Sensing Techniques Involving Thin Films for Studying Biomolecular Interactions and Membrane Fouling Phenomena

Abstract

Interfacial phenomena are ubiquitous in sensing and separation applications involving membranes. In fact, their presence might strongly determine the effi ciency of the overall sensing or separation system, if not even deteriorate its performance with time as is the case in membrane separations (fouling). Characterization of these phenomena at the earliest possible stage is therefore indispensable in order to minimize their detrimental impact. Th is chapter discusses two advanced surface characterization techniques for this purpose, quartz crystal microbalance with dissipation monitoring (QCM-D) and surface plasmon resonance (SPR), and how they can be employed to provide valuable and complementary information on molecular adsorption phenomena occurring at a very early stage on polymer membranes.

A review of in situ real-time monitoring techniques for membrane fouling in the biotechnology, biorefinery and food sectors

“…Combinations and comparison of SPR with other tools, such as atomic force microscopy (AFM), surface acoustic waves, quartz crystal microbalance with dissipation (QCM-D) or Raman spectroscopy [63,66,62,70] have provided more insight into adsorption processes and have helped to verify findings. The combination of SPR with QCM-D allowed the differentiation between dry absorbed protein mass and wet adsorbed protein mass [71], while the displacement of one protein in the adsorption layer by another was determined by the combination of SPR and AFM [63].…”