A titanium dioxide composite having a molecular recognition capacity is
obtained by modifying the surface of a fine titanium dioxide particle
with a hydrophilic polymer in such a manner that titanium dioxide is
bonded via an ester bond to a carboxyl group of the hydrophilic polymer
and immobilizing a molecule having an ability to specifically bind to a
target molecule to the carboxyl residue of the hydrophilic polymer. Due
to the molecule distinguishability, this titanium dioxide complex can
bind specifically to an endocrine disrupting chemical, a pathogenic
factor, a cancer cell and the like and decompose the same by a
photocatalytic function.