Synthesis and Binding Affinity of Hydrophobic Tail Containing Naphthalene Derivatives with Different Type of Organized Media

摘要

abstract_textpIn this article, we are introducing the synthesis of two naphthalene derivatives (NPBU (butyl 2-(naphthalene-2-yl)acetate) and NPME (methyl 2-(naphthalene-2-yl)acetate)) having different length of aliphatic tail. These two newly synthesized naphthalene derivative are used as a fluorophore to understand the binding interaction with surfactants (SDS (sodium dodecyl sulfate), CTAB (cetrimonium bromide) and Triton X-100) and also with beta-CD (beta-cyclodextrin). Because of long hydrophobic tail, NPBU is more hydrophobic in nature and showed self-aggregation properties in aqueous medium. Whereas, the short aliphatic tail containing NPME not showed any self-aggregation property in an aqueous medium. Because of hydrophobicity NPBU could binds with the hydrophobic inner core of micelles of SDS, CTSB and Triton X-100. NPBU also formed inclusion complex with inner hydrophobic cavity of beta-CD. However, because of low hydrophobicity NPME, could not able to binds with hydrophobic inner core of micelles and also it was not able to bind with hydrophobic cavity of beta-CD. The calculated CMC (critical micelle concentration) values of SDS, CTAB and Triton X-100 by using NPBU fluorophore are similar to 12 mM, similar to 0.8 mM and similar to 0.12 mM respectively. The NPME binds with beta-CD and formed inclusion complexes NPBU@beta-CD and calculated binding constant was 0.22 x 10(2) M-1. Thus this presented comparative study is showing the importance of a hydrophobic tail, attached to naphthalene molecule. The attachment of a long hydrophobic tail makes the fluorophore sensitive towards microenvironment of surfactants and make naphthalene molecules suitable for investigation of structure and dynamics of micellization of different types of surfactants./p/abstract_text