Photonic materials with various shapes such as film, array, sphere, and shell have been developed with reactive mesogens doped with chiral dopants. These photonic cholesteric liquid crystal (CLC) materials have been applied to bio-, environmental, and strain sensors. The developed CLC sensors can detect external variations with naked eye through reflected color change. Photonic interpenetrating polymer network (IPN) consisting of networked CLC and polyelectrolyte was adopted to functionalize the CLC structure. The novel photonic biosensors were developed by immobilizing various enzymes at the intertwined polyelectrolyte.