During the last 10 years, membrane chromatography (MC) has been increasingly reported for biomolecule purification at both small and large scales. Although, several axial and radial flow MC devices are commercialized, the effect of the device dimensions on the adsorption performance has not been fully investigated. In this study, axial and radial flow anion ion-exchange MC devices were used for bovine serum albumin (BSA) adsorption.
View Article and Find Full Text PDFThe active and selective transport of glucose and glycerol was carried out using electrophoresis and artificial enzymatic membranes. These positively charged composite membranes carry, on the face adjacent to the donor compartment of an electrophoresis module, a specific kinase (hexokinase or glycerokinase) and, on the opposite face, an alkaline phosphatase (ALP). Phosphorylation of the neutral substrate (glucose or glycerol) on the donor side by the kinase generates a negatively charged phosphorylated substrate, whose transmembrane migration is promoted by an electric field and by the membrane's positive charge.
View Article and Find Full Text PDFA complete kinetic modeling of the polymer-derived ceramics (PDCs) route is achieved for the first time through the investigation of the solid-state decomposition of a typical melt-spinnable poly[B-(methylamino)borazine] into boron nitride fibers at various heating rates. Through the use of the Lorentz fitting approach, it is shown that the two-step weight loss associated with the polymer-to-ceramic conversion is governed by a complex interplay of five diffusion-type transport mechanisms that are independent of the applied heating schedule. The application of the Friedman method to dynamic thermogravimetry data yields Ea and ln A values that are seen to increase with the extent of the ceramic conversion from region one (Ea = 38.
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