Encapsulation and drug release of poorly water soluble nifedipine from bio-carriers

Abstract

Controlled drug delivery is one of the most intruding field in pharmaceutical research. It is desired for most of the drugs due to safety and efficacy reasons. Another emerging field is improving the bioavailability of poorly water-soluble drugs. By encapsulating such drugs into biodegradable polysaccharide materials both, improved bioavailability and controlled drug release is readily expected. Nifedipine, used as a model drug, was encapsulated within polysaccharide gels by the novel ethanol induced gelation method. Wet materials were processed by supercritical technology to retain its form and structure. Swelling and in-vitro dissolution tests were performed to investigate the swelling of aerogels and release behavior of nifedipine within body fluids. It was observed that guar and xanthan are not the best candidates for oral delivery of nifedipine, since the release was prolonged to 14days. Oppositely, pectin and alginate are both suitable for nifedipine encapsulation as they released 100% of nifedipine within the first 5h. Higher drug loading was achieved by pectin aerogels most likely due to their higher surface area.