LAUSR

Abstract The present review introduces various enzymatic reaction systems employing an external light source (visible or UV light) to initiate enzymatic reaction and/or adjust its reaction rate, that is, photo-manipulation of enzymatic activity. In general, a photon-receptor such as semiconductor with a suitable band gap size is needed to interact with enzymes because enzyme molecules are typically not photosensitive. When irradiated, photocarriers (electrons or holes) in the photon-receptors are transferred from the photo-receptors to enzymes for excitation, and then enzymatic reaction breaks out. Hence, switching of enzymatic activity is achievable by turning on/off the light source. The fact that photocarriers are triggers, indicates that redox enzymes that can be stimulated by negative electrons or positive holes are well-matched for the proposed systems. In addition, it has been reported that light-induced-environmental changes (pH, temperature) around enzymes are also useful for strict control of enzymatic activity.