The Infona portal uses cookies, i.e. strings of text saved by a browser on the user's device. The portal can access those files and use them to remember the user's data, such as their chosen settings (screen view, interface language, etc.), or their login data. By using the Infona portal the user accepts automatic saving and using this information for portal operation purposes. More information on the subject can be found in the Privacy Policy and Terms of Service. By closing this window the user confirms that they have read the information on cookie usage, and they accept the privacy policy and the way cookies are used by the portal. You can change the cookie settings in your browser.
A new, sensitive, and accurate on-line spectrophotometric method for the determination of palladium was developed. The method is based on the reaction between Pd(II) and 2,2′-furyldioxime in nitric acid medium. The absorbance of the complex is spectrophotometrically measured at 410nm with a diode-array detector. Several factors that influence the analytical performance of the method such as acidity,...
Lubricating oils are crucial in the operation of automotive engines because they both reduce friction between moving parts and protect against corrosion. However, the performance of lubricant oil may be affected by contaminants, such as gasoline, diesel, ethanol, water and ethylene glycol. Although there are many standard methods and studies related to the quantification of contaminants in lubricant...
This paper describes the use of a commercially available thin-layer flow through a detector with the sensing block customized in an original design for acetylcholinesterase (AChE) immobilization and suitable for inhibition studies by flow injection analysis (FI). AChE was chemically linked onto a gold disk substrate adjacent to a silver disk electrode. The downstream positioned silver electrode, poised...
Hyperspectral imaging was exploited for its potential in direct and fast determination of Pseudomonas loads in raw chicken breast fillets. A line-scan hyperspectral imaging system (900–1700nm) was employed to obtain sample images, which were then further corrected, modified and processed. The prepared images were correlated with the true Pseudomonas counts of these samples using partial least squares...
In this paper, linear and cyclic tetrapeptide bonded stationary phases, were synthesized by the solid-phase synthesis method. Each amino acid coupling step was monitored by the ninhydrin test using UV/visible spectrophotometry. The proposed materials were characterized by UV spectroscopy, Fourier transform infrared spectroscopy, elemental analysis and thermogravimetric analysis, which proved the successful...
An optical immunosensor was developed and validated on the surface of microparticles for the determination of a biopharmaceutical protein. The recombinant human myelin basic protein (rhMBP) was produced in milk of transgenic cows as a His-tagged fusion protein. Previous work indicated exclusive association of rhMBP with milk casein micelles that hindered direct determination of the protein in milk...
A new electrochemical biosensor with enhanced sensitivity was developed for detection of cholesterol by using platinum–palladium–chitosan–graphene hybrid nanocomposites (PtPd–CS–GS) functionalized glassy carbon electrode (GCE). An electrodeposition method was applied to form PtPd nanoparticles-doped chitosan–graphene hybrid nanocomposites (PtPd–CS–GS), which were characterized by scanning electron...
A method for the determination of perfluorocarboxylic acids (PFCAs) and perfluorooctanesulfonic acid (PFOS) in sewage sludge based on focused ultrasound solid–liquid extraction (FUSLE) and reverse-phase ultra-performance liquid chromatography (UPLC) coupled to quadrupole-time of flight mass spectrometry (QTOFMS) has been developed. FUSLE is a fast, low-cost and efficient extraction technique based...
We report a simple and sensitive method for label-free detection of single-stranded DNA-binding protein (SSBP) based on an array of microfabricated cantilevers. The single-stranded DNA (ssDNA) was immobilized on the surface of the sensing cantilevers to detect SSBP, while the reference cantilevers were modified with 6-mercapto-1-hexanol to detect any unwanted cantilever deflection. The differential...
The rate of reaction of phenolic antioxidants with DPPH depends on solvent composition. The rate constants can differ by more than two orders of magnitude for the same phenolic compound. Reactions are faster in alcohols than in ethyl acetate that is used routinely for the analysis of antioxidant potential (AOP) of nonpolar samples such as vegetable oils. Incorporation of an acid base pair into the...
A sensitive method using a miniature analytical system with a capacitively coupled plasma microtorch (25W, 13.56MHz, 0.4lmin −1 Ar) was developed and evaluated for the determination of As and Sb in recyclable plastics and biodegradable materials by hydride generation optical emission spectrometry. Given their toxicity, As and Sb should be subject to monitoring in such materials despite not...
In this study, a magnetic microsphere-confined graphene (Fe 3 O 4 @SiO 2 -G) was prepared as a novel adsorbent for the preconcentration of some phthalate esters in environmental water and soybean milk samples prior to high performance liquid chromatography analysis. The properties and morphology of the Fe 3 O 4 @SiO 2 -G were characterized by transmission...
In this comparative study, the fabrication and the sensing properties of various reflectometric optical ammonia gas sensors are described. In the first set of experiments the role of the support material was investigated on four different sensor membranes. Two of them were prepared by the adsorption of bromocresol green indicator on anodized aluminum plates. The applied anodizing voltages were 12V...
The literature increasingly reports sampling rates (R s ) for Polar Organic Chemical Integrative Samplers (POCIS) but the data obtained come from various calibration systems that are not always well-defined (agitation, temperature, measured micropollutant concentrations in water,…). In order to obtain accurate laboratory R s for priority and emerging substances, POCIS need to be exposed...
In this study, a two-phase hollow fiber liquid-phase microextraction (HF-LPME) coupling with ultra performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS) method was developed for determination of four non-steroidal anti-inflammatory (NSAIDs)—salicylic acid, ibuprofen, naproxen and diclofenac in real water samples. The influencing parameters of HF-LPME sample preparation method, such...
A simple, sensitive and reproducible ultra-performance liquid chromatography method for determination of ciprofloxacin, difloxacin, lomefloxacin, norfloxacin and ofloxacin oxidation stability under permanganate treatment in acidic conditions at pH from 3.0 to 6.0, was developed. Chromatographic separations were carried out using the Acquity UPLC BEH C 18 column; (2.1×100mm, 1.7μm particle...
A novel interface for on line coupling capillary electrophoresis with hydride generation electrothermal atomic absorption spectrometry (CE–HG–ETAAS) has been developed. The interface performance was examined in detail. The technique could be used to convert arsenic compounds from CE separation to corresponding volatile hydrides determined by HG–ETAAS. This paper aims to explore the best condition...
A highly sensitive and selective multi-walled carbon nanotube (MWCNT)-based multicolor fluorescent nanobeacon is developed for multiplexed analysis of DNA in homogeneous solution. In this work, three different dye-labeled DNA hairpins were adsorbed on MWCNTs surface via π-stacking, which brings the dyes and MWCNTs into close proximity and leads to the quenching of fluorescence of the dyes. When target...
An on-chip immunoassay to detect C-reactive protein (CRP) was performed using a polyester-toner (PT) microchip. CRP is a highly conserved plasma protein responding to inflammation and is used for clinical purposes to diagnose an inflammatory state. For rapid analysis and specific interactions in immunoassays, extensive studies using microfluidic chips have been carried out. Recently, a simple technique...
Set the date range to filter the displayed results. You can set a starting date, ending date or both. You can enter the dates manually or choose them from the calendar.