不同表面电荷纳米颗粒在血管外膜传输通路中的传输行为研究

Study on behavior of different surface charge nanoparticles through the extravascular fluid transport pathway

目的使用MRI观察不同表面电荷Fe3O4纳米颗粒在血管外膜传输通路中的传输行为。材料与方法6~7周龄SD大鼠12只,分为电中性组、正电荷组和负电荷组,每组4只,以下肢太溪穴为注射位点,分别于注射前后用MRI小动物活体成像系统检测3组大鼠的磁共振图像,通过计算、分析注射后其信号降低的体素点数目、位移和速度的变化来显示传输行为。结果经普鲁士蓝染色病理切片验证。结果注射后,电中性组、正电荷组和负电荷组的磁共振图像中均出现明显信号降低的区域;其中信号降低的体积随时间均明显增加(P<0.01);3组信号降低区域增加的速度随时间呈明显下降趋势(P<0.01),3组之间信号降低区域增加的速度明显不同(P<0.05),其中,负电荷组的平均速度明显低于电中性组(P<0.01)和正电荷组(P<0.05);3组信号降低区域的累计位移随时间呈明显上升趋势(P<0.01),药物组间与观测时间的交互作用具有统计学意义(P<0.01),随时间的延长,电中性组(P<0.01)和正电荷组(P<0.05)的累计位移长于负电荷组。普鲁士蓝染色证实Fe3O4纳米颗粒在血管外膜传输通路中传输。结论正电荷和电中性的纳米颗粒在血管外膜传输通路中的传输速度高于负电荷,研究血管外膜传输通路作为给药途径时应考虑表面电荷的影响。

Objective:To observe the transport behavior of different surface charge ferric oxide nanoparticles in the extravascular fluid transport pathway using magnetic resonance imaging.Materials and Methods:Twelve SD rats aged 6-7 weeks were divided into neutral,positive group and negative group,with 4 in each group.The lower extremity Taixi acupoint was the injection site,the magnetic resonance images of the three groups of rats were detected by Bruker's high magnetic field MRI small animal in vivo imaging system before and after injection,and the number of voxel points(volume),displacement and velocity of the signal decreased after injection were calculated and analyzed.Results:After injection,the magnetic resonance images of the electric neutral group,the positive charge group and the negative charge group showed significant decrease in the signal area;the volume of the signal decreased significantly with time(P<0.01).The rate of increase in the signal reduction area of the electric neutral group,the positive charge group and the negative charge group decreased significantly with time(P<0.01),and the cumulative displacement increased.The rate of increase in the signal reduction region between the three groups was significantly different(P<0.05),the average speed of the negative charge group was significantly lower than that of the electric neutral group(P<0.01)and positive charge group(P<0.05).The cumulative displacement of the signal areas of the electric neutral group,the positive charge group and the negative charge group showed a significant upward trend with time(P<0.01),the interaction between the drug groups and the observation time was statistically significant(P<0.01).Over time,the cumulative displacement between drug groups is different,and the cumulative displacement of electrically neutral and positively charged nanoparticles is longer than the negatively charged.Conclusions:The transport speed of positively charged and electrically neutral nanoparticles in the extravascular fluid transport system is higher than the negative charge.The effect of surface charge should be considered when studying the extravascular fluid transport system as the route of administration.