The present invention provides water-soluble reactive esters of carboxy polysaccharides and derivatives thereof. The reactive carboxy polysaccharide derivatives are useful per se in aqueous solutions or specifically for the formation of water-soluble covalent fibrinogen conjugates. A preferred conjugate is a hyaluronic acid-fibrinogen conjugate and fibrin adhesive, clot or matrix derived from it. Methods of preparation and methods of use in tissue repair and regeneration are also disclosed.
