Novel tamarind seed gum-alginate based multi-particulates for sustained release of dalfampridine using response surface methodology

Abstract

The current study involves development of novel tamarind seed gum - alginate complex microspheres for sustained release of dalfampridine by using Central Composite design in combination with response surface methodology. Polymer ratio (A), agitation speed (B) and concentration of CaCl₂ (C) were selected as independent variables. Dalfampridine loaded microspheres are prepared by ionotropic gelation technique and were evaluated for responses. The software numerical optimization process, surface and contour plots predicted the level of independent variables A, B and C (2.6, 800.412 rpm and 1.1%w/w respectively), for maximum response of drug entrapment efficiency (86.09%), controlled release of drug at 1 h, 6 h, 12 h (29.84%, 67.92%, 86.42%) and optimized particle size (613.212 μm) respectively. Low magnitude of relative error for the optimized formulation confirms the validation of model. Optimized formulation was characterized for compatibility by Fourier Transform infrared spectroscopy and Differential scanning calorimetry. The drug release data was best fitted by first order and Higuchi square root model with non-Fickian diffusion kinetics. Therefore, such an attempt of fabrication of dalfampridine multi-particulates system by using tamarind seed gum and sodium alginate may be useful in a better way, for sustaining the release of drug over 12 h.

Keywords: Multi-particulates; Sodium alginate; Sustained release; Tamarind seed gum.