One of the most widely investigated functions of the brain is vision. Whereas special attention is often paid to motion detection and its modulation by attention, comparatively still little is known about the structural background of this function. We therefore, examined the white matter microstructural background of coherent motion detection. A random-dot kinematogram paradigm was used to measure the sensitivity of healthy individuals׳ to movement coherence. The potential correlation was investigated between the motion detection threshold and the white matter microstructure as measured by high angular resolution diffusion MRI. The Track Based Spatial Statistics method was used to address this correlation and probabilistic tractography to reveal the connection between identified regions. A significant positive correlation was found between the behavioural data and the local fractional anisotropy in the posterior part of the right superior frontal gyrus, the right juxta-cortical superior parietal lobule, the left parietal white matter, the left superior temporal gyrus and the left optic radiation. Probabilistic tractography identified pathways that are highly similar to the segregated attention networks, which have a crucial role in the paradigm. This study draws attention to the structural determinant of a behavioural function.

• Keywords
• DTI, MRI, Motion detection, Vision, White matter microstructure,
• MeSH
• Anisotropy MeSH
• White Matter anatomy & histology   physiology   MeSH
• Differential Threshold physiology   MeSH
• Diffusion Magnetic Resonance Imaging MeSH
• Adult MeSH
• Humans MeSH
• Young Adult MeSH
• Brain anatomy & histology   physiology   MeSH
• Neural Pathways anatomy & histology   physiology   MeSH
• Psychophysics MeSH
• Photic Stimulation MeSH
• Signal Detection, Psychological physiology   MeSH
• Motion Perception physiology   MeSH
• Check Tag
• Adult MeSH
• Humans MeSH
• Young Adult MeSH
• Male MeSH
• Female MeSH
• Publication type
• Journal Article MeSH
• Research Support, Non-U.S. Gov't MeSH

Capillary electrophoresis with capacitively coupled contactless conductivity detection (CE-C4D) was employed for fast determination of meldonium (MEL) in urine samples. Background electrolyte consisting of 2M acetic acid (pH 2.3) was used for separation of MEL from cationic compounds present in urine samples and the overall analysis time was less than 4min per sample. Direct injection of urine samples was possible after 1:9 dilution with deionized water. This simple sample pretreatment was sufficient to eliminate possible matrix effects on CE performance and allowed for precise and sensitive determination of free MEL in urine. Excellent linearity (r2≥0.9998) was obtained for two concentration ranges, 0.02-4μgmL-1 and 2-200μgmL-1, by simply changing injection time from 10 to 2s without the need for additional dilution of urine samples. Limit of detection was 0.015μgmL-1 and average recoveries from urine samples spiked at 0.02-123.5μgmL-1 MEL ranged from 97.6-99.9%. Repeatability of migration times and peak areas was better than 0.35% and 4.2% for intraday and 0.95% and 4.7% for interday measurements, respectively. The above reported data proved good applicability of the CE-C4D method to determination of various MEL concentrations in urine samples and good long-term performance of the analytical system. The method might be particularly useful in analyses of large batches of samples for initial testing of MEL-positive vs. MEL-negative urine samples.

• Keywords
• Capillary electrophoresis, Contactless conductivity detection, Meldonium, Mildronate, Urine,
• MeSH
• Doping in Sports MeSH
• Electric Conductivity MeSH
• Electrophoresis, Capillary methods   MeSH
• Electrolytes MeSH
• Humans MeSH
• Methylhydrazines urine   MeSH
• Substance Abuse Detection methods   MeSH
• Water MeSH
• Check Tag
• Humans MeSH
• Publication type
• Journal Article MeSH
• Names of Substances
• 3-(2,2,2-trimethylhydrazine)propionate MeSH Browser
• Electrolytes MeSH
• Methylhydrazines MeSH
• Water MeSH

Water, ubiquitous in analytical methods, is renowned for its fluorescence quenching properties, influencing techniques like fluorescence spectrophotometry or techniques with fluorescence detection. This study explores the impact of water (H₂O) substitution for heavy water (D₂O) on the fluorescence behavior of anthraquinones and anthracyclines. Anthraquinones and anthracyclines play crucial roles in pharmacy, serving as essential components in various therapeutic formulations, particularly in cancer treatment and other pharmacological interventions. Capillary electrophoresis (CE) with heavy water as the background electrolyte (BGE) solvent offers superior sensitivity to the separation and detection of these analytes. Experimental results demonstrate the improved detection limits and separation efficiency of selected anthraquinones rhein (RH), aloe-emodin (AE), and anthracyclines doxorubicin (DOX), epirubicin (EPI) and daunorubicine (DAU) in heavy water-based buffers, highlighting the potential of heavy water in advancing analytical chemistry.

• Keywords
• Anthracyclines, Anthraquinones, Capillary electrophoresis, Fluorescence detection, Heavy water,
• MeSH
• Anthraquinones * chemistry   analysis   MeSH
• Anthracyclines analysis   chemistry   MeSH
• Electrophoresis, Capillary * methods   MeSH
• Spectrometry, Fluorescence * methods   MeSH
• Limit of Detection MeSH
• Deuterium Oxide chemistry   MeSH
• Water chemistry   MeSH
• Publication type
• Journal Article MeSH
• Names of Substances
• Anthraquinones * MeSH
• Anthracyclines MeSH
• Deuterium Oxide MeSH
• rhein MeSH Browser
• Water MeSH

The new screening method for rapid evaluation of major phenolic compounds in apples has been developed. Suitability of coupling HPLC/UHPLC separation with the diode-array detection and universal charged aerosol detection with respect to the presence of interfering substances was tested. Characteristics of both detection techniques were compared and method linearity, limits of detection and quantitation, and selectivity of them determined. Student t-test based on slopes of calibration plots was applied for the detailed comparison. The diode-array detection provided the best results regarding sensitivity and selectivity of the developed method in terms of evaluation of phenolics profiles. The response of the charged aerosol detector was negatively affected by co-eluting substances during rapid-screening analyses. Coulometric detection was used for advanced characterization of extracts in terms of antioxidant content and strength to obtain more complex information concerning sample composition. This detection also allowed evaluation of unidentified compounds with antioxidant activity. HPLC/UHPLC separation using a combination of diode-array and coulometric detectors thus represented the best approach enabling quick, yet complex characterization of bioactive compounds in apples.

• Keywords
• antioxidants, apple extracts, charged aerosol detection, complex matrices, coulometric detection, detection sensitivity, diode-array detection, phenolic compounds,
• MeSH
• Aerosols chemistry   MeSH
• Antioxidants chemistry   MeSH
• Chromatography methods   MeSH
• Electrochemistry methods   MeSH
• Phenol chemistry   MeSH
• Phenols analysis   MeSH
• Calibration MeSH
• Limit of Detection MeSH
• Malus metabolism   MeSH
• Food Technology MeSH
• Reproducibility of Results MeSH
• Chromatography, High Pressure Liquid methods   MeSH
• Publication type
• Journal Article MeSH
• Names of Substances
• Aerosols MeSH
• Antioxidants MeSH
• Phenol MeSH
• Phenols MeSH

To ensure food safety and to prevent unnecessary foodborne complications this study reports fast, fully automated process for histamine determination. This method is based on magnetic separation of histamine with magnetic particles and quantification by the fluorescence intensity change of MSA modified CdSe Quantum dots. Formation of Fe2O3 particles was followed by adsorption of TiO2 on their surface. Magnetism of developed probe enabled rapid histamine isolation prior to its fluorescence detection. Quantum dots (QDs) of approx. 3 nm were prepared via facile UV irradiation. The fluorescence intensity of CdSe QDs was enhanced upon mixing with magnetically separated histamine, in concentration-dependent manner, with a detection limit of 1.6 μM. The linear calibration curve ranged between 0.07 and 4.5 mM histamine with a low LOD and LOQ of 1.6 μM and 6 μM. The detection efficiency of the method was confirmed by ion exchange chromatography. Moreover, the specificity of the sensor was evaluated and no cross-reactivity from nontarget analytes was observed. This method was successfully applied for the direct analysis of histamine in white wine providing detection limit much lower than the histamine maximum levels established by EU regulation in food samples. The recovery rate was excellent, ranging from 84 to 100% with an RSD of less than 4.0%. The main advantage of the proposed method is full automation of the analytical procedure that reduces the time and cost of the analysis, solvent consumption and sample manipulation, enabling routine analysis of large numbers of samples for histamine and highly accurate and precise results.

• Keywords
• Food safety, Histamine, Ion exchange chromatography, Maghemite, Quantum dots,
• MeSH
• Fluorescence MeSH
• Fluorescent Dyes chemistry   MeSH
• Spectrometry, Fluorescence methods   MeSH
• Histamine analysis   MeSH
• Food Contamination analysis   MeSH
• Metal Nanoparticles chemistry   MeSH
• Quantum Dots chemistry   MeSH
• Limit of Detection MeSH
• Magnetic Phenomena MeSH
• Silanes chemistry   MeSH
• Cadmium Compounds chemistry   MeSH
• Tellurium chemistry   MeSH
• Titanium chemistry   MeSH
• Wine analysis   MeSH
• Ferric Compounds chemistry   MeSH
• Publication type
• Journal Article MeSH
• Names of Substances
• cadmium telluride MeSH Browser
• ferric oxide MeSH Browser
• Fluorescent Dyes MeSH
• Histamine MeSH
• Silanes MeSH
• Cadmium Compounds MeSH
• Tellurium MeSH
• tetraethoxysilane MeSH Browser
• Titanium MeSH
• titanium dioxide MeSH Browser
• Ferric Compounds MeSH

We present a compact surface plasmon resonance (SPR) biosensor for the detection of bisphenol A (BpA), an endocrine-disrupting chemical. The biosensor is based on an SPR sensor platform (SPRCD) and the binding inhibition detection format. The detection of BpA in PBS and wastewater was performed at concentrations ranging from 0.05 to 1,000 ng/ml. The limit of detection for BpA in PBS and wastewater was estimated to be 0.08 and 0.14 ng/ml, respectively. It was also demonstrated that the biosensor can be regenerated for repeated use. Results achieved with the SPR biosensor are compared with those obtained using ELISA and HPLC methods.

• MeSH
• Benzhydryl Compounds MeSH
• Biosensing Techniques methods   MeSH
• Water Pollutants, Chemical analysis   chemistry   MeSH
• Phenols analysis   chemistry   MeSH
• Limit of Detection MeSH
• Surface Plasmon Resonance methods   MeSH
• Publication type
• Journal Article MeSH
• Research Support, Non-U.S. Gov't MeSH
• Names of Substances
• Benzhydryl Compounds MeSH
• bisphenol A MeSH Browser
• Water Pollutants, Chemical MeSH
• Phenols MeSH

In this study, we developed a novel and environmentally friendly method for the determination of selected cannabinoids - cannabidiol, cannabinol, tetrahydrocannabinol, JWH 073 synthetic cannabinoid, hexahydrocannabinol (HHC), and hexahydrocannabinol-O-acetate - using high-performance liquid chromatography with electrochemical detection. The method employs a boron-doped diamond working electrode, which offers significant advantages in comparison with commonly used materials. Its main strengths include low background currents, reduced fouling, and an extended potential window, making it suitable for detecting compounds that are not readily oxidizable. The chromatographic system utilized a reversed-phase Gemini C18 column with a mobile phase consisting of acetonitrile and 25 mM phosphate buffer (pH 4.4) in step-gradient mode from 68 % to 88 % acetonitrile. The separation and determination of cannabinoids were optimized to be completed in less than 25 min. Hydrodynamic voltammetry was performed to identify the optimal potential for the amperometric detection, with a working potential of + 1400 mV (vs. Pd/H₂) providing the best analytical response based on S/N ratio. Under these optimal separation and detection conditions, the limits of detection were within the range of 6.1-666 nM (for cannabidiol and 9(R)-hexahydrocannabinol-O-acetate), while the response was linear within the concentration range measured up to 10 μM. The method demonstrated good linearity, precision, and sensitivity, with limits of detection and quantitation reaching nanomolar levels. The developed method was successfully applied to commercial samples of HHC jelly bears and HHC distillate.

• Keywords
• Boron doped diamond, CBD, Cannabinoids, Electrochemical detection, HHC, HPLC, THC,
• MeSH
• Boron * chemistry   MeSH
• Diamond * chemistry   MeSH
• Electrochemical Techniques * methods   MeSH
• Electrodes MeSH
• Cannabinoids * analysis   chemistry   isolation & purification   MeSH
• Limit of Detection MeSH
• Reproducibility of Results MeSH
• Chromatography, High Pressure Liquid methods   MeSH
• Publication type
• Journal Article MeSH
• Names of Substances
• Boron * MeSH
• Diamond * MeSH
• Cannabinoids * MeSH

We report here on the development of tailored plasmonic AgNPs/C:H:N:O plasma polymer nanocomposites for the detection of the pathogenic bacterium Borrelia afzelii , with high selectivity and sensitivity. Silver (Ag) nanoparticles, generated by a gas aggregation source, are incorporated onto a C:H:N:O plasma polymer matrix, which is deposited by magnetron sputtering of a nylon 6.6. These anchored Ag nanoparticles propagate localized surface plasmon resonance (LSPR), optically responding to changes caused by immobilized pathogens near the nanoparticles. The tailored functionalization of AgNPs/C:H:N:O nanocomposite surface allows both high selectivity for the pathogen and high sensitivity with an LSPR red-shift Δλ > (4.20 ± 0.71) nm for 50 Borrelia per area 0.785 cm2. The results confirmed the ability of LSPR modulation for the rapid and early detection of (not only) tested pathogens.

• Keywords
• C:H:N:O thin film, Lyme disease, ag nanoparticles, borrelia, localized surface plasmon resonance, magnetron sputtering, nanocomposite, nylon, plasma polymer, surface functionalization,
• MeSH
• Metal Nanoparticles * chemistry   MeSH
• Limit of Detection * MeSH
• Nanocomposites * chemistry   MeSH
• Surface Plasmon Resonance * methods   MeSH
• Silver * chemistry   MeSH
• Publication type
• Journal Article MeSH
• Names of Substances
• Silver * MeSH

A new HPLC method was developed and validated for the determination of asymmetric and symmetric dimethylarginines and l-arginine in human plasma. After SPE and evaporation of the eluate, the samples were derivatised with an o-phthaldialdehyde reagent containing 3-mercaptopropionic acid. The derivatives formed were analysed by isocratic RP-HPLC with electrochemical detection at +320 mV. The mobile phase consisted of 50 mM phosphate buffer (pH 6.1) containing 10% v/v acetonitrile, the flow rate was 1 mL/min. The retention times of all compounds including monomethylarginine (internal standard) were <24 min. The LODs (S/N 3:1) were 0.012 μM for both dimethylarginines and 0.013 μM for L-arginine; the linearity of the method was from 0.1 to 20 μM for both dimethylarginines and from 1 to 200 μM for L-arginine. Absolute extraction recoveries measured for all analytes ranged from 85 to 88%.

• Keywords
• Arginine, Asymmetric dimethylarginine, Electrochemical detection, HPLC, Symmetric dimethylarginine,
• MeSH
• Arginine analogs & derivatives   blood   MeSH
• Blood Chemical Analysis instrumentation   methods   MeSH
• Electrochemical Techniques * MeSH
• Humans MeSH
• Limit of Detection MeSH
• Reference Standards MeSH
• Chromatography, High Pressure Liquid * MeSH
• Check Tag
• Humans MeSH
• Publication type
• Journal Article MeSH
• Research Support, Non-U.S. Gov't MeSH
• Validation Study MeSH
• Names of Substances
• Arginine MeSH
• dimethylarginine MeSH Browser

Diabetes mellitus represents one of the most widespread diseases in civilization nowadays. Since the costs for treating and diagnosing of diabetes represent several billions of dollars per year, a cheap, fast, and simple sensor for diabetes diagnosis is needed. Electrochemical insulin sensors can be considered as a novel approach for diabetes diagnosis. In this study, carbon electrode with electrodeposited NiO nanoparticles was selected as a suitable electrode material for insulin determination. The morphology and surface composition were studied by scanning electron microscopy (SEM), energy dispersive X-ray (EDX) spectroscopy, and X-ray photoelectron spectroscopy (XPS). For a better understanding of insulin determination on NiO-modified electrodes, the mechanism of electrochemical reaction and the kinetic parameters were studied. They were calculated from both voltammetric and amperometric measurements. The modified carbon electrode displayed a wide linear range from 600 nM to 10 µM, a low limit of detection of 19.6 nM, and a high sensitivity of 7.06 µA/µM. The electrodes were stable for 30 cycles and were able to detect insulin even in bovine blood serum. Additionally, the temperature stability of this electrode and its storage conditions were studied with appropriate outcomes. The above results show the high promise of this electrode for detecting insulin in clinical samples.

• Keywords
• NiO nanoparticles, electrochemical sensor, insulin,
• MeSH
• Electrochemical Techniques * MeSH
• Electrodes MeSH
• Insulin MeSH
• Humans MeSH
• Limit of Detection MeSH
• Nanoparticles * MeSH
• Nickel MeSH
• Cattle MeSH
• Animals MeSH
• Check Tag
• Humans MeSH
• Cattle MeSH
• Animals MeSH
• Publication type
• Journal Article MeSH
• Names of Substances
• Insulin MeSH
• Nickel MeSH