What is the gel principle of sodium alginate?

Calcium alginate can rapidly exchange ions and form gels. With this property, alginate solution can be dripped into aqueous solution containing calcium ions to produce calcium alginate colloid, and the gel fiber can be produced by using a nozzle.

Adding calcium ions into the alginate solution can produce gel jelly. The gel formed by calcium alginate and sodium alginate has thermal irreversibility.

Sodium alginate is a by-product of extracting iodine and mannitol from kelp or Sargassum of brown algae β- D-mannuronic acid（ β- D-mannuronic, m) and α- L-guluronic acid（ α- L-guluronic (g) is connected by pressing (1 → 4) key. The aqueous solution of sodium alginate has high viscosity and has been used as thickener, stabilizer, emulsifier and so on.

Sodium alginate is a non-toxic food, which was included in the United States Pharmacopoeia as early as 1938. Sodium alginate contains a large amount of - COO -, which can show polyanion behavior in aqueous solution and has certain adhesion. It can be used as a drug carrier for the treatment of mucosal tissue.

Under acidic conditions, when - COO - changes to - COOH, the ionization degree decreases, the hydrophilicity of sodium alginate decreases, the molecular chain shrinks, and when the pH value increases, the - COOH group dissociates continuously, the hydrophilicity of sodium alginate increases and the molecular chain extends.

Therefore, sodium alginate has obvious pH sensitivity. Alginate can form gel rapidly under extremely mild conditions. When Ca2+ and Sr2+ exist, the Na+ on G unit is exchanged with two valence cations, and G units accumulate to form a cross-linked network structure, thus forming hydrogel.

The conditions for forming alginate gel are mild, which can avoid the inactivation of sensitive substances such as sensitive drugs, proteins, cells and enzymes. Because of these excellent characteristics, sodium alginate has been widely used in food industry and medicine.

Taishen biology is a sodium alginate manufacturer, which produces Shandong sodium alginate, potassium alginate and carrageenan. Welcome new and old customers to inquire.