Synthesis Of Lanthanide-Doped Persistent Luminescence Materials And For The Detection And Imaging Of Bioactive Molecule In Living Cells

Persistent luminescence materials is able to save excitation light energy andrelease after the stoppage of the excitation. Persistent luminescence materials can lastfor hours more than ten hours after the stoppage of the excitation. Persistentluminescence materials has found extensive applications in many fields, such asinterior decoration, traffic signs, and artificial righting. Persistent luminescencematerials with long afterglow and high luminescence intensity can separate with otherfluorescent dyes. Persistent luminescence materials is a new type of optical probe forimaging and detection. The signal-to-noise ratio can be significantly improvedbecause of the removal of the background noise originating from in situ excitation.This property makes persistent luminescence materials particularly useful inphotoluminescence （PL） detection and real-time monitoring in bio-analysis. However,the synthesis of persistent luminescence materials needs high sintering temperature,so the nanoparticles are easy to reunion, nanoparticles forming bad. The surfacegroups are less and difficult to modification. Therefore, to decrease the synthesistemperature, improve the luminous intensity, and synthetic good dispersibilitypersistent luminescence nanoparticles have important significance.Nowadays, health has become the most important property of human’s life.Commonly, diets with high contents of fruits are protective against several humandiseases such as cardiovascular diseases and even cancer. Therefore, people areputting more and more attention on antioxidant substances such as vitamin C. VitaminC is also known as ascorbic acid. It is an important substance of the human body andparticipates for the growth and repair of tissues in all parts of the body. Vitamin C is a natural antioxidant and can’t synthesis in the human body that mostly found in fruitsand vegetables. Vitamin C can quench most biologically active radicals. It scavengessuperoxide, nitroxide, hydroxide, hydrogen peroxide and so on. Vitamin C playscrucial roles in electron transport, hydroxylation reactions and oxidative catabolism ofaromatic compounds in animal metabolism. Currently, the detection of intracellularvitamin C is still lack of systematic research, so develop probes for detecting vitaminC has become a hot research.Glutathione （GSH） is an important reducing small molecule mercaptans. It is animportant antioxidant in vivo. Glutathione is the most abundant thiolated tripeptide inmammalian and eukaryotic cells. GSH is an essential endogenous antioxidant thatplays a central role in cellular defense against toxins and free radicals. GSH levels areimplicated in many diseases typically associated with cancer, aging, or heart problems.Thus, it is important to be able to monitor the change of GSH concentration in realtime.In this study, we synthesized a new type material named persistent luminescencematerials. Then, based on this materials, we designed and synthesized a series ofnano-probes for intracellular vitamin C and glutathione detection and imaging. Thisstudy includes five chapters:In chapter1, we outline the reducing species and their significance. It alsodescribes the fluorescent probes for detection vitamin C and glutathione. In addition,we summarize the latest development of the persistent luminescent materialsincluding of types, synthesis methods and imaging applications in vivo.In chapter2, we synthesis of lanthanide-doped persistent luminescence materials.The persistent luminescence materials include different substrates, methods anddopant ions to acquire different emission colour. The persistent luminescencematerials is charactered by XRD, fluorescence spectrum, the afterglow spectrum andafterglow decay curve.In chapter3, intracellular vitamin C detection using CoOOH-modified persistentnanoparticles. The blue persistent nanoparticles were synthesized using the typicalSol-Gel synthesis method. We used ultrasonic precipitation method to modify CoOOH on the surface of the persistent nanoparticles to quench the afterglow. Theluminescence can be turned on by introducing vitamin C that reduces CoOOH intoCo²⁺. The signal-to-noise ratio can be significantly improved because of the removalof the background noise originating from in situ excitation.In chapter4, intracellular glutathione detection using MnO₂-modified persistentnanoparticles. The blue persistent nanoparticles were synthesized using the typicalSol-Gel synthesis method. We used ultrasonic precipitation method to modify MnO₂on the surface of the persistent nanoparticles to quench the afterglow. Theluminescence can be turned on by introducing GSH that reduces MnO₂into Mn²⁺.Thesignal-to-noise ratio can be significantly improved because of the removal of thebackground noise originating from in situ excitation.In chapter5, intracellular vitamin C detection using Fe₃O₄-modified persistentnanoparticles. The persistent nanoparticles were synthesized using the typical Sol-Gelsynthesis method. We used ultrasonic precipitation method to modify Fe₃O₄on thesurface of the persistent nanoparticles to quench the afterglow.The luminescence canbe turned on by introducing vitamin C that reduces Fe₃O₄into Fe²⁺.Thesignal-to-noise ratio can be significantly improved because of the removal of thebackground noise originating from in situ excitation.