PENGARUH KONSENTRASI ALGINAT DAN PENYAMBUNG SILANG CaCl2 TERHADAP PELEPASAN METFORMIN HCl DARI MIKROSFER ALGINAT (Dibuat dengan Metode Gelasi Ionotropik Teknik Aerosolisasi)

The aim of this research was to investigate the effect of alginate concentration and CaCl2 concentration on release profile of metformin HCl from alginate microspheres prepared by ionotropic gelation method with aerosolization technique using Na alginate as polymer and CaCl2 as crosslinker. Metformin HCl- alginate microspheres formed were dried using freeze drying method with maltodextrin as lyoprotectant. The concentrations of alginate used were 1,25% and 1,75%, and CaCl2 concentrations were 3% and 5%. Drug release studies of metformin HCl from microspheres was carried out using thermoshaker for 12 hours which consist of 2 hours in simulated gastric fluid (HCl pH 1,2) then continued in simulated intestinal fluid (PBS pH 7,4) for next 10 hours. On the first 2 hours, the amount of metformin HCl released from microspheres was only 21,63±1,42% to 28,37±1,56% due to shrinkage of alginate at acidic pH. Following in the PBS medium, metformin HCl was released faster than in HCl. The percentage of metformin HCl released from microspheres in 12 hours was within the range 67,15±2,58% to 94,74±3,99%. The release rates of these microspheres were 75,41±1,38%(F1); 94,74±3,99%(F2); 67,15±2,58% (F3); and 88,93±5,28%(F4). By using Factorial Design ANOVA, it was found that release rate of metformin HCl from alginate microspheres is significantly increased with increasing concentration of CaCl2. While increasing alginate concentration significantly decrease metformin HCl’s release only on alginate microspheres at 5% CaCl2 concentration. Also there’s no significant difference on on metformin HCl release from microspheres with increasing alginate and CaCl2 concentration simultaneously