Water-soluble compounds derived from homopolymer or copolymer of maleic anhydride, and applications of the said compounds to supporting biological molecules

A water-soluble compound derived from a homopolymer or copolymer of maleic anhydride, the compound having available anhydride functional groups sufficient to immobilize at least one biological molecule, and hydrolyzed anhydride functional groups, wherein the hydrolyzed anhydride functional groups consist of carboxyl functional groups and functional groups derived from carboxyl functional groups carrying a residue of a compound corresponding to the formula I:

• C.sub.x H.sub.y A.sub.z O.sub.t
• in which:
• A is a nitrogen atom of a primary, secondary or tertiary amine functional group or a sulfur atom of a thiol functional group,
• x, z and t, independently of each other, are non-zero integers, and
• y is a non-zero integer, not less than 5 when A is a nitrogen atom and not less than 4 when A is a sulfur atom.