Department of Chemistry and Department of Energy Systems Research, Ajou University, Suwon 16499, South Korea.
ACS Appl Bio Mater. 2021 Apr 19;4(4):2957-2973. doi: 10.1021/acsabm.1c00063. Epub 2021 Mar 11.
Enzyme regulation is crucial in living organisms to catalyze various biosyntheses to maintain several physiological functions. On the contrary, abnormal enzyme activities can affect bioactivities leading to various serious disorders including cancer, Alzheimer's disease, Parkinson's disease, heart disease, and so on. This biological significance led to the development of various techniques to map specific enzyme activities in living systems to understand their role and distribution. Two-photon microscopy (TPM) in particular has emerged as a promising system for real-time bioimaging owing to its robustness, high sensitivity, and noninvasiveness. It was achieved through the use of a two-photon (TP) light source of an optical window (700-1450 nm) beneficial in deeper light penetration and extraordinary spatial selectivity. Therefore, developing enzyme sensors utilized in TPM has significance in obtaining enzyme activities with minimal perturbation. The development of an efficient detection tool for enzymes has been continuously reported in the previous literature; here, we meticulously review the TP design strategies that have been attempted by researchers to develop enzyme TP fluorescent sensors that are proving very useful in providing insights for enzyme investigation in the biological system. In this review, the representative TP enzymatic probes that have been made in the past 5 years and their applications in tissue imaging are discussed in brief. In addition, the prospects and challenges of TP enzymatic probe development are also discussed.
酶的调节在生物体中至关重要，它可以催化各种生物合成反应，以维持多种生理功能。相反，异常的酶活性会影响生物活性，导致各种严重疾病，包括癌症、老年痴呆症、帕金森病、心脏病等。这种生物学意义促使人们开发了各种技术来绘制活系统中特定酶活性的图谱，以了解它们的作用和分布。特别是双光子显微镜（TPM）由于其稳健性、高灵敏度和非侵入性而成为实时生物成像的有前途的系统。它是通过使用光学窗口（700-1450nm）的双光子（TP）光源实现的，该光源有利于更深的光穿透和非凡的空间选择性。因此，开发用于 TPM 的酶传感器对于获得最小干扰的酶活性具有重要意义。在以前的文献中，不断有报道开发用于酶的高效检测工具；在这里，我们详细回顾了研究人员尝试的 TP 设计策略，这些策略已被证明非常有助于在生物系统中研究酶。在这篇综述中，简要讨论了过去 5 年中制作的代表性 TP 酶荧光探针及其在组织成像中的应用。此外，还讨论了 TP 酶探针开发的前景和挑战。
