A gel is a semi-solid that can have properties ranging from soft and weak to hard and tough. Gels are defined as a substantially dilute cross-linked system, which exhibits no flow when in the steady-state, although the liquid phase may still diffuse through this system. A gel has been defined phenomenologically as a soft, solid or solid-like material consisting of two or more components, one of which is a liquid, present in substantial quantity.
Soft matter or soft condensed matter is a subfield of condensed matter comprising a variety of physical systems that are deformed or structurally altered by thermal or mechanical stress of the magnitude of thermal fluctuations. These materials share an important common feature in that predominant physical behaviors occur at an energy scale comparable with room temperature thermal energy, and that entropy is considered the dominant factor. At these temperatures, quantum aspects are generally unimportant. Soft materials include liquids, colloids, polymers, foams, gels, granular materials, liquid crystals, flesh, and a number of biomaterials. When soft materials interact favorably with surfaces, they become squashed without an external compressive force. Pierre-Gilles de Gennes, who has been called the "founding father of soft matter," received the Nobel Prize in Physics in 1991 for discovering that methods developed for studying order phenomena in simple systems can be generalized to the more complex cases found in soft matter, in particular, to the behaviors of liquid crystals and polymers.
A hydrogel is a biphasic material, a mixture of porous, permeable solids and at least 10% by weight or volume of interstitial fluid composed completely or mainly by water. In hydrogels the porous permeable solid is a water insoluble three dimensional network of natural or synthetic polymers and a fluid, having absorbed a large amount of water or biological fluids. These properties underpin several applications, especially in the biomedical area. Many hydrogels are synthetic, but some are derived from nature. The term 'hydrogel' was coined in 1894.
A nerve guidance conduit is an artificial means of guiding axonal regrowth to facilitate nerve regeneration and is one of several clinical treatments for nerve injuries. When direct suturing of the two stumps of a severed nerve cannot be accomplished without tension, the standard clinical treatment for peripheral nerve injuries is autologous nerve grafting. Due to the limited availability of donor tissue and functional recovery in autologous nerve grafting, neural tissue engineering research has focused on the development of bioartificial nerve guidance conduits as an alternative treatment, especially for large defects. Similar techniques are also being explored for nerve repair in the spinal cord but nerve regeneration in the central nervous system poses a greater challenge because its axons do not regenerate appreciably in their native environment.
Nicholas (Nikolaos) A. Peppas is a chemical and biomedical engineer whose leadership in biomaterials science and engineering, drug delivery, bionanotechnology, pharmaceutical sciences, chemical and polymer engineering has provided seminal foundations based on the physics and mathematical theories of nanoscale, macromolecular processes and drug/protein transport and has led to numerous biomedical products or devices.
Edward Wilson Merrill was an American biomaterials scientist. He was one of the founders of bioengineering, and specifically the biomedical engineering field it developed from chemical engineering. Merrill was born to Edward Clifton Merrill (1881–1949), a chemical engineer and chief chemist of the United Drug Company (Rexall) and Gertrude Wilson (1895–1978).
David J. Pine is an American physicist who has made contributions in the field of soft matter physics, including studies on colloids, polymers, surfactant systems, and granular materials. He is Professor of Physics in the NYU College of Arts and Science and Chair of the Department of Chemical and Biomolecular Engineering at the NYU Tandon School of Engineering.
Molly S. Shoichet, is a Canadian science professor, specializing in chemistry, biomaterials and biomedical engineering. She was Ontario's first Chief Scientist. Shoichet is a biomedical engineer known for her work in tissue engineering, and is the only person to be a fellow of the three National Academies in Canada.
Peter Nicholas Pusey is a British physicist. He is an Emeritus Professor of Physics at the School of Physics and Astronomy of the University of Edinburgh.
Ashish Kishore Lele is an Indian chemical engineer, rheologist and the Director of the National Chemical Laboratory, Pune. He is known for his researches on micro and mesostructure of polymers and is an elected fellow of the Indian Academy of Sciences, and the Indian National Academy of Engineering. The Council of Scientific and Industrial Research, the apex agency of the Government of India for scientific research, awarded him the Shanti Swarup Bhatnagar Prize for Science and Technology, one of the highest Indian science awards for his contributions to Engineering Sciences in 2006. He received the Infosys Prize in 2012.
Rosemarie Wesson is the Associate Dean of Research at City College of New York. She was the first African-American woman to receive a PhD in chemical engineering from the University of Michigan. She has worked at the National Science Foundation, Louisiana State University and Dow Chemical Company.
Horst Henning Winter is a German American chemical engineer, educator and researcher. He is a distinguished professor at the University of Massachusetts Amherst, and was the executive editor of Rheologica Acta from 1989 to 2016, where he has served as honorary editor since 2017.
Kristi Lynn Kiick is the Blue and Gold Distinguished Professor of Materials Science and Engineering at the University of Delaware. She studies polymers, biomaterials and hydrogels for drug delivery and regenerative medicine. She is a Fellow of the American Chemical Society, the American Institute for Medical and Biological Engineering, and of the National Academy of Inventors. She served for nearly eight years as the deputy dean of the College of Engineering at the University of Delaware.
Ronald G. Larson is George G. Brown Professor of Chemical Engineering and Alfred H. White Distinguished University Professor at the University of Michigan, where he holds joint appointments in macromolecular science and engineering, biomedical engineering, and mechanical engineering. He is internationally recognized for his research contributions to the fields of polymer physics and complex fluid rheology, especially in the development of theory and computational simulations. Notably, Larson and collaborators discovered new types of viscoelastic instabilities for polymer molecules and developed predictive theories for their flow behavior. He has written numerous scientific papers and two books on these subjects, including a 1998 textbook, “The Structure and Rheology of Complex Fluids”.
Shelly R. Peyton is an American chemist who is the Armstrong Professional Development Professor at the University of Massachusetts Amherst. Her research considers the development of biomaterials to investigate metastatic cancer and potential new therapies.
Morton Mace Denn is an Albert Einstein Professor of Science and Engineering Emeritus at the City College of New York (CCNY). He is a member of the National Academy of Engineering and a Fellow of the American Academy of Arts and Sciences.
Lynn Walker is a Professor of Chemical Engineering at Carnegie Mellon University. Her research considers the rheology of complex fluids and how nanostructure impacts the behavior of complex systems. She is a Fellow of the American Institute of Chemical Engineers, the Society of Rheology, and the American Physical Society.
Sally L. McArthur is an Australian materials scientist who is Professor of Biomedical Engineering at Swinburne University of Technology and Research Scientist at CSIRO. Her research considers the development of novel biomaterials for biomedical, nutritional and environmental applications. She was elected Fellow of the Australian Academy of Technology and Engineering in 2021.
Tatiana Segura is an American biomedical engineer who is a professor at Duke University. Her research considers biomedical engineering solutions to promote cell growth. She was elected Fellow of the American Institute for Medical and Biological Engineering in 2017 and awarded the Acta Biomaterialia Silver Medal in 2021.
Kristyn Simcha Masters is an American bioengineer who is professor and Chair of the Department of Bioengineering at the University of Colorado Denver. She works as Director of the Anschutz Medical Campus Center. Her research looks to create tissue-engineered models of disease, with a focus on cancer and cardiac disease.
