A surface modification method of polysaccharide, the modified
polysaccharide, and a method of culturing and recovery cells using the
same are provided. The surface modification method of polysaccharide
comprises (a) immersing a polysaccharide material in an acid, (b)
immersing the polysaccharide material in an acidic solution containing a
protein, and (c) immersing the polysaccharide material in an alkaline
solution containing bivalent metal ions.