Extraction of Penicillin G From Dairy Products Using Deep Eutectic Solvent/Alginate Beads Enhanced via Layered Double Hydroxides.

A new nanocomposite based on alginate microbeads impregnated with novel strontium-aluminum layered double hydroxide (Sr-Al LDH) incorporated with choline chloride-urea deep eutectic solvent (ChCl-U DES) was introduced. The microbeads and LDH were characterized by adsorption/desorption isotherms, Fourier-transform infrared spectroscopy, SEM, and x-ray diffraction. The adsorbent was employed for determining penicillin G (PENG) using dispersive solid-phase extraction prior to HPLC analysis.

An alginate-based eutectogel impregnated with polyvinylpyrrolidone/benzoic acid deep eutectic solvent and magnetic carboxylated multiwalled carbon nanotubes: Evaluated as sorbent in green microextraction of pesticides.

This article presents the synthesis and application of a novel magnetic eutectogel constituting a polymeric deep eutectic solvent (PDES), carboxylated multiwall carbon nanotube (MWCNT-COOH), and super-dispersible/super-paramagnetic polyvinylpyrrolidone coated-FeO nanocrystals incorporated in alginate gel. Different methods were used for the characterization of novel polymeric based DES gel including FT-NMR, ATR-FTIR, and SEM were used. The novel DES eutectogel was used for the extraction of pesticides from honey.

Synthesis of a magnetic micro-eutectogel based on a deep eutectic solvent gel immobilized in calcium alginate: Application for green analysis of melamine in milk and dairy products.

A new three-component magnetic eutectogel composed of a crosslinked copolymeric deep eutectic solvent (DES) and polyvinylpyrrolidone-coated FeO nano-powder impregnated in calcium alginate gel was synthesized and applied as a sorbent material in a green alternative micro solid-phase extraction of melamine in milk and dairy products. The analyses were performed using the HPLC-UV technique. The copolymeric DES was prepared through thermally-induced free-radical polymerization of [2-hydroxyethyl methacrylate]:[thymol] DES (1:1 mol ratio) as functional monomer, azobisisobutyronitrile (as initiator), and ethylene glycol dimethacrylate (as crosslinker).

Green vortex-assisted emulsification microextraction using a ternary deep eutectic solvent for extraction of tetracyclines in infant formulas.

A novel green alternative vortex-assisted emulsification liquid-liquid microextraction based on a new hydrophobic deep eutectic solvent (DES) was developed to extract tetracyclines in infant formulas. Five new ternary DESs were synthesized and tested in this regard. Among them [thymol]:[ethylene glycol]:[benzyl alcohol] (2:2:1) DES demonstrated the highest extraction efficiency.

A green alternative QuEChERS developed based on green deep eutectic solvents coupled with gas chromatography-mass spectrometry for the analysis of pesticides in tea samples.

A novel green modified QuEChERS based on green deep eutectic solvents (DES) followed by GC-MS was developed to analyze pesticides in tea samples. Among different tested DESs for the extraction of analytes, ChCl:PEG (1:4) DES showed the highest efficiency. Three-dimensional magnetic graphene was functionalized by ChCl:urea (1:2) natural DES, characterized and used as sorbent in the in-syringe dispersive micro-SPE to cleanup tea extract.

Natural thymol-based ternary deep eutectic solvents: Application in air-bubble assisted-dispersive liquid-liquid microextraction for the analysis of tetracyclines in water.

Four new thymol-based ternary deep eutectic solvents were prepared and evaluated as the extractive phase in air-bubbles assisted dispersive liquid-liquid microextraction for extraction of tetracycline, doxycycline, and oxytetracycline from the water before high-performance liquid chromatography. The maximum extraction efficiencies were obtained using 400 μL of [choline chloride]:[thymol]:[nonanoic acid] in the molar ratio of 1:2:2 at pH = 5. The solvent was characterized by FTIR and NMR spectroscopy.

Deep eutectic solvent-based clean-up/vortex-assisted emulsification liquid-liquid microextraction: Application for multi-residue analysis of 16 pesticides in olive oils.

A new hydrophobic deep eutectic solvent (DES) composed of thymol and vanillin (1:1) was prepared and used as the extraction solvent in vortex-assisted emulsification liquid-liquid microextraction of 16 pesticides in olive oil before GC-μECD analysis. Due to the complexity of oil samples, a DES-based liquid-liquid solvent system (n-hexane/acetonitrile/DES) was developed to achieve an effective clean-up. Among the four examined hydrophilic DESs, [choline chloride]:[urea] led to improved sensitivity, and clean chromatograms with low noise and drift from the sample matrix.

Sleep-Wake Cycle in Young and Older Mice.

Sleep plays a key role in multiple cognitive functions and sleep pattern changes with aging. Human studies revealed that aging decreases sleep efficiency and reduces the total sleep time, the time spent in slow-wave sleep (SWS), and the delta power (1-4 Hz) during sleep; however, some studies of sleep and aging in mice reported opposing results. The aim of our work is to estimate how features of sleep-wake state in mice during aging could correspond to age-dependent changes observed in human.

Slow wave detection in sleeping mice: Comparison of traditional and machine learning methods.

Background: During slow-wave sleep the electroencephalographic (EEG) and local field potential (LFP) recordings reveal the presence of large amplitude slow waves. Systematic extraction of individual slow waves is not trivial.

New Method: In this study, we used the neural network pattern recognition to detect individual slow waves in LFP recorded from mice as well as other commonly used methods that are based on fast frequencies modulation, amplitude, or duration.

UV-Vis, FTIR, H, C NMR spectra and thermal studies of charge transfer complexes formed in the reaction of Gliclazide with π- and σ-electron acceptors.

Charge transfer interactions (CT) between a gliclazide (GLC) donor and a picric acid (PA) π acceptor or iodine σ acceptor, were studied in a chloroform solution and in the solid state. UV-vis spectroscopy elucidated the formation of the complexes, and allowed determination of the stoichiometry, stability constants (K), and thermodynamic quantities (ΔG°, ΔH°, and ΔS°), and spectroscopic properties such as the molar extinction coefficient (ε), oscillator strength (f), transition dipole moment (μ), and ionization potential (I). Beer's law was obeyed over the 2-8 and 4-12 μg mL concentration ranges for GLC with PA (method A) and I (method B), respectively, with correlation coefficients of 0.

Cellular and neurochemical basis of sleep stages in the thalamocortical network.

The link between the combined action of neuromodulators in the brain and global brain states remains a mystery. In this study, using biophysically realistic models of the thalamocortical network, we identified the critical intrinsic and synaptic mechanisms, associated with the putative action of acetylcholine (ACh), GABA and monoamines, which lead to transitions between primary brain vigilance states (waking, non-rapid eye movement sleep [NREM] and REM sleep) within an ultradian cycle. Using ECoG recordings from humans and LFP recordings from cats and mice, we found that during NREM sleep the power of spindle and delta oscillations is negatively correlated in humans and positively correlated in animal recordings.

In vivo models of cortical acquired epilepsy.

The neocortex is the site of origin of several forms of acquired epilepsy. Here we provide a brief review of experimental models that were recently developed to study neocortical epileptogenesis as well as some major results obtained with these methods. Most of neocortical seizures appear to be nocturnal and it is known that neuronal activities reveal high levels of synchrony during slow-wave sleep.

Neocortical focus: experimental view.

All brain normal or pathological activities occur in one of the states of vigilance: wake, slow-wave sleep, or REM sleep. Neocortical seizures preferentially occur during slow-wave sleep. We provide a description of neuronal behavior and mechanisms mediating such a behavior within neocortex taking place in natural states of vigilance as well as during seizures pointing to similarities and differences exhibited during sleep and seizures.

Involvement of the dorsal hippocampal GABA-A receptors in histamine-induced facilitation of memory in the Morris water maze.

Several types of learning and memory processes are regulated by the hippocampus which is an important subcortical structure in the mammalians' brain. Previous investigations have shown that different receptor systems in the CA1 region of hippocampus are involved in learning and memory functions. Investigating the possible influence of dorsal hippocampal GABA-A receptors on histamine-induced spatial facilitation in adult male Wistar rats was the focus of the current study.