Development and In-Vitro Characterization of Ca-Alginate Beads of Oxytetracycline Hydrochloride for Oral Use: Effect of Process Variables

Abstract

This work investigates the preparation of Oxytetracycline Hydrochloride loaded alginate beads to take advantage of the swelling properties of alginate beads for improving the oral delivery. Variations in polymer concentration, concentration of cross-linking agent and cross-linking time were examined systemically for their effects on the particle size, entrapment efficiency, percent yield, flow properties and In vitro drug release behavior. Calcium alginate (Ca-alginate) beads of Oxytetracycline hydrochloride were prepared by ionic-gelation method. Shape and surface characteristics were determined by scanning electron microscopy (SEM). Average particle size of drug-loaded beads was determined by sieving method. In vitro drug release behavior from Ca-alginate beads were carried out in simulated gastric fluid (SGF) for first 2 h and simulated intestinal fluid (SIF) for the next 6 h. SEM confirmed spherical shape of beads with rough and porous morphology. The average particle size of the beads was in the range of 470.96 ± 15.22 to 709.33 ± 16.28 µm. Results indicated that the average particle size and flow property of the beads increased with an increase in the concentration of polymer and the cross-linking agent as well as the cross-linking time. The entrapment efficiency and percentage yield was found to be in the range of 52.87 ± 1.56 to 61.76 ± 0.96 % and 69.98 ± 0.33 to 78.94 ± 0.43 % respectively. Concentration of the sodium alginate up to 1.75 % w/v, cross-linker concentration up to 2 % w/v and cross-linking time (30 min) shows highest percent entrapment efficiency (61.76 ± 0.96 %) and % yield (78.94 ± 0.43 %). A decrease in the rate and extent of drug release was observed with relative increase in the polymer concentration, cross- linker concentration and cross-linking time. No significant drug-polymer interaction was observed in DSC study. From this study it can be concluded that the natural polymer sodium alginate can prolong the release of Oxytetracycline Hydrochloride.