo , Núcleo Hipotalámico Paraventricular , GenotipoRESUMEN
Postmortem carbon monoxide (CO) and hydrogen cyanide (HCN) diffusion under ambient conditions was assessed in a human cadaver model. The main objective of this study was to determine whether the postmortem diffusion of HCN and CO greatly affected the determination of HCN, carboxyhemoglobin (COHb), and carboxymyoglobin (COMb). Layered samples of blood, musculocutaneous, and muscular specimens were collected from the adult cadavers and placed in the tight chambers designed for the purpose of this experiment. The specimens were treated with CO and HCN for 24 h. COHb and COMb were determined using headspace gas chromatography (GC) with an O-FID detector while the HCN values were assessed using a GC headspace with an NPD detector. It was shown that the skin substantially limited the diffusion of CO which penetrated the superficial layers of the muscle very slightly, all the while not affecting the blood level of COHb in the 4.5 cm layer of the muscle located underneath. There were no differences regarding the CO diffusion between superficially charred and thermally coagulated compared to that observed in intact integuments. In addition, the cutaneous sample deprived of the adipose layer was not shown to be a barrier to the moderate diffusion of CO into the blood layer below. HCN was found to easily diffuse from the skin to the blood vessels (vein specimens), and partial charring and thermocoagulation of the superficial muscular layer favored the diffusion of cyanides into the tissues. Similarly to CO, HCN diffusion to the blood and muscles was greatly limited by the adipose layer.
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Hemp seed (Cannabis sativa L.) contain large amounts of nutrients, e.g. protein, dietary fiber, minerals, and unsaturated fatty acids, which make them a good fortifying component in food production. The aim of the present study was to determine the effect of hemp addition on the physicochemical properties, cooking quality, texture parameters and sensory properties of durum wheat pasta. The samples were fortified with 5-40% of commercially available hemp flour or 2.5-10% of hemp cake obtained from hemp seed oil pressing. Our study showed that the addition of hemp seed raw materials led to an increase in the protein, total dietary fiber (TDF), ash and fat content in the pasta samples. Due to its lower granulation and higher nutritional value, hemp flour was found to be a better raw material for the fortification of pasta than hemp cake. Pasta enriched with hemp flour at the level of 30-40% contains 19.53-28.87% d.m. of protein and 17.02-21.49% d.m. of TDF and according to the EU, a definition can be described as a high-protein and high-fiber products. All enriched pasta samples were also characterized by safe Δ-9-tetrahydrocannabinol (THC) and cannabidiol (CBD) content, and their sensory properties were accepted by consumers.