An object of the present invention is to provide a method for efficiently removing a residual organic solvent in a biopolymer structure. The present invention provides a method for removing an organic solvent contained in a biopolymer structure from the structure, (1) wherein the structure is placed in an atmosphere containing a solvent other than the organic solvent so as to remove the organic solvent, or (2) wherein the organic solvent is removed by washing the structure with a solution mainly containing water, or (3) wherein the structure contains a hydrophilic compound.

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