We have succeeded in developing a new labeling material for deep in vivo visualization: luminescence substrate “AkaSuke™”. AkaSuke™” has both near-infrared emission characteristics suitable for deep in vivo visualization and water solubility for in vivo administration. In addition, “AkaSuke™” has achieved a 6 times-fold increase in brightness compared to D-luciferin. Focusing on the reaction mechanism between the luminescence substrate (firefly luciferin) and the luminescent enzyme (firefly luciferase) involved in the firefly luminescence, we have realized multicolor luminescence materials covering all visible light and have developed firefly bioluminescence labeling materials by organic synthesis of a number of luciferin derivatives that emit in the near-infrared region, among others. In this study, we have applied these findings to realize high luminescence by using natural enzyme "Fluc".