Objective To prepare fibrin-targeted, integration of diagnosis and treatment and multi-functional gelatin nanoparticles, explore their potential of dual-mode imaging and the mechanism and effect of photothermal synergistic drug thrombolytic therapy in vitro, and observe the active-targeting ability of thrombus in vivo. Methods Loaded with alteplase (rt-PA)and Fe3O4 mediated by targeting fibrin polypeptide (Cys-Arg-Glu-Lys-Ala, CREKA), the magnetic gelatin nanoparticles (CREKA-Fe-rt-PA-Gel) were prepared by two-step desolvation and carbodiimide method. The morphology of CREKA-Fe-rt-PA-Gel was observed, and its physical and chemical properties and in vitro safety were detected. Its photoacoustic (PA) and magnetic resonance(MR) imaging features were also verified in vitro. The photothermal performance was monitored, the fibrin and hemoglobin indexes were used to evaluate the thrombolytic effect of photothermal therapy and the ability to damage fibrin network. Carotid artery thrombosis model was constructed with rats and HE staining section was performed to observe the targeting thrombus ability in vivo of the nanoparticles. Results CREKA-Fe-rt-PA-Gel were with uniform particle size, diameter of (254.79±6.83) nm, polydispersity coefficient of 0.09±0.05, surface potential of (5.48±4.60) mV. The CREKA peptide was successfully connected with the target connection rate of 98.66%, the encapsulation efficiency of rt-PA was 23.03%±0.05%, and of Fe3O4 was 92.78%±0.57%, the magnetization curve showed that it has good paramagnetism. The cytotoxicity and hemolysis test in vitro confirmed that CREKA-Fe-rt-PA-Gel had appropriate biological compatibility. At the same time, CREKA-Fe-rt-PA-Gel showed excellent imaging ability of PA and MR imaging in vitro. After laser irradiation, the nano solution heated up rapidly in a concentration-dependent manner,hemoglobin and fibrin in solution increased significantly after incubation with thrombus by near infrared irradiation (P<0.01), and nanoparticles released drugs combined with photothermal therapy could damage the fibrin network. HE staining of carotid artery thrombosis in rats showed good thrombus targeting ability of the nanoparticles in vivo. Conclusion The constructed CREKA-Fe-rt-PA-Gel have potential in dual-mode (PA/MR) imaging, good photothermal properties, outstanding targeting ability for thrombus(fibrin), and excellent thrombolytic ability when combined with photothermal, which is expected to be used in early diagnosis and multi-form treatment in clinical thrombotic diseases.
| 科 Family | 属数 Number of genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) | 属 Genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) |
|---|---|---|---|---|---|---|
| 鹅膏菌科Amanitaceae | 2 | 11 | 5.26 | 鹅膏菌属 Amanita | 10 | 4.78 |
| 小菇科 Mycenaceae | 2 | 12 | 5.74 | 丝盖伞属 Inocybe | 5 | 2.39 |
| 多孔菌科 Polyporaceae | 8 | 14 | 6.70 | 蜡蘑属 Laccaria | 5 | 2.39 |
| 红菇科 Russulaceae | 3 | 23 | 11.00 | 小皮伞属 Marasmius | 6 | 2.87 |
| 小菇属 Mycena | 11 | 5.26 | ||||
| 光柄菇属 Pluteus | 5 | 2.39 | ||||
| 红菇属 Russula | 17 | 8.13 | ||||
| 栓菌属 Trametes | 5 | 2.39 |