The present invention relates to methods of producing a homogenous hydrogel comprising hyaluronic acid, or salt thereof, crosslinked with divinylsulfone (DVS), said method comprising the steps of (a) providing an alkaline solution of hyaluronic acid, or salt thereof； (b) adding DVS to the solution of step (a), whereby the hyaluronic acid, or salt thereof, is crosslinked with the DVS to form a gel； (c) treating the gel of step (b) with a buffer, wherein the gel swells and forms a hydrogel comprising hyaluronic acid, or salt thereof, crosslinked with DVS.
