ABSTRACT
Fe3O4 magnetic nanoparticles modified with tetraethyl orthosilicate and bovine serum albumin (Fe3O4@TEOS@BSA) were synthesized and efficiently used to separate lysozyme from egg white. Glutaraldehyde was used to crosslink the bovine serum albumine molecules around the nanoparticles. The surface modifications were attested by transmission electron microscopy, infrared spectroscopy, thermogravimetry analysis, and zeta potential. The material was thermally stable, and its surface charge was pH-dependent. The best lysozyme adsorption and desorption were obtained at pHs 10.0 and 5.0, respectively. The pseudo-second-order model fitted well into the lysozyme adsorption kinetic data and the time for the equilibrium was 15 min. The adsorption equilibrium results were best described by the Freundlich model. Fe3O4@TEOS@BSA particles were very efficient to extract lysozyme from chicken egg, according to the SDS-PAGE analyses. The extracted molecules maintained their enzymatic activity in about 90%. Fe3O4@TEOS@BSA particles were easily recycled, with their reuse being possible 5 times with the same performance.
Subject(s)
Egg White/chemistry , Magnetic Iron Oxide Nanoparticles/chemistry , Metal Nanoparticles/chemistry , Muramidase/isolation & purification , Serum Albumin, Bovine/chemistry , Adsorption , Animals , Chickens , Ferric Compounds/chemistry , Hydrogen-Ion Concentration , Kinetics , Microscopy, Electron, Transmission , Muramidase/chemistry , Silanes/chemistry , ThermogravimetryABSTRACT
The development and validation of an innovative, simple, rapid, selective and sensitive vortex-assisted liquid-liquid microextraction-gas chromatography- mass spectrometry (VALLME-GC/MS) method to seven triazole fungicides in urine is reported. The confidence parameters were exhaustive evaluated and linearity (r > 0.99), precision (below 15%, to quality controls, and 20%, to lower limit of quantification), accuracy and robustness were adequate for the analysis of cyproconazole, epoxiconazole, metconazole, tebuconazole, triadimenol, propiconazole and triadimefon. To assess the applicability of the method, analyses were performed in volunteers exposed to triazoles in the last 30 days. The method demonstrated satisfactory analytical performance, with sufficient detectability to be applied as a potential tool to biomonitoring individuals exposed to the seven evaluated fungicides.
