Hypochlorous Acid - Analytical Methods and Antimicrobial Activity

Hypochlorous acid (HOCl) is produced by the human body’s immune cells to fight infections. It is effective against a broad range of microorganisms. It is non-toxic, non-irritant and non-corrosive at proper usage concentrations. There are some available commercial products that contain HOCl. However, its low storage stability constitutes a major challenge. This review considers the antimicrobial activity of HOCl and its methods of analysis.Keywords: Antimicrobial activity, Hypochlorous acid, Analytical method

Efectos del secado al aire y solar sobre la calidad nutricional del aceite, las semillas y pieles de las uvas Muscat Hamburg

Grape pomace is an agro-industrial by-product from the production of must (grape juice) by pressing whole grapes. In order to evaluate the seeds and skins of the grape pomace, it must first be dried and then separated in a screen machine. The drying of pomace is an important and necessary process for the optimum separation of seeds. The main purpose of this study was to determine the optimum drying process for obtaining high-quality grape seed oil. In this research, open air and solar energy drying methods were compared in terms of water activity, total bacterial and mold-yeast count, along with the chemical and fatty acid compositions of pressed grape residues. Oleic acid and linoleic acid contents ranged from 16.56-16.96% and 71.45-71.96%, respectively. Antioxidant activities ranged from 2.33-2.80 μmol trolox/g. The results showed that the drying methods did not decrease the nutritional quality of grape residues and prevented microbial growth by decreasing water activity to below 0.60.El orujo de uva es un subproducto agroindustrial de la producción de mosto (jugo de uva) al prensar las uvas enteras. Para poder evaluar las semillas y las pieles del orujo de uva, primero debe secarse y luego separarse mediante una máquina de tamizado. El secado del orujo es un proceso importante y necesario para una separación óptima de las semillas. El objetivo principal de este estudio fue determinar el proceso de secado óptimo para obtener aceites de semillas de uva de alta calidad. En este trabajo, los métodos de secado al aire libre y la energía solar de los residuos de uva prensados se compararon en términos de actividad de agua, recuento total de bacterias y moho, así como la composición de ácidos grasos. Los contenidos de ácido oleico y linoleico variaron entre 16,56-16,96% y 71,45-71,96%, respectivamente. Las actividades antioxidantes variaron entre 2,33-2,80 μmol trolox/g. Los resultados mostraron que los métodos de secado no disminuyeron la calidad nutricional de los residuos de la uva y evitaron el crecimiento microbiano al disminuir la actividad del agua por debajo de 0,60

Istodobno spektrofotometrijsko određivanje losartan kalija, amlodipin besilata i hidroklorotiazida u farmaceutskim pripravcima kemometrijskom metodom

In the present work, four different spectrophotometric methods for simultaneous estimation of losartan potassium, amlodipine besilate and hydrochlorothiazide in raw materials and in formulations are described. Overlapped data was quantitatively resolved by using chemometric methods, classical least squares (CLS), multiple linear regression (MLR), principal component regression (PCR) and partial least squares (PLS). Calibrations were constructed using the absorption data matrix corresponding to the concentration data matrix, with measurements in the range of 230.5350.4 nm (∆λ = 0.1 nm) in their zero order spectra. The linearity range was found to be 840, 15 and 315 μg ml1 for losartan potassium, amlodipine besilate and hydrochlorothiazide, respectively. The validity of the proposed methods was successfully assessed for analyses of drugs in the various prepared physical mixtures and in tablet formulations.U radu su opisane četiri spektrofotometrijske metode za istodobno određivanje losartan kalija, amlodipin besilata i hidroklorotiazida u sirovinama i farmaceutskim pripravcima. Podaci koji su se preklapali kvantitativno su razlučeni kemometrijskim metodama, klasičnom metodom najmanjih kvadrata (CLS), multiplom linearnom regresijom (MLR), regresijom glavnih komponenata (PCR) te metodom parcijalnih najmanjih kvadrata (PLS). Kalibracije su provedene koristeći podatke o ovisnosti apsorpcije o koncentracijama, mjereći spektre nultog reda u rasponu 230,5350,4 nm (∆λ = 0,1 nm). Linearnost za losartan kalij bila je 840, za amlodipin besilat 15, a za hidroklorotiazid 315 μg ml1. Valjanost predloženih metoda uspješno je potvrđena analizom navedenih lijekova u različitim pripremljenim smjesama i tabletama

Simultano UV-spektrofotometrijsko određivanje ramiprila, acetilsalicilne kiseline i atorvastatin kalcija u kapsulama primjenom kemometrijskih metoda

In the present work, three different spectrophotometric methods for simultaneous estimation of ramipril, aspirin and atorvastatin calcium in raw materials and in formulations are described. Overlapped data was quantitatively resolved by using chemometric methods, viz. inverse least squares (ILS), principal component regression (PCR) and partial least squares (PLS). Calibrations were constructed using the absorption data matrix corresponding to the concentration data matrix. The linearity range was found to be 1-5, 10-50 and 2-10 µg mL–1 for ramipril, aspirin and atorvastatin calcium, respectively. The absorbance matrix was obtained by measuring the zero-order absorbance in the wavelength range between 210 and 320 nm. A training set design of the concentration data corresponding to the ramipril, aspirin and atorvastatin calcium mixtures was organized statistically to maximize the information content from the spectra and to minimize the error of multivariate calibrations. By applying the respective algorithms for PLS 1, PCR and ILS to the measured spectra of the calibration set, a suitable model was obtained. This model was selected on the basis of RMSECV and RMSEP values. The same was applied to the prediction set and capsule formulation. Mean recoveries of the commercial formulation set together with other figures of merit (calibration sensitivity, selectivity, limit of detection, limit of quantification and analytical sensitivity) were estimated. Validity of the proposed approaches was successfully assessed for analyses of drugs in the various prepared physical mixtures and formulations.U radu su opisane tri različite spektrofotometrijske metode za određivanje ramiprila, acetilsalicilne kiseline i atorvastatin kalcija u sirovinama i formulacijama. Preklapanje podataka kvantitativno je riješeno pomoću kemometrijskih metoda, tj. metodama inverznih najmanjih kvadrata (ILS), regresije glavnog sastojka (PCR) i djelomičnih najmanjih kvadrata (PLS). Kalibracije su postavljene pomoću matrice podataka za apsorpciju koja odgovara matrici pripadajućih koncentracija. Područje linearnosti za ramipril iznosilo je 1–5, za acetilsalicilnu kiselinu 10–50, a za atorvastatin kalcij 2–10 µg mL–1. Matrica s apsorbancijama dobivena je mjerenjem apsorbancije nultog reda na valnim duljinama između 210 i 320 nm. Set podataka za koncentracije ramiprila, acetilsalicilne kiseline i atorvastatin kalcija u smjesi statistički je tako organiziran da osigura maksimalnu količinu informacije u spektrima i minimalizira grešku multivarijantnih kalibracija. Primjenom odgovarajućih algoritama za PLS, PCR i ILS na snimljene spektre kalibracijskog seta dobiven je dobar model, koji je odabran na temelju RMSECV i RMSEP vrijednosti. Isti model je primijenjen i na set s predviđenim vrijednostima i na kapsule sa smjesom ove tri ljekovite tvari. Određena je srednja vrijednost povrata za komercijalnu formulaciju te ostale analitičke izvedbene značajke (kalibracijska osjetljivost, selektivnost, granica dokazivanja, granica određivanja i analitička osjetljivost). Potvrđena je primjenjljivost predloženih metoda u analizama lijekova u fizičkim smjesama i u gotovim ljekovitim oblicima

Aptamer-based field-effect biosensor for tenofovir detection

During medical treatment it is critical to maintain the circulatory concentration of drugs within their therapeutic range. A novel biosensor is presented in this work to address the lack of a reliable point-of-care drug monitoring system in the market. The biosensor incorporates high selectivity and sensitivity by integrating aptamers as the recognition element and field-effect transistors as the signal transducer. The drug tenofovir was used as a model small molecule. The biointerface of the sensor is a binary self-assembled monolayer of specific thiolated aptamer and 6-mercapto-1-hexanol (MCH), whose ratio was optimized by electrochemical impedance spectroscopy measurements to enhance the sensitivity towards the specific target. Surface plasmon resonance, performed under different buffer conditions, shows optimum specific and little non-specific binding in phosphate buffered saline. The dose-response behavior of the field-effect biosensor presents a linear range between 1 nM and 100 nM of tenofovir and a limit of detection of 1.2 nM. Two non-specific drugs and one non-specific aptamer, tested as stringent control candidates, caused negligible responses. The applications were successfully extended to the detection of the drug in human serum. As demonstrated by impedance measurements, the aptamer-based sensors can be used for real-time drug monitoring

Advanced materials for geothermal energy applications

Usage of advanced materials and tools in geothermal energy applications become a trendy topic that captures a glance in the industry day by day. New technology materials such as fiber coatings, dressing materials and composites as well as new technology tools such as Distributed Temperature Sensing Systems and Distributed Thermal Perturbation Sensor allows an improved reservoir monitoring in harsh environments that have HTHP or high CO2 conditions. Thermal Infrared Remote Sensing tools that could be attached to a carrier like an aircraft, drone or a satellite and enables to describe temperature anomalies in forests, seabed, and land also pave the way of a robust identification of geothermal sources and hot spring waters. Tracers determine hydraulic connectivity between wells an gives an idea about the reservoir volume. Advanced drilling fluids are advantageous due to their light weight, tough structure which resists to corrosion compared with conventional ones and the developments promising to evolve these fluids with nanotechnology in close future. Advanced cements that developed by the aim of providing perfect zonal isolation opened the way of developing various cement types such as; foam cements, phosphate bonded, self-healing, and CO2 resistant cements. Apart from exploration phase, many inventions and developments that ensures lower health and safety risks, lower operating and maintenance costs and increases the energy efficiency in heat transfer and energy conversion sections of geothermal industry were gained a place in the market.In this chapter of the book, latest advances in geothermal industry materials and applications as well as latest technology tools which are more beneficial and efficient compared with the conventional methods are investigated in details. © 2021 Elsevier Inc. All rights reserved

Optimization of micellar-polymer drive in a stochastic reservoir [??????????? ???????????-??????????? ?????????? ??? ??????????????? ? ?????????????? ??????? ???????]

SPE Russian Petroleum Technology Conference 2019, RPTC 2019 -- 22 October 2019 through 24 October 2019 -- -- 1570612-s2.0-85084166560Micellar - Polymer drive process is one of the effective, proven and widely used non-thermal EOR methods which classified under chemical flooding. The process is preferable in reservoirs that don't have enough aquifer assistance and also in depleted reservoirs. A successful micellar-polymer flooding operation can be enabled by having correct data of parameters like reservoir pressure, mineral types in the reservoir, phase behavior of microemulsions, reservoir temperature, salinity data, buffer stability, micellar slug, and concentrations of the surfactants. In this study, A comprehensive literature review regarding on above parameters studied with field case studies worldwide. A Micellar- polymer drive process is applied on a stochastic reservoir and the optimization of the case performed by considering the mechanisms and limitations of micellar-polymer drive process, selection and design criteria, as well as the phase behavior changes during the process to have the most effective residual oil recovery. Parameters that enables an optimal recovery is described and used as optimization parameters in a full-physics commercial reservoir simulator. Typical Injection sequence that includes water flooding, polymer injection, polymer drive, polymer taper and chase water is applied for selected time periods. Changes of Oil saturation, water viscosity, adsorbed fluid, surfactant and polymer adsorption is simulated by using the optimal values of selected optimization parameters. General solution results are given with the optimal solution and all compared with the base case. It clarified that the Micellar-polymer drive optimization maximizes cumulative oil recovery in a reservoir that has a stochastically generated permeability distribution. © 2019, Society of Petroleum Engineer

Investigating the addition of enzymes in gluten-free flours - The effect on pasting and textural properties

A wide range of enzymes (fungal amylase, esterase, hemicellulase, glucose oxidase and transglutaminase) were added to gluten-free flours (buckwheat, corn and rice) at different concentrations (0, 1, 3, 5, 10 g/100 kg flour) to investigate the effects on pasting properties of flour and texture profiles of the flour gels. Concerning the pasting properties, fungal amylase enzyme consistently affected the flour properties. Breakdown of complex starch molecules into simpler sugars due to the enzyme activity decreased the overall viscosity parameters (at least trough viscosity by 50%, breakdown viscosity by 80%, final viscosity by 60% and setback viscosity by 67%) during the application of heating, shearing and cooling cycle. Increasing enzyme concentration decreased these values further due to increase in the rate of hydrolysis. Texture profiles of the flour gels showed good relation with pasting properties. Decreasing viscosity of gluten-free gels by enzymes caused reduction in the firmness of the gels. The hardest gel was found as corn flour at the highest amylase enzyme concentration (10 g/100 kg flour). However, the highest springiness, resilience, cohesiveness and adhesiveness value was observed for buckwheat starch gel. © 2016