Design And Properties Of Fluorescent Probes Based On The Detection Of Reactive Oxygen Species(ROS)

Fluorescent imaging techniques,based on the development of fluorescent probes which are of unparalleled advantages(such as easy operation,high sensitivity,good selectivity,high spatial and temporal resolution,short response time,non-damaging sample preparation,and rapid real-time in-situ detection),have been widely used inbiomedicalpresent,a large number of fluorescent probes are widely used in the real-time monitoring of biologically active molecules and the diagnosis of diseases,even in the navigation of surgery,which play an important role in the fields of biomedicine and medical diagnosis.With the goal of biomedicine applications and detection of some disease related with active oxygen molecules.In this paper,several fluorescent probes have been designed and synthesized for the detection of peroxynitrite and hypochlorous acid.ourresearch work is as follows:1. Four fluorescent probes with double spiral ring structure were designed and synthesized by covalent cross-linking fluorescein or rhodamine with spiropyran.The optical performance of the fluorescent probes were tested and the results showed that FLSP has the highly selectivity to ONOO~-.In the obsence of ONOO~-,the double spiral ring structure of the probe is in a closed-loop state,and the fluorescence shows a"Turn Off"state.After adding ONOO~-,due to the strong oxidation characteristics of ONOO~-,the hydroxyl group on the fluorescein is oxidized and electron rearrangement occurs,causing both fluorescein and spiropyran to open the ring,the fluorescence shows a"Turn On"state,realizing the detection of ONOO~-based on the enhancement of fluorescent signal.The linear range of the probe response to ONOO~-is 20-100?M,and the detection limit is 122 n M.2. So far,most of the ONOO~-fluorescent probes are single channel changes,based on the structure of rhodamine,we designed a ratio fluorescent probe Rhod-DCM-B which can achieve ratio detection of ONOO~-.The dicyanomethylene-4hydropyran was introduced in the3 rd position of the probe,because the dicyanomethylene-4hydropyran is conjugated to rhodamine,its fluorescence emission red shift to 670 nm which is in the near infrared region,and we use the phenylboronic acid ester as a recognition group for ONOO~-.After adding ONOO~-,the phenylboronate ester was removed,and the ring of rhodamine was opened,showing the fluorescence emission of rhodamine,with the increase of ONOO~-,the fluorescence emission peak at 670 nm is gradually weakening,and the fluorescence emission peak at 570 nm is gradually increasing,thereby realizing the ratio detection of ONOO~-.The linear range of the probe response to ONOO~-is 1-20?M,and the detection limit is 52 n M.3. A fluorescent probe PD was designed and synthesized based on the dihydropyridine side group,which can detect HCl O with high selectivity,and we proposed a new recognition mechanism.The probe itself shows a fluorescence emission peak at 445 nm,after adding of HCl O,the addition of HCl O with the unsaturated bond of the pendant dihydropyridine group destroys the degree of conjugation and quenches the fluorescence at 445 nm.Due to its special reaction mechanism,the probe has high selectivity to HCl O,and the mechanism has been verified by mass spectrometry analysis.The results show that the linear response of the probe to HCl O is 1-8?M,and the detection limit is 51 n M.The probe has been successfully used for the detection of exogenous and endogenous HCl O.