Sodium Alginate Microspheres of Metformin HCl: Formulation and In Vitro Evaluation

Abstract

Metformin microspheres with sodium alginate alone and in combination with gellan were prepared using an emulsion-cross linking method. The prepared microspheres were evaluated for their physico-chemical characteristics like particle size, morphology using SEM, incorporation efficiency, equilibrium water content (swelling) and in vitro drug release. The effect of various formulation variables like polymer concentration (sodium alginate; and proportion of gellan in microspheres prepared by a combination of sodium alginate and gellan), drug loading, crosslinking agent concentration and cross-linking time on the in vitro dissolution of the prepared microspheres were evaluated. The results showed that both the particle size and the incorporation efficiency were proportional to the polymer concentration. In case of microspheres containing both sodium alginate and gellan, the mean diameter and the incorporation efficiency were higher than the corresponding microspheres containing only alginate, both increasing with an increase in proportion of gellan. The prepared microspheres were found to be discrete and spherical in shape and were successful in sustaining the drug release for 8 hours. Incorporation of gellan caused a significant decrease in drug release. The release followed a biphasic profile, in all cases, characterized by an initial phase of moderate drug release followed by a phase of higher release. Further, the kinetic treatment of the dissolution data revealed the prevalence of matrix diffusion kinetics.

Design and release characteristics of sustained release tablet containing metformin HCl

“…These drawbacks can be overcome by designing a suitable sustained release metformin HCl preparation. Recently several studies have been carried out to investigate the pharmacokinetic and pharmacodynamic advantages of oral controlled release products of metformin HCl (Di Colo et al, 2005;Hu et al, 2006;Balasubramaniam et al, 2007;Basak et al, 2007).…”

Formulation and evaluation of erythropoietin-alginate microspheres at different amount of drug

“…This was because the higher the concentration of the drug, the greater the droplet size produced, resulting in the larger size of the formed microsphere (Balasubramaniam et al, 2007). The microspheres size range generated from the study was 47-50 μm (Balasubramaniam et al, 2007). In addition, increasing the concentrations of medicinal ingredients may also increase the efficiency of encapsulation (Balasubramaniam et al, 2007).…”

“…The higher the concentration of the drug, the higher the microspheres size that is obtained (Wang et al, 2013). In a study conducted by Balasubramaniam et al (2007) on the effect of drug concentration on microsphere size using the emulsification technique, it was found that the greater the concentration of drug used, the greater the microsphere size that is obtained. This was because the higher the concentration of the drug, the greater the droplet size produced, resulting in the larger size of the formed microsphere (Balasubramaniam et al, 2007).…”

Encapsulation and release characteristics of glibenclamide loaded calcium-alginate beads

“…2 In the last decade, there has been considerable interest in natural polymers, such as chitosan, gelatin, polylactic acids, and alginates as drugs carriers because of their adequate biocompatibility and biodegradability. [3][4][5][6] Alginatederived polysaccharides [7][8][9] are of special interest because alginates have gelling properties in the presence of divalent cations such as Ca 2+ , Sr 2+ or Ba 2+ . 10 This phenomenon can be explained by the eggbox model.…”