[The different effects of fe(II)- and fe(III)-ions on the hyaluronic acid of the vitreous body (author's transl)].

Fe(II)-ions reduce the viscosity of a hyaluronic acid solution but do not form a precipitate. Fe(III)-ions only slightly lower the viscosity of hyaluronic acid solutions but cause a brown, water-insoluble iron-hyaluronic acid precipitate. After adding ascorbic acid--concentrate the pH-value as in vitreous body--to the reaction solution, Fe(III)-ions reduce the viscosity too. The iron-hyalurnic acid complex is also destroyed by ascorbate. Therefore, the ascorbate of the vitreous humor plays an important role in the generation of siderosis bulbi.