DOI: njcpt.com.ng/101.1.2.19
Corresponding Author: BUILDERS F.Philip
Department of Pharmaceutical Technology and Raw Materials Development,
National Institute of Pharmaceutical Research and Development,
Idu, Abuja, Nigeria.
E-Mail: philsonsky@yahoo.com
Abstract
Background: Hybrid polymers with superior functional properties are developed by physical and chemical means
to improve the physicochemical attributes of individual components.
Objective: To develop an eudragit-starch hybrid polymer with new physicochemical and functional properties as
a potential excipient for drug delivery.
Methods: Composites of eudragit and maize starch were prepared from a homogenous mixture of the two in the
following ratios: 1:1, 1:2.5, 1:5, and 1:10. These were characterized by their flowability, hydration capacity,
swelling capacity in different pH media (pH 4, 7 and 9.2), moisture sorption at different Relative Humidity values
(RH 75, 82 and 100 %) and DSC thermal properties. The analyses were performed in triplicates, and the results
were presented as Mean ± Standard Deviation using Microsoft Excel.
Results: The composites showed an improvement in the flow properties by considering the angle of repose in the
order of eudragit: starch thus, 1:1 > 1:2.5 > 1:5> 1:0 > 1:10 > 0:1. The composites (eudragit: starch) of 1:1 showed
higher values of hydration capacity, moisture uptake, and swelling when compared with the primary components
and the other hybrids. The general moisture and water uptake of both the primary components and hybrids are in
the order 1:1 > 1:2.5 > 1:5 > 1:10 > 1:0 > 0:1. The DSC thermal analysis of the eudragit and starch hybrid (1:1)
showed a glass transition, melting and enthalpy of melting different from those of starch and eudragit.
Conclusion: A new Eudragit-Starch (Eu-St) polymer hybrid was formed, showing physicochemical and
functional properties that are different from those of the primary components in terms of enhanced flowability,
moisture sensitivity and affinity, moisture sorption and swelling capacity that was pH sensitive. Thus,
demonstrating the potential for use as a pharmaceutical excipient.
Keywords: Starch, eudragit, hybrid polymer, functional properties, DSC analysis