Environmental-stimuli-responsive smart materials are marvelous materials with the capability to sense their environments’ signals, process these data and respond. One or more of their properties can be significantly changed in a controlled fashion by responding to external stimuli, such as temperature, pH, stress, moisture, and electric or magnetic fields. Nowadays, stimuli-responsive smart materials are attracting ever-increasing attention from all over the world. Such smart materials make it possible to design and fabricate artificial biomimetic smart membranes.

Bionic technology is endlessly bringing us new ideas, new principles, new approaches and new theories from the natural world for developing the novel high-tech world. Biomembranes in nature with environmental-stimuli-responsive channels across their membranes provide inspiration for membrane scientists and technologists to develop artificial biomimetic smart membranes, which are highly attractive for achieving more advanced and comprehensive membranes with not only a selective factor but also an environmental-stimuli-responsive factor and gating factor.

As artificial biomimetic membranes, smart membranes that are able to respond to environmental stimuli are attracting ever-increasing interest from various fields. Their surface characteristics and/or permeation properties, including hydraulic permeability (pressure-driven convective flow of solvents) and diffusional permeability (concentration-driven molecular diffusion of solutes), can be dramatically controlled or adjusted self-regulatively in response to small chemical and/or physical stimuli in their environments, such as temperature, pH, ionic strength, electrical field, photo irradiation, glucose concentration, oxidoreduction and/or chemical or biological species. Such environmental-stimuli-responsive smart membranes could find myriad applications in numerous fields ranging from controlled release to chemical separation, water treatment, bioseparation, chemical sensors, chemical valves, tissue engineering, etc. The development of smart membranes is of both scientific and technological importance.

This book reviews the latest achievements on the topic of smart membranes from all over the world. The contents in this book cover novel design and fabrication strategies as well as novel applications of smart membranes, and combine different strategies and approaches on controlling the structures and the performances of smart membranes. Thus, this book delivers new insights and fundamentals for both professionals and newcomers in the related fields.

The book is composed of 15 chapters. Chapter 1 gives a brief introduction to smart membranes, including the definition, design strategies, fabrication methods, categories, applications, and so on. Chapter 2, contributed by Prof. Rui Xie and Prof. Liang-Yin Chu at Sichuan University, introduces novel methods for fabrication of smart gating membranes by assembling responsive nanogels on membrane pores as functional gates via vapor-induced phase transition. Chapter 3, contributed by Prof. Thomas Schafer at University of the Basque Country, introduces novel DNA-sandwich gated membranes. Chapter 4, contributed by Prof. Ranil Wickramasinghe at University of Arkansas, introduces the development of magnetically responsive membranes. Chapter 5, contributed by Prof. Zhuang Liu and Prof. Liang-Yin Chu at Sichuan University, introduces novel smart gating membranes that can specifically recognize potassium ions and lead(ii) ions. Chapter 6, contributed by Prof. Jinying Yuan at Tsinghua University, presents novel smart membranes that can respond to CO₂. Chapter 7, contributed by Prof. James D. Batteas at Texas A&M University, introduces a novel synthetic approach to fabricate solute- and temperature-responsive smart membranes by covalent layer-by-layer assembly. Chapter 8, contributed by Prof. Wei Wang and Prof. Liang-Yin Chu at Sichuan University, presents novel smart-membranes-in-microchips that can be used for real-time detection. Chapter 9, contributed by Prof. Takeo Yamaguchi at Tokyo Institute of Technology, introduces biomolecule-recognition smart gating membranes. Chapter 10, contributed by Prof. Xiao-Jie Ju and Prof. Liang-Yin Chu at Sichuan University, presents smart microcapsule membranes with different structures and functions for controlled release of drugs. Chapter 11, contributed by Prof. Mathias Ulbricht at University of Duisburg-Essen, introduces smart polymeric membranes with magnetic nanoparticles for switchable separation. Chapter 12, contributed by Prof. Matthias Wessling at RWTH Aachen University, introduces artificial oscillating membrane systems. Chapter 13, contributed by Prof. Huanting Wang at Monash University, presents thermo-responsive membranes with switchable superhydrophilicity and superhydrophobicity for oil–water separation. Chapter 14, contributed by Prof. Yung Chang at Chung Yuan Christian University, introduces smart biomedical membranes for blood separation. Chapter 15 gives some concluding remarks and perspectives for smart membranes.

This book is a valuable reference book for designing and fabricating artificial biomimetic smart membranes for various application purposes and an update on the current status of smart membranes and is suitable for a wide general readership including chemists, chemical engineers, materials researchers, pharmaceutical scientists, biomedical researchers, and students in related fields.

The editor and authors of this book would like to acknowledge the kind invitation from Dr Leanne Marle at the Royal Society of Chemistry, and the kind help from Dr Leanne Marle, Connor Sheppard and Dr Robin Driscoll at the Royal Society of Chemistry during the preparation and publication of this book.

Liang-Yin Chu

Sichuan University

China