Miscibility studies of indomethacin and Eudragit® E PO by thermal, rheological, and spectroscopic analysis

Document Type

Article

Publication Date

1-1-2012

Abstract

The objective of this study is to understand the underlying mechanisms responsible for the superior stability of indomethacin (INM)-Eudragit® E PO (E PO) system by exploring the miscibility and intermolecular interactions through the combination of thermal, rheological, and spectroscopic analysis. The zero shear-rate viscosity drops monotonically with the increase of INM concentration at 145°C, suggesting that E PO and INM form a solution and the small molecular drug acts as a plasticizer. Flow activation energy was calculated from the viscosity data at different temperature. The glass transition temperature (Tg) of the mixture at different composition was determined using differential scanning calorimetry. The Tg and flow activation energy peak at the INM concentration around 60%-70%. Fourier transform infrared analysis provided direct evidence for the intermolecular ionic interactions, which may disrupt the dimer formation of amorphous INM. The study explained the superior stability of INM-E PO mixtures, and demonstrated that a combination of thermal, rheological, and spectroscopic technologies can help us to obtain a full picture of the drug-polymer interactions and to determine the formulation and processing conditions. © 2012 Wiley Periodicals, Inc. and the American Pharmacists Association.

Identifier

84862800151 (Scopus)

Publication Title

Journal of Pharmaceutical Sciences

External Full Text Location

https://doi.org/10.1002/jps.23075

e-ISSN

15206017

ISSN

00223549

First Page

2204

Last Page

2212

Issue

6

Volume

101

Grant

DAAE30 03 D1015

Fund Ref

National Science Foundation

This document is currently not available here.

Share

COinS