Specific excitonic interactions in the aggregates of hyaluronic acid and cyanine dyes with different lengths of methine group.
Photochem Photobiol Sci
; 15(3): 329-33, 2016 Mar.
Article
em En
| MEDLINE
| ID: mdl-26815728
ABSTRACT
The absorption and circular dichroism (CD) spectra of three types of cyanine dyes with different lengths of methine group (3,3'-diethylthiadicarbocyanine iodide, DTDC; 3,3'-diethylthiacarbocyanine iodide, DTC; and 3,3'-diethylthiacyanine iodide, DTTHC) in an aqueous solution were compared with and without hyaluronic acid (HA), which has a helical structure. DTDC forms chiral H- and J-aggregates, whereas DTC and DTTHC are unable to form any aggregates. DTDC also forms H- and J-aggregates in the presence of sodium polyacrylate (PA) with a random-coil structure; however, the PA-DTDC aggregates exhibit no chirality. These results suggest that the chirality of HA-DTDC aggregates is induced by the helical structure of HA. In 2.4 vol% and 10 vol% methanol, HA-DTDC aggregates displayed different patterns of temperature dependence, whereas no aggregation was observed in 30 vol% methanol. The solubility of DTDC in a mixed solvent of water and methanol is generally improved by the addition of methanol, which prevents the aggregation of DTDC.
Texto completo:
1
Base de dados:
MEDLINE
Assunto principal:
Carbocianinas
/
Corantes
/
Ácido Hialurônico
Idioma:
En
Ano de publicação:
2016
Tipo de documento:
Article