一种超声控制的聚多肽纳米释药系统的制备和表征

Preparation and characterization of an ultrasound-controlled polypeptide nanoparticle drug release system

目的:设计和制备一种可实现超声控制的聚多肽纳米释药系统,并表征其药物包载率和超声后的释放率。方法:通过分别加入5K、10K和20K的聚乙二醇胺引发剂和聚合度20、聚合度30和聚合度40的聚多肽以合成8种不同的聚多肽纳米释药系统,包括5K引发剂聚合度20[5K(1:20)]、5K(1:30)、5K(1:40)、10K(1:20)、10K(1:30)、10K(1:40)、20K(1:30)和20K(1:40)的聚多肽纳米释药系统。利用聚多肽侧链可修饰的特点,引入声敏剂,并通过紫外可见光表征声敏剂在聚多肽上的修饰,结合萤火虫荧光素酶对ATP的专一性反应,表征包载ATP的超声控制的聚多肽纳米释药系统的包载率、包载后粒径、超声粒径变化和超声响应的释放率。分析不同超声功率、超声时间对ATP释放率的影响。结果:8种超声控制的聚多肽纳米释药系统中,5K(1:40)的超声控制的聚多肽纳米释药系统无法溶解,其他7种超声控制的聚多肽纳米释药系统通过紫外可见光证实了声敏剂的修饰,溶解性较好;均可以实现对ATP的包载,并且均具有超声响应性,在超声后显示出不同程度的粒径减小和ATP释放;超声后10K(1:30)的聚多肽纳米释药系统ATP释放率最高,可达到15%,与5K(1:20)、5K(1:30)、10K(1:20)、10K(1:40)、20K(1:30)和20K(1:40)的聚多肽纳米释药系统比差异有统计学意义(P<0.05)。10K(1:30)的聚多肽纳米释药系统具有良好的载药稳定性,未经超声处理条件下,在24 h内ATP含量和粒径与0 h比差异无统计学意义(P>0.05)。10K(1:30)的聚多肽纳米释药系统的药物释放率受超声功率和超声时间影响,在相同超声时间下,随着超声功率的增加,ATP释放率也逐渐增加,其中1.0 Wcm^(-2)组与0.5 Wcm^(-2)组、1.5 Wcm^(-2)组与1.0 Wcm^(-2)组、2.5 Wcm^(-2)组与2.0 Wcm^(-2)组相比差异均有统计学意义(P<0.05)。但随着超声功率的增加,细胞活性也逐渐下降,其中1.5 Wcm^(-2)组与1.0 Wcm^(-2)组、2.0 Wcm^(-2)组与1.5 Wcm^(-2)组、2.5 Wcm^(-2)组与2.0 Wcm^(-2)组比差异均有统计学意义(P<0.05)。在相同超声功率下,随着超声时间的增加,聚多肽纳米释药系统ATP释放率也逐渐增加,其中10 min组与1~8 min组比差异均有统计学意义(P<0.05)。结论:10K(1:30)的超声控制的聚多肽纳米释药系统超声响应性最好,其包载率为23%,粒径129 nm,超声后粒径变化10 nm,超声控制的释放效率能达到15%。超声功率为1.0 Wcm^(-2),超声时间为10 min时具有较好的药物释放效率,同时对细胞损伤也最小,具有更好的安全性。

Objective:To design and prepare an ultrasound-controlled polypeptide nanoparticle drug release system,and to characterize its drug inclusion rate and release rate after ultrasound.Methods:By adding 5K,10K and 20K polyethylene glycol amine initiators and polypeptides with polymerization degree 20,polymerization degree 30 and polymerization degree 40,respectively,eight different types of polypeptide nanoparticle drug release systems were synthesized,including 5K initiator polymerization degree of 20[5K(1:20)],5K(1:30),5K(1:40),10K(1:20),10K(1:30),10K(1:40),20K(1:30)and 20K(1:40).Considering that the side chain of polypeptide can be modified,ultrasound sensitized agent was added,and the modification of ultrasound sensitized agent on polypeptide was characterized by means of UV-visible light.Firefly luciferase has a specific response to ATP,so it can characterize the ATP-coated polypeptide nanoparticle drug release system with ultrasound control,including the inclusion rate,particle size after inclusion,ultrasound particle size change and the release rate of ultrasound response.In addition,the effect of different ultrasound power and ultrasound time on ATP release rate were analyzed.Results:Of 8 kinds of ultrasound-controlled polypeptide nanoparticle drug release systems,the one with 5K(1:40)was insoluble,while the other 7 kinds confirmed the modification of ultrasound sensitized agent through UV-visible light,with good solubility,all of which could realize the inclusion of ATP.In addition,all of them were ultrasound responsive with varying degrees of particle size reduction and ATP release after ultrasound.Among them,the one with 10K initiator polymerization degree of 30 after ultrasound had the highest ATP release rate of 15%,showing statistical difference compared with the ones with 5K(1:20),5K(1:30),10K(1:20),10K(1:40),20K(1:30)and 20K(1:40).The polypeptide nanoparticle drug release system with 10K(1:30)had good drug loading stability.Without ultrasound treatment,there was no significant difference in ATP content and particle size within 24 hours compared with 0 hour.The polypeptide nanoparticle drug release system with 10K(1:30)was influenced by ultrasound power and ultrasound time.Under the same ultrasound time,the ATP release rate gradually increased with the ultrasound power.There was statistical difference between the 1.0 Wcm^(-2) group and the 0.5 Wcm^(-2) group,between the 1.5 Wcm^(-2) group and the 1.0 Wcm^(-2) group,between the 2.5 Wcm^(-2) group and the 2.0 Wcm^(-2) group.However,cell viability gradually decreased with the ultrasound power,with statistical difference between the 1.5 Wcm^(-2) group and the 1.0 Wcm^(-2) group,between the 2.0 Wcm^(-2) group and the 1.5 Wcm^(-2) group,between the 2.5 Wcm^(-2) group and the 2.0 Wcm^(-2) group.Under the same ultrasound power,the ATP release rate of the polypeptide nanoparticle drug release system also increased gradually with the ultrasound time,showing statistical difference between the 10 min group and the 1 to 8 min group.Conclusion:The results of a series of screening experiments showed that the ultrasound-controlled polypeptide nanoparticle drug release system with 10K(1:30)has the best ultrasonic response,with 23%inclusion rate and a particle size of 129 nm.The particle size changes by 10 nm after ultrasound,and the ultrasound-controlled release efficiency can reach 15%.When the ultrasound power is 1.0 Wcm^(-2) and the ultrasound time is 10 min,it has good drug release efficiency and better safety with minimal cell damage.