基于萤火虫萤光素-萤光素酶系统的生物发光已经被广泛应用在包括生物学、医学、药学等研究领域，但萤光素体内代谢过快导致的发光持续时间短的缺点阻碍了其在生物活体分析方面的进一步应用。针对这一瓶颈，本项目在前期研究基础上，通过对萤光素的分子模拟，应用同位素动力学效应，在底物的代谢活性位点引入氘原子。一方面降低萤光素的代谢速度，延长体内半衰期，增加体内的底物水平和保留时间，提高发光时间和发光强度；另外一方面，由于氘原子与氢原子的大小与性质接近，对底物-酶的相互作用影响小，能有效保留原有的生物发光活性。在此基础上，本项目将进一步研究和评价氘代萤光素的理化光学性质、药代动力学和药效学特征、生物安全性及其生物成像应用。本项目的实施将有助于突破现有生物发光瓶颈，为实现长时间活体可视化分析提供有价值的思路。

Bioluminescence based on firefly luciferase-luciferase system has been widely applied in many fields including biology, medicine, pharmacy. However the fast metabolism of luciferin leads to a short duration of bioluminescence signal which greatly hinders its further applications in vivo analysis. To solve this problem, the deuterium atoms are introduced into the metabolic active sites of the luciferin on the basis of the molecular modeling and deuterium isotope strategy. On the one hand, the C-D bond can reduce the metabolic reaction rate of luciferin, increase its level and retention time in vivo, resulting in higher signal intensity and longer luminescence duration. On the other hand, due to the similar size and nature of the deuterium atom and hydrogen atom, this modification would not effect luciferin-luciferase interaction and the original bioluminescent activity could be retained. On this basis, the project will further evaluate the physicochemical and optical properties, pharmacokinetics and pharmacodynamics characteristics of deuterated luciferin, and study its biosafety and bioimaging applications. This project will help to break through the existing bottlenecks in bioluminescence filed and provide valuable ideas to achieve long-term in vivo visualization analysis.