(4cb) Tailoring the Membrane Structure: the Challenging Path From Nano- to Process Scale

Marchetti, P., Imperial College London

In recent years the application of membrane technology to molecular separation processes has stimulated interest and showed great potential in a number of industrial fields. In the pharmaceutical industry, as an example, spending on R&D into new medicines has been enormously increased over the past decades and nanofiltration (NF) has been proposed as an emerging technology for concentrating and purifying Active Pharmaceutical Ingredients, with a number of advantages, compared to conventional downstream techniques. During my PhD at Imperial College London, and simultaneous enrollment as Early Stage Researcher at Lonza AG (Switzerland), my research in the field focused on two main aspects of membrane technology: the design and development of membrane processes for purification/separation of peptides, and the fundamental understanding and modeling of transport processes. The application of NF membranes was investigated for model peptides and the separation mechanism was analyzed from a fundamental point of view. An improved model for solvent permeation through nanofiltration and ultrafiltration membranes was developed and the importance of molecular affinity effects on the nanofiltration of peptides in aqueous and organic solvent mixtures was identified. The advantages of Design of Experiments methods and statistical modeling were combined with the description of basic filtration processes for concentration and diafiltration. Finally, an efficient strategy for the fragment condensation of peptides was developed, by integrating membrane technology into the synthesis step. This work demonstrated that NF is a solid and competitive technique for peptide applications.

One of the still challenging tasks of membrane technology is the fabrication of porous materials, with tunable intrinsic structure and controllable performance. Recently, I have been working for the development of new membranes from pre-fabricated nanostructures, to be used in both aqueous and organic solutions, and for the understanding of correlated phenomena of adhesion, wetting and spreading.  

From a more general point of view, my research interest covers the area of both theoretical and experimental multi-scale approaches in novel materials and nanoscale phenomena. I am interested in the fabrication of functional materials from organized particles, on strategies for colloidal assembly and potential applications of micro- and nanoparticles structures in materials. The challenge of this research is in the development of efficiently controlled fabrication procedures, solving the issues of scalability and precision in controlling porosity and strength of interactions. Furthermore, I am interested in understanding the physico-chemical and structural properties of such materials and the transport mechanism through the matrix. This research opens to various fields, apart from membrane applications, since there is a broad spectrum of uses and applications of nanostructured materials in medicine, manufacturing and materials, energy and environment.