Bismuth alginate and preparation method and application thereof

The invention relates to preparation of a bismuth-containing compound, in particular to bismuth alginate and a preparation method and application thereof. The structure of the bismuth alginate is shown as Formula 1, wherein n is equal to 200-250. The bismuth alginate is prepared via reaction of algin and bismuth salt or bismuth alkali in alkaline aqueous solution, and the alginic acid is prepared via ethanol precipitation and separation, dehydration, drying and grinding. The bismuth alginate is synthesized with alginic acid as a bismuth carrier, the bismuth content of the bismuth-containing compound is lower than the bismuth content of bismuth preparations universally applied in clinics at present, and the potential toxicity of long-term administration of the bismuth can be reduced. Moreover, the bismuth-containing compound has the biological activity of both bismuth preparations and alginic acid and has multi-functions of protecting the gastric mucosa, neutralizing the gastric acid, reducing the activity of pepsin, killing Hp, and promoting healing of peptic ulcer wounds. Therefore, the bismuth-containing compound has good values in new drug development. Formula I is shown in the description.