The fundamentals and applications of polymer brush-modified membranes are reviewed. This new class of synthetic membranes is explored with an emphasis on tuning the membrane performance through polymer brush grafting. This work highlights the intriguing performance characteristics of polymer brush-modified membranes in a variety of separations. Polymer brushes are a versatile and effective means in designing membranes for applications in protein adsorption and purification, colloid stabilization, sensors, water purification, pervaporation of organic compounds, gas separations, and as stimuli responsive materials.

Traditional pharmaceutical manufacturing is based on a complex supply chain that is vulnerable to spikes in demand and interruptions. Continuous pharmaceutical production in compact modules is a potential solution that allows for drug manufacturing when and where it is needed with significantly shorter lead times. As part of the Pharmacy on Demand (PoD) initiative, we demonstrate the potential for end-to-end manufacturing of multiple drug substances in reconfigurable devices, under common industrial constraints, and within a challenging manufacturing time frame. A new set of refrigerator-sized modules was constructed for the synthesis, isolation, and formulation of several drugs, with focus on achieving high manufacturing throughputs, and allowing for the production of pharmaceutical tablets. Their operation is demonstrated with the synthesis and formulation of USP-compliant tablets of diazepam, diphenhydramine hydrochloride, and ciprofloxacin hydrochloride, as well as liquid formulations of lidocaine hydrochloride and atropine sulfate.

Although thermal desalination technology provides potable water in arid regions (e.g., Israel and the Gulf), its relatively high cost has limited application to less arid regions with large populations (e.g., California). Energy-intensive distillation is currently being replaced with less costly pressure- and electrically driven membrane-based processes. Reverse osmosis (RO) is a preferred membrane technology owing to process and pre- and posttreatment improvements that have significantly reduced energy requirements and cost. Further technical advances will require a deeper understanding of the fundamental science underlying RO. This includes determining the mechanism for water selectivity; elucidating the behavior of molecular water near polar and apolar surfaces, as well as the advantages and limitations of hydrophobic versus hydrophilic pores; learning the rules of selective water transport from nature; and designing synthetic analogs for selective water transport. Molecular dynamics simulations supporting experiments will play an important role in advancing these efforts. Finally, future improvements in RO are limited by inherent technical mass transfer limitations.

Protein‐fouling of membranes has negative effects on the wide applications of membrane materials, such as poly(vinylidene fluoride) (PVDF), poly(ether sulfone) (PES)/polysulfone (PSf). Zwitterionic materials have recently been used and identified from high throughput screens of large libraries of monomers to modify membranes due to their stable anti‐protein‐fouling properties. “Grafting from” polymerization is a technique involving monomers that are polymerized using an initiation reaction on the membrane surface. It is regarded as a simple, useful, and versatile modification approach to increase the anti‐fouling properties of a membrane. This strategy provides controllable introduction of graft chains with a high density and a long‐term chemical stability due to covalent attachment of graft chains. Graft density, chemistry, chain length, and conformation are all important parameters that need to be considered. This article presents a mini‐review of recent progress on the “grafting from” polymerization of zwitterionic monomers on the surfaces of PVDF and PES/PSf membranes, including an introduction of zwitterions and methods of graft polymerization. Various approaches such as free radical graft polymerization, photo‐induced graft polymerization, and plasma‐induced graft polymerization were compared based on uniformity and amount of grafted zwitterionic polymer, relative flux of modified membranes, simplicity and environment pollution of operation, and cost of technique. The application of different approaches and the performance of poly(zwitterion)‐grafted PVDF and PES/PSf membranes are summarized according to recent research. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 41781.

This paper presents a fully-continuous novel liquid-liquid-extraction (LLE) platform for the purification of nanoparticles. The use of multistage operation enhances the purity of the final stream without the expense of high solvent consumption. Two case studies, purification of CdSe quantum dots in organic solvent and that of gold nanoparticles in water, demonstrate that the LLE platform is versatile, non-destructive, and highly efficient.