{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,7]],"date-time":"2026-01-07T07:23:40Z","timestamp":1767770620999},"reference-count":26,"publisher":"American Chemical Society (ACS)","issue":"26","content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Langmuir"],"published-print":{"date-parts":[[2002,12,1]]},"DOI":"10.1021\/la026336z","type":"journal-article","created":{"date-parts":[[2002,12,17]],"date-time":"2002-12-17T06:59:25Z","timestamp":1040108365000},"page":"10109-10115","source":"Crossref","is-referenced-by-count":23,"title":["Manipulation of the Reactivity of a Synthetic Anthocyanin Analogue in Aqueous Micellar Media"],"prefix":"10.1021","volume":"18","author":[{"given":"Carolina","family":"Vautier-Giongo","sequence":"first","affiliation":[{"name":"Instituto de Qu\u00edmica, Universidade de S\u00e3o Paulo, S\u00e3o Paulo, Brasil, Instituto de Tecnologia Qu\u00edmica e Biol\u00f3gica, ITQB\/UNL, Oeiras, Portugal, and Departamento de Qu\u00edmica, IST\/UTL, Lisbon, Portugal"}]},{"given":"Chang","family":"Yihwa","sequence":"additional","affiliation":[{"name":"Instituto de Qu\u00edmica, Universidade de S\u00e3o Paulo, S\u00e3o Paulo, Brasil, Instituto de Tecnologia Qu\u00edmica e Biol\u00f3gica, ITQB\/UNL, Oeiras, Portugal, and Departamento de Qu\u00edmica, IST\/UTL, Lisbon, Portugal"}]},{"given":"Paulo F.","family":"Moreira,","sequence":"additional","affiliation":[{"name":"Instituto de Qu\u00edmica, Universidade de S\u00e3o Paulo, S\u00e3o Paulo, Brasil, Instituto de Tecnologia Qu\u00edmica e Biol\u00f3gica, ITQB\/UNL, Oeiras, Portugal, and Departamento de Qu\u00edmica, IST\/UTL, Lisbon, Portugal"}]},{"given":"Jo\u00e3o C.","family":"Lima","sequence":"additional","affiliation":[{"name":"Instituto de Qu\u00edmica, Universidade de S\u00e3o Paulo, S\u00e3o Paulo, Brasil, Instituto de Tecnologia Qu\u00edmica e Biol\u00f3gica, ITQB\/UNL, Oeiras, Portugal, and Departamento de Qu\u00edmica, IST\/UTL, Lisbon, Portugal"}]},{"given":"Adilson A.","family":"Freitas","sequence":"additional","affiliation":[{"name":"Instituto de Qu\u00edmica, Universidade de S\u00e3o Paulo, S\u00e3o Paulo, Brasil, Instituto de Tecnologia Qu\u00edmica e Biol\u00f3gica, ITQB\/UNL, Oeiras, Portugal, and Departamento de Qu\u00edmica, IST\/UTL, Lisbon, Portugal"}]},{"given":"Marilene","family":"Alves","sequence":"additional","affiliation":[{"name":"Instituto de Qu\u00edmica, Universidade de S\u00e3o Paulo, S\u00e3o Paulo, Brasil, Instituto de Tecnologia Qu\u00edmica e Biol\u00f3gica, ITQB\/UNL, Oeiras, Portugal, and Departamento de Qu\u00edmica, IST\/UTL, Lisbon, Portugal"}]},{"given":"Frank H.","family":"Quina","sequence":"additional","affiliation":[{"name":"Instituto de Qu\u00edmica, Universidade de S\u00e3o Paulo, S\u00e3o Paulo, Brasil, Instituto de Tecnologia Qu\u00edmica e Biol\u00f3gica, ITQB\/UNL, Oeiras, Portugal, and Departamento de Qu\u00edmica, IST\/UTL, Lisbon, Portugal"}]},{"given":"Antonio L.","family":"Ma\u00e7anita","sequence":"additional","affiliation":[{"name":"Instituto de Qu\u00edmica, Universidade de S\u00e3o Paulo, S\u00e3o Paulo, Brasil, Instituto de Tecnologia Qu\u00edmica e Biol\u00f3gica, ITQB\/UNL, Oeiras, Portugal, and Departamento de Qu\u00edmica, IST\/UTL, Lisbon, Portugal"}]}],"member":"316","published-online":{"date-parts":[[2002,12,17]]},"reference":[{"key":"la026336zb00001\/la026336zb00001_1","doi-asserted-by":"crossref","first-page":"1359","DOI":"10.1021\/ja00447a012","volume":"99","author":"Brouillard R.","year":"1977","journal-title":"J. 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Thus, our laser flash perturbation method only detects A molecules that, at the end of the laser pulse, are incorporated into proton-free SDS micelles. The same is, of course, true for nonionic Triton X-100 and Brij 35 micelles that efficiently incorporate AH+and A but show little or no tendency to concentrate protons. Micellar CTAC is a special case, since incorporation of HMF is only partial (ca. 25%) under our conditions. Here it is instructive to compare the obseved lifetimes of A in the presence of CTAC to those in its absence at the same pH. For A in water, \u03c4aq= 1\/(kp[H+]) = 2.8 \u00d7 10-2\/[H+] (in ns), where we have used the value ofkp= 3.6 \u00d7 1010M-1s-1determined previously.17Thus, for the range of H+concentrations of Table 2, the corresponding lifetimes of the fraction of A that is formed in the aqueous phase would be 90 ns at [H+] = 0.32 mM, 28 ns at [H+] = 1.0 mM, 5 ns at [H+] = 5.6 mM, and <3 ns at all [H+] \u2265 10 mM. Indeed, at pH 2.0 in water no transient signal due to A can be observed due to the rapidity of the reprotonation on the time scale of the laser pulse. Thus, the transient that we detect corresponds exclusively to A that is either formed in the micellar phase or formed near the micellar surface and manages to enter the micelle prior to protonation. Thus, for all micelle types studied here, the rate-limiting step for protonation is the entry of the proton from the intermicellar aqueous phase into a proton-free micelle containing A. Hence, the appropriate proton concentration in eq 1 is indeed [H+]w, and the significance ofkpunambiguous."},{"key":"la026336zb00026\/la026336zb00026_1","doi-asserted-by":"crossref","first-page":"336","DOI":"10.1021\/j100338a066","volume":"93","author":"Ma\u00e7anita A. L.","year":"1989","journal-title":"J. Phys. 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