An Innovative Approach for Sorptive Separation of Amphiphilic Biomolecules Applying High Hydrostatic Pressure

Abstract

An innovative approach to separate amphiphilic biomolecules in a fixed bed adsorption experimental set-up is discussed and experimental results are presented. High hydrostatic pressure of up to 360 MPa is utilized to control the sorption equilibrium. Major advantages of this approach are that no auxiliary substances are required for the separation that have to be removed afterwards. Furthermore, of the two physical parameters pressure and temperature that can be used to control reaction or sorption equilibria, pressure is the less harmful one towards the activity of biomolecules. To realize this approach, interdisciplinary researches were necessary. The surfaces of different silica gels were chemically modified in order to synthesize adsorbents with the desired properties. Two high pressure devices were designed and built. One is an circulation plant to investigate equilibrium states. It was utilized to record adsorption isotherms under a pressure of up to 300 MPa. The second one is a semi-continuous set-up for a fixed bed reactor. It was hydrodynamically characterized and afterwards used to look into breakthrough curves and separation cycles. The adsorption capacity of the tailor made adsorbents and its pressure dependency was examined via these plants in equilibrium (isotherm) and dynamic (breakthrough) experiments. Therefore, the nonionic surfactant Triton X-100 was applied as a model substance for e.g. glycolipids, which are within the scope of the separation method.