High-throughput surface plasmon resonance (SPR) biosensor for rapid and parallelized detection of nucleic acids identifying specific bacterial pathogens is reported. The biosensor consists of a high-performance SPR imaging sensor with polarization contrast and internal referencing (refractive index resolution 2 x 10(-7) RIU) and an array of DNA probes microspotted on the surface of the SPR sensor. It is demonstrated that short sequences of nucleic acids (20-23 bases) characteristic for bacterial pathogens such as Brucella abortus, Escherichia coli, and Staphylococcus aureus can be detected at 100 pM levels. Detection of specific DNA or RNA sequences can be performed in less than 15 min by the reported SPR sensor.

• MeSH
• Bacteria, Aerobic genetics   isolation & purification   MeSH
• Food Analysis methods   MeSH
• Equipment Failure Analysis MeSH
• Biosensing Techniques methods   instrumentation   MeSH
• Equipment Design MeSH
• DNA, Bacterial analysis   genetics   MeSH
• Financing, Organized MeSH
• Food Contamination analysis   MeSH
• Food Microbiology MeSH
• Surface Plasmon Resonance methods   instrumentation   MeSH
• Reproducibility of Results MeSH
• Oligonucleotide Array Sequence Analysis instrumentation   MeSH
• Sensitivity and Specificity MeSH
• Publication type
• Evaluation Study MeSH

• MeSH
• Financing, Organized MeSH
• Publication type
• Abstracts MeSH

Flubendazole, methyl ester of [5-(4-fluorobenzoyl)-1H-benzimidazol-2-yl]carbamic acid, belongs to the group of benzimidazole anthelmintics, which are widely used in veterinary and human medicine. The phase I flubendazole biotransformation includes a hydrolysis of the carbamoyl methyl moiety accompanied by a decarboxylation (hydrolysed flubendazole) and a carbonyl reduction of flubendazole (reduced flubendazole). Flubendazole is a prochiral drug, hence a racemic mixture is formed during non-stereoselective reductions at the carbonyl group. Two bioanalytical HPLC methods were developed and validated for the determination of flubendazole and its metabolites in pig and pheasant hepatic microsomal and cytosolic fractions. Analytes were extracted from biomatrices into tert-butylmethyl ether. The first, achiral method employed a 250 mm x 4 mm column with octylsilyl silica gel (5 microm) and an isocratic mobile phase acetonitrile-0.025 M KH(2)PO(4) buffer pH 3 (28:72, v/v). Albendazole was used as an internal standard. The whole analysis lasted 27 min at a flow rate of 1 ml/min. The second, chiral HPLC method, was performed on a Chiralcel OD-R 250 mm x 4.6 mm column with a mobile phase acetonitrile-1 M NaClO(4) (4:6, v/v). This method enabled the separation of both reduced flubendazole enantiomers. The enantiomer excess was evaluated. The column effluent was monitored using a photodiode-array detector (scan or single wavelength at lambda=246 nm). Each of the analytes under study had characteristic UV spectrum, in addition, their chemical structures were confirmed by high-performance liquid chromatography-mass spectrometry (HPLC-MS) experiments. Stereospecificity in the enzymatic carbonyl reduction of flubendazole was observed. While synthetic racemic mixture of reduced flubendazole was separated to equimolar amounts of both enantiomers, practically only one enantiomer was detected in the extracts from all incubates.

• MeSH
• Anthelmintics analysis   MeSH
• Financing, Organized MeSH
• Spectrometry, Mass, Electrospray Ionization methods   MeSH
• Calibration MeSH
• Mebendazole analogs & derivatives   analysis   MeSH
• Swine MeSH
• Birds MeSH
• Spectrophotometry, Ultraviolet methods   MeSH
• Stereoisomerism MeSH
• Tandem Mass Spectrometry methods   MeSH
• Chromatography, High Pressure Liquid methods   MeSH
• Animals MeSH
• Check Tag
• Animals MeSH
• Publication type
• Validation Study MeSH

Aberrant glycosylation of glycoproteins has been linked with various pathologies. Therefore, understanding the relationship between aberrant glycosylation patterns and the onset and progression of the disease is an important research goal that may provide insights into cancer diagnosis and new therapy development. In this study, we use a surface plasmon resonance imaging biosensor and a lectin array to investigate aberrant glycosylation patterns associated with oncohematological disease-myelodysplastic syndromes (MDS). In particular, we detected the interaction between the lectins and glycoproteins present in the blood plasma of patients (three MDS subgroups with different risks of progression to acute myeloid leukemia (AML) and AML patients) and healthy controls. The interaction with lectins from Aleuria aurantia (AAL) and Erythrina cristagalli was more pronounced for plasma samples of the MDS and AML patients, and there was a significant difference between the sensor response to the interaction of AAL with blood plasma from low and medium-risk MDS patients and healthy controls. Our data also suggest that progression from MDS to AML is accompanied by sialylation of glycoproteins and increased levels of truncated O-glycans and that the number of lectins that allow discriminating different stages of disease increases as the disease progresses.

• MeSH
• Leukemia, Myeloid, Acute * MeSH
• Biosensing Techniques * MeSH
• Glycoproteins metabolism   MeSH
• Glycosylation MeSH
• Plasma metabolism   MeSH
• Lectins MeSH
• Humans MeSH
• Myelodysplastic Syndromes * therapy   MeSH
• Check Tag
• Humans MeSH
• Publication type
• Journal Article MeSH
• Research Support, Non-U.S. Gov't 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.

• 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

• Conspectus
• Biotechnologie. Genetické inženýrství
• NML Fields
• biomedicínské inženýrství

We designed a simple, portable, low-cost and low-weight nondispersive infrared (NDIR) spectroscopy-based system for continuous remote sensing of atmospheric methane (CH4) with rapidly pulsed near-infrared light emitting diodes (NIR LED) at 1.65 μm. The use of a microcontroller with a field programmable gate array (μC-FPGA) enables on-the-fly and wireless streaming and processing of large data streams (~2 Gbit/s). The investigated NIR LED detection system offers favourable limits of detection (LOD) of 300 ppm (±5%) CH4,. All the generated raw data were processed automatically on-the-fly in the μC-FPGA and transferred wirelessly via a network connection. The sensing device was deployed for the portable sensing of atmospheric CH4 at a local landfill, resulting in quantified concentrations within the sampling area (ca 400 m2) in the range of 0.5%-3.35% CH4. This NIR LED-based sensor system offers a simple low-cost solution for continuous real-time, quantitative, and direct measurement of CH4 concentrations in indoor and outdoor environments, yet with the flexibility provided by the custom programmable software. It possesses future potential for remote monitoring of gases directly from mobile platforms such as smartphones and unmanned aerial vehicles (UAV).

• Publication type
• Journal Article MeSH

Multiway array decomposition methods have been shown to be promising statistical tools for identifying neural activity in the EEG spectrum. They blindly decompose the EEG spectrum into spatial-temporal-spectral patterns by taking into account inherent relationships among signals acquired at different frequencies and sensors. Our study evaluates the stability of spatial-temporal-spectral patterns derived by one particular method, parallel factor analysis (PARAFAC). We focused on patterns' stability over time and in population and divided the complete data set containing data from 50 healthy subjects into several subsets. Our results suggest that the patterns are highly stable in time, as well as among different subgroups of subjects. Further, we show with simultaneously acquired fMRI data that power fluctuations of some patterns have stable correspondence to hemodynamic fluctuations in large-scale brain networks. We did not find such correspondence for power fluctuations in standard frequency bands, the common way of dealing with EEG data. Altogether, our results suggest that PARAFAC is a suitable method for research in the field of large-scale brain networks and their manifestation in EEG signal.

• MeSH
• Acoustic Stimulation MeSH
• Adult MeSH
• Electroencephalography * MeSH
• Factor Analysis, Statistical MeSH
• Oxygen blood   MeSH
• Humans MeSH
• Magnetic Resonance Imaging MeSH
• Brain Mapping MeSH
• Young Adult MeSH
• Brain diagnostic imaging   physiology   MeSH
• Brain Waves physiology   MeSH
• Neural Pathways diagnostic imaging   physiology   MeSH
• Image Processing, Computer-Assisted * MeSH
• Photic Stimulation MeSH
• Animals MeSH
• Check Tag
• Adult MeSH
• Humans MeSH
• Young Adult MeSH
• Male MeSH
• Female MeSH
• Animals MeSH
• Publication type
• Journal Article MeSH
• Research Support, Non-U.S. Gov't MeSH

Capillary electrophoresis (CE) with contactless conductivity detection (C(4)D) is readily applicable to determinations of amino acids in clinical samples. Most of these analyses employ long separation pathways. This chapter describes CE/C(4)D determinations of 28 biogenic amino acids in a short capillary with an effective length of 18 cm. All the test amino acids can be mutually separated in electrolytes of 0.5-10 mol/L acetic acid. The time of analysis does not exceed 6 min; the limits of detection vary from 0.1 to 1.7 μmol/L for all the analytes. The pretreatment of the biological material is very simple, consisting of the removal of proteins by an addition of acetonitrile and subsequent filtration. The procedure has been successfully applied to determinations of the whole amino acid spectra in blood plasma, urine, saliva, cerebrospinal, and amniotic fluid samples.

• MeSH
• Amino Acids analysis   blood   urine   MeSH
• Electric Conductivity * MeSH
• Electrophoresis, Capillary methods   MeSH
• Calibration MeSH
• Chemistry, Clinical methods   MeSH
• Humans MeSH
• Amniotic Fluid metabolism   MeSH
• Solutions MeSH
• Saliva metabolism   MeSH
• Check Tag
• Humans MeSH
• Publication type
• Journal Article MeSH
• Research Support, Non-U.S. Gov't MeSH

Refractometric sensors utilizing surface plasmon resonance (SPR) should satisfy a series of performance metrics, bulk sensitivity, thin-film sensitivity, refractive-index resolution, and high-Q-factor resonance, as well as practical requirements such as manufacturability and the ability to separate optical and fluidic paths via reflection-mode sensing. While many geometries such as nanohole, nanoslit, and nanoparticles have been employed, it is nontrivial to engineer nanostructures to satisfy all of the aforementioned requirements. We combine gold nanohole arrays with a water-index-matched Cytop film to demonstrate reflection-mode, high-Q-factor (Qexp = 143) symmetric plasmonic sensor architecture. Using template stripping with a Cytop film, we can replicate a large number of index-symmetric nanohole arrays, which support sharp plasmonic resonances that can be probed by light reflected from their backside with a high extinction amplitude. The reflection geometry separates the optical and microfluidic paths without sacrificing sensor performance as is the case of standard (index-asymmetric) nanohole arrays. Furthermore, plasmon hybridization caused by the array refractive-index symmetry enables dual-mode detection that allows distinction of refractive-index changes occurring at different distances from the surface, making it possible to identify SPR response from differently sized particles or to distinguish binding events near the surface from bulk index changes. Due to the unique combination of a dual-mode reflection-configuration sensing, high-Q plasmonic modes, and template-stripping nanofabrication, this platform can extend the utility of nanohole SPR for sensing applications involving biomolecules, polymers, nanovesicles, and biomembranes.

• MeSH
• Biosensing Techniques methods   MeSH
• Phosphatidylcholines chemistry   MeSH
• Limit of Detection MeSH
• Liposomes analysis   chemistry   MeSH
• Nanopores * MeSH
• Aluminum Oxide chemistry   MeSH
• Surface Plasmon Resonance methods   MeSH
• Serum Albumin, Bovine analysis   MeSH
• Cattle MeSH
• Gold chemistry   MeSH
• Animals MeSH
• Check Tag
• Cattle MeSH
• Animals MeSH
• Publication type
• Journal Article MeSH
• Research Support, Non-U.S. Gov't MeSH
• Research Support, U.S. Gov't, Non-P.H.S. MeSH