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Titration of DNA/Carbon Nanotube Complexes with Double-Chained Oppositely Charged Surfactants
1/1 dispersions of ss-DNA/CNT complexes in mass ratios were investigated in a mixture with didodecyldimethylammonium bromide, DDAB. Depending on the amounts of the surface-active agent and of the complexes, solutions, precipitates, or re-dissolution occur. DDAB titrates the phosphate groups on the o...
Autores principales: | , |
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Formato: | Online Artículo Texto |
Lenguaje: | English |
Publicado: |
MDPI
2015
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Materias: | |
Acceso en línea: | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5312900/ https://www.ncbi.nlm.nih.gov/pubmed/28347031 http://dx.doi.org/10.3390/nano5020722 |
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author | Tardani, Franco La Mesa, Camillo |
author_facet | Tardani, Franco La Mesa, Camillo |
author_sort | Tardani, Franco |
collection | PubMed |
description | 1/1 dispersions of ss-DNA/CNT complexes in mass ratios were investigated in a mixture with didodecyldimethylammonium bromide, DDAB. Depending on the amounts of the surface-active agent and of the complexes, solutions, precipitates, or re-dissolution occur. DDAB titrates the phosphate groups on the outer surface of the complex and controls the phase sequence in these systems. The combination of different experimental methods determined the phases that occur therein. The results are based on optical absorbance, Dynamic Light Scattering, ionic conductivity, ζ-potential, optical microscopy and AFM. From the above findings a (pseudo)-binary phase diagram is attained. The system has strong similarities with polymer-surfactant mixtures. In fact, its properties conform to cases in which interactions between rigid rod-like polyelectrolytes and oppositely charged species take place. The peculiarities of double-chained DDAB in the process imply significant differences with respect to the behavior of single chain surfactants. In fact, DDAB associates into vesicular entities, when the homologous single chain species forms small micellar aggregates. |
format | Online Article Text |
id | pubmed-5312900 |
institution | National Center for Biotechnology Information |
language | English |
publishDate | 2015 |
publisher | MDPI |
record_format | MEDLINE/PubMed |
spelling | pubmed-53129002017-03-21 Titration of DNA/Carbon Nanotube Complexes with Double-Chained Oppositely Charged Surfactants Tardani, Franco La Mesa, Camillo Nanomaterials (Basel) Article 1/1 dispersions of ss-DNA/CNT complexes in mass ratios were investigated in a mixture with didodecyldimethylammonium bromide, DDAB. Depending on the amounts of the surface-active agent and of the complexes, solutions, precipitates, or re-dissolution occur. DDAB titrates the phosphate groups on the outer surface of the complex and controls the phase sequence in these systems. The combination of different experimental methods determined the phases that occur therein. The results are based on optical absorbance, Dynamic Light Scattering, ionic conductivity, ζ-potential, optical microscopy and AFM. From the above findings a (pseudo)-binary phase diagram is attained. The system has strong similarities with polymer-surfactant mixtures. In fact, its properties conform to cases in which interactions between rigid rod-like polyelectrolytes and oppositely charged species take place. The peculiarities of double-chained DDAB in the process imply significant differences with respect to the behavior of single chain surfactants. In fact, DDAB associates into vesicular entities, when the homologous single chain species forms small micellar aggregates. MDPI 2015-04-30 /pmc/articles/PMC5312900/ /pubmed/28347031 http://dx.doi.org/10.3390/nano5020722 Text en © 2015 by the authors; licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution license (http://creativecommons.org/licenses/by/4.0/). |
spellingShingle | Article Tardani, Franco La Mesa, Camillo Titration of DNA/Carbon Nanotube Complexes with Double-Chained Oppositely Charged Surfactants |
title | Titration of DNA/Carbon Nanotube Complexes with Double-Chained Oppositely Charged Surfactants |
title_full | Titration of DNA/Carbon Nanotube Complexes with Double-Chained Oppositely Charged Surfactants |
title_fullStr | Titration of DNA/Carbon Nanotube Complexes with Double-Chained Oppositely Charged Surfactants |
title_full_unstemmed | Titration of DNA/Carbon Nanotube Complexes with Double-Chained Oppositely Charged Surfactants |
title_short | Titration of DNA/Carbon Nanotube Complexes with Double-Chained Oppositely Charged Surfactants |
title_sort | titration of dna/carbon nanotube complexes with double-chained oppositely charged surfactants |
topic | Article |
url | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5312900/ https://www.ncbi.nlm.nih.gov/pubmed/28347031 http://dx.doi.org/10.3390/nano5020722 |
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