Gellan formulations

Toxicological studies revealed that gellan is relatively nontoxic to animals when administered as a single large dose (LD = 5000 mg/kg) in the diet (Table 1.3), while an inhalation toxicity test formd it caused no deaths in a group of 10 animals [6]. An eye irritation test described in the above study confirmed the safety of gellan in the case of contact with eyes. Gellan formulations received their first approval for food applications in Japan in 1988. It is now acceptable for food, non-food, cosmetic and pharmaceutical use in the United States, Canada, Australia, Latin America, South America, Asia, and in the European Union [12]. 

S. Miyazaki, H. Aoyama, N. Kawasaki, W. Kubo and D. Attwood, In situ-gelling gellan formulations as vehicles for oral drug delivery, J. Control. Release, 60 287-295,1999. 

Santucci E, Alhaique F, Carafa M, et al. Gellan for the formulation of sustained delivery beads. J Control Release 1996 42 157-164. 

Kubo W, Miyazaki S, Attwood D. Oral sustained delivery of paracetamol from in-situ gelling gellan and sodium alginate formulations. Int Pharm 2003 258(1-2) 55-64. 

Patil S, Sharma S, Nimbalka A, Pawar A. Study of formulation variables on properties of drug-gellan beads by factorial design. Drug Dev Ind Pharm. 2006 32 315-26. 

Gellan gum gum cordia Metformin Gelled beads Gelled bead formulation had adequate % drug entrapment and more than 80% sustained release in 24 h. [152]... 

M. Ahuja, M. Yadav, and S. Kumar, AppHcation of response surface methodology to formulation of ionotropically gelled gum cordia/gellan beads, Carbohydr. Polym., 80 (1),... 

Gellan can be gelled in the tear fluid even at a very low polymer concentration. Due to this property, in physiological conditions where the formulated instilled drops are diluted, gellan can form gel with a high elastic modulus [74]. 

Balasubramaniam et al. successfully formulated indomethacin containing gellan-based in-situ gelling system as a viable alternative to conventional eye drops. These developed formulations provided sustained release of the drug in addition to prolonging the residence time in corneal region, thereby enhancing the ocular bioavailability. The formulated system did not cause any deleterious effects to the ocular tissues [75]. 

Doshi and Tank formulated dummy tablets of gellan using the wet granulation fabrication technique and discovered their feasibility as gastro-retentive tablets [88]. 

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