Details

Autor(en) / Beteiligte

• Simon, Anna J
• Walls-Smith, Luke T
• Freddi, Matthew J
• Fong, Faye Yi
• Gubala, Vladimir
• Plaxco, Kevin W

Titel

Simultaneous Measurement of the Dissolution Kinetics of Responsive DNA Hydrogels at Multiple Length Scales

Ist Teil von

• ACS nano, 2017-01, Vol.11 (1), p.461-468

Ort / Verlag

United States: American Chemical Society

Erscheinungsjahr

2017

Quelle

MEDLINE

Beschreibungen/Notizen

• Recent years have seen increasing study of stimulus-responsive hydrogels constructed from aptamer-connected DNA building blocks. Presumably due to a lack of simple, quantitative tools with which to measure gel responsiveness, however, the literature describing these materials is largely qualitative. In response, we demonstrate here simple, time-resolved, multiscale methods for measuring the response kinetics of these materials. Specifically, by employing trace amounts of fluorophore-quencher labeled cross-linkers and the rheology of entrapped fluorescent particles, we simultaneously measure dissolution at molecular, hundred-nanometer, and hundred-micron length-scales. For our test-bed system, an adenine-responsive hydrogel, we find biphasic response kinetics dependent on both effector concentration and depth within the gel and a dissolution pattern uniform at scales longer than a few times the monomer–monomer distance. Likewise, we find that, in agreement with theoretical predictions, dissolution kinetics over the hundred nanometer length scale exhibit a power-law-like dependence on the fraction of disrupted cross-links before a distinct crossover from solid-like to liquid-like behavior.