Utilize este identificador para referenciar este registo:
https://hdl.handle.net/10316/10329
Título: | DNA Phase Behavior in the Presence of Oppositely Charged Surfactants | Autor: | Dias, Rita Mel'nikov, Sergey Lindman, Björn Miguel, Maria G. |
Data: | 28-Nov-2000 | Editora: | American Chemical Society | Citação: | Langmuir. 16:24 (2000) 9577-9583 | Resumo: | The interaction between DNA and alkyltrimethylammonium bromides of various chain lengths has been investigated. It is known that these systems phase separate with the formation of a precipitate; this important feature allows, for example, purification of nucleic acids. Phase maps were drawn for the aqueous systems illustrating the associative phase separation. The boundary of the two-phase region for the dilute part of the phase diagram was evaluated by turbidimetry, in both the absence and presence of salt. The extension of the precipitate region increases strongly with the surfactant alkyl chain length, and we observed no redissolution with an excess of surfactant. The addition of NaBr led to novel interesting findings. The phase diagram studies were correlated with the single molecule conformational behavior of the same systems as studied for very diluted solutions by fluorescence microscopy. DNA exhibits a discrete phase transition in the presence of cationic surfactants from coils to globules. Results demonstrate that the coil−globule coexistence interval is narrow for CTAB and becomes wider for the shorter-chained surfactant. The findings for flexible polyions of lower charge density differ qualitatively from what we find here for DNA. For the first, large amounts of surfactant have to be added before phase separation occurs, and the change in the polyion extension is gradual, indicating an essentially uniform distribution of surfactant aggregates among the different polyions. For DNA, the very low values of surfactant concentration at which phase separation starts demonstrate a different binding interaction; as binding to a polyion starts, further binding is facilitated, and one DNA molecule is saturated before binding starts at another. | URI: | https://hdl.handle.net/10316/10329 | ISSN: | 0743-7463 | DOI: | 10.1021/la000640f | Direitos: | openAccess |
Aparece nas coleções: | FCTUC Química - Artigos em Revistas Internacionais |
Ficheiros deste registo:
Ficheiro | Descrição | Tamanho | Formato | |
---|---|---|---|---|
DNA Phase Behavior in the Presence of Oppositely.pdf | 85.77 kB | Adobe PDF | Ver/Abrir |
Citações SCOPUSTM
197
Visto em 9/nov/2022
Citações WEB OF SCIENCETM
1
188
Visto em 2/mai/2023
Visualizações de página 50
562
Visto em 23/abr/2024
Downloads
364
Visto em 23/abr/2024
Google ScholarTM
Verificar
Altmetric
Altmetric
Todos os registos no repositório estão protegidos por leis de copyright, com todos os direitos reservados.