ABSTRACT
Enzymes are widely used in chemical and pharmaceutical industries because of their advantages of high efficiency and specificity. However， the shortcomings of the free enzymes， such as poor stability and difficulty in recycling， limit their application. Therefore， the immobilization and application of enzymes have become one of the research hotspots. The selection of the immobilization carriers is a critical step in the process of enzyme immobilization. Metal-organic frameworks（MOFs）， a kind of porous materials， are formed by the coordination of metal ions or metal clusters with organic ligands. As an emerging immobilization carrier， its advantages such as high porosity， strong stability， and surface modifiability make it ideal for immobilized enzyme carriers. By immobilizing the free enzyme on MOFs， the above mentioned deficiencies of the free enzymes can be effectively solved， which greatly broaden the applicable condition. Ligand fishing is a method to find receptor-specific ligands from complex components， which has the advantages of high efficiency， simple sample pretreatment and high specificity. The MOF-enzyme complex formed by enzyme immobilization can act as a "fishing rod" for ligand fishing， which can screen out the targets from the complex system of components. The complex chemical composition and various active ingredients of traditional Chinese medicine（TCM） make the ligand fishing technology to play a big role in the screening of enzyme inhibitors from TCM. And the screened enzyme inhibitors are expected to be further developed into the lead compounds with good efficacy and low adverse effects， so the immobilized enzymes of MOFs have a wide application in the screening of active ingredients from TCM. Based on this， this paper summarized the methods of immobilized enzymes of MOFs in recent years， analyzed the characteristics， advantages and disadvantages of each method， and summarized the laws of preparation conditions and mechanisms. Meanwhile， the application and future development of immobilized enzymes of MOFs in the field of enzyme inhibitor screening from TCM were also summarized and prospected， with a view to providing a reference for the development of natural ingredients and the modernization of TCM.
ABSTRACT
Objective To analyze the radiation exposure of medical personnel, and to provide real-time radiation dose monitoring data for medical personnel in interventional surgeries. Methods A total of 96 person-times who participated in cardiac surgeries in interventional operating rooms from September 2019 to March 2022 were selected as subjects. The subjects were divided into two groups according to the time progress, with 43 person-times in intervention group and 53 person-times in control group. The subjects in the intervention group were provided with radiation dose monitoring data during surgeries, while the subjects in the control group performed surgeries with routine procedures. The average intraoperative radiation dose rates of the two groups were compared. Results The median radiation dose rate was significantly lower in the intervention group than in the control group (88.80 μSv/h vs 188.40 μSv/h, U = 637.000, P = 0.000). Conclusion Providing real-time radiation dose monitoring data for medical personnel in interventional surgeries can effectively reduce their occupational radiation exposure and improve their occupational radiation protection.