A novel pH-dependant and double crosslinked polymethacrylate-based polysphere matrix for enteric delivery of isoniazid. (October 2013)

• Record Type: Journal Article
• Authors: Cooppan, Shivaan; Choonara, Yahya E.; du Toit, Lisa C.; Ndesendo, Valence M. K.; Kumar, Pradeep; Pillay, Viness
• Is Part Of: Pharmaceutical development and technology. Volume 18:Number 5(2013)
• Page Start: 1066
• Page End: 1077
• Publication Date: 2013-10
• Subjects: Drug delivery systems -- Periodicals; Pharmaceutical technology -- Periodicals; Drugs -- Administration -- Research -- Periodicals; Drug Delivery Systems -- Periodicals; Pharmaceutical Preparations -- Periodicals; Technology, Pharmaceutical -- Periodicals; 615
• DOI: 10.3109/10837450.2012.685654
• Languages: English
• ISSNs: 1083-7450

Abstract

<abstract> <title> <x xml:space="preserve">Abstract</x> </title> <p>This study aimed at developing double crosslinked isoniazid (INH)-loaded polymethyl-methacrylate-ethylcellulose (PMMA-EC) polyspheres for rate-controlled enteric drug delivery. A PMMA solution was manipulated with the addition of EC to produce polyspheres by drop-wise extrusion into a primary crosslinking solution of AlCl<sub>3</sub> (25% w/v), before adding a second crosslinking solution of either 30% w/v BaCl<sub>2</sub> (polysphere Batch A) or 30% w/v MgCl<sub>2</sub> (polysphere Batch B). The polyspheres were then subjected to FTIR spectroscopic analysis, <italic>in vitro</italic> drug release studies, drug entrapment efficiency (DEE) determination as well as surface area and porositometric investigations. Molecular Mechanics (MM) simulations elucidated the interaction between the cations and the PMMA-EC combination. FTIR spectra revealed an affinity of PMMA for Ba<sup>2+</sup>, Mg<sup>2+</sup> and Al<sup>3+</sup>. SEM showed smooth robust polyspheres ranging between 4–6 mm. Porositometric analysis established that polysphere Batch A had larger pores (315.314 Å<sub>abs</sub>) than Batch B (234.603 Å<sub>abs</sub>). Drug release profiles from polysphere Batch A displayed burst release with 50% INH released within 2 h (<italic>N</italic> = 3) that was attributable to the larger ionic radius of the second crosslinker Ba<sup>2+</sup> compared Mg<sup>2+</sup> which was employed for polysphere Batch B. The latter produced polyspheres with superior control in INH release (<25% within 2 h) (<italic>N</italic> = 3) and a higher DEE with minimal pore formation. The experimental findings were well corroborated by the MM simulations.</p> </abstract>