The present invention relates to a solid composition comprising a first component selected from the group consisting of chitosan, chitin, derivatives of chitosan, derivatives of chitin, and any combination thereof； at least one triprotic acid； and at least one solubilising acid. Preferably the triprotic acid is citric acid and the solubilising acid is a monoprotic acid such as lactic acid. Also claimed is a wound dressing comprising the composition and the use of the composition as a therapeutic agent and in the treatment of wounds. The composition may be used to disrupt and kill bacteria within a biofilm and also prevent biofilm formation. The method of manufacturing the composition comprises the steps of coating at least a portion of the first component with the at least one triprotic acid and the at least one solubilising acid and/or absorbing into at least a portion of the first component the at least one triprotic acid and the at least one solubilising acid.
