Abstract:
:The kinetics of J-aggregate formation has been studied for two chromophores, tetrakis-4-sulfonatophenylporphine in an acid medium and pseudoisocyanine on a polyvinylsulfonate template. The assembly processes differ both in their sensitivity to initiation protocols and in the reaction profiles they produce. The porphyrin's assembly kinetics, for example, displays an induction period unlike that of the cyanine dye. Two kinetic models are presented. For the porphyrin, an autocatalytic pathway in which the formation of an aggregation nucleus is rate-determining appears to be applicable; for the pseudoisocyanine dye, an equation derived for diffusion-limited aggregation of a fractal object satisfactorily fits the data. These models are shown to be useful for the analysis of kinetic data obtained for several biologically important aggregation processes.
journal_name
Biophys Jjournal_title
Biophysical journalauthors
Pasternack RF,Fleming C,Herring S,Collings PJ,dePaula J,DeCastro G,Gibbs EJdoi
10.1016/S0006-3495(00)76316-8subject
Has Abstractpub_date
2000-07-01 00:00:00pages
550-60issue
1eissn
0006-3495issn
1542-0086pii
S0006-3495(00)76316-8journal_volume
79pub_type
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