Investigation of factors influencing drug release using calcium alginate polymer

The effects of mixing, the sodium alginate concentration, and calcium chlor ide concentration on the release of sulphamethoxazole (model drug) impregna ted in calcium alginate beads were investigated and evaluated. The release behaviour of the sulphamethoxazole from the calcium alginate beads was stud ied in a 0.1N HCl aqueous solution at 37 degrees C. The release rate of the sulphamethoxazole depends heavily on the type of mixers during the formati on of the drug-alginate beads. The highest release rate was achieved when f our-bladed rectangular agitator was used while the lowest release was achie ved when magnetic stirrer was used. The amount of the released sulphamethox azole varies slightly with the variation of the alginate concentration. The total release of sulphamethoxazole when 1% w/v solution of sodium alginate was used found to be 80% of the total drug content while 72% and 68% of th e total drug content for 1.5% and 2% sodium alginate solutions. Three diffe rent calcium chloride concentrations were used (i.e., 5%, 10%, and 15% CaCl 2). The effect of the calcium chloride concentration on the release of the sulphamethoxazole is very pronounced.