Storage stability study of metronidazole and hydroxymetronidazole in chicken eggs by liquid chromatography tandem mass spectrometry.

Metronidazole (MNZ) is one of the most commonly used antibiotics in the food industry. High levels in food can lead to the development of antimicrobial resistance in humans, so it is important to monitor its levels in food. In the context of legal proceedings, it is frequently necessary to re-examine samples after an extended period of time.

Preparation, physicochemical characterization and swelling properties of composite hydrogel microparticles based on gelatin and pectins with different structure.

Composite hydrogel microparticles based on pectins with different structures (callus culture pectin (SVC) and apple pectin (AU)) and gelatin were developed. Hydrogel microparticles were formed by the ionotropic gelation and electrostatic interaction of COO groups of pectin and NH groups of gelatin, which was confirmed by FTIR spectroscopy. The addition of gelatin to pectin-based gel formulations resulted in a decrease in gel strength, whereas increasing gelatin concentration enhanced this effect.

Immunotechniques for the Group Determination of Macrolide Antibiotics Traces in the Environment Using a Volume-Mediated Sensitivity Enhancement Strategy.

Macrolide antibiotics, which are effective antimicrobial agents, are intensively used in human and veterinary medicine, as well as in agriculture. Consequently, they are found all over the world as environmental pollutants, causing harm to sensitive ecological communities and provoking a selection of resistant forms. A novel azithromycin derivative, which was used as hapten conjugate, ensured the group immunorecognition of six major macrolide representatives (105-41%), namely erythromycin, erythromycin ethylsuccinate, clarithromycin, roxithromycin, azithromycin, and dirithromycin in a competitive immunoassay based on anti-clarithromycin antibodies.

Rapid multi-residue LC-MS/MS determination of nitrofuran metabolites, nitroimidazoles, amphenicols, and quinolones in honey with ultrasonic-assisted derivatization - magnetic solid-phase extraction.

A rapid multi-residue LC-MS/MS method for the identification and determination of banned veterinary drugs in honey was developed. A total of 31 investigated veterinary drugs belonging to 4 classes including nitrofurans metabolites, nitroimidazoles, amphenicols, and quinolones were quantified by LC-MS/MS with ESI using one single injection. The sample preparation included treatment with 5-nitro-2-furaldehyde (5-NFA) in a thermostated ultrasonic bath (80 °C, 0.

Current trends in analytical strategies for the chromatographic determination of nitrofuran metabolites in food samples. An update since 2012.

Nitrofurans (NFs) are synthetic broad-spectrum antibacterial and antiparasitic drugs, which recently were extensively used in veterinary practice. In the body of animals, NFs are converted into carcinogenic and mutagenic metabolites that can be accumulated in foods of animal origin having an adverse effect on human health. Therefore, NFs are currently banned in animal husbandry and aquaculture of many countries.

Multi-class, multi-residue determination of 132 veterinary drugs in milk by magnetic solid-phase extraction based on magnetic hypercrosslinked polystyrene prior to their determination by high-performance liquid chromatography-tandem mass spectrometry.

A quantitative multi-class multi-residue analytical method was developed for the determination of veterinary drugs in milk by high-performance liquid chromatography - tandem mass spectrometry (HPLC-MS/MS). A total of 132 veterinary drugs investigated belonged to almost 15 classes including sulfonamides, β-lactams, tetracyclines, quinolones, macrolides, nitrofurans, nitroimidazoles, phenicols, lincosamides, pleuromutilins, macrocyclic lactones, quinoxaline antibiotics, benzimidazoles, anthelmintics, coccidiostats and some others. A magnetic solid-phase extraction procedure was developed using magnetic hypercrosslinked polystyrene (HCP/FeO) for the sample preparation prior to HPLC-MS/MS without deproteinization step.

Characterization and Biocompatibility Properties In Vitro of Gel Beads Based on the Pectin and -Carrageenan.

This study aimed to investigate the influence of kappa (κ)-carrageenan on the initial stages of the foreign body response against pectin gel. Pectin-carrageenan (P-Car) gel beads were prepared from the apple pectin and κ-carrageenan using gelling with calcium ions. The inclusion of 0.

Occurrence of fish species in the inland water of Murmansk Region (Russia): research in 1972-2021.

Background: Knowledge about the distribution of organisms on Earth is important backbone of biological sciences and especially for deeper understanding of biogeography. However, much of the existing distributional data are scattered throughout a multitude of sources (including in different languages), such as taxonomic publications, checklists and natural history collections and often, bringing them together is difficult. Development of the digital storage facilities may prevent loss of important data (Ruchin et al.

Determination of nitrofuran metabolites in honey using a new derivatization reagent, magnetic solid-phase extraction and LC-MS/MS.

In this study, 5-nitro-2-furaldehyde (5-NFA) was proposed as a new derivatizing agent for nitrofuran metabolites. It reacts with nitrofuran metabolites producing the parent nitrofurans (furazolidone, furaltadone, nitrofurantoin, and nitrofurazone). Magnetic hypercrosslinked polystyrene (HCP/FeO) was first used for magnetic solid phase extraction (MSPE) clean-up before the determination of nitrofuran metabolite derivatives in honey via LC-MS/MS.

Effect of amines on formation of gold/polyurethane foam nanocomposites and its sensing opportunities.

Effect of amines on formation of gold nanoparticles (AuNPs)/polymer nanocomposites has been observed and studied. Nanocomposites based on polyurethane foam and AuNPs were synthesized by interaction between the polymer modified with sodium borohydride and aqueous solution of tetrachloroauric acid. It has been shown that some amines cause a remarkable decrease of the surface plasmon resonance band of AuNPs in the nanocomposite material.

Preparation and properties of the pectic gel microparticles based on the Zn, Fe and Al cross-linking cations.

The aim of this work was to evaluate the relationship between the cross-linking cation content in the microparticles, chemical characteristics of pectins and swelling properties of the gel microparticles based on the Zn, Fe and Al cross-linking cations. A significant negative correlation between the Zn content and DM of pectin indicated that decreasing DM of pectin promoted Zn binding. The microparticles from the pectins with a higher linearity had a higher content of Fe.

Preparation and release characteristics of mesalazine loaded calcium pectin-silica gel beads based on callus cultures pectins for colon-targeted drug delivery.

The aim of this work is to produce calcium pectin-silica gel beads containing mesalazine as a drug model in order to control the drug release in the colon. The mesalazine loaded calcium pectin-silica gel beads were prepared using the ionotropic gelation method. Energy-dispersive X-ray analysis revealed that increasing the NaSiO concentration led to an increase of the silicon content on the surface and in the cross-sections of the beads.

Adhesive properties of calcium pectinate gels prepared from callus cultures pectins.

The aim of this research is to investigate the influence of the surface morphology of the calcium pectinate gel (CaPG) beads as well as the physicochemical characteristics of pectins and the CaPG beads on the adhesive properties of gels against the Gram-negative bacteria Escherichia coli and the Gram-positive bacteria Bacillus subtilis. The adhesion of the bacteria depends on the type of pectin and the surface morphology of the beads. The faster adhesion on CaPG beads appeared to be related to a lower degree of methyl esterification (DE), a higher molecular weight (Mw) and specific viscosity of the pectin and a higher gel strength.

[Adhesion of Bacillus subtilis on the surface of pectin-calcium gel].

Pectin-calcium gels obtained based on pectins of callus cultures are able to adhere to the surface of cells of Gram-positive bacteria Bacillus subtilis to various degrees and this is thanks to the structural features of pectin. Rapid adhesion of the cells to gels obtained from the pectin of Tanacetum vulgare (TVC) callus cultures is associated with a high content of the linear region in the carbohydrate chain of pectin, a high molecular weight, and a low degree of methyl etherification of pectin. The number of adherent cells on the surface of gels obtained from pectins of Silene vulgaris callus cultures (SVC), TVC, and Lemna minor (LMC) after 8 h of incubation was close, whereas the number of cells was minimal on a gel produced using the pectin of Silene tatarica (STC) callus culture.