Utjecaj umrežavanja na udio metronidazola u pektinskim zrncima

The purpose of this study was to improve the entrapment efficiency of the water-soluble drug metronidazole using internal cross-linking agents. Calcium pectinate beads containing metronidazole were prepared by dropping a drug-pectin solution in 1% and 5% (m/V) calcium chloride for surface crosslinked beads. For the core cross-linked beads, calcium carbonate was dispersed in the drug-pectin solution. The beads were characterized by particle size, swelling ratio, SEM, DSC, and in vitro drug release. It was found that the beads obtained by core cross linking produced more drug entrapped beads than the surface cross-linked beads. Beads obtained using 1% (m/V) calcium chloride showed more drug entrapment than those obtained using 5% calcium chloride. The core cross-linking of pectin beads reduced drug loss by about 10-20%. The water lodging capacity of beads depended upon gel strength, which is a function of the internal gelling agent and pectin concentration. Complete drug release was observed within 30-60 min in the acidic dissolution medium. This work has showed that the core cross-linking agent increases the water-soluble drug entrapment of in calcium pectinate beads.Svrha istraživanja bila je poboljšati udio vodotopljive ljekovite tvari metronidazola u pripravcima s pektinskim zrncima koristeći sredstva za umrežavnje poput kalcijevog karbonata. Površinski umrežena zrnca kalcijevog pektinata s metronidazolom pripravljena su dokapavanjem otopine lijeka i pektina u 1% i 5% (w/V) otopinu kalcijevog klorida. Zrnca s umreženom jezgrom pripravljena su dispergiranjem kalcijevog karbonata u otopinu ljekovite tvari i pektina. Zrncima su određeni sljedeći parametri: veličina čestica, sposobnost bubrenja, SEM, DSC i oslobađanje ljekovite tvari in vitro. Zrnca dobivena umrežavanjem jezgre sadržavala su veći udio lijeka (1020%) od površinski umreženih zrnaca. Zrnca dobivena s 1% (w/V) otopinom kalcijevog klorida sadržavala su veći udio lijeka od onih dobivenih s 5% otopinom. Kapacitet vezanja vode zrnaca ovisio je o jakosti gela, a jakost gela ovisila je internom agensu za geliranje i koncentraciji pektina. U kiselom mediju ljekovita tvar se u potpunosti oslobodila unutar 3060 minuta