2,4-Dichlorophenoxyacetic acid (2,4-D) is an herbicide and is among the most widely distributed pollutant in the environment and wastewater. Herein is presented a complete comparison of adsorption performance between two different magnetic carbon nanomaterials: graphene oxide (GO) and its reduced form (rGO). Magnetic functionalization was performed employing a coprecipitation method, using only one source of Fe, requiring low energy, and potentially allowing the control of the amount of incorporated magnetite.
View Article and Find Full Text PDFJ Pharm Biomed Anal
January 2024
Microwave-assisted wet digestion (MAWD) using only HO was proposed for oxidizing active pharmaceutical ingredients (APIs) for hypertension treatment and subsequent determination by inductively coupled plasma optical emission spectrometry (ICP-OES). Diltiazem hydrochloride (DIL) presented the most refractory characteristic for oxidation using MAWD-HO. This proposed MAWD-HO method was validated for specificity, accuracy, and precision according to United States Pharmacopeia (USP) Chapter 233 guidelines.
View Article and Find Full Text PDFDrying rice in a single layer in a silo-dryer-aerator allows uniform drying. The objective of this study was to evaluate the physical, physicochemical, and morphological quality of rice grain cultivars (IRGA 424, BRS Pampeira, and Guri INTA) in the lower (initial time) and upper (final time) layers in a silo-dryer-aerator, employing single-layer loading at low temperatures, using the methods of near-infrared spectroscopy, X-ray diffraction analysis, scanning electron microscopy, and multivariate statistical analysis. Drying rice in silo-dryer-aerator attenuated the moisture diffusivity in the grains, minimizing its effects on the physical, physicochemical, and morphological properties of the grains.
View Article and Find Full Text PDFHerein, tetracycline adsorption employing magnetic chitosan (CS·FeO) as the adsorbent is reported. The magnetic adsorbent was synthesized by the co-precipitation method and characterized through FTIR, XRD, SEM, and VSM analyses. The experimental data showed that the highest maximum adsorption capacity was reached at pH 7.
View Article and Find Full Text PDFMany efforts have been recently made to improve the digestion efficiency by using powerful equipment or by using an auxiliary reagent. In this work, an alternative method is reported, which explores a digestion system based on a single reaction chamber (SRC) technology pressurized with O for reducing the amount of acid, without impairing the digestion efficiency. Before digestion, the system was pressurized with compressed air (20 bar, 20% O) while the temperature was evaluated from 180 up to 270 °C.
View Article and Find Full Text PDFUnlabelled: Nutritional support strongly influence the nutritional status of the surgical neoplastic patients. This study aimed to evaluate the influence of food consumption on the perioperative nutritional status of hospitalized patients with neoplasia of the upper (UGIT) and lower (LGIT) gastrointestinal tract.
Method: Observational, longitudinal, and prospective study.
Diabetes is a set of metabolic disorders that affect >400 million individuals worldwide. Empagliflozin belongs to the gliflozin class and is used orally to treat type 2 diabetes. In this study, a simple stability-indicating HPLC-UV method was developed to assay empagliflozin tablets and its main photoproduct was identified by high-resolution mass spectrometry.
View Article and Find Full Text PDFGood air quality is documented as a significant factor of social justice. The human health hazards associated with air pollution are not distributed equally across cities; the most vulnerable people are more exposed to ambient air as they commute to work and wait for buses or trains at the stations. Aerosols play important roles in atmosphere quality and the climate; their oxidation at the nanoscale level may possibly increase the reactivity and toxicity of atmospheric particulates.
View Article and Find Full Text PDFA simple, rapid, low-cost method was proposed for the imaging of biofilms on metallic surfaces using an infrared camera. Stainless steel coupons were cooled to generate a thermal gradient in relation to biofilm for active thermography (AT). Both cooling and image acquisition times were optimized and the images obtained with AT were compared with those from scanning electron microscopy.
View Article and Find Full Text PDFFood Res Int
April 2020
The aim of this study was to investigate the influence of hi-maize, inulin, and rice bran in the survival of Lactobacillus acidophilus LA-5 in pectin microparticles obtained by internal gelation and subjected to freeze-drying. For this, the development of a matrix capable of extending Lactobacillus acidophilus viability to develop new functional foods was emphasized. Microparticle size, encapsulation efficiency, probiotic survivability after gastrointestinal simulation, and storage stability were analyzed.
View Article and Find Full Text PDFRationale: A method for the determination of rare earth elements in carbonatite rocks by inductively coupled plasma mass spectrometry (ICP-MS) was developed.
Methods: An alkaline rock, carbonatite, was submitted to ultrasound-assisted extraction (USAE) using an ultrasound bath, a cup horn system or an ultrasound probe. The main USAE parameters were evaluated, such as extraction time (1 to 30 min), extraction temperature (20 to 100°C) and ultrasound amplitude (10 to 100%).
Lactobacillus acidophilus were encapsulated by complex coacervation followed by transglutaminase crosslinking, aiming to improve the resistance of the microcapsules and improve the protection for probiotics. Subsequently, microcapsules were dried by freeze drying. The encapsulation efficiency, morphology, thermal resistance, gastrointestinal simulation and storage stability were analysed for wet and dry forms.
View Article and Find Full Text PDFThe production and use of nanoparticles (NPs) in different fields increased in the last years. However, some NPs have toxicological properties, making these materials potential emerging pollutants. Therefore, it is important to investigate the uptake, transformation, translocation, and deposition of NPs in plants.
View Article and Find Full Text PDFA versatile, rapid and safe green method for chlorine and sulfur determination using ion chromatography in cereals and legumes was developed. Microwave-induced combustion was evaluated for sample preparation. Ultrapure water and alkaline solutions were assessed for absorption of the analytes.
View Article and Find Full Text PDFThis chapter focuses on bioimaging in metallomics, which involves metal and metalloids distribution in animal tissues. It starts with laser ablation-inductively coupled plasma-mass spectrometry followed by secondary ion mass spectrometry, synchrotron-based X-ray fluorescence, and electron microscopy, including transmission electron microscopy, scanning electron microscopy, and energy-dispersive X-ray spectroscopy. The basic principles of these techniques and their application for qualitative and quantitative imaging of elements are presented.
View Article and Find Full Text PDFRare earth elements (REEs) have several applications but the effects on environment are not well known. Therefore, the aim of this work is to establish a method for direct solid sample analysis by laser ablation-inductively coupled plasma mass spectrometry (LA-ICP-MS) to evaluate the concentration and distribution of REEs in cultivated and non-cultivated soil. Samples were collected in two areas to 40 cm of depth.
View Article and Find Full Text PDFA calibration strategy using porous nylon disks and reference solutions is proposed for the first time for matrix matching and determination of As, Ba, Cd, Cr, Pb, Sr and Zn in polymers by laser ablation-inductively coupled plasma mass spectrometry (LA-ICP-MS). Polymer samples commonly used in contact with food were analyzed. The procedure consists on the use of porous nylon disks as support for a dried droplet reference solution.
View Article and Find Full Text PDFIn view of the increasing demand for rare-earth elements (REE) in many areas of high technology, alternative methods for the extraction of these elements have been developed. In this work, a process based on the use of ultrasound for the extraction of REE from carbonatite (an igneous rock) is proposed to avoid the use of concentrated reagents, high temperature and excessive extraction time. In this pioneer work for REE extraction from carbonatite rocks in a preliminary investigation, ultrasonic baths, cup horn systems or ultrasound probes operating at different frequencies and power were evaluated.
View Article and Find Full Text PDFThis paper reports the development of a method of simultaneous determination of iron and nickel in fluoropolymers by high-resolution continuum source graphite furnace atomic absorption spectrometry (HR-CS GF AAS) with direct solid sampling. In order to carry out simultaneous measurements, both the main resonance line of nickel (232.003nm) and the adjacent secondary line of iron (232.
View Article and Find Full Text PDFIn this work a green digestion method which only used H2O2 as an oxidant and high temperature and pressure in the single reaction chamber system (SRC-UltraWave™) was applied for subsequent elemental determination by inductively coupled plasma-based techniques. Milk powder was chosen to demonstrate the feasibility and advantages of the proposed method. Samples masses up to 500mg were efficiently digested, and the determination of Ca, Fe, K, Mg and Na was performed by inductively coupled plasma optical emission spectrometry (ICP-OES), while trace elements (B, Ba, Cd, Cu, Mn, Mo, Pb, Sr and Zn) were determined by inductively coupled plasma mass spectrometry (ICP-MS).
View Article and Find Full Text PDFAn alternative method for the quantification of sulphametoxazole (SMZ) and trimethoprim (TMP) using diffuse reflectance infrared Fourier-transform spectroscopy (DRIFTS) and partial least square regression (PLS) was developed. Interval Partial Least Square (iPLS) and Synergy Partial Least Square (siPLS) were applied to select a spectral range that provided the lowest prediction error in comparison to the full-spectrum model. Fifteen commercial tablet formulations and forty-nine synthetic samples were used.
View Article and Find Full Text PDFDrugs of long-term use may cause the accumulation of chemical compounds in human body. Therefore, the evaluation and structure characterization of synthesis and degradation impurities is substantial to guarantee drug safety and successful pharmaceutical therapy. The present work evaluated the anticoagulant rivaroxabana (RIV) under stress conditions in order to elucidate the chemical structure of major degradation products (DPs) formed after drug exposition to acid and alkaline hydrolysis, and UVC radiation.
View Article and Find Full Text PDFIn this work a method for active pharmaceutical ingredients (APIs) digestion using the single reaction chamber (SRC-UltraWave™) system was proposed following the new recommendations of United States Pharmacopeia (USP). Levodope (LEVO), primaquine diphosphate (PRIM), propranolol hydrochloride (PROP) and sulfamethoxazole (SULF) were used to evaluate the digestion efficiency of the proposed method. A comparison of digestion efficiency was performed by measuring the carbon content and residual acidity in digests obtained using SRC and in digests obtained using conventional microwave-assisted digestion system (Multiwave(TM)).
View Article and Find Full Text PDFA method based on microwave-induced combustion (MIC) was developed for fish (Engraulis anchoita) digestion and subsequent determination of As, Cd, Co, Cr, Cu, Fe, Mn, Mo, Ni, Se, and Zn by inductively coupled plasma mass spectrometry (ICP-MS). A reflux step (5 min) was applied to improve absorption and recovery of analytes. Nitric acid was investigated as absorbing solution and suitable results were achieved using 5 mol L⁻¹ HNO₃.
View Article and Find Full Text PDFFluorine, chlorine, bromine, and iodine have been studied in biological samples and other related matrices owing to the need to understand the biochemical effects in living organisms. In this review, the works published in last 20 years are covered, and the main topics related to sample preparation methods and analytical techniques commonly used for fluorine, chlorine, bromine, and iodine determination in biological samples, food, drugs, and plants used as food or with medical applications are discussed. The commonest sample preparation methods, as extraction and decomposition using combustion and pyrohydrolysis, are reviewed, as well as spectrometric and electroanalytical techniques, spectrophotometry, total reflection X-ray fluorescence, neutron activation analysis, and separation systems using chromatography and electrophoresis.
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