聚氰基丙烯酸正丁酯荧光纳米微球的制备及其在小鼠体内分布情况研究

The preparation and tissue distributions of indocyanine green polybutylcyanoacrylate nanoparticle

目的制备不同粒径聚氰基丙烯酸正丁酯复合荧光纳米微球(ICG-PBCA-NPs),并研究其在小鼠各组织中的分布情况。方法通过调控乳化聚合过程中的温度、搅拌速度、稳定剂及原料的量制备不同粒径的ICG-PBCA-NPs。用紫外/可见光分光光度计测定ICG溶液805 nm吸光度A值,绘制ICG溶液浓度的标准曲线,计算ICG浓度与A值的相关公式。将小鼠随机分为6组,每组于给药后0.5、1、5、12 h处死小鼠,分别提取各组小鼠肝、肾、脾、心、胰腺样品制备成匀浆,以荧光分光光度计测定ICG的A值后利用标准曲线计算ICG浓度。将各时间点获得的肝、肾、脾、心、胰腺样品制作冰冻切片观察荧光。结果成功制得(25.0±7.6)nm、(49.0±8.6)nm、(88.0±20.5)nm、(145.0±13.5)nm、(205.0±8.4)nm 5种粒径ICG-PBCA-NPs。(25.0±7.6)nm组ICG-PBCA-NPs于小鼠各组织中均未见明显分布。胰腺组织中(49.0±8.6)nm组荧光强度明显强于其他各组,肝脏、脾脏中(145.0±13.5)nm组荧光强度最强。心脏荧光强度随粒径变化不大。随着粒径减小,ICG-PBCA-NPs在各组织中最强荧光出现时间缩短。结论(49.0±8.6)nm ICG-PBCA-NPs对胰腺靶向性最强。不同纳米粒径对ICG-PBCA-NPs在体内的分布影响显著,考虑粒径对ICG-PBCA-NPs体内分布的影响有可能更好地指导其在未来医学中的应用。

Objective To prepare various ranges of diameter of indocyanine green polybutylcyanoacrylate nanoparti- cle （ICG-PBCA-NPs） and to observe the different tissue distributions of ICG-PBCA-NPs in the mice body. Methods Different diameters of ICG-PBCA-NPs were prepared by regulating the temperature, the stirring speed, the amount of the stabilizer and the raw material during the emulsion polymerization. The absorbency （A value） of ICG solution was meas- ured at 805 nm with ultraviolet/visible specrtromete. The standard curve of concentration of ICG was drawn and the relat- ed equation of concentration of ICG and the A value was calculated. Mice were randomly divided into 6 groups. ICG con- centrations were determined by the standard curve, when obtaining the samples from liver, kidney, spleen, heart and pancreas at 0.5,1,5 and 12 hours after the injection respectively. At the same time, organs removed from mice were sac- rificed for frozen section fluorescence examinations. Results （25.0 ± 7.6） nm, （49.0 ± 8.6） nm, （ 88.0 ± 20.5 ） nm, （ 145.0 ± 13.5） nm, （205.0 ± 8.4） nm diameters of five kinds of ICG-PBCA-NPs were prepared successfully. In （25.0 ± 7.6） nm group, [CG-PBCA-NPs showed no obvious distribution in various tissues of mice. In （49.0 ± 8.6） nm group, pancreatic tissues＇ fluorescence intensity was significantly stronger than the other groups. While liver, spleen showed fluorescence intensity of the strongest was （145.0 ± 13.5） nm. Fluorescence intensity changed little in heart. With the increase of diameter of nanoparticle, the strongest fluorescence of various tissues shortened. Conclusion ICG- PBCA-NPs with （49 ± 8.6） nm diameter has the best pancreas targeting. The various ranges of diameter could affect the biodistribution of ICG-PBCA-NPs dramatically, which may provide the guidance for the medical applications of ICG-PB- CA-NPs.