{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,1]],"date-time":"2026-04-01T12:04:33Z","timestamp":1775045073140,"version":"3.50.1"},"reference-count":29,"publisher":"MDPI AG","issue":"8","license":[{"start":{"date-parts":[[2014,8,4]],"date-time":"2014-08-04T00:00:00Z","timestamp":1407110400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/3.0\/"}],"funder":[{"DOI":"10.13039\/501100003549","name":"OTKA","doi-asserted-by":"publisher","award":["K84133"],"award-info":[{"award-number":["K84133"]}],"id":[{"id":"10.13039\/501100003549","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100003549","name":"OTKA","doi-asserted-by":"publisher","award":["K109480"],"award-info":[{"award-number":["K109480"]}],"id":[{"id":"10.13039\/501100003549","id-type":"DOI","asserted-by":"publisher"}]},{"name":"FP7","award":["HEALTH-F2-2011-278850"],"award-info":[{"award-number":["HEALTH-F2-2011-278850"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Entropy"],"abstract":"<jats:p>The exclusion zone (EZ) is a boundary region devoid of macromolecules and microscopic particles formed spontaneously in the vicinity of hydrophilic surfaces. The exact mechanisms behind this remarkable phenomenon are still not fully understood and are debated. We measured the short- and long-time-scale kinetics of EZ formation around a Nafion gel embedded in specially designed microfluidic devices. The time-dependent kinetics of EZ formation follow a power law with an exponent of 0.6 that is strikingly close to the value of 0.5 expected for a diffusion-driven process. By using optical tweezers we show that exclusion forces, which are estimated to fall in the sub-pN regime, persist within the fully-developed EZ, suggesting that EZ formation is not a quasi-static but rather an irreversible process. Accordingly, the EZ-forming capacity of the Nafion gel could be exhausted with time, on a scale of hours in the presence of 1 mM Na2HPO4. EZ formation may thus be a non-equilibrium thermodynamic cross-effect coupled to a diffusion-driven transport process. Such phenomena might be particularly important in the living cell by providing mechanical cues within the complex cytoplasmic environment.<\/jats:p>","DOI":"10.3390\/e16084322","type":"journal-article","created":{"date-parts":[[2014,8,4]],"date-time":"2014-08-04T08:06:18Z","timestamp":1407139578000},"page":"4322-4337","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":17,"title":["Exclusion-Zone Dynamics Explored with Microfluidics and Optical Tweezers"],"prefix":"10.3390","volume":"16","author":[{"given":"Istv\u00e1n","family":"Husz\u00e1r","sequence":"first","affiliation":[{"name":"Department of Biophysics and Radiation Biology, Semmelweis University, T\u0171zolt\u00f3 utca 37-47, Budapest H1094, Hungary"}]},{"given":"Zsolt","family":"M\u00e1rtonfalvi","sequence":"additional","affiliation":[{"name":"Department of Biophysics and Radiation Biology, Semmelweis University, T\u0171zolt\u00f3 utca 37-47, Budapest H1094, Hungary"}]},{"given":"Andr\u00e1s","family":"Laki","sequence":"additional","affiliation":[{"name":"Faculty of Information Technology and Bionics, P\u00e1zm\u00e1ny P\u00e9ter University, Pr\u00e1ter utca 50\/A, Budapest H1083, Hungary"}]},{"given":"Krist\u00f3f","family":"Iv\u00e1n","sequence":"additional","affiliation":[{"name":"Faculty of Information Technology and Bionics, P\u00e1zm\u00e1ny P\u00e9ter University, Pr\u00e1ter utca 50\/A, Budapest H1083, Hungary"}]},{"given":"Mikl\u00f3s","family":"Kellermayer","sequence":"additional","affiliation":[{"name":"Department of Biophysics and Radiation Biology, Semmelweis University, T\u0171zolt\u00f3 utca 37-47, Budapest H1094, Hungary"},{"name":"MTA-SE Molecular Biophysics Research Group, Semmelweis University, T\u0171zolt\u00f3 utca 37-47, Budapest H1094, Hungary"}]}],"member":"1968","published-online":{"date-parts":[[2014,8,4]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"031408","DOI":"10.1103\/PhysRevE.68.031408","article-title":"Long-range forces extending from polymer-gel surfaces","volume":"68","author":"Zheng","year":"2003","journal-title":"Phys. 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