Recombinant protein purification using gradient assisted simulated moving bed hydrophobic interaction chromatography. Part II: process design and experimental validation.

In the first part of this work adsorption isotherm parameters were acquired to describe the migration of recombinant streptokinase in Butyl Sepharose columns at different salt concentrations. Based on these results, a simulated moving bed (SMB) chromatographic process was designed and realised, which exploits a two-step salt gradient and allows the continuous separation of streptokinase from contaminants present in a clarified Escherichia coli cell lysate solution. This second part describes the design of the three-zone open-loop gradient SMB process applying both equilibrium theory and an equilibrium stage model and presents results of a series of experiments aiming to obtain pure streptokinase.

Recombinant protein purification using gradient-assisted simulated moving bed hydrophobic interaction chromatography. Part I: selection of chromatographic system and estimation of adsorption isotherms.

The design of gradient simulated moving bed (SMB) chromatographic processes requires an appropriate selection of the chromatographic system followed by the determination of adsorption isotherm parameters in the relevant range of mobile phase conditions. The determination of these parameters can be quite difficult for recombinant target proteins present in complex protein mixtures. The first part of this work includes the estimation of adsorption isotherm parameters for streptokinase and a lumped impurity fraction present in an Escherichia coli cell lysate for a hydrophobic interaction chromatography (HIC) matrix.

Is there a familial overlap between dementia and other psychiatric disorders?

Background: Cognitive and psychiatric features are important components of dementia. Early onset dementia (EOD) has been found to be associated with a greater genetic basis. If this is the case, EOD could have genetic association with psychiatric illnesses, given the presence of more behavioral disturbances in this condition.