Enhanced physicochemical and antifungal properties of starch bionanocomposites reinforced with nanocellulose and functionalized with AgNPs derived from cocoa bean shell.

This study explored the synergistic combination of silver nanoparticles (AgNPs), eucalyptus-derived nanofibrillated cellulose (NFC) and cassava starch to develop bionanocomposites with advanced properties suitable for sustainable and antifungal packaging applications. The influence of AgNPs synthesized through a green method using cocoa bean shell combined with varying concentrations of NFC were investigated. Morphological (scanning electron microscopy and atomic force microscopy), optical (L*, C*, °hue, and opacity), chemical (Fourier transform infrared spectroscopy), mechanical (puncture force, tensile strength, and Young's modulus), rheological (flow curve and frequency sweeps, strain, and stress), barrier, and hydrophilicity properties (water vapor permeability, solubility, wettability, and contact angle), as well as the antifungal effect against pathogens (Botrytis cinerea, Penicillium expansum, Colletotrichum musae, and Fusarium semitectum), were analyzed.

Detection of coffee adulteration with soybean and corn by capillary electrophoresis-tandem mass spectrometry.

The detection of coffee adulteration with soybean and corn by capillary electrophoresis-tandem mass spectrometry was accomplished by evaluating the monosaccharides profile obtained after acid hydrolysis of the samples. The acid hydrolysis, using HSO as a catalyst, increases the ionic strength of the sample impairing the electrophoretic separation. Therefore, Ba(OH) was used to both neutralize the medium and reduce the content of sulfate by precipitation of BaSO.

Phytochemical characterization of the Vochysia rufa (Vochysiaceae) extract and its effects on oxidative stress in the pancreata of streptozotocin-induced diabetic rats.

Aqueous extract of macerated Vochysia rufa stem bark has been commonly used in the treatment of diabetes. Therefore, we evaluated the antihyperglycemic and antioxidant effects of an extract of V. rufa on the pancreata of streptozotocin (STZ)-induced diabetic rats.

Amphetamine and derivatives in natural weight loss pills and dietary supplements by capillary electrophoresis-tandem mass spectrometry.

A capillary electrophoresis-tandem mass spectrometry (CE-MS/MS) method for amphetamine (AM), phentermine (PTM), methamphetamine (MAM), methylenedioxyamphetamine (MDA), methylenedioxymethamphetamine (MDMA), and methylenedioxyethylamphetamine (MDEA) in commercial samples of homeopathic and phytotherapic medicines and dietary supplements is presented. The samples were submitted to a modified QuEChERS extraction procedure (at apparent pH 13) followed by electrophoretic separation in 0.1molL formic acid electrolyte (pH 2.

Formation of isomers of anionic hemiesters of sugars and carbonic acid in aqueous medium.

Hemiesters of carbonic acid can be freely formed in aqueous media containing HCO3(-)/CO2 and mono- or poly-hydroxy compounds. Herein, (13)C NMR spectroscopy was used to identify isomers formed in aqueous solutions of glycerol (a prototype compound) and seven carbohydrates, as well as to estimate the equilibrium constant of formation (Keq). Although both isomers are formed, glycerol 1-carbonate corresponds to 90% of the product.

Fast production of microfluidic devices by CO2 laser engraving of wax-coated glass slides.

Glass is one of the most convenient materials for the development of microfluidic devices. However, most fabrication protocols require long processing times and expensive facilities. As a convenient alternative, polymeric materials have been extensively used due their lower cost and versatility.

Determination of biogenic amines in beer and wine by capillary electrophoresis-tandem mass spectrometry.

A capillary electrophoresis-tandem mass spectrometry (CE-MS/MS) method for the simultaneous assessment of nine biogenic amines (spermine, spermidine, putrescine, cadaverine, histamine, phenylethylamine, tryptamine, tyramine, and urocanic acid) in commercial samples of beer and wine is introduced. The samples were submitted to a simple clean-up step with poly(vinylpolypyrrolidone) followed by filtration. Electrophoretic separation in a polyvinyl alcohol (PVA)-coated capillary using 0.

Serological and molecular evidence of hepadnavirus infection in swine.

Introduction And Objective: Recently, investigations in a swine herd identified evidence of the existence of a novel member of the Hepadnavirus family endemic in swine. The aim of this study was to investigate the serological and molecular markers of Hepadnavirus circulation in Brazilian domestic swine and wild boar herds, and to evaluate the identity with HBV and other Hepadnaviruses reported previously.

Materials And Methods: For the study, 376 swine were screened for hepatitis B virus serological markers.

Determination of halosulfuron-methyl herbicide in sugarcane juice and tomato by capillary electrophoresis-tandem mass spectrometry.

A capillary electrophoresis-tandem mass spectrometry (CE-MS/MS) method for the determination of halosulfuron-methyl (HSU) residue in samples of sugarcane juice and tomato is introduced and validated. The samples were submitted to a QuEChERS extraction procedure followed by electrophoretic separation in NH4HCO3 electrolyte (adjusted to pH 8.5) and detection by electrospray-tandem mass spectrometry.

A simple approach to compensate the suction caused by the electrospray ionization source in capillary electrophoresis-mass spectrometry systems.

ESI sources continuously consume the liquid at the tip of the capillary, which causes the dragging of the BGE. The laminar nature of this flow causes the broadening of the peaks and loss of separation efficiency. The usual solution for this problem is to compensate this phenomenon by reducing the pressure at the inlet vial by either leveling of this vial or pumping off the air that is over it.

From sample processing to quantification: a full electrochemical approach for neutral analyte derivatization, capillary electrophoresis separation, and contactless conductivity detection.

A thin-layer electrochemical flow cell coupled to capillary electrophoresis with contactless conductivity detection (EC-CE-C(4)D) was applied for the first time to the derivatization and quantification of neutral species using aliphatic alcohols as model compounds. The simultaneous electrooxidation of four alcohols (ethanol, 1-propanol, 1-butanol, and 1-pentanol) to the corresponding carboxylates was carried out on a platinum working electrode in acid medium. The derivatization step required 1 min at 1.

Incident HIV infection in a high-risk, homosexual, male cohort in Rio de Janeiro, Brazil.

An HIV seroincidence study was conducted to identify a high-risk population for HIV prevention trials. Inclusion criteria were male gender, homosexual behavior, age between 18 and 50 years, and negative HIV serostatus; 862 study subjects were screened and 753 were enrolled and observed during follow-up for a mean of 1.5 years.