Interaction of salicylic acid analogues with Pluronic® micelles: Investigations on micellar growth and morphological transition

V. Shah, B. Bharatiya*, V. Patel, M. K. Mishra, A. D. Shukla, D. O. Shah

*Corresponding author for this work

Research output: Contribution to journalArticle (Academic Journal)peer-review

9 Citations (Scopus)


The aqueous solutions of PEO-PPO-PEO type triblock copolymers (Pluronic® P123, P103 and P105) with variations in their total molecular weight and block contribution are investigated for encapsulation of drugs. Two drugs, namely Aspirin (AS) and 5-Methyl Salicylate (MS) having different partition coefficient was studied. The changes in size and micellar dynamics due to formation of drug-polymer complexes are investigated using dynamic light scattering (DLS), dynamic surface tension (DST), Nuclear Magnetic Resonance (NMR) and Small angle neutron scattering (SANS) measurements. Increase in apparent hydrodynamic diameter (D h ) measured by DLS suggests the growth of micelles, which is equally supported by calculated micellar parameters from SANS measurements. The solubilization of drugs within micelles alters the diffusivity of the monomers due to stronger hydrophobic forces leading to highly stable aggregates as concluded by dynamic surface tension measurements. The significant increase in micellar size was noticed in presence of MS, while AS had less prominent effect on micellar growth. The preferential partitioning of drug into the hydrophobic micellar core is the driving force for the possible formation of higher morphologies. The hydrophobic interactions between MS and P123 are confirmed by 1 H NMR. The differences in molecular interactions leading to distinct morphological behavior are explained by the localization of drug within nanocarriers.

Original languageEnglish
Pages (from-to)563-570
Number of pages8
JournalJournal of Molecular Liquids
Early online date29 Dec 2018
Publication statusPublished - 1 Mar 2019


  • Micelles
  • Morphological transition
  • Pluronics®
  • Salicylic acid analogues
  • Small angle neutron scattering


Dive into the research topics of 'Interaction of salicylic acid analogues with Pluronic® micelles: Investigations on micellar growth and morphological transition'. Together they form a unique fingerprint.

Cite this