Studies On Fluorescent Sensors For Reactive Oxygen Species And Cu²⁺

Reactive Oxygen Species(ROS) contain hydroxyl radical(·OH), superoxide radical(O2·-), singlet(1O2) and hydrogen peroxide(H2O2) and so on, whose continues generation and accumulation could result in many problems, such as aging and oxidative damage. Copper ion(Cu2+) is the third abundant transition metal in body. Moreover, Cu2+ plays an important role in various fundamental physiological processes from bacteria to mammal. Realizing effective and accurate detection of them is of great implications in the field of biology and medicine science.In this paper, coumarin-based sensors for dection H2O2 in lysosome, O2·- and Cu2+ were designed and synthesized, and their fluorescent response and other properties were also studied. Main research contents include:In the first part, The research background is briefly introduced, containing the construction, the response mechanismand and the application in lysosome of fluorescent sensor. Besides, the sensors for hydrogen peroxide, superoxide radical and copper ion based on different mechanisms were described.In the second part, a coumarin-based two-photon fluorescent sensor Lyso-HP specifically targeting lysosome to monitor H2O2 was developed. Lyso-HP showed high selectivity towards H2O2 over other ROS in aqueous solution. Moreover, the good water-solubility and cell permeability of Lyso-HP permitted its application in confocal microscopy imaging of living Hela cells. Probe Lyso-HP was capable of imaging endogenous and exogenous H2O2. Furtherly, the colocalization experiment confirmed the probe could successfully target the lysosome.In the third part, a coumarin-based fluorescent sensor Lyso-S can selectively recognize O2·-was designed and synthesized, and its fluorescence properties indicated that Lyso-S displayed highly seletive response to O2·- with a quite low detection limit. Lyso-S responsed linearly toward O2·- under physiological conditions and exhibited favourable recognition for O2·- by deprotection reaction.In the forth part, a coumarin-based fluorescent sensor 3 possessing a good response for Cu2+ was synthesized. Sensor 3 displayed outstanding sensitive and selective response to Cu2+ with a low detection limit, which can be used to measure the concention of Cu2+ in blood.