Xanthan Gum

Category

Gelling Agents; Stabilizing Agents; Suspending Agents; Sustained-release Agents; Viscosity-increasing Agents

Molecular Formula

(C35H49O29)n

Molecular Weight

100000

Grade

Pharmceutical Excipients

Description

Xanthan gum occurs as a cream- or white-colored, odorless, freeflowing, fine powder.

UNII

TTV12P4NEE

Chemical Name

Xanthan gum

CAS Number

11138-66-2

Synonyms

Corn sugar gum; E415; Grindsted; Keldent; Keltrol; polysaccharide B-1459; Rhodicare S; Rhodigel; Vanzan NF; xanthani gummi; Xantural

Administration route

Oral; rectal and topical

Dosage Form

Oral solutions, suspensions, and tablets; rectal and topical preparations

Stability and Storage Conditions

Xanthan gum is a stable material. Aqueous solutions are stable over a wide pH range (pH 3-12), although they demonstrate maximum stability at pH 4-10 and temperatures of 10-60℃. Xanthan gum solutions of less than 1% w/v concentration may be adversely affected by higher than ambient temperatures: for example, viscosity is reduced. Xanthan gum provides the same thickening, stabilizing, and suspending properties during long-term storage at elevated temperatures as it does at ambient conditions. In addition, it ensures excellent freeze-thaw stability. Solutions are also stable in the presence of enzymes, salts, acids, and bases. Vanzan NF-ST is especially designed for use in systems containing high salt concentrations as it dissolves directly in salt solutions, and its viscosity is relatively unaffected by high salt levels as compared with general purpose grades. The bulk material should be stored in a well-closed container in a cool, dry place.

Source and Preparation

Xanthan gum is a polysaccharide produced by a pure-culture aerobic fermentation of a carbohydrate with Xanthomonas campestris. The polysaccharide is then purified by recovery with propan-2-ol, dried, and milled.

Applications

Xanthan gum is widely used in oral and topical pharmaceutical formulations, cosmetics, and foods as a suspending and stabilizing agent.It is also used as a thickening and emulsifying agent.

Safety

Xanthan gum is widely used in oral and topical pharmaceutical formulations, cosmetics, and food products, and is generally regarded as nontoxic and nonirritant at the levels employed as a pharmaceutical excipient. The estimated acceptable daily intake for xanthan gum has been set by the WHO at up to 10 mg/kg body-weight.No eye or skin irritation has been observed in rabbits and no skin allergy has been observed in guinea pigs following skin exposure.No adverse effects were observed in long term feeding studies with rats (up to 1000 mg/kg/day) and dogs (up to 1000 mg/kg/day). No adverse effects were observed in a three-generation reproduction study with rats (up to 500 mg/kg/day). LD50 (dog, oral): >20 g/kg LD50 (rat, oral): >45 g/kg LD50 (mouse, oral): >1 g/kg LD50 (mouse, IP): >50 mg/kg LD50 (mouse, IV): 100-250 mg/kg

Incompatibilities

Xanthan gum is an anionic material and is not usually compatible with cationic surfactants, polymers, or preservatives, as precipitation occurs. Anionic and amphoteric surfactants at concentrations above 15% w/v cause precipitation of xanthan gum from a solution.