Preparation of nano fibers by dissolving chitosan in a solvent, stretching a stream of the solution into nano fibers and drying the fibers by evaporation
A method of forming nano fibres, comprising the steps of dissolving chitosan in an acidic liquid to form a solution 142, displacing at least some of the acid from the solution while maintaining the pH of the solution low enough to avoid chitosan precipitation, causing movement of at least one individual stream of the at least one formable material and solvent into a working zone 144, stretching the streams into nano fibres with at least two fluid energy fields having different velocities 146, and drying the fibres by evaporation of the solvent during stretching of the streams into nano fibres and collecting the nano fibres after they have been dried 148.