目的 构建一种以肝靶向分子甘草次酸（glycyrrhetinic acid，GA）修饰的细菌纤维素（bacterial cellulose，BC）两亲性纳米载体用于紫杉醇（paclitaxel，PTX）口服给药。方法 以丁二酸酐（succinic anhydride，SA）作为连接臂，将甘草次酸与BC进行偶连，获得GA-BC），采用红外光谱法、核磁共振氢谱法对合成产物进行结构表征。通过超声法制备GA-BC- PTX载药胶束，再通过粒径、ζ电位、透射电子显微镜及临界胶束浓度的测定进行表征，采用稳定性实验、体外释放实验、MTT、细胞摄取、小鼠活体成像实验及斑马鱼安全性实验对该载药系统进行评价。结果 成功构建GA-BC载体，经过红外光谱、核磁共振氢谱等检测证明偶连成功，GA-BC-PTX载药胶束平均粒径为（292.4±3.7）nm，表面电位为（−16.8±0.9）mV，载药量为（17.89±0.61）%，包封率为（59.81±0.73）%，临界胶束质量浓度为0.063 mg/mL，呈均一球形，制备的载体稳定性较好，体外释放实验表明该载体能在胃肠道环境稳定存在，MTT实验表明GA-BC-PTX胶束对HepG2细胞存在明显抑制作用，并通过共聚焦显微镜观察流式细胞仪分析证明HepG2细胞对GA-BC胶束载尼罗红的摄取明显高于游离的尼罗红。通过对小鼠活体成像证明GA-BC聚合物胶束具有肝靶向作用。通过斑马鱼卵安全性检测证明当GA-BC载体质量浓度小于2 mg/mL时，聚合物载体基本不具有生物毒性。结论 GA-BC载体具有良好的生物安全性和肝靶向作用，制备GA-BC- PTX口服载药胶束可以有效抑制肝肿瘤细胞HepG2的生长，为肝癌的靶向治疗提供新的思路。

Objective To establish a bacterial cellulose (BC) amphiphilic nanocarrier modified with the liver- targeted molecule glycyrrhetinic acid (GA) for oral administration of paclitaxel (PTX). Methods Using succinic anhydride as a connecting arm, glycyrrhetinic acid is coupled with bacterial cellulose to obtain a glycyrrhizic acid modified bacterial cellulose carrier (GA-BC). The structure of the combination was detected by IR and ¹H-NMR. The GA-BC-PTX drug-loading micelle was prepared by ultrasonic method, and then characterized by particle size, ζ potential, transmission electron microscopy and critical micelle concentration determination. The drug carrier system was evaluated by stability experiment, in vitro release experiment, MTT, cell uptake, in vivo imaging experiment in mice and zebrafish safety experiment. Results In this experiment, the GA-BC carrier was successfully constructed, and the detection of infrared spectroscopy and nuclear magnetic resonance hydrogen spectroscopy proved that the coupling was successful, the average particle size of the GA-BC-PTX drug-loading micelle was (292.4 ± 3.7) nm, the surface potential was (−16.8 ± 0.9) mV, the drug load was (17.89 ± 0.61)%, the encapsulation rate was (59.81 ± 0.73) %, and the critical micelle concentration was 0.063 mg/mL, which was uniformly spherical, and the prepared carrier stability was good. In vitro release showed that the carrier could be stable in the gastrointestinal environment, MTT experiments showed that GA-BC-PTX micelles had a significant inhibitory effect on HepG2 cells, and the uptake of GA-BC-NR micellar by confocal microscopy was shown to be significantly higher than that of free NR. GA-BC polymer mice are shown to have a hepatic targeting effect by imaging mice in vivo. Zebrafish safety testing proved that when the GA-BC carrier concentration is less than 2 mg/mL, the polymer carrier is basically not biologically toxic. Conclusion GA-BC carrier has good biosafety and liver targeting effect, and prepared GA-BC-PTX oral loading micelles can effectively inhibit the growth of hepatic tumor cells HepG2, providing new ideas for targeted therapy of liver cancer.

黑龙江省自然科学基金重点项目(ZD2022C001);黑龙江头雁创新团队项目和111计划(B20088)