Relying on the practice platform of P2 laboratory, researchers reform and explore the contents and forms of experimental teaching for pathogenic biology and immunology, creating an innovative experimental teaching system suitable for training medical students' professional quality and innovative ability. By improving teaching conditions (construction of P2 laboratory), improving teaching methods and innovating experimental teaching contents, and introducing comprehensive design experiment, students' consciousnesses of service and biosafety have been strengthened, meanwhile, their ability to analyze and solve problems has been improved, and their critical and creative thinking has been cultivated.

Four impurities were isolated from raw material of clindamycin phosphate (CP), and their structures have been determined. LC-MS was used to determine the molecular weights of the impurities in the raw material of CP. Reversed-phase preparative HPLC was used to prepare them, and their chemical structures were identified by HR-MS and NMR. The four unknown impurities were determined as clindamycin-B-phosphate (1), clindamycin-2,4-diphosphate (2), 3',6'-dehydro clindamycin phosphate (3), epi-clindamycin phosphate (4). Impurity 1 has been included in BP and EP, while 2, 3 and 4 have not. The impurities 2, 3, 4 are first separated from raw material of CP.