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Title: Less is more when forming gels by dilution
Soft materials that change form or function in response to environmental or user-applied stimuli have a wide range of biomedical applications ( 1 ). Gels can form in water from weakly interacting molecules but can return to the state of a flowing liquid suspension, known as a sol, upon changes in the concentration of the molecules or the applied temperature. This behavior is known as a reentrant phase transition. A gel-to-sol phase transition typically arises from a reduction in concentration, meaning that a gel becomes a sol upon dilution and a sol becomes a gel with increased concentration. On page 213 of this issue, Su et al. ( 2 ) demonstrate a system that exhibits a sol-to-gel transition when diluted, inverting the common behavior of gels. Their observations offer insight into systems that undergo reentrant phase transitions in biology.  more » « less
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Page Range / eLocation ID:
153 to 154
Medium: X
Sponsoring Org:
National Science Foundation
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