Abstract: Particles comprising a core based on at least one biodegradable organosoluble polymer. At least a part of the surface of the particles is coated with at least one hyaluronan or a derivative thereof, the hyaluronan being a water-soluble, amphiphilic hyaluronan of which the carboxylic functions are in part transformed to form hydrophobic groups.

Abstract: The invention relates to particles comprising a core based on at least one biodegradable organo-soluble polymer. The inventive particles are characterised in that at least part of the surface thereof is coated with at least one hyaluronan or one of the derivatives thereof, said hyaluronan being a water-soluble, amphiphilic hyaluronan of which the carboxylic functions are in part transformed in order to form hydrophobic groups.

Abstract: The invention relates, as new compounds, to derivatives of tetrameric human haemoglobin corresponding to the covalent coupling of a haemoglobin tetramer and a polycarboxy-substituted compound having at least 4 -COO.sup.- groups, the said polycarboxy-substituted compound effecting an internal crosslinking of the two dimers of haemoglobin and conferring thereon an affinity for oxygen which is compatible with an in vivo use of the conjugate when the natural allosteric effector of haemoglobin is not present. Among carboxy-substituted compounds, special mention is made of benzenehexacarboxylate and benzenetetracarboxylate.

Abstract: The subject of the invention is a procedure for the preparation of water-soluble macromolecular conjugates of hemoglobin, characterized in that:in the first step, Z sites are bound to a polymer P, the Z sites containing, on the one hand, at least one negative charge borne for example by sulfate groups and intended to lead to the formation of an ionic linkage with hemoglobin, and containing, on the other hand, at least one carboxylic group for example intended to lead to the formation of a covalent linkage with hemoglobin,then in the second step, the polymer P containing the Z site(s) is made to react with hemoglobin in the oxygenated form in order to form, on the one hand, at least one ionic linkage between at least one of the Z sites borne by the polymer and hemoglobin and, on the other hand, at least one covalent linkage between the same Z site mentioned above borne by the polymer and hemoglobin.

Abstract: The subject of the invention is a water-soluble macromolecular conjugate of hemoglobin characterized in that it is constitutedon the one hand, by hemoglobin,on the other, by a water-soluble polymer P containing polar groups, this macromolecular conjugate contains Z sites, bound to the polymer P and containing at least one negative charge carried for example by sulfate groups, the polymer P being bound to hemoglobinon the one hand, through the intermediary of at least one linkage established between at least one of the Z sites contained in the polymer and hemoglobin,and, on the other, through the intermediary of at least one covalent linkage established between the polymer and hemoglobin, or between at least one of the Z sites contained in the polymer and hemoglobin.The macromolecular conjugates according to the invention exhibit a lower affinity for oxygen than that of free hemoglobin.