Gellan gum is a bacteria-produced water-soluble anionic polysaccharide which is being investigated by scientists at the University of Huddersfield, UK, as an option for drug companies in developing orally and nasally delivered delayed release drugs.
"The formulation consists of microscopic gel particles which collectively are pourable and can be administered with a spoon," lead scientist Alan Smith and Senior Lecturer in Pharmaceutics atHuddersfield told in-Pharmatechnologist.com.
"The gel is acid insoluble and locks the drug within the gel when it’s in the stomach. When the medicine moves from the stomach to the intestine the gel dissolves - due to the increase in pH - releasing the drug."
There are very few commercially available modified release oral liquids, Smith added, and so this technology could be beneficial for drugmakers looking to target specific populations such as paediatrics and geriatrics who find conventional solid dosage forms difficult to swallow.
"These patient groups usually prefer oral liquids, however, this creates problems when modified release formulations are required to prevent irritation of the stomach or to slowly release the drug for a longer effect."
While Smith and his team will continue to optimise formulations and will assess the long term stability, he told us pharma firms are already looking towards the research for their modified release needs, "due to the simple manufacturing procedure and potential to tune the formulations for different applications."
Nasally viable
As well as administration by mouth, the team is looking into using the tech in nasal delivery.
A recent entry into the International Journal of Pharmaceutics entitled Development of mucoadhesive sprayable gellan gum fluid gels (doi:10.1016/j.ijpharm.2015.04.01) found that gellan gum could be used to develop a more effective nasal spray, addressing the natural way the nasal cavity protects itself by adding mucoadhesive polymers which aids retention of the API
"The results demonstrated that by preparing fluid gels of high acyl gellan, the rheological properties were sufficient to spray through a standard nasal spray device," the study concluded. "Moreover fluid gels also significantly enhance both high acyl and low acyl gellan mucoadhesion properties."